ArticlePDF Available

Abstract and Figures

Aim: The aim of this technical note is to present a computer-aided design-computer-aided manufacturing (CAD-CAM) surgical guide to perform a computer-guided bone biopsy. Traditionally, to diagnose abnormal conditions affecting jawbone, a bone biopsy is performed with the use of a trephine bur. The positioning of the bur, during the biopsy, is based on the skill of the surgeon; therefore, an inaccurate placement of a trephine bur may occur. The use of a guide, however, can minimize this risk and achieve a better result. Materials and methods: To determine the site and the extension of bone sampling, the stereolithography file (STL) file of cone-beam computed tomography (CBCT) images is acquired using a specific planning software and superimposed with the STL file of a dental cast; a virtual surgical guide is designed, using the same software that allows a 3D (three-dimensional) view of the guide from different perspectives and planes. The number and site of guide tubes are determined on the basis of the width and the extension of the sampling; thanks to a 3D printer, the surgical guide is manufactured. Results: The use of a customized surgical guide realized with CAD-CAM technology allows a precise and minimally invasive approach, with an accurate three-dimensional localization of the biopsy site. Conclusions: The high precision, great predictability, time-effectiveness and versatility of the present guide should encourage the clinician to use this minimally invasive surgical approach, but controlled clinical trials should be conducted to evaluate the advantages as well as any possible complications.
Content may be subject to copyright.
bioengineering
Technical Note
Computer-Guided Bone Biopsy: A Technical Note with the
Description of a Clinical Case
Federica Altieri 1, * , Giovanna Iezzi 2, Valeria Luzzi 1, Gianni Di Giorgio 1, Antonella Polimeni 1
and Michele Cassetta 1


Citation: Altieri, F.; Iezzi, G.; Luzzi,
V.; Di Giorgio, G.; Polimeni, A.;
Cassetta, M. Computer-Guided Bone
Biopsy: A Technical Note with the
Description of a Clinical Case.
Bioengineering 2021,8, 214.
https://doi.org/10.3390/
bioengineering8120214
Received: 19 November 2021
Accepted: 11 December 2021
Published: 15 December 2021
Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations.
Copyright: © 2021 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).
1Department of Oral and Maxillofacial Sciences, School of Dentistry, “Sapienza” University of Rome,
00100 Rome, Italy; valeria.luzzi@uniroma1.it (V.L.); gianni.digiorgio@uniroma1.it (G.D.G.);
antonella.polimeni@uniroma1.it (A.P.); michele.cassetta@uniroma1.it (M.C.)
2Department of Medical, Oral, Biotechnological Sciences, University “G. d’Annunzio” of Chieti-Pescara,
66100 Chieti, Italy; giovanna.iezzi@unich.it
*Correspondence: federica.altieri@uniroma1.it; Fax: +39-06-501-6612
Abstract:
Aim: The aim of this technical note is to present a computer-aided design–computer-aided
manufacturing (CAD–CAM) surgical guide to perform a computer-guided bone biopsy. Traditionally,
to diagnose abnormal conditions affecting jawbone, a bone biopsy is performed with the use of a
trephine bur. The positioning of the bur, during the biopsy, is based on the skill of the surgeon;
therefore, an inaccurate placement of a trephine bur may occur. The use of a guide, however, can
minimize this risk and achieve a better result. Materials and Methods: To determine the site and the
extension of bone sampling, the stereolithography file (STL) file of cone–beam computed tomography
(CBCT) images is acquired using a specific planning software and superimposed with the STL file
of a dental cast; a virtual surgical guide is designed, using the same software that allows a 3D
(three-dimensional) view of the guide from different perspectives and planes. The number and site
of guide tubes are determined on the basis of the width and the extension of the sampling; thanks to
a 3D printer, the surgical guide is manufactured. Results: The use of a customized surgical guide
realized with CAD–CAM technology allows a precise and minimally invasive approach, with an
accurate three-dimensional localization of the biopsy site. Conclusions: The high precision, great
predictability, time-effectiveness and versatility of the present guide should encourage the clinician
to use this minimally invasive surgical approach, but controlled clinical trials should be conducted to
evaluate the advantages as well as any possible complications.
Keywords: biopsy; computer-assisted surgery; CAD-CAM; CBCT; oral surgery; digital planning
1. Introduction
An accurate diagnosis and treatment of oral disease is an essential component of the
patient’s comprehensive dental care and the foundation of high-quality dentistry. Few
bony abnormalities can be accurately diagnosed based on their radiographic features [
1
].
Confirmatory diagnosis may require a biopsy and microscopic examination [
2
]. In current
dental practice, the reconstruction of cranial and maxillofacial defects is made through the
use of bone grafting. This is a surgical procedure that replaces missing bone with autolo-
gous bone, or with an artificial, synthetic, or natural substitute [
3
]. The most common use
of bone grafting is in implant-supported rehabilitation, in order to restore the edentulous
area of a missing tooth [
3
]. Once the transplanted bone is secured into its new location,
the blood supply is generally restored to the bone on which it is attached. To evaluate
the graft histology characteristics a bone biopsy is necessary [
2
]. Today, the most precise
imaging to perform a thorough evaluation of the maxillary bone structure is cone-beam
computed tomography (CBCT), which provides high spatial resolution, accessibility and a
lower radiation dosage compared to computed tomography (CT) [4,5].
Bioengineering 2021,8, 214. https://doi.org/10.3390/bioengineering8120214 https://www.mdpi.com/journal/bioengineering
Bioengineering 2021,8, 214 2 of 9
The aim of the present technical note is to describe a computer-aided design–computer-
aided manufacturing (CAD-CAM) surgical-guide procedure used to perform a bone biopsy
after a previous bone graft; a single case of guided bone biopsy with subsequent implant
insertion is described.
2. Materials and Methods
The present procedure, used at the Department of Oral and Maxillo-Facial Sciences
of “Sapienza” University of Rome, allows jawbone biopsy employing a surgical guide
realized with at least one tube that guides a trephine bur to enable accurate bone sam-
pling of the maxillary and/or mandibular bone. The realization of the present surgical
template requires:
The determining of bone sampling site and extension. For this purpose, DICOM
(Digital Imaging and Communications in Medicine) files of CBCT are acquired using
specific planning software and a superimposition of a 3D (three-dimensional) scan
of the cast model (Easy Optical3D Scanner, Open Technologies, Rezzato, BS, Italy) is
performed after uploading the corresponding STL file (stereolithography file);
The design of a virtual surgical guide through CAD software that allows a view of the
3D guide from different perspectives and planes; the number and site of guide tubes
are determined on the basis of the width and the extension of the sampling;
The surgical guide printing, thanks to a 3D printer (Stratasys OrhoDesktop, Eden
Praire, MN, USA).
3. Description of a Computer-Guided Biopsy
3.1. Manufacturing the Surgical Guide
In a young adult patient with the need for prosthetic rehabilitation of the maxillary
arch, due to multiple dental agenesis, the initial phase of treatment involved a split crest
procedure using autologous bone grafting. In order to achieve an adequate implant,
osseointegration and a successful treatment outcome from both functional and aesthetic
points of view are required, as is a good dental emergence profile. Equally, to obtain a
correct prosthetic rehabilitation [
6
] it is important to have at least 2 mm of width around
the implant bone crest at the buccal and palatal planes. Intra-oral tissues (mandibular
branch) or the extra-oral tissues (e.g., iliac crest bone) grafts usually led to good results,
but they are invasive and complications cannot be excluded, such as additional surgical
procedures [
6
]. To find an alternative solution in such cases, techniques for crest expansion
using bone expanders or osteotomes, or “split-crest” (SCT) performed with an ultrasound
device or with conventional surgery have been proposed [
7
]. The “split-crest” technique
consists of splitting the vestibular and oral cortical bones, displacing the vestibular cortical
bone in either the maxillary or mandible bone and separating it from the bone marrow and
creating a middle gap, which is usually occupied mostly by the inserted implants. The
space unoccupied by the implants can be filled with biomaterials such as autologous bone
grafts, particulate bone, or plasma derivatives, such as platelet-rich plasma [7].
The surgical sites were assessed by a clinical intraoral examination, panoramic and
periapical radiographs. The split crest criteria were used for the patient’s evaluation: (1) a
minimal horizontal bone width of 2 mm; (2) a minimal vertical bone height of 10 mm; (3) no
concavity in alveolar bone profile; and (4) the horizontal osteotomies had to end at least
1 mm distance from the neighboring teeth [
8
]. A CT was requested for a 3D pre-operative
evaluation to determine the presence of an alveolar width of at least 2 mm and the absence
of a concavity. A staged rehabilitation approach was planned given that the two-stage
ridge split usually has a higher implant success rate when the ridge width is lower than
5 mm after splitting [
9
]. After local anesthesia (Optocain
®
-Molteni Dental-Italia), a full
thickness crestal incision extended buccally and palatally was made with vertical divergent
releasing incisions extended into the vestibule. A mucoperiosteal flap was elevated, and
the bone ridge was exposed. The cortical bone was initially curetted, to remove all residual
connective tissue and periosteum, then, using a piezoelectric scalpel, a horizontal incision
Bioengineering 2021,8, 214 3 of 9
was made in the middle of the ridge with two releasing incisions, one mesial and one
distal. The horizontal osteotomies were performed at a distance of at least 1 mm from the
neighboring teeth. The alveolar ridge was split longitudinally in two parts, provoking a
greenstick fracture using a 4 mm straight osteotome (Hu-Friedy Mfg. Co., Chicago, IL,
USA). The straight osteotome was gently tapped on with a hammer to create a fine cut
longitudinal to the crest. The osteotome was then used as a lever to spread apart the two
cortical plates. The surgical fracture was extended to a depth of 10 mm. Many attempts
were made to avoid sharp and complete vertical or horizontal fractures of the buccal and
palatal bone plates. After a crestal incision, bone from the retromolar trigone was harvested
using a trephine (4
×
6 mm) and then fragmented into particles (bone chips). The bone
defect obtained by the separation of the bone segments was filled with bone chips, which
were condensed in the space between the buccal and palatal bone plates with the aim
of completely filling the space (Figure 1). The mucoperiosteal flap was sutured using
tension-free single sutures (GORE–TEX, W.L.Gore and Associates, Inc., Flagstaff, AZ, USA).
Suture removal was performed 10 days after the surgical procedure. A reduced implant
placement time approach in the staged rehabilitation was used [
10
]. After a healing period
of 2 months, a computer-guided implant surgery was carried out. During the computer-
guided procedure a bone graft sample was harvested thanks to a computer-guided biopsy
(Figure 2). A dedicated CAD software ( 3Shape Implant Studio
®
, Srl Milam, Italy ) was
used to plan the number, the length and the diameter of dental implants as well as the
dimensions of trephine bur to be used (Figure 3). A software application allowed the design
of the surgical guide (3Shape Implant Studio
®
) printed with a 3D printer (3D Stratasys
OrthoDesktop) (Figure 2A). In the present case two surgical guides were realized with
a total of 5 tubes. Since the diameter of the tubes is larger than that of the drills and the
implant, in some cases it is necessary to utilize two guides to hold two contiguous pipes.
Bioengineering 2021, 8, x FOR PEER REVIEW 3 of 9
connective tissue and periosteum, then, using a piezoelectric scalpel, a horizontal incision
was made in the middle of the ridge with two releasing incisions, one mesial and one
distal. The horizontal osteotomies were performed at a distance of at least 1 mm from the
neighboring teeth. The alveolar ridge was split longitudinally in two parts, provoking a
greenstick fracture using a 4 mm straight osteotome (Hu-Friedy Mfg. Co., Chicago, IL,
USA). The straight osteotome was gently tapped on with a hammer to create a fine cut
longitudinal to the crest. The osteotome was then used as a lever to spread apart the two
cortical plates. The surgical fracture was extended to a depth of 10 mm. Many attempts
were made to avoid sharp and complete vertical or horizontal fractures of the buccal and
palatal bone plates. After a crestal incision, bone from the retromolar trigone was har-
vested using a trephine (4 × 6 mm) and then fragmented into particles (bone chips). The
bone defect obtained by the separation of the bone segments was filled with bone chips,
which were condensed in the space between the buccal and palatal bone plates with the
aim of completely filling the space (Figure 1). The mucoperiosteal flap was sutured using
tension-free single sutures (GORE–TEX, W.L.Gore and Associates, Inc., Flagstaff, AZ,
USA). Suture removal was performed 10 days after the surgical procedure. A reduced
implant placement time approach in the staged rehabilitation was used [10]. After a heal-
ing period of 2 months, a computer-guided implant surgery was carried out. During the
computer-guided procedure a bone graft sample was harvested thanks to a computer-
guided biopsy (Figure 2). A dedicated CAD software ( 3Shape Implant Studio®, Srl Milam,
Italy ) was used to plan the number, the length and the diameter of dental implants as
well as the dimensions of trephine bur to be used (Figure 3). A software application al-
lowed the design of the surgical guide (3Shape Implant Studio®) printed with a 3D printer
(3D Stratasys OrthoDesktop) (Figure 2A). In the present case two surgical guides were
realized with a total of 5 tubes. Since the diameter of the tubes is larger than that of the
drills and the implant, in some cases it is necessary to utilize two guides to hold two con-
tiguous pipes.
Figure 1. (A) Bone harvest from the retromolar trigone with the use of a trephine (4 × 6 mm) bur;
(B) a detail of the bone sampling site; (C) the bone defect obtained by the separation of the bone
segments is filled with bone chips, which were condensed in the space between the buccal and pal-
atal bone plates with the aim of completely filling the space; (D) a detail of the bone graft.
Figure 1.
(
A
) Bone harvest from the retromolar trigone with the use of a trephine (4
×
6 mm) bur;
(
B
) a detail of the bone sampling site; (
C
) the bone defect obtained by the separation of the bone
segments is filled with bone chips, which were condensed in the space between the buccal and palatal
bone plates with the aim of completely filling the space; (D) a detail of the bone graft.
Bioengineering 2021,8, 214 4 of 9
Bioengineering 2021, 8, x FOR PEER REVIEW 4 of 9
It was not possible to design a single surgical guide due to the limited space in the
dental arch and the size of the tubes. The tubes guided the trephine bur as well as the
implants into their planned positions. Using dedicated sleeves of different diameters, it
was possible to guide, first, the trephine bur and then the implant drills and the implant
mounting devices. Bone cores were harvested using a 3.5 × 10 mm diameter trephine bur
under saline solution irrigation and processed for histology. Every guide had different
tubes called “master tubes” embedded within the acrylic resin surgical guide; the master
tubes had cylindrical walls and wings to prevent their rotation and to provide greater
mechanical strength. To adapt the master tube to the trephine bur, to the implant drills
and also to the mounting devices, removable sleeves were used. The removable sleeves
have a variable inner diameter that permits the accommodation of the biopsy trephine
bur, the implant drills, and the implant mounting devices.
The tooth-supported surgical guide was constructed with a 3D printer (3D Stratasys
OrthoDesktop).
Figure 2. (A) The tooth-supported surgical guide positioned in the upper arch; (B) a detail of the
biopsy trephine bur.
Figure 2.
(
A
) The tooth-supported surgical guide positioned in the upper arch; (
B
) a detail of the
biopsy trephine bur.
It was not possible to design a single surgical guide due to the limited space in the
dental arch and the size of the tubes. The tubes guided the trephine bur as well as the
implants into their planned positions. Using dedicated sleeves of different diameters, it
was possible to guide, first, the trephine bur and then the implant drills and the implant
mounting devices. Bone cores were harvested using a 3.5
×
10 mm diameter trephine bur
under saline solution irrigation and processed for histology. Every guide had different
tubes called “master tubes” embedded within the acrylic resin surgical guide; the master
tubes had cylindrical walls and wings to prevent their rotation and to provide greater
mechanical strength. To adapt the master tube to the trephine bur, to the implant drills and
also to the mounting devices, removable sleeves were used. The removable sleeves have a
variable inner diameter that permits the accommodation of the biopsy trephine bur, the
implant drills, and the implant mounting devices.
The tooth-supported surgical guide was constructed with a 3D printer (3D Stratasys
OrthoDesktop).
Bioengineering 2021,8, 214 5 of 9
Bioengineering 2021, 8, x FOR PEER REVIEW 5 of 9
Figure 3. (A) Virtual implant planning of 1.2 on the 3-Shape Implant Studio software; (B) planning
of implant position in the canine area [1.3].
3.2. Specimen Processing
A total of four bone cores, corresponding to the four implant sites planned in the
grafted bone tissue, were retrieved and immediately stored in 10% buffered formalin. The
specimens were processed using the Precise 1 Automated System (Assing, Rome, Italy).
The specimens were dehydrated in a graded series of ethanol rinses and embedded in a
glycolmethacrylate resin (Technovit, Kulzer, Wehrheim, Germany). After polymerization,
the specimens were sectioned, along their longitudinal axis, with a high-precision dia-
mond disk at about 150 lm and ground down to about 30 lm with a specially-designed
grinding machine. Two slides were obtained from each specimen. These slides were
stained with acid fuchsin and toluidine blue and examined with transmitted light Leitz
Laborlux microscope (Leitz, Wetzlar, Germany). Histomorphometry of the percentages of
newly formed bone, residual grafted material, and marrow spaces was carried out using
a light microscope (Leitz) connected to a high-resolution video camera (3CCD, JVC KY-
F55B, JVC, Yokohama, Japan) which interfaced with a monitor and PC (Intel Pentium III
1200 MMX, Intel, Santa Clara, CA, USA). This optical system was associated with a digit-
izing pad (Matrix Vision GmbH, Oppenweiler, Germany) and a histometry software pack-
age with image capturing capabilities (Image-Pro Plus 4.5; Media Cybernetics Inc., Im-
magini & Computer SncMilano, Italy).
Figure 3.
(
A
) Virtual implant planning of 1.2 on the 3-Shape Implant Studio software; (
B
) planning
of implant position in the canine area [1.3].
3.2. Specimen Processing
A total of four bone cores, corresponding to the four implant sites planned in the
grafted bone tissue, were retrieved and immediately stored in 10% buffered formalin. The
specimens were processed using the Precise 1 Automated System (Assing, Rome, Italy).
The specimens were dehydrated in a graded series of ethanol rinses and embedded in a
glycolmethacrylate resin (Technovit, Kulzer, Wehrheim, Germany). After polymerization,
the specimens were sectioned, along their longitudinal axis, with a high-precision diamond
disk at about 150 lm and ground down to about 30 lm with a specially-designed grind-
ing machine. Two slides were obtained from each specimen. These slides were stained
with acid fuchsin and toluidine blue and examined with transmitted light Leitz Laborlux
microscope (Leitz, Wetzlar, Germany). Histomorphometry of the percentages of newly
formed bone, residual grafted material, and marrow spaces was carried out using a light
microscope (Leitz) connected to a high-resolution video camera (3CCD, JVC KY-F55B, JVC,
Yokohama, Japan) which interfaced with a monitor and PC (Intel Pentium III 1200 MMX,
Intel, Santa Clara, CA, USA). This optical system was associated with a digitizing pad
(Matrix Vision GmbH, Oppenweiler, Germany) and a histometry software package with
image capturing capabilities (Image-Pro Plus 4.5; Media Cybernetics Inc., Immagini &
Computer SncMilano, Italy).
Bioengineering 2021,8, 214 6 of 9
3.3. Histological Results
At low magnification, trabecular bone with small and large marrow spaces was
observed (Figure 4). The coronal portion of the alveolar bone, after split crest, was evident.
In this portion the preexisting trabecular bone with small marrow spaces was in contact
to many remodeling and new bone formation areas. Moreover, some residual autologous
bone particles, which probably underwent a process of remodeling ending up in their
replacement with new bone, could be detected (Figure 5). Instead, the apical portion of the
bone core was characterized by newly trabecular bone and residual grafted particles, lined
by newly formed bone, which showed the features of a recently formed tissue, such as
wide osteocyte lacunae, high staining affinity, the presence of osteoblasts and the osteoid
matrix’s undergoing mineralization. In many areas the collagen matrix undergoing a
remodeling process was present. In the marrow spaces there were some blood vessels
close to the newly formed bone and the biomaterial particles (Figure 6). Inflammation and
multinucleated giant cells were absent. Histomorphometrical analysis showed that the
percentage of newly formed bone was 22.8%, marrow spaces 60.1% and residual grafted
material 17.1%.
Bioengineering 2021, 8, x FOR PEER REVIEW 6 of 9
3.3. Histological Results
At low magnification, trabecular bone with small and large marrow spaces was ob-
served (Figure 4). The coronal portion of the alveolar bone, after split crest, was evident.
In this portion the preexisting trabecular bone with small marrow spaces was in contact
to many remodeling and new bone formation areas. Moreover, some residual autologous
bone particles, which probably underwent a process of remodeling ending up in their
replacement with new bone, could be detected (Figure 5). Instead, the apical portion of
the bone core was characterized by newly trabecular bone and residual grafted particles,
lined by newly formed bone, which showed the features of a recently formed tissue, such
as wide osteocyte lacunae, high staining affinity, the presence of osteoblasts and the oste-
oid matrix's undergoing mineralization. In many areas the collagen matrix undergoing a
remodeling process was present. In the marrow spaces there were some blood vessels
close to the newly formed bone and the biomaterial particles (Figure 6). Inflammation and
multinucleated giant cells were absent. Histomorphometrical analysis showed that the
percentage of newly formed bone was 22.8%, marrow spaces 60.1% and residual grafted
material 17.1%.
Figure 4. At low magnification, two areas with different features are observed: the coronal one,
characterized by trabecular bone with small marrow spaces; and the apical, where autologous bone
particles surrounded by new bone can be seen (toluidine blue and acid fuchsin 9×).
Figure 4.
At low magnification, two areas with different features are observed: the coronal one,
characterized by trabecular bone with small marrow spaces; and the apical, where autologous bone
particles surrounded by new bone can be seen (toluidine blue and acid fuchsin 9×).
Bioengineering 2021,8, 214 7 of 9
Bioengineering 2021, 8, x FOR PEER REVIEW 7 of 9
Figure 5. Trabecular bone with small marrow spaces. In some areas bone particles undergoing remodeling process were
detected (toluidine blue and acid fuchsin 40×).
Figure 6. In the apical portion several residual biomaterial particles lined by new bone are found.
In the marrow spaces there are many blood vessels close to the newly formed bone and the bio-
material particles (toluidine blue and acid fuchsin 100×).
Figure 5.
Trabecular bone with small marrow spaces. In some areas bone particles undergoing
remodeling process were detected (toluidine blue and acid fuchsin 40×).
Bioengineering 2021, 8, x FOR PEER REVIEW 7 of 9
Figure 5. Trabecular bone with small marrow spaces. In some areas bone particles undergoing remodeling process were
detected (toluidine blue and acid fuchsin 40×).
Figure 6. In the apical portion several residual biomaterial particles lined by new bone are found.
In the marrow spaces there are many blood vessels close to the newly formed bone and the bio-
material particles (toluidine blue and acid fuchsin 100×).
Figure 6.
In the apical portion several residual biomaterial particles lined by new bone are found. In
the marrow spaces there are many blood vessels close to the newly formed bone and the biomaterial
particles (toluidine blue and acid fuchsin 100×).
Bioengineering 2021,8, 214 8 of 9
4. Discussion
Given the differences in treatment and prognosis for many bony entities, the iden-
tification of these lesions mandates biopsy. When radiological findings in the maxillary
and mandible bones require a histopathological examination for the correct diagnosis,
computer-guided biopsy can be used. Further treatment, if necessary, will then be dictated
by the definitive histopathologic diagnosis. The guide described in this note can be used for
many purposes: not only to guide the bone biopsy but also the implant site preparation and
the implant insertion [
11
]. This new technique allows both bone harvesting and implant
insertion to be performed at the same time. Bone sampling and subsequent histological
analysis allow us to evaluate the results obtained following bone regeneration. This tech-
nique can also be extremely useful in case of research aimed at comparing the images of a
CT or CBCT with the corresponding anatomical structure, allowing the clinician to obtain
a match between the radiological and the histological images. This technique can be used
even if no implants have to be inserted, i.e., it can be used to perform solely the biopsy. The
surgical guide can be tooth-, bone- or mucosa-supported.
The present computer-guided biopsy seems to have many advantages: a precise and
reliable biopsy sampling, a reduced surgical time, and safety of the anatomical structures.
As this procedure is flapless and minimally invasive, it reduces the post-operative discom-
fort; in addition, it is a safe method to prevent neurological damage in complex anatomical
regions with proximity to nerve branches. On the other hand, this procedure requires the
use of dedicated software and the construction of a surgical guide is expensive.
Moreover, considering the results of a recent study aimed to determine the presence
of a learning curve in static computer-assisted surgery (s-CAS), it would seem possible to
obtain predictable results in terms of accuracy from the beginning, using a CAD–CAM
surgical template. In fact, s-CAS it is not characterized by a typical “learning curve” [12].
5. Conclusions
In conclusion, the high precision, great predictability, time-effectiveness and versatility
of the present guide should encourage the clinical use of this minimally invasive surgical
approach, but controlled clinical trials should be conducted to evaluate the advantages of
the current method concerning treatment time and patient discomfort, as well as possible
complications.
Author Contributions:
F.A.: conception and design, acquisition of data, drafting and revising of
the manuscript; G.I.: performed the histological and manuscript final approval; V.L.: acquisition
of data, drafting and revising of the manuscript; G.D.G.: drafting and revising of the manuscript;
A.P.: revising of the manuscript and manuscript final approval; M.C.: conception and design
and manuscript final approval. All authors have read and agreed to the published version of
the manuscript.
Funding: This research received no external funding.
Institutional Review Board Statement:
The study was examined and approved by the Ethics Com-
mittee of the “Umberto I” Universital Hospital of Rome, Italy (protocol code: #4871 date of approval
05/02/2018).
Informed Consent Statement:
Patient consent was obtained to the treatment and to publish the
clinical intraoral photographs.
Data Availability Statement: The study did not report any data.
Conflicts of Interest: No conflict of interest.
Bioengineering 2021,8, 214 9 of 9
References
1.
Cassetta, M.; Altieri, F. The influence of mandibular third molar germectomy on the treatment time of impacted mandibular
second molars using brass wire: A prospective clinical pilot study. Int. J. Oral Maxillofac. Surg.
2017
,46, 905–911. [CrossRef]
[PubMed]
2.
Rosebush, M.S.; Anderson, K.M.; Rawal, S.Y.; Mincer, H.H.; Rawal, Y.B. The oral biopsy: Indications, techniques and special
considerations. J. Tenn. Dent. Assoc. 2010,90, 17–20. [PubMed]
3.
Cassetta, M.; Ricci, L.; Iezzi, G.; Dell’Aquila, D.; Piattelli, A.; Perrotti, V. Resonance frequency analysis of implants inserted with a
simultaneous grafting procedure: A 5-year follow-up study in man. Int. J. Periodontics Restor. Dent.
2012
,32, 581–589. [PubMed]
4.
Srivastava, K.C.; Shrivastava, D.; Austin, R.D. Journey towards the 3D dental imaging- the milestones in the advancement of
dental imaging. Int. J. Adv. Res. 2016,4, 377–382. [CrossRef]
5.
Jain