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A 3D printing replication technique for fabricating digital dentures
Abstract
Digitally fabricated dentures allow clinicians to provide new prostheses for edentulous patients in an efficient manner. One approach uses a replication technique where a prosthesis in need of minor alterations is used as a basis for the definitive prosthesis. Compared with conventional duplication techniques, this method allows for the predictable fabrication of accurate dentures in less time and with increased quality. In this clinical report, interim treatment dentures were scanned and 3D printed to make a replication denture for fabrication of a digital prosthesis with the replication technique.
... Furthermore, duplicate dentures can be used for impression-making and bite registration when fabricating new dentures, making artificial tooth alignment easier than with conventional methods [10,11]. Recently, various digital technologies have been developed to manufacture duplicate dentures [4,[12][13][14][15][16][17][18][19][20][21]. Digital technology is extremely useful in the production of duplicate dentures, not only simplifying the production procedure, but also quickly reproducing dentures in the case of denture loss using the saved three-dimensional (3D) data of the denture shape [22,23]. ...
... However, recent portable optical scanners [15] or an intraoral scanner [16,17] have been used to obtain 3D data of the external shape of dentures in a single scan. Regarding CAM, methods have been reported in which a trial denture form is duplicated from a monolithic wax block [18], or a duplicate denture is directly cut from a resin block [19]. Furthermore, reports on the production of duplicate dentures using the 3DP method have recently increased [4,13,14,16,17,[19][20][21]. ...
... Regarding CAM, methods have been reported in which a trial denture form is duplicated from a monolithic wax block [18], or a duplicate denture is directly cut from a resin block [19]. Furthermore, reports on the production of duplicate dentures using the 3DP method have recently increased [4,13,14,16,17,[19][20][21]. ...
Most reports on duplicate dentures are introduction to fabrication methods or clinical case reports. Only a few studies have verified their clinical effectiveness; hence, evidence to construct useful clinical guidelines for duplicate denture use is lacking. This review aimed to comprehensively investigate reports on duplicate dentures to accumulate evidences that will contribute to the formulation of clinical practice guidelines. Duplicate dentures are effectively used for impression making and bite registration when fabricating new dentures, thereby reducing the number of clinic visits and treatment time. Duplicate denture can also be used as temporary or new dentures. Older people in whom various adaptive abilities have declined, may find it difficult to adjust to new dentures and experience stress, even if the shape is appropriate. Duplicate dentures, which reproduces the shape of old dentures that they are used to, have the advantage of being more familiar to older people and less stressful. When manufacturing duplicate dentures, digital methods such as milling and three-dimensional printing are superior to conventional methods regarding working time and cost. A notable advantage of the digital method is that the denture shape can be saved as digital data, and the denture can be easily duplicated if lost.
... 1,2 This technique is well-suited for treating edentulous patients more precisely and more efficiently than conventional methods, resulting in higher-quality prostheses. 3 Historically, denture duplication involved time-consuming and complex laboratory procedures, which could lead to dimensional changes in the final prosthesis. 4,5 A clinically acceptable CD can be replicated for various purposes preserving CD information such as tooth size and arrangement, occlusal scheme, denture borders extension, and features of denture-bearing area. ...
... Denture replication offers the patient various benefits, including a shorter treatment time, patient comfort, and acceptance as geriatric patients take time to adapt to new dentures. 3 Digitization of CD fabrication is a promising option as it overcomes many drawbacks of conventional technique. 27,28 In this replication technique, the conventional dentures were scanned and the digital denture was fabricated as a replica. ...
... This technique has the advantage of patients' records being saved for future use. 3 The accuracy of 3D-printed dentures was evaluated in vitro in previous studies. 9,29 Wang et al 30 reviewed the accuracy of digital dentures and stated that a 0.3-mm deviation average between the intaglio surface is clinically acceptable. ...
The aim of this report was to digitize traditional denture relining using a digital duplication method, in addition to assessing the wear resistance of three-dimensional (3D) printed denture teeth. A complete denture was relined using light body impression. The denture with impression was scanned yielding a standard tessellation language file that was designed to print the denture base and teeth. The printed teeth were fitted into the sockets of the printed denture base and then bonded using auto-polymerized acrylic resins, followed by finishing and polishing. Dentures were inserted and fit and occlusion were adjusted as needed, and the patient was scheduled for follow-up appointments at one week, three months, and six months. At each follow-up visit, dentures were scanned using a 3Shape E3 desktop scanner and scans were superimposed. The occlusal wear was assessed in reference to the first scan after the denture insertion visit. The accuracy of the intaglio surface of dentures was within clinically acceptable limits. The clinical evaluation of inserted dentures in terms of retention, occlusion, esthetic, and patient satisfaction was encouraging. Using digital duplication, conventional dentures could be relined. The advantages of digital records include eliminating polymerization dimensional changes, and reducing cost and clinical time by minimizing the number of visits, which is particularly helpful with geriatric patients.
... Digital denture duplication has been investigated in previous studies [12][13][14][15][16][17][18]. Clark et al. [12] reported that the digital replication technique of the exciting prosthesis is a proven technique with decreased laboratory steps and required chair time compared with conventional methods. ...
... Renne et al. [14] reported many advantages of digital duplication such as a decreased number of visits, a subsequently decreased cost, decreased labor errors, increased dimensional accuracy due to dimensional changes in duplicating materials, and improved modifications and design of scanned files, in addition to high efficiency and suitable clinical solutions for many cases. Takeda et al. [15] reported that the digital replication technique takes less time and is more accurate compared to conventional duplication. ...
... In another study after creating a standard tessellation language (STL) file, dentures were duplicated using CAD-CAM milling and additive methods [12,13]. Although several studies [12][13][14][15][16][17] have assessed different techniques for digital denture duplication, different scanners, or provided a case report validating specific dental techniques, no studies have compared denture base materials and fabrication technologies in relation to digital denture duplications. ...
Background: Digital technology has been introduced in prosthodontics, and it has been widely used in denture duplication instead of a conventional denture duplication technique. However, research comparing different denture duplication techniques and how they affect the fitting accuracy of the denture base is scarce. Objectives: The aim was to assess the impact of duplication techniques on the accuracy of the fitting surface of computer-aided design and manufacturing (CAD-CAM) milled, 3D-printed, and injection-molded complete denture bases (CDBs). Methodology: This study involved fabricating a mandibular complete denture base with three marked dimples as reference marks (A, B, and C at the incisive papilla, right molar, and left molar areas) using a conventional compression molded technique. This denture was then scanned to generate a standard tessellation language (STL) file; after that, it was duplicated using three different techniques (milling, 3D printing, and injection molding) and five denture base resin materials—two milled CAD-CAM materials (AvaDent and IvoBase), two 3D-printed materials (NextDent and HARZ Labs), and one injection-molded material (iFlextm). Based on the denture base type, the study divided them into five groups (each with n = 10). An evaluation of duplication accuracy was conducted on the fitting surface of each complete denture base (CDB) using two assessment methods. The first method was a two-dimensional evaluation, which entailed linear measurements of the distances (A–B, A–C, and B–C) between reference points on both the scanned reference mandibular denture and the duplicated dentures. Additionally, a three-dimensional superimposition technique was employed, involving the overlay of the STL files of the dentures onto the reference denture’s STL file. The collected data underwent statistical analysis using a one-way analysis of variance and Tukey’s pairwise post hoc tests. Results: Both evaluation techniques showed significant differences in fitting surface accuracy between the tested CDBs (p ˂ 0.001), as indicated by one-way ANOVA. In addition, the milled CDBs (AvaDent and IvoBase) had significantly higher fitting surface accuracy than the other groups (p ˂ 0.001) and were followed by 3D-printed CDBs (NextDent and HARZ Labs), while the injection-molded (iFlextm) CDBs had the lowest accuracy (p ˂ 0.001). Conclusions: The duplication technique of complete dentures using a CAD-CAM milling system produced superior fitting surface accuracy compared to the 3D-printing and injection-molded techniques.
... 5 Growing digital technology has facilitated different denture replication techniques by using an imperfect, existing denture to fabricate a new prosthesis. 6 The replication technique improves denture unsatisfactory features of the intaglio surface, borders, and aesthetics while preserving other ideal features. 6,7 Conventional denture replication entails numerous steps, beginning with the use of a duplicator flask, followed by the pouring of auto-polymerizing resin, and denture finishing and polishing, all of which result in dimensional inaccuracies due to volumetric shrinkage. ...
... 6 The replication technique improves denture unsatisfactory features of the intaglio surface, borders, and aesthetics while preserving other ideal features. 6,7 Conventional denture replication entails numerous steps, beginning with the use of a duplicator flask, followed by the pouring of auto-polymerizing resin, and denture finishing and polishing, all of which result in dimensional inaccuracies due to volumetric shrinkage. 5,8 While digital denture replication begins with denture scanning, followed by denture fabrication using the computer-aided design and computer-aided manufacturing (CAD/CAM) process. ...
... Because they are not subject to polymerization shrinkage, digitally fabricated dentures have high mechanical strength, no surface roughness, and few porosities. 6,13,14 The CAM methods in complete denture construction are either additive manufacturing through 3D printing or subtractive using milling processes. 15 The 3D printed dentures are cheaper but they are used to be temporary dentures due to the low mechanical properties of either 3D printed teeth resin or denture base. ...
Objective:
This technique aims to construct a virtual, well-adapted maxillary denture from an existing, ill-fitting denture in completely edentulous patients.
Clinical considerations:
A functional impression is made using the loose maxillary denture, and a cone beam computed tomography (CBCT) of the entire old denture is carried out. The obtained digital imaging and communication in medicine (DICOM) file was segmented using an image computing platform software (3D slicer). The resultant Standard Tessellation Language (STL) file was 3D printed in porcelain white-like resin, then colored and characterized.
Conclusions:
The technique introduces a high-quality digital denture replicate with good retention, that can replace the traditional duplication technique. It can also be used as a relining method for old dentures. This proposed digital technique reduces the number of clinical appointments while also providing a digital library for future denture manufacture.
Clinical significance:
The proposed technique offers a high-quality digital denture replicate that can replace the traditional duplication technique. This digital technique also reduces the number of clinical appointments required for denture duplication.
... On the other hand, studies on constructing 3D printed dentures are still very limited and constrained to case report studies 18 , although the clinical performances of 3D printed dentures were acceptable 21 . Moreover, the most common use for 3D printing in denture manufacturing was to prepare trial/ temporary dentures and record bases 22 . In addition, it is quite clear throughout the literature that using 3D printed dentures still has a long way to go in terms of considering this treatment as a reliable alternative to conventional complete dentures 22 . ...
... Moreover, the most common use for 3D printing in denture manufacturing was to prepare trial/ temporary dentures and record bases 22 . In addition, it is quite clear throughout the literature that using 3D printed dentures still has a long way to go in terms of considering this treatment as a reliable alternative to conventional complete dentures 22 . ...
... Some researchers started by duplicating an existing denture by using digital technologies as an attempt to reduce the laboratory steps and chair time 14,22 . Kurahashi concluded that the main advantages for duplicating existing dentures by using 3D printing systems were saving on material and treatment time plus reducing the effect of the human factor 23 . ...
The aim of this article was to review the current clinical application of Computer-aided design/computer-aided manufacturing (CAD/CAM) and three dimensional (3D) printed dentures in dental clinics.
Methods: A systematic approach for searching PubMed, Embase, Scopus, and Web of Science databases. The search was performed using a variety of keywords including clinical use AND 3D printed removable dentures OR clinical use AND CAD/CAM removable dentures OR clinical use AND digital removable dentures. Selection criteria included articles written in English and reporting information on clinical applications of digital dentures between 2010 to January 2022.
Results: The findings outlined the main clinical advantages of digital dentures such as saving working time, satisfying clinical results and securing patients records, and also requirement of additional visits to secure esthetic patient satisfaction, good retention and ideal vertical dimension. Many studies recommended performing clinical try-in in regards to provide better results. It was also established that 3D printers are less expensive than milling centers and therefore can be afforded by individual dental professionals.
Conclusion: Digital dentures are a promising treatment and offer superior possibilities in the field of prosthodontics especially in lower-income areas where skilled technicians are scarce. However, there are some limitations in their applications.
... The majority of them (36) 3D printed dental restorative structures and eleven printed test specimens from restorative materials. Most of the restorative structures (28 out of 36) were printed out of polymer-based materials, resulting in removable prosthesisrelated constructs [22][23][24][25][26][27][28][29][30][31][32][33][34], provisional restorations [35][36][37][38][39][40][41][42][43][44][45][46][47], or inlays [48,49]. Nine studies printed ceramic-based restorative structures and they were zirconia-based constructs [50][51][52][53][54][55][56], glass-ceramic crowns [57] or alumina-based crowns [16]. ...
... Nine studies printed ceramic-based restorative structures and they were zirconia-based constructs [50][51][52][53][54][55][56], glass-ceramic crowns [57] or alumina-based crowns [16]. Yet, only 5 studies (gray-shaded in Table 1) included in this review actually applied the 3D printed restorative structures in patients, reporting the clinical cases [29,33,34,36,41]. ...
... It resulted in an optimized process allowing for possible production of high precision molar crowns with dimensional accuracy and high reproducibility. Shim et al., 2020 [60] To [33] To fabricate 3D-printed replication dentures using digital workflow. ...
Objective
To present through a systematic review a qualitative analysis of studies published on stereolithography-based 3D printing of restorative materials and their clinical applicability.
Methods
The literature search was conducted based on the question: “What is the state-of-the-art of available restorative materials for 3D printing based on stereolithography?" Online search was conducted in three databases (MEDLINE/PubMed, Scopus and Web of Science) with no restriction for year of publication. Data are reported based on PRISMA, including publication details such as authors and their countries, year and journal of publication, and study design. The synthesis is focused on describing the dental restorative materials and properties evaluated, applied methods, 3D printers used and clinical applicability.
Results
Studies that fit the inclusion criteria were performed in Asia (21), Europe (16) and USA (10), mostly using polymer-based restorative materials (38) for 3D printing constructs. Stereolithographic-printed ceramic-based restorative structures were evaluated by 9 studies. Many studies reported on dimensional accuracy (14), strength (11) and surface morphology (9) of the printed structures. Antibacterial response, cytotoxicity, internal and marginal fit, fracture and wear resistance, density, viscosity, elastic modulus, hardness, structural shrinkage and reliability, degree of conversion, layer cure depth, fatigue, and color were also evaluated by the included studies. Many of them (11) published a proof of concept as an attempt to demonstrate the clinical feasibility and applicability of the technology to print restorative materials, but only 5 studies actually applied the 3D printed restorative structures in patients, which highlights an increasing interest but limited early-stage translation.
Significance
The fast expansion of stereolithographic-based 3D printing has been impressive and represents a great technological progress with significant disruptive potential. Dentistry has demonstrated an incredible willingness to adapt materials, methods and workflows to this promising digital technology. However, esthetic appearance, wear resistance, wet strength and dimensional accuracy are the main current clinical limitations restricting the progression to functional part production with 3D printing, which may explain the absence of clinical trials and reports on permanent/definitive dental restorative materials and structures.
... 22 In addition, it is quite clear throughout the literature that using 3D printed dentures still has a long way to go in terms of considering this treatment as a reliable alternative to conventional complete dentures. 26 Some researchers started by duplicating an existing denture by using digital technologies as an attempt to reduce the laboratory steps and chair time. 17,26 Kurahashi concluded that the main advantages for duplicating existing dentures by using 3D printing systems were saving on materials and treatment time plus reducing the effect of the human factor. ...
... 26 Some researchers started by duplicating an existing denture by using digital technologies as an attempt to reduce the laboratory steps and chair time. 17,26 Kurahashi concluded that the main advantages for duplicating existing dentures by using 3D printing systems were saving on materials and treatment time plus reducing the effect of the human factor. 27 Cristache suggested using modified PMMA-TiO2 nanocomposite material in 3D printed complete dentures, to study the clinical performance of 3D printed dentures over a period of 18 months. ...
Aim The aim of this article was to review the current clinical application of computer-aided design/computer-aided manufacturing (CAD/CAM) and three-dimensional (3D) printed dentures in dental clinics.
Methods A systematic approach for searching PubMed, Embase, Scopus, and Web of Science databases. The search was performed using a variety of keywords including clinical use AND 3D printed removable dentures OR clinical use AND CAD/CAM removable dentures OR clinical use AND digital removable dentures. Selection criteria included articles written in English and reporting information on clinical applications of digital dentures between 2010 to January 2022.
Results The findings outlined the main clinical advantages of digital dentures such as saving working time, satisfying clinical results and securing patients' records, and also requirement of additional visits to secure aesthetic patient satisfaction, good retention and ideal vertical dimension. Many studies recommended performing clinical try-in with regards to providing better results. It was also established that 3D printers are less expensive than milling centres and therefore can be afforded by individual dental professionals.
Conclusion Digital dentures are a promising option in treating edentulous patients, especially in remote areas where skilful technicians are rare. However, there are some limitations in their applications.
... The often reduced neuroplasticity and stereognostic abilities of elderly edentulous patients may provoke adaptation problems to new complete dentures [13]. In such cases, digitally fabricated duplicate new dentures may be an adequate and efficient solution [14][15][16]. They allow the processing of a high-quality biomaterial and a better adaptation of the intaglio fit, while copying the functional areas of the cameo surface of the existing dentures. ...
... Both are in a more standardized, controlled, easy, fast, and predictable way. 3. The repository of digital data allows any time the fabrication of a spare or replacement denture, the fabrication of a new denture as a copy (duplicate) of the old denture, and an easy rebasing by producing a "new old" denture [14][15][16]. 4. In edentulous patients who are in need of implants, the data may be used for a complete digital workflow by designing and fabricating a diagnostic denture teeth set-up, a provisional denture, a radiographic or surgical template that supports the planning and the placing of implants, and, not least, the fabrication of a final restoration [43]. ...
Purpose of Review
During the last few years, the interest in fabrication of computer-engineered removable complete dentures has grown intensively. Innovative clinical and technological advances are driving forces. They allow (i) the creation of new and more efficient workflows, (ii) an emergence of modified and easier procedures, and (iii) the use of alternative biomaterials with improved properties. The results are a better fit and retention of the digital complete dentures, as well as a generally high satisfaction of patient and clinician, while reducing the number of appointments and the technical input. The purpose of this narrative review is to present the historical, clinical, and technological developments in the field of digital removable complete dentures and to evaluate the future potential of this technology.
Recent Findings
The fabrication of a digital complete denture either by milling separately the base and the denture teeth set-up or by milling a monolithic denture is well investigated. Concurrently the trend for fabricating complete denture bases by using the 3D print technology is growing. There is plenty of research showing that milling dentures from standardized pre-polymerized polymethyl methacrylate pucks guarantee the fabrication of homogenous objects with excellent biomaterial properties. The results indicate a better base adaptation, a higher flexural strength, an improved resistance to denture staining, and no polymerization distortion while milling. Furthermore, a sophisticated milling strategy allows to obtain a detailed and accurate intaglio and cameo surface, which is even exceeded when 3D printing. The clinical and technological freedom, to either combine selectively analog and digital steps or to take a totally digital workflow ending with milling or 3D printing, opens countless opportunities in the field of removable complete dentures. Whatever steps are taken, whatever sophisticated technology is chosen, still only the professional and individual know-how of the dentist in combination with the manual skills and the experience of the dental technologist—including especially the finish of the final product—will lead to a superior teamwork result. Limitations inherent to the milling process are the waste of raw material, the wear of milling tools, and the challenge to access undercut areas; the reasons are the milling bur size, the number of milling axes, and the limited movements of the machining axes. The advantages of additive manufacturing lay in a high resolution of complex geometries and a reduced waste of the biomaterial. As a limitation, the accuracy of the object, i.e. deformation, may be affected by several fabrication parameters, such as the polymerization light intensity, the build direction and angle, the layer thickness and numbers, the amount of supporting structures, and the post-processing procedures. However, with improved materials and techniques, printing may also become a primary method for fabricating digital complete dentures.
Summary
The available clinical and technical information and multiple research demonstrate that the integration of digital steps into the workflow for fabricating removable complete dentures opens countless options, leading to the achievement of an esthetically, functionally, biologically, and technically high-quality end product. However, a longer learning curve must be considered. To simplify the fabrication methods of complete dentures in specific clinical situations, with the aim to increase efficiency and to save resources, is indicated. However, the use of conventional step-by-step approaches may still be valid for complex clinical situations. It is foreseeable that for treating edentulous patients, the evolution of new biomaterials, the introduction of sophisticated digital methods, and the development of improved software will follow attractive workflows with more standardized, easier, achievable, and predictable results. It challenges the clinician to have a more direct impact on denture construction and to provide the patient with the opportunity to participate in the esthetic designing. A generally higher efficiency and satisfaction for all partners involved in the fabrication process of removable complete dentures—patient, dental technologist, and dentist/prosthodontist—is the result. For a dental technologist, it is a great challenge to set up esthetic and functional denture teeth in an edentulous 3D space defined by the maxilla, the mandible, and the oral soft tissues. It is a question of time and partly already existing that machine learning—a branch of artificial intelligence—has the capacity to recognize specific intramaxillary and intermaxillary situations and to deliver an acceptable functional and esthetic denture teeth set-up, at least as a working base. Furthermore, with the introduction of a face scanner, the patient becomes virtually present anytime. Transferring the virtual situation in a physical articulator makes judgments and changes possible in both worlds simultaneously. Innovations such as robot technology still are in their infancy; however, there are aspirations to automatically place denture teeth into a dental arch. There is a great responsibility for a dentist and a dental technologist for fabricating high-quality removable complete dentures. Factors, such as a meticulous diagnosis and treatment planning, a personal communication between the involved persons, and a profound knowledge of the clinical and technical possibilities, should lead to an easy, simple, cost-effective, and highly satisfying denture fabrication workflow. The digitalization in this field already has and will even more activate research and clinical opportunities in the near future. The globally existing many edentulous patients will highly appreciate the excellent results.
... 16 The main aim for them was to reduce the laboratory steps and chair time when fabricating dentures for patients with existing dentures. 16,17 Kurahashi concluded that the main advantages for duplicating existing dentures by using 3D printing systems were saving material and treatment time and reducing the effect of the human factor. 18 Cristache suggested using modified PMMA-TiO 2 nanocomposite material to obtain 3D printed complete dentures. ...
... A further advantage is to manufacture large workpieces such as maxillofacial prostheses with the ability to produce a very precise and complex detail. 1,7,8,17 In contrast, the disadvantages of 3D printed dentures were inferior mechanical strength, compromised esthetics, and complications in some clinical stages such as determining vertical occlusion and try-in and color stability. Moreover, the safe use of these dentures for patients still needs more studies regarding the toxic effects on the human body. ...
The aim of this review is to investigate the use of 3D printing technologies for removable denture fabrication with a focus on the advantages, potentials, disadvantages and barriers.
Methods:
An electronic search of the English language literature from 1970 to March 2020 was carried out in databases such as PubMed/MEDLINE, Embase, Scopus, and Web of Science databases with applying the inclusion and exclusion criteria. The search was performed using a variety of keywords including 3D printing, rapid prototyping, additive manufacturing, dentures/complete dentures.
Results:
A total of 412 publications were retrieved. After applying the inclusion criteria and excluding the studies on CAD/CAM, studies on 3D printed crown and bridge and studies on 3D printed metal framework, 18 articles were identified for reading and analyzing in details. The results have outlined the main 3D printing advantages such as saving working time, satisfying clinical results and securing patients records. The detected disadvantages were the strength, esthetics and material biocompatibility.
Conclusion:
Denture fabrication by 3D printing technology is becoming more common in dental clinics. However, there is still a lack of information about biocompatibility and clinical performance of 3D printed dentures and further studies are essential.
... The main disadvantage of the subtractive manufacturing technique is the waste from unused portions of the PMMA blank. The additive manufacturing, also known as 3D printing, is a method that utilizes photosensitive thermoset liquid monomers to polymerize materials layer by layer, forming the object and its supporting structures [6]. Despite having inferior values for mechanical strength, the additive manufacturing provides several benefits such as reducing material waste, minimizing the number of steps to reach final product, and therefore requiring less human intervention and reducing possibility for errors [7,8]. ...
Background
Digitally fabricated dentures may require relining due to continual alveolar ridge resorption. However, studies evaluating the tensile bond strength (TBS) of digitally fabricated dentures bonded to denture liners are lacking. This study aimed to evaluate the TBS of autopolymerized, heat-polymerized, milled, and 3D printed denture base materials bonded to 2 acrylic-based and 2 silicone-based denture liners, both before and after thermocycling. Additionally, the impact of thermocycling on the TBS were also evaluated.
Methods
The TBS of 4 different denture base materials (Palapress (PL), Vertex Rapid Simplified (VR), Smile CAM total prosthesis (SC), and NextDent denture 3D+ (ND)) bonded to 2 acrylic-based (GC Soft-Liner (GC) and Tokuyama Rebase II (RB)) and 2 silicone-based (Ufi Gel P (UP) and Sofreliner Tough M (ST)) denture liners were tested. Specimens (n = 8) were divided into non-thermocycling and thermocycling groups. Non-thermocycling specimens were tested after 24-hours water immersion, while thermocycling specimens were underwent 5000 cycle and were immediately tested. Mode of failure was examined under a stereomicroscope. Data were analyzed using 2-way ANOVA and Tukey HSD tests (α = 0.05), and independent samples t test (α = 0.05) for TBS between non-thermocycling and thermocycling groups.
Results
For the non-thermocycling groups, within the same denture liner material, no significant differences were found between denture base materials, except the ND + RB group, which had significantly lower TBS. For the thermocycling groups, within the same denture liner material, the TBS in the PL group exhibited the highest and the ND group exhibited the lowest. Within the same denture base material, in both non-thermocycling and thermocycling groups, the TBS in the ST group exhibited the highest; in contrast, that in the GC group exhibited the lowest. No significant differences were observed in TBS between non-thermocycling and thermocycling groups, except for denture base materials bonded to the ST group, SC + UP, and ND + UP groups.
Conclusions
Milled denture base can be relined with acrylic-based or silicone-based denture liner. However, cautions should be exercised when relining 3D printed denture base. Thermocycling did not affect TBS between acrylic-based denture liners and denture bases. In contrast, it affected the bond between silicone-based denture liner and denture base.
... 10,11 This manufacturing technique can produce less waste, ensure cost savings, reduce the need for storage of raw materials, and minimize the environmental impact of the procedure. [12][13][14][15] This approach can also reduce the time of intraoral exposure and the number of appointments to the dental office. [16][17][18][19] Passive seating and marginal fit of prosthetic structures are desirable characteristics of prosthetic restorations. ...
Computer-aided manufacturing (CAM) technology allows the use of different manufacturing techniques. This in vitro study aimed to evaluate the marginal fit of temporary restorations manufactured using conventional chairside methods, milling, and three-dimensional printing. Fifteen 3-element temporary restorations specimens were produced and categorized into three groups: non-digital, obtained using the conventional chairside method (GC); milled (GM); and three-dimensionally printed (GP). Marginal fit was assessed using scanning electron microscopy (SEM) performed under two conditions: one with only the central screw tightened, and the other with all three screws tightened. Horizontal misfit values were categorized as over-, equal-, and under-extended and qualitatively analyzed. Statistical analysis was performed using the Tukey-Kramer test (α=0.05). In the vertical assessment, three-dimensionally printed restorations demonstrated greater misfit than restorations obtained by milling and the conventional chairside method (P<0.05). In the horizontal assessment, the misfit in the GP group was significantly higher than that in the GM and GC groups. Restorations obtained using the conventional chairside method and milled provisional restorations showed more favorable results than three-dimensionally printed restorations.
... Liu, et al. compared traditionally produced and 3D-printed trays based on the deviation in vector magnitudes of implant positions. They stated that 3D-printed trays provided more accurate implant positions [28]. ...
... Additive manufacturing, increasingly recognized as a transformative production technology, plays a pivotal role in various industries due to its efficiency, cost-effectiveness, and capacity for complexity without additional waste [1][2][3][4][5][6][7]. Among the primary methods of additive manufacturing, stereolithography (SLA) is distinguished by its superior surface quality and precision, making it especially suitable for applications in dentistry, where detail and accuracy are most important [8][9][10][11]. ...
In this study, the authors performed a strength analysis of seven groups of commercially available materials based on SLS incremental technology. Test samples were made with Original PRUSA SL1S printers, with 10 samples of each type from 7 resins selected for testing. The tests were carried out on an MTS Bionix machine in a static tensile test, during which the basic mechanical properties were determined. This is also a preliminary study to determine material constants in the Johnson-Cook strength model. The authors then performed numerical simulations to mirror the experimental tests in order to tune the rheological model. In addition, a fracture criterion was determined based on a hybrid FEM/SPH numerical method. This allowed for the expansion of material libraries currently used in numerical simulations, as well as the sensitivity of the materials’ models. In subsequent studies, in order to determine the nature of material destruction, analysis of fracture surfaces was performed using a scanning electron microscope (SEM). The final study was a biocompatibility test to assess the biological properties of the material. The conducted research made it possible to determine the strength properties of resins currently used in 3D printers, expand the libraries of material models in the computational environment (with an error rate of less than 5%), as well as observe the nature of the cracks formed and biocompatibility in the context of predicting the use of these materials for biomedical applications.
... This digital process has significantly accelerated production timelines and offers the advantage of retaining design data in cases involving prosthesis loss or fracture. However, these advancements have had minimal impact on the clinical appointment sequence or the overall workflow [37]. ...
The utilization of computer-assisted design and computer-assisted manufacturing (CAD/CAM) techniques in the creation of complete dentures (CDs) has piqued the interest of many people. This article seeks to provide a comprehensive, critical, and objective analysis of the current knowledge of CDs and related technology. The aim of this study is to assess existing literature concerning 3D-printed complete dentures, covering aspects like innovative biomaterials, manufacturing methods and processes, workflow, and clinical effectiveness. The design of the current study included an initial review of 172 titles, an appraisal of abstracts, and finally a selection of articles for rigorous textual analysis. Inconsistencies discovered throughout the selection process were amicably resolved through discourse, culminating in the identification of 65 items. The publications retrieved from a thorough search of the PubMed, Scopus, and Embase databases spanned the years 1994 to 2023. Contemporary digital technology provides evident advantages, but its successful incorporation necessitates meticulous preparation. In the realm of dental healthcare, the digital workflow showcases versatility and a range of applications.
... Along with the already-mentioned minimization of material waste, another benefit of 3D-printing technology is that it can create multiple objects at one time. It can also be used to create complex designs involving multiple undercuts [18,19,25]. Moreover, 3D printing is an efficient, profitable, and predictable fabrication method [10,26] with the capacity for further development. ...
Data regarding the mechanical properties of three-dimensionally (3D) printed materials for occlusal splint manufacturing are scarce. The aim of the present study was to evaluate the flexural strength and surface hardness of modern 3D-printed occlusal splint materials and compare them with two control groups, namely, milled and conventional cold-polymerized occlusal splint materials. A total of 140 rectangular specimens were manufactured for the present study. The specimens were prepared in accordance with the International Organization for Standardization standards (ISO 20795-1:2013). Five 3D-printed (NextDent Ortho Rigid, Dental LT Clear, Dentona Flexisplint, Cosmos Bite Splint, and ProArt Print Splint), one milled (ProArt CAD Splint), and one cold-polymerized (ProBase Cold) occlusal splint materials were used to determine flexural strength and surface hardness values. The three-point flexure test was used for the determination of flexural strength values, while Vickers hardness was measured to determine surface hardness. Ten specimens (n = 10) of each material were tested using these procedures. One-way ANOVA and Tukey’s post-hoc test were used to analyze the obtained results (α = 0.05). The values of flexural strength ranged from 46.1 ± 8.2 MPa to 106 ± 8.3 MPa. The Vickers hardness values ranged from 4.9 ± 0.5 VHN to 20.6 ± 1.3 VHN. Significant differences were found among the tested materials (p < 0.0001). The milled and cold-polymerized materials yielded higher values for both flexural strength (only one 3D-printed resin had comparable results to cold-polymerized acrylics) and surface hardness. There are differences in the mechanical properties of the various tested occlusal splint materials. The flexural strength of most of the 3D-printed materials and their surface hardness values are still inferior when compared to the milled or cold-polymerized materials.
... The study conducted by Ohara et al. in 2022 aimed to assess patient satisfaction with conventional dentures (CDs) compared to 3D printed digital dentures (DDs). The results indicate that while patient satisfaction with DDs may be slightly lower than that with CDs in terms of phonetics, ease of cleaning, stability, comfort, and overall satisfaction, a significant portion of patients (20%) preferred and utilized DDs fabricated using 3D printing due to reduced social disability and fewer clinic visits [101,142]. ...
The intensive development of technologies related to human health in recent years has caused a real revolution. The transition from conventional medicine to personalized medicine, largely driven by bioprinting, is expected to have a significant positive impact on a patient’s quality of life. This article aims to conduct a systematic review of bioprinting’s potential impact on health-related quality of life. A literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive literature search was undertaken using the PubMed, Scopus, Google Scholar, and ScienceDirect databases between 2019 and 2023. We have identified some of the most significant potential benefits of bioprinting to improve the patient’s quality of life: personalized part production; saving millions of lives; reducing rejection risks after transplantation; accelerating the process of skin tissue regeneration; homocellular tissue model generation; precise fabrication process with accurate specifications; and eliminating the need for organs donor, and thus reducing patient waiting time. In addition, these advances in bioprinting have the potential to greatly benefit cancer treatment and other research, offering medical solutions tailored to each individual patient that could increase the patient’s chance of survival and significantly improve their overall well-being. Although some of these advancements are still in the research stage, the encouraging results from scientific studies suggest that they are on the verge of being integrated into personalized patient treatment. The progress in bioprinting has the power to revolutionize medicine and healthcare, promising to have a profound impact on improving the quality of life and potentially transforming the field of medicine and healthcare.
... This technique uses a scanning laser to build parts one layer at a time using light-cured photopolymer resin. The advantage of this method is the possibility to produce high-resolution objects and create complex shapes with undercuts, such as dental devices [41,42]. This technology also does not involve complex material preparation for the printable inks or complex post-treatment of printed appliances. ...
Custom mouthguards are used in various sports disciplines as a protection for teeth, temporomandibular joints, and soft tissues of the oral cavity from impact forces. The purpose of this research was to evaluate the mechanical properties of flexible polymeric 3D-printable materials and to select a material with the most favourable physical properties for making intraoral protectors. Four 3D-printable polymeric materials were selected for the evaluation: IMPRIMO LC IBT (Scheu-Dental, Iserlohn, Germany), Keyortho IBT (EnvisionTEC, Gladbeck, Germany), IBT (Formlabs, Somerville, MA, USA), and Ortho IBT (NextDent, Utrecht, Netherlands). A total of 176 samples (44 from each material) was 3D-printed using the stereolitography (SLA) technique. Tensile strength, flexural strength, notch-toughness, Shore hardness, sorption, and solubility tests were conducted. The materials were compared using a series of analyses of variance (one-way ANOVA) with Bonferroni post hoc tests. Statistical analyses were performed with the use of IBM SPSS Statistics 28.0.0 software (IBM, New York, NY, USA). Each material was assigned a score from 1 to 4 depending on the individual test results, and tests were given indexes according to the significance of the parameter in the mouthguard protective function. The number of points obtained by each material in each test was then multiplied by the test index, and the results were tabulated. The material with the highest result among the ones studied-most suitable for the application in mouthguard fabrication-was Keyortho IBT from EnvisionTEC.
... All over the world, the digital solutions of 3D printing and their popularisation are helping teaching units and hospitals to achieve digital transformation in an effective and efficient way, of which this book and the chapter dedicated to education is a good example. Furthermore, in dentistry and facial areas close to the oral cavity, this technique is widely used in head and neck surgery (craniofacial and orthognathic implants), personalised oral soft tissue regeneration, orthopaedics (fracture printing in orthopaedic trauma surgery, 3D imaging), 3D printing and virtual 3D planning in endodontics, ophthalmology, template printing in mandibular (and surgical) reconstruction, prosthodontics (replication techniques for making e.g., digital dentures and overdentures, also on implants), periodontal regeneration and repair (periodontal implants), orthognathic surgery, 3D physical models of teeth, printing of bone implants and virtual endoscopy, as well as in autotransplantation [8][9][10][11][12][13][14][15]. ...
Making use of 3D-printed teeth models in teaching students offers an innovative approach. Empowering a highly efficient digital science to improve teaching. This gives opportunity to learn and enable intuitive dentist and student-patient communication. Clear and engaged satisfactory experience for teacher, student and patient. Thanks to the perfect representation of teeth anatomy, making use of 3D models in the teaching of endodontics may well be recommended as holding substantial potential in improving overall quality of training at the preclinical stage, with a view to appreciably reducing overall risk of encountering complications during the actual clinical work. The mistakes made by the students, for example, at the access cavity for root canal treatment stage were assessed with the help of 3D models, as well as their overall, hands-on learning progress was evaluated. Also in the clinical process, before the procedure with the participation of a patient, a student or a specialist may perform a treatment procedure on a tooth printed in 3D, based on tomography, under the supervision of an experienced specialist. 3D printing digital solutions and the popularization of these solutions around the globe are helping dental clinics and hospitals to effectively and efficiently achieve digital transformation.
... Since it is more complex to make changes at this point compared to the traditional technique, the cardinal indication of the printing procedure remains for the edentulous rehabilitation that starts from the copy of the patient's pre-existing denture or teeth (preextractive denture) (69). Regarding the 3D printers, additive production is a manufacturing process that allows to create physical objects starting from a digital model. ...
Aim The aim of the present study is to review the literature evaluating the main steps required in complete denture rehabilitation in case of edentulous jaws in the digital workflow. Methods This review was conducted using PubMed and Scopus databases. It focuses on the following clinical and laboratory steps: the impression, the registration of the centric relation, the try-in and the finalization. Results According to the reported data in literature, impression, try-in and finalization are feasible with a complete digital approach. Registration of the centric is possible only combining the digital with the traditional one. Digital impression is accurate, but shows some limitations in the peripheral areas. The printing process, because of accuracy and its cost, can be used for the try-in of the prototype. Milling machine is more accurate than 3D printing and offers a good level of retention and of satisfaction for the patient. Conclusions In relation to optical scanning, there are still some limitations because of the impossibility to perform selective pressure in the areas of the peripheral seal. Fully digital methods to register the centric are not described. More evidence based evidence on qualitative and quantitative results is required to validate digital denture protocols.
... Similarly, previous authors have reported similar workflows for prosthetically driven computer-aided implant planning and fabricating milled screw-interim dental restorations; however, the 3D facial references were not incorporated. 18,31 The accuracy of the described technique should be evaluated to assess any distortion in the workflow during data acquisition, virtual alignment, and manufacturing of the dental devices. ...
A technique is described to create a virtual 3-dimensional representation of an edentulous patient by aligning the facial, intraoral, and cone beam computed tomography scans guided by an additively manufactured scan body. Having the virtual patient facilitated the prosthetically driven implant planning, the additive manufacturing of the surgical implant guides, and the interim dental restorations.
... CDs can be produced using an additive (3D printing) or subtractive (milling) process. The most commonly used method at present is the subtractive method [10][11][12][13]. In the subtractive method, the prostheses are milled from proprietary resin discs that are polymerized under high pressure and high temperature [14]. ...
At present, complete dentures (CDs) remain the only treatment available for the majority of edentulous patients. CDs are primarily fabricated using a conventional method using polymethylmethacrylate (PMMA) resin. The steps involved in PMMA polymerisation directly affect the quality of the resin prosthetic base and any error reduces retention and occlusal accuracy of CDs. Furthermore, when using the conventional technique, the residual monomer alters the resin mechanical properties and may cause mucosal reactions. Recently, computer aided design and computer aided manufacture (CAD/CAM) techniques were increasingly used to fabricate CDs by machining resin discs that have been manufactured under high pressure and temperature. This systematic review compares CAD/CAM and conventional CDs according to their mechanical, physical and chemical characteristics, as well as the clinical impact of any differences between them. A review was conducted according to the preferred reporting items for systematic reviews and meta-analyses checklist on 392 publications from both PubMed and backward research. Fifteen studies have been included. Results showed that CAD/CAM resins had globally better physical and mechanical properties than conventional resins. The use of machined resin could improve the clinical performance, maintenance and longevity of CDs. Further studies in clinical use would be required to complement these results.
... The relined trial denture was then digitized, teeth set-up was adjusted based on the evaluation, and the final prostheses were printed. Similarly, other authors have mainly recommended scanning the existing maxillary and mandibular CRDPs, 3D printing them, and using them as a custom tray [42][43][44] or trial dentures [45] for conventional workflow. ...
Background
The purpose of this paper is to review the available literature on three-dimensionally printed complete dentures in terms of novel biomaterials, fabrication techniques and workflow, clinical performance and patient satisfaction.
Methods
The methodology included applying a search strategy, defining inclusion and exclusion criteria, selecting studies and forming tables to summarize the results. Searches of PubMed, Scopus, and Embase databases were performed independently by two reviewers to gather literature published between 2010 and 2020.
Results
A total of 126 titles were obtained from the electronic database, and the application of exclusion criteria resulted in the identification of 21 articles pertaining to printed technology for complete dentures. Current innovations and developments in digital dentistry have successfully led to the fabrication of removable dental prostheses using CAD/CAM technologies. Milled dentures have been studied more than 3D printed ones in the currently available literature. The limited number of clinical studies, mainly case reports, suggest current indications of 3D printing in denture fabrication process to be custom tray, record bases, trial, interim or immediate dentures but not definitive prostheses fabrication. Limitations include poor esthetics and retention, inability to balance occlusion and low printer resolution.
Conclusions
Initial studies on digital dentures have shown promising short-term clinical performance, positive patient-related results and reasonable cost-effectiveness. 3D printing has potential to modernize and streamline the denture fabrication techniques, materials and workflows. However, more research is required on the existing and developing materials and printers to allow for advancement and increase its application in removable prosthodontics.
... The advantage of this method is that it is possible to produce transparent objects and create large, high-resolution models. Furthermore, by setting detailed parameters such as the print pitch, it is possible to form complex shapes with undercuts that are difficult to shear, and further applications in the dental field are expected [19]. ...
This study evaluated the effects of the differences in the printing directions of stereolithography (SLA) three-dimensional (3D)-printed dentures on accuracy (trueness and precision). The maxillary denture was designed using computer-aided design (CAD) software with an STL file (master data) as the output. Three different printing directions (0°, 45°, and 90°) were used. Photopolymer resin was 3D-printed (n = 6/group). After scanning all dentures, the scanning data were saved/output as STL files (experimental data). For trueness, the experimental data were superimposed on the master data sets. For precision, the experimental data were selected from six dentures with three different printing directions and superimposed. The root mean square error (RMSE) and color map data were obtained using a deviation analysis. The averages of the RMSE values of trueness and precision at 0°, 45°, and 90° were statistically compared. The RMSE of trueness and precision were lowest at 45°, followed by 90°; the highest occurred at 0°. The RMSE of trueness and precision were significantly different among all printing directions (p < 0.05). The highest trueness and precision and the most favorable surface adaptation occurred when the printing direction was 45°; therefore, this may be the most effective direction for manufacturing SLA 3D-printed dentures.
... 7-9 A desktop scanner, however, provides better dimensional accuracy than intraoral scanners. 10 Although desktop scanners are available that allow 360-degree scanning of a complete denture, 11 most current desktop scanners can only scan about two-thirds of the complete denture at a time. The intaglio and cameo surfaces can be scanned to yield 2 separate scans that overlap over one-third of their surface areas. ...
This article describes a digital technique for obtaining a standard tessellation language (STL) file of a complete denture using a desktop scanner and open-source software. Accurate recording of the surface details of the denture in 3D was performed using a desktop scanner. The generated STL file from this technique represents a digital duplicate of the scanned denture. This file can be used for surgical implant placement planning, fabricating a duplicate denture, and storing the scanned denture as a digital file for future use.
Background/Aim
This study aims to evaluate and compare the impact absorption capacities of thermoformed ethylene vinyl acetate (EVA) mouthguards and 3D‐printed polyolefin mouthguards used in sports dentistry applications. The objective is to determine whether 3D‐printed polyolefin mouthguards offer superior impact toughness compared to traditional EVA mouthguards commonly used in sports settings.
Materials and Methods
Six material samples were assessed: five pressure‐formed EVA mouthguards (PolyShok, Buffalo Dental, Erkoflex, Proform, and Drufosoft) and one 3D‐printed synthetic polymer (polyolefin). The materials were evaluated using a modified American Society for Testing and Materials (ASTM) D256 Test Method A for Izod pendulum impact resistance of plastics. Polyolefin samples were 3D‐printed using fused filament fabrication (FFF) technology. Notably, the FFF process included samples printed with notches placed either parallel or perpendicular to the build direction. This orientation served as a study factor, allowing for comparison of material behavior under different printing conditions. Impact testing was conducted using an Izod impact tester to assess the materials' performance under controlled impact conditions.
Results
The study achieved a high power (1.0) in power analysis, indicating strong sensitivity to detect significant differences. Among molded materials, PolyShok showed significantly lower impact toughness compared to others ( p = 0.06). The mean impact absorption of EVA materials was 5.4 ± 0.3 kJ/m ² , significantly lower than polyolefin materials, which demonstrated 12.9 ± 0.7 kJ/m ² and superior performance ( p = 0.0). Horizontal‐notched polyolefin samples exhibited higher impact strength compared to vertical‐notched samples ( p = 0.009).
Conclusions
3D‐printed polyolefin mouthguards exhibited significantly higher impact toughness than thermoformed EVA mouthguards. While EVA materials demonstrated structural robustness, their lower impact resistance and observed tearing in other test specimens suggest the need for alternative testing standards to better reflect real‐world conditions. 3D‐printed mouthguards fabricated with build orientations perpendicular to the direction of impact demonstrate significantly enhanced impact absorption. Further research into manufacturing methods and testing protocols is recommended to optimize mouthguard performance under impact scenarios.
of the study is to investigate the ultimate flexural strength and Young’s modulus of some materials, which can be used for complete denture fabrication by Masked stereolithography 3D printing technology.Three groups of five specimens each were fabricated. Two of the groups are 3D printed by Masked SLA 3D printer of two commonly used denture base resins. The third group is set to be a control as the specimens were fabricated of a heat-curing acrylic resin. A three-point flexural test tested the objects, and the data collected was used to determine ultimate flexural strength and Young’s modulus calculation. All the results are compared to the ISO Standard 20795-1.The data shows that the mean ultimate flexural strength of the 3D printed specimens is 87 MPa - 89 MPa. Their results are very similar to those for the heat-curing acrylic resin, which means the ultimate flexural strength is 93 MPa. The mean Young’s modulus obtained for the first group of 3D printed specimens is 2263.21 MPa and 2377.44 MPa for the second one. As for the control group, 2396.06 MPa is achieved. When ISO Standard 20795-1 is inspected, all the data obtained covers the minimum requirements.The limitations of the study concern to some additional factors that should be observed for more detailed evaluation. For example, the level of the final polymerization of light-curing resins for 3D printing, their ability to washstand to different defect and denture-bearing area characteristics (the notch for the labial and buccal frenulum, chambers for torus release, etc.), the ability of the materials to withstand to cyclic load, etc.3D printing is faster and cheaper than conventional methods for complete denture fabrication. The knowledge about the mechanical properties of the different materials for 3D printing is very valuable for properly selecting a material and approach for complete denture fabrication.Nowadays, 3D printing is essential in dentistry. For this reason, observation and knowledge of the raw materials properties is very important for the proper choice of a material and/or technology for each clinical case.
Purpose of review- This review provides insight into the current techniques and systems used for fabricating digital dentures. Recent Findings - In the current era of digitalization, innovations in the field of digital dentistry have led to significant advancements in complete denture fabrication. Digital technologies may revolutionize the future of dentistry in terms of simplicity and treatment time. Complete dentures fabricated with the help of a computer-aided design and manufacturing have become increasingly popular as they result in better fit, and high patient and dentist satisfaction while reducing the number of appointments. Summary- This review focuses on different techniques and digital workflow for digital complete denture fabrication.
Teknolojinin ilerlemesi ile dijitalizasyon hayatımızın her alanında etkili olmaktadır. Diş hekimliğinde de diş ve çevre dokulara en yakın materyal ve yöntem arayışı devam etmekte ve buna bağlı olarak yeni materyallerin geliştirmesi ve kullanıma sunulması son yıllarda hızla artmaktadır. Üç boyutlu (3B) baskı yöntemi de zaman ve maliyet kazandırma potansiyeli açısından son yıllarda diş hekimliğinin birçok branşında kullanımı yaygınlaşan bir yöntemdir. Bu üretim prosedüründe bazı aşamaların kalkması daha yüksek hassasiyet ile karmaşık protez modellerinin elde edilmesini sağlamaktadır. Özellikle Protetik Diş Tedavisi alanında cazip hale gelen bu yöntem ve kullanılan materyallerle ilgili yeterli bilgi bulunmamaktadır ve yaygın bir şeklide bilimsel çalışmalar yapılmaya devam etmektedir. Bu derlemede üç boyutlu baskı yöntemleri ve özellikle bu yöntemler ile hazırlanan hareketli protez kaide materyallerinin fiziksel ve mekanik özellikleri anlatılmıştır.
This clinical report describes a fully digital workflow for replicating removable partial dentures (RPDs). The artificial teeth and denture base of existing dentures were duplicated and applied to new dentures with a redesigned framework. After the components of RPDs had been separated from the scan data of the existing dentures, they were fabricated using 3-dimensional printing and assembled to create a new denture.
The current paper aims to present a new casting approach in dentistry by eliminating some conventional preliminary procedures and digitalising the process as much as possible.The experiment uses six digital crown patterns. They are aligned with each other and to the wall of a virtual casting ring. Then a digital sprue system is created. The object alignment and sizes are revised, and the optimal correlation is set. Finally, a single virtual object is created and is 3D printed of light curing acrylic resin suitable for casting, invested, and cast.The castings that are achieved have good quality and no defects. At the same time, the virtual designing and aligning of the patterns and all the components of the sprue system and casting ring save much time and allows better precision to be achieved. All these facts allow better control of the casting process results, making the process faster, more predictable, and more accurate.The limitations of this study concerns pattern selection. It is well-known that the acrylic resin sublimates and expands massively during a temperature rise, which may cause mould fracture. This obstacle is very representative as solid objects with higher volumes are examined. This may enforce alignment revision or even temperature rate modification.Suggested approach will be very useful for daily dental laboratory practice by optimizing the working time of the dental technician, making the denture production process faster, more predictable, and more accurate. As a result, the process optimizes the working process in dental offices, by allowing shortening the time of each visit and treatment plan terms.Presented approach reveals some new opportunities for dental technicians to substitute the conventional raw stages of sprue system fabrication with digital planning and designing. This allows dental technicians to take advantage of the full potential of digital technologies.
Purpose:
The strength of 3D-printed resins is affected by different factors, but review articles clarifying these factors are limited. This review lists the factors affecting the strength of 3D-printed resins and the possible correlations between them to answer the study question: what are the factors affecting the flexural strength of 3D-printed resins?
Methods:
A database search (PubMed, Google Scholar, and Scopus) was performed, limited to English-language publications between 2010 and February 1, 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used for study selection. The modified Consolidated Standards of Reporting Trials (CONSORT) checklist was used to determine the risk of bias of the included studies in this review. The data analysis was descriptive due to the presence of many variables in the included studies.
Results:
Out of 123 studies, 26 were reviewed for full-text analysis, and 19 met the inclusion criteria and were thus included in this systematic review. The included studies were divided according to the investigated resin: 5 studies tested provisional restorations, 7 tested denture base resins, 2 tested occlusal devices, 3 tested orthodontic appliances, 1 tested denture teeth, and 1 tested surgical guide resins. These studies investigated the flexural strength of 3D-printed resins, with different factors such as reinforcement with fillers or nanofillers; printing orientation, angulation, and directions; post-polymerization time and temperature; third-party printing (switching between printers and materials); printing layer thickness; and post-printing rinsing time. Most factors significantly affected the flexural strength of 3D-printed resin.
Conclusions:
The strength of 3D-printed resins could be improved with one or more of the following factors: filler or nanofiller addition; printing orientation, angulation, or directions; printing layer thickness; and post-polymerization time and temperature. However, further studies combining these factors are recommended. This article is protected by copyright. All rights reserved.
Additive manufacturing (AM) technologies build physical three‐dimensional (3D) geometries by a consecutive layer‐by‐layer addition of material. AM technologies can also produce 3D structures that can actively change their properties under environmental influences. When using subtractive or additive fabricating methods or computer‐aided design (CAD) and computer‐aided manufacturing procedures, the manufacturing workflow of a dental device starts with its virtual design, normally obtained using a dental or non‐dental CAD software program. In dentistry, vat‐polymerization, material jetting technologies, and material extrusion have been frequently used to process polymers and fabricate dental devices, such as dental casts, custom trays, silicone indexes, positioning guides for custom abutments, tooth preparation guides, interim dental restorations, removable prostheses, occlusal devices, and surgical guides. Powder bed fusion technologies are the most frequent metal AM technology used to manufacture cobalt–chromium and titanium frameworks in restorative dentistry.
The conventional method of fabricating implant-retained overdentures involves multiple steps and patient visits. However, the duplication of existing complete dentures could decrease the number of visits and increase patient satisfaction. An existing maxillary implant-retained overdenture was replaced for a 78-year-old man; the existing implant-retained overdenture and his face were scanned at the first visit. The scanned intaglio image was inverted to obtain a virtual maxillary cast and used to fabricate the metal framework of the replacement implant-retained overdenture. Prefabricated artificial teeth were arranged on a 3-dimensional trial denture created from the scan data of the existing implant-retained overdenture. The replacement implant-retained overdenture was fabricated on the metal framework by using the injection molding technique. By using these digital techniques, a stable and esthetic implant-retained overdenture was delivered in 2 visits.
This JPD Digital video presentation presents the clinical treatment from start to finish in which a dual-shaded bi-coloured monolithic disk was used for the fabrication of an immediate digital complete denture followed by the delivery of a definitive digital complete denture. The treatment plan included extraction of the remaining maxillary and mandibular teeth followed by an esthetic evaluation with digital smile design. The digital definitive complete dentures were milled from a monolithic dual-shaded disk.
This technique report presents a novel method of digitally replicating a treatment denture and converting it into a definitive denture. The procedure accurately duplicates the appearance of the mucosal surface and border of the treatment dentures, mounts the jaw relation on a virtual articulator to arrange artificial teeth, and optimizes the occlusion based on recorded mandibular motion tracks. This technique uses personalized jaw relation transfer and dynamic occlusal adjustment to establish balanced occlusion, which accomplishes the digital duplication of the treatment denture with high accuracy and minimal effort.
Fabrication of complete dentures using a 3D printer is quicker and more economic than conventional methods. However, the photopolymer resins used in 3D printers has a lower flexural strength than heat-cured resin. Furthermore, photopolymer resins exhibit anisotropic properties depending on the printing direction, but no studies have evaluated their mechanical properties. The impact of stress distribution caused by changing the printing direction of the 3D printed denture has not been clarified. This study aimed to investigate the effect of different printing directions (0°, 45°, and 90°) of stereolithography (SLA) 3D printed dentures on stress distribution. Artificial mucosa was fabricated to fit a maxillary edentulous model, which was scanned to generate a standard tessellation language (STL) file. Subsequently, the upper denture was designed using computer-aided design (CAD) software, output as an STL file (master data), and set in three different printing directions (0°, 45°, and 90°). It was printed by the SLA 3D printer using photopolymer resin (n=6, in each printing direction). The stress distributions of the dentures were monitored using four rosette strain gauges, which were cemented to the midline of each denture as follows: above the labial frenum (A), at the incisive papilla (B), at the endpoint of the denture (D), and at the mid-point of B and D (C). A load was applied to the posterior region at a loading rate of 20 N/s from 0 N to 200 N using a universal testing machine. Changes in the applied load and strain at each point were recorded. The maximum principal strain (MPS) and the direction of the MPS (θ) were calculated. Each mean MPS was compared using Kruskal–Wallis and Steel–Dwass multiple comparison tests (p < 0.05). The stress distribution showed that the MPS for 45° printing was the lowest at each measurement point except for A under 200 N loading. The MPS at C for 0° was significantly different from that at C for 45° and 90°. The MPS at D in all the printing directions showed significant differences. The MPS at B for 45° was significantly different from that at B for 90°. The MPS at A in all printing directions showed no significant difference. Within the limitations of this study, differences in printing direction affected the stress distribution of SLA 3D printed dentures. The results showed that the stress distribution of the denture printed at 45° by the 3D printer system was the smallest compared with dentures printed at 0° and 90°. These results suggest that a printing direction of 45° is preferable when fabricating dentures using a 3D printer in clinical setting.
Purpose
The introduction of computer‐aided design/computer‐aided manufacturing (CAD/CAM) technology to the field of removable prosthodontics has recently made it possible to fabricate complete dentures of prepolymerized polymethyl methacrylate (PMMA) blocks, which are claimed to be of better mechanical properties; however, no published reports that have evaluated mechanical properties of CAD/CAM PMMA. The purpose of this study was to compare flexural strength, impact strength, and flexural modulus of two brands of CAD/CAM PMMA and a conventional heat‐cured PMMA.
Materials and Methods
45 rectangular specimens (65 mm × 10 mm × 3 mm) were fabricated (15 CAD/CAM AvaDent PMMA specimens from AvaDent, 15 CAD/CAM Tizian PMMA specimens from Shütz Dental, 15 conventional Meliodent PMMA specimens from Heraeus Kulzer) and stored in distilled water at (37 ± 1°C) for 7 days. Specimens (N = 15) in each group were subjected to the three‐point bending test and impact strength test, employing the Charpy configuration on unnotched specimens. The morphology of the fractured specimens was studied under a scanning electron microscope (SEM). Statistical analysis was performed using one‐way ANOVA and Tukey pairwise multiple comparisons with 95% confidence interval.
Results
The Schütz Dental specimens showed the highest mean flexural strength (130.67 MPa) and impact strength (29.56 kg/m²). The highest mean flexural modulus was recorded in the AvaDent group (2519.6 MPa). The conventional heat‐cured group showed the lowest mean flexural strength (93.33 MPa), impact strength (14.756 kg/m²), and flexural modulus (2117.2 MPa). Differences in means of flexural properties between AvaDent and Schütz Dental specimens were not statistically significant (p > 0.05).
Conclusions
As CAD/CAM PMMA specimens exhibited improved flexural strength, flexural modulus, and impact strength in comparison to the conventional heat‐cured groups, CAD/CAM dentures are expected to be more durable. Different brands of CAD/CAM PMMA may have inherent variations in mechanical properties.
Intraoral scanning was used to capture the soft tissue surfaces of both maxillary and mandibular edentulous ridges and the denture borders. Additionally, an intraoral scanner was used to digitize existing dentures with their tooth positions and base forms and a centric relation record obtained with a Gothic arch-tracing device. These scans provided all the required records for fabrication of computer-aided design/computer-assisted manufacturing of complete dentures.
Background:
Three main properties are responsible for the microbial attractiveness of denture surfaces: roughness, hydrophilicity and free surface energy.
Objective:
This study investigated whether CAD/CAM-fabricated dentures are more favourable for these surface properties than conventionally fabricated dentures.
Methods:
The mucosal surface roughness of 54 standardised study dentures was measured using contact profilometry. The surface hydrophilicity and free surface energy of 70 standardised denture-resin specimens were determined by contact angle measurements. Both experimental settings compared AvaDent (AD), Baltic Denture System (BDS), Vita VIONIC (VV), Whole You Nexteeth (WN) and Wieland Digital Dentures (WDD) surfaces with conventionally manufactured denture surfaces (control group). The data were analysed using ANOVA together with Tukey's test or the Games-Howell post hoc test.
Results:
All CAD/CAM dentures had lower mean surface roughness values than conventional dentures. For AD, VV, WN and WDD, the differences were statistically significant. VV (p < .001), coated WN (p < .001), AD (p = .023) and BDS specimens (p = .027) were significantly more hydrophilic than the control group. All measured surface energies were of similar magnitude (mean values between 31.82 mJ/m2and 33.68 mJ/m2), and only coated WN specimens had a significantly increased mean value (66.62 mJ/m2, p < .001).
Conclusion:
Although most CAD/CAM dentures have smoother and more hydrophilic surfaces than conventional dentures, there is no difference in their free surface energy, except for coated dentures. This article is protected by copyright. All rights reserved.
Statement of problem:
Data comparing the denture tooth movement of computer-aided design and computer-aided manufacturing (CAD-CAM) and conventional denture processing techniques are lacking.
Purpose:
The purpose of this in vitro study was to compare the denture tooth movement of pack-and-press, fluid resin, injection, CAD-CAM-bonded, and CAD-CAM monolithic techniques for fabricating dentures to determine which process produces the most accurate and reproducible prosthesis.
Material and methods:
A total of 50 dentures were evaluated, 10 for each of the 5 groups. A master denture was fabricated and milled from prepolymerized poly(methyl methacrylate). For the conventional processing techniques (pack-and-press, fluid resin, and injection) a polyvinyl siloxane putty mold of the master denture was made in which denture teeth were placed and molten wax injected. The cameo surface of each wax-festooned denture was laser scanned, resulting in a standard tessellation language (STL) format file. The CAD-CAM dentures included 2 subgroups: CAD-CAM-bonded teeth in which the denture teeth were bonded into the milled denture base and CAD-CAM monolithic teeth in which the denture teeth were milled as part of the denture base. After all specimens had been fabricated, they were hydrated for 24 hours, and the cameo surface laser scanned. The preprocessing and postprocessing scan files of each denture were superimposed using surface-matching software. Measurements were made at 64 locations, allowing evaluation of denture tooth movement in a buccal, lingual, mesial-distal, and occlusal direction. The use of median and interquartile range values was used to assess accuracy and reproducibility. Levene and Kruskal-Wallis analyses of variance were used to evaluate differences between processing techniques (α=.05).
Results:
The CAD-CAM monolithic technique was the most accurate, followed by fluid resin, CAD-CAM-bonded, pack-and-press, and injection. CAD-CAM monolithic technique was the most reproducible, followed by pack-and-press, CAD-CAM-bonded, injection, and fluid resin. Techniques involving compression during processing showed increased positive occlusal tooth movement compared with techniques not involving compression.
Conclusions:
CAD-CAM monolithic dentures produced the best combination of accuracy and reproducibility of the tested techniques. The results from this study demonstrate that varying amounts of tooth movement can be expected depending on the processing technique. However, the clinical significance of these differences is unknown.
Recently, the use of computer-aided design/computer-aided manufacturing (CAD/CAM) to produce complete dentures has seen exponential growth in the dental market, and the number of commercially available CAD/CAM denture systems grows every year. The purpose of this article is to describe the clinical and laboratory procedures of 5 CAD/CAM denture systems.
Additive manufacturing or 3D printing is becoming an alternative to subtractive manufacturing or milling in the area of computer-aided manufacturing. Research on material for use in additive manufacturing is ongoing, and a wide variety of materials are being used or developed for use in dentistry. Some materials, however, such as cobalt chromium, still lack sufficient research to allow definite conclusions about the suitability of their use in clinical dental practice. Despite this, due to the wide variety of machines that use additive manufacturing, there is much more flexibility in the build material and geometry when building structures compared with subtractive manufacturing. Overall additive manufacturing produces little material waste and is energy efficient when compared to subtractive manufacturing, due to passivity and the additive layering nature of the build process. Such features make the technique suitable to be used with fabricating structures out of hard to handle materials such as cobalt chromium. The main limitations of this technology include the appearance of steps due to layering of material and difficulty in fabricating certain material generally used in dentistry for use in 3D printing such as ceramics. The current pace of technological development, however, promises exciting possibilities.
Statement of problem:
Currently no data comparing the denture base adaptation of CAD/CAM and conventional denture processing techniques have been reported.
Purpose:
The purpose of this in vitro study was to compare the denture base adaptation of pack and press, pour, injection, and CAD/CAM techniques for fabricating dentures to determine which process produces the most accurate and reproducible adaptation.
Material and methods:
A definitive cast was duplicated to create 40 gypsum casts that were laser scanned before any fabrication procedures were initiated. A master denture was made using the CAD/CAM process and was then used to create a putty mold for the fabrication of 30 standardized wax festooned dentures, 10 for each of the conventional processing techniques (pack and press, pour, injection). Scan files from 10 casts were sent to Global Dental Science, LLC for fabrication of the CAD/CAM test specimens. After specimens for each of the 4 techniques had been fabricated, they were hydrated for 24 hours and the intaglio surface laser scanned. The scan file of each denture was superimposed on the scan file of the corresponding preprocessing cast using surface matching software. Measurements were made at 60 locations, providing evaluation of fit discrepancies at the following areas: apex of the denture border, 6 mm from the denture border, crest of the ridge, palate, and posterior palatal seal. The use of median and interquartile range was used to assess accuracy and reproducibility. The Levine and Kruskal-Wallis analysis of variance was used to evaluate differences between processing techniques at the 5 specified locations (α=.05).
Results:
The ranking of results based on median and interquartile range determined that the accuracy and reproducibility of the CAD/CAM technique was more consistently localized around zero at 3 of the 5 locations. Therefore, the CAD/CAM technique showed the best combination of accuracy and reproducibility among the tested fabrication techniques. The pack and press technique was more accurate at 2 of the 5 locations; however, its interquartile range (reproducibility) was the greatest of the 4 tested processing techniques. The pour technique was the most reproducible at 2 of the 5 locations; however, its accuracy was the lowest of the tested techniques.
Conclusions:
The CAD/CAM fabrication process was the most accurate and reproducible denture fabrication technique when compared with pack and press, pour, and injection denture base processing techniques.
The aim of this review was to investigate usage of computer-aided design/computer-aided manufacture (CAD/CAM) such as milling and rapid prototyping (RP) technologies for removable denture fabrication. An electronic search was conducted in the PubMed/MEDLINE, ScienceDirect, Google Scholar, and Web of Science databases. Databases were searched from 1987 to 2014. The search was performed using a variety of keywords including CAD/CAM, complete/partial dentures, RP, rapid manufacturing, digitally designed, milled, computerized, and machined. The identified developments (in chronological order), techniques, advantages, and disadvantages of CAD/CAM and RP for removable denture fabrication are summarized. Using a variety of keywords and aiming to find the topic, 78 publications were initially searched. For the main topic, the abstract of these 78 articles were scanned, and 52 publications were selected for reading in detail. Full-text of these articles was gained and searched in detail. Totally, 40 articles that discussed the techniques, advantages, and disadvantages of CAD/ CAM and RP for removable denture fabrication and the articles were incorporated in this review. Totally, 16 of the papers summarized in the table. Following review of all relevant publications, it can be concluded that current innovations and technological developments of CAD/CAM and RP allow the digitally planning and manufacturing of removable dentures from start to finish. As a result according to the literature review CAD/CAM techniques and supportive maxillomandibular relationship transfer devices are growing fast. In the close future, fabricating removable dentures will become medical informatics instead of needing a technical staff and procedures. However the methods have several limitations for now.
The use of computer-aided design and computer-aided manufacturing (CAD/CAM) has become available for complete dentures through the AvaDent and Dentca systems. AvaDent uses laser scanning and computer technology. Teeth are arranged and bases formed using proprietary software.The bases are milled from prepolymerized pucks of resin. Dentca uses computer software to produce virtual maxillary and mandibular edentulous ridges, arrange the teeth and form bases. The dentures are fabricated using a conventional processing technique.
The aim of this study was to assess the effect of high-pressure polymerization on mechanical properties of denture base resin. A heat-curing denture base resin and an experimental PMMA were polymerized under 500MPa of pressure by means of an isostatic pressurization machine at 70°C for 24h to make rectangular specimens whose dimensions were 30mm×2mm×2mm. Each specimen was deflected on a three-point flexural test until either fracture occurred or the sample was loaded up to 8mm in deflection. The molecular weight of the PMMA without filler was analyzed using the high-speed liquid chromatography system. Increased ductility without fracture was shown in the specimens subjected to high pressure, while most of the control specimens (ambient pressure) fractured. The mean toughness of the PMMA specimens polymerized under the high pressure was significantly higher than the same material polymerized under ambient pressure (p<0.01). The high pressure groups of the denture resin and the PMMA revealed a significantly lower mean 0.2% yield stress, flexural strength, and elastic modulus than control groups (p<0.01). There were certain amounts of higher molecular weight polymers in the high pressure specimens than were present in the controls. The increased toughness shown in the PMMA polymerized under the high pressure was presumably attributed to the higher molecular weight produced by the pressure. The result suggests a potential application of the high-pressure polymerization to the development of PMMA-based denture resin with improved fracture resistance.
The purpose of this study was to evaluate the fabrication of a complete denture using a CAD/CAM system. Cone beam CT was used to measure the complete denture and the artificial teeth. After a 3D complete denture image was structured using 3D CAD software, we factored out the artificial teeth and obtained a 3D denture base image. A machining center cut an acrylic resin block, and fabricated an acrylic complete denture base. The artificial teeth were bonded to the cut denture base using resin cement. A 3D digitizer digitized the fabricated acrylic denture. We measured the deviations between the master 3D complete denture image and the 3D data of the fabricated acrylic denture. The average deviations from the master 3D image were 0.50 mm for the occlusal surface. This present study indicates that it is possible to fabricate a complete denture using a CAD/CAM system.
The purpose of this study was to duplicate the shapes of complete dentures by using a computer-aided design/manufacturing (CAD/CAM) system. The shapes of the complete dentures of an edentulous patient were measured using a non-contact type shape measurement system and morphological data at the interval of 0.25 mm were obtained in the X-axis and Y-axis directions. Measurement was performed from the occlusal surface and mucosal surface sides. Based on the three-dimensional morphological data, cutter paths for cutting were generated. For cutting, the three-step method consisting of rough cutting, finish cutting, and partial finish cutting was used and for duplicating the dentures the modelling wax was cut using a computerized numerical control (CNC) processor and ball-end mills with diameters of 6 mm and 1 mm. The method for the controlling of three axes (X, Y, and Z) of CNC machine was used, and cutting was performed only from two directions. Although further improvements are needed in the measurement and cutting in acute slope areas, the duplication of complete dentures appears to be possible using the CAD/CAM system.
Due to changes in the amount of curriculum time available for teaching complete denture construction to undergraduate students, course content requires reconsideration and possible modification. The idea that a replica complete denture technique may offer some advantages is explored. A review of the relevant literature fails to support many of the claimed benefits of this technique such as relative ease of adaptation by the elderly to new dentures. This article suggests that the replica denture technique should be considered as no more than an alternative method of making dentures. The relative demerits of the technique are discussed. A modification of the replica block technique to include important aspects of conventional complete denture courses is described. It is suggested that, because less clinical time is required, it may be a suitable way of introducing students to complete denture construction and educating them to a level which would encourage some to take further postgraduate study and would allow all graduates to treat routine cases or diagnose, treatment plan and refer to clinical dental technicians.
This study compared the biocompatibility, mechanical properties, and surface roughness of a pre-polymerized polymethyl methacrylate (PMMA) resin for CAD/CAM complete removable dental prostheses (CRDPs) and a traditional heat-polymerized PMMA resin. Two groups of resin substrates [Control (RC): conventional PMMA; Test (RA): CAD/CAM PMMA] were fabricated. Human primary osteoblasts and mouse embryonic- broblasts were cultured for biocompatibility assays. Mechanical properties and surface roughness were compared. ANOVA revealed no difference between the resin groups in the biocompatibility assays. RA demonstrated a higher elastic modulus (p=0.002), young’s modulus (p=0.002), plastic energy (p=0.002), ultimate strength (p=0.0004), yield point (p=0.016), strain at yield point (p=0.037), and toughness (p<0.0001); while RC displayed a higher elastic energy (p<0.0001). Laser profilometry concluded a rougher surface profile (p<0.0001) for RA. This study concluded that the tested CAD/CAM resin was equally biocompatible and presented with improved mechanical properties than the traditional heat-polymerized PMMA resin used in the fabrication of CRDPs.
Purpose:
The aim of this article was to critically review the current application of additive manufacturing (AM)/3D-printing techniques in prosthodontics and to highlight the influence of various technical factors involved in different AM technologies.
Materials and methods:
A standard approach of searching MEDLINE, EMBASE, and Google Scholar databases was followed. The following search terms were used: (Prosth* OR Restoration) AND (Prototype OR Additive Manufacture* OR Compute* OR 3D-print* OR CAD/CAM) AND (Dentistry OR Dental). Hand searching the reference lists of the included articles and personal connections revealed additional relevant articles. Selection criteria were any article written in English and reporting on the application of AM in prosthodontics from 1990 to February 2016.
Results:
From a total of 4,290 articles identified, 33 were seen as relevant. Of these, 3 were narrative reviews, 18 were in vitro studies, and 12 were clinical in vivo studies. Different AM technologies are applied in prosthodontics, directly and indirectly for the fabrication of fixed metal copings, metal frameworks for removable partial dentures, and plastic mock-ups and resin patterns for further conventional metal castings. Technical factors involved in different AM techniques influence the overall quality, the mechanical properties of the printed parts, and the total cost and manufacturing time.
Conclusion:
AM is promising and offers new possibilities in the field of prosthodontics, though its application is still limited. An understanding of these limitations and of developments in material science is crucial prior to considering AM as an acceptable method for the fabrication of dental prostheses.
Few studies have reported the application of digital technology to removable dentures, particularly for the process of impression and interocclusal recording for complete denture fabrication. This article describes a part-digitizing system of impression and interocclusal records for complete denture fabrication. The denture foundation area in an edentulous mouth, including the border areas and residual ridge, is outlined by tracing the surfaces with a 3-D pen-type digitizer. Specialized trays for final impressions and interocclusal records were generated using computer-aided design and manufactured using the digital data. Final impression and interocclusal records were carried out using these specialized trays. The computer-aided method using preliminary digital impressions and specialized trays would be feasible for clinical use for complete denture fabrication.
Conventional complete denture prosthetics require several appointments to register the maxillomandibular relationship and evaluate the esthetics. The fabrication of milled complete dental prostheses with digital scanning technology may decrease the number of appointments. The step-by-step method necessary to obtain impressions, maxillomandibular relation records, and anterior tooth position with an anatomic measuring device is described. The technique allows the generation of a virtual denture, which is milled to exact specifications without the use of conventional stone casts, flasking, or processing techniques.
Computer-aided technology is an emerging method for fabricating complete dentures. Consolidated information about historical background, current status, and scope for the future is lacking.
The purpose of this systematic review was to analyze the existing literature on computer-aided technology for fabricating complete dentures and provide the reader with a historical background, current status, and future perspectives on this emerging technology.
An electronic search of the English language literature between the periods of January 1957 and June 2012 was performed by using PubMed/MEDLINE with the following specific search terms: CAD-CAM complete dentures, digital complete dentures, computer dentures, designed dentures, machined dentures, manufactured dentures, milled dentures, and rapid prototyping dentures. Additionally, the search terms were used on the Google search engine to identify current commercial manufacturers and their protocols.
A total of 1584 English language titles were obtained from the electronic database, and the systematic application of exclusion criteria resulted in the identification of 8 articles pertaining to computer-aided technology for complete dentures. Since the first published report in 1994, multiple authors have described different theoretical models and protocols for fabricating complete dentures with computer-aided technology. Although no clinical trials or clinical reports were identified in the scientific literature, the Google search engine identified 2 commercial manufacturers in the United States currently fabricating complete dentures with computer-aided design and computer-aided manufacturing (CAD/CAM) technology for clinicians world-wide. These manufacturers have definitive protocols in place and offer exclusive dental materials, techniques, and laboratory support. Their protocols contrast with conventional paradigms for fabricating complete dentures and allow the fabrication of complete dentures in 2 clinical appointments.
A body of scientific literature related to computer-aided technology for complete dentures is emerging. Significant advancements in this technology have now resulted in their commercial availability with shorter clinical protocols. However, prospective clinical trials with true clinical endpoints are necessary to validate this technology. This could affect dental education, patient care, research, and public health worldwide.
Providing complete denture therapy to patients with atrophic residual alveolar ridges is challenging. Because these patients suffer ongoing diminution of the denture foundation, modern approaches often involve dental implant therapy as a means of improving the denture foundation and supplementing the mechanics of prosthesis support, retention, and stability. Regardless of implant availability, physiologically optimal denture contours and physiologically appropriate denture tooth arrangement should be achieved to maximize prosthesis stability, comfort, and function for patients. This article presents historical perspectives on the arrangement of denture teeth in the facial-lingual dimension and the contouring of complete denture polished surfaces. Additionally, a modern clinical technique is presented for the physiologic registration of denture tooth positions and denture base contours. Information gained may then be incorporated into definitive prostheses in an effort to achieve successful complete denture therapy.
Influence of CAD/CAM fabrication on denture surface properties.
- Steinmassl O.
- Dumfahrt H.
- Grunert I.
- Sterinmassl P.A.
A review of computer-aided design/computer-aided manufacture techniques for removable denture fabrication.
- Bilgin M.S.
- Baytaroğlu E.N.
- Erdem A.
- Diber E.
Trial of duplication procedure for complete dentures by CAD/CAM
- Kawahata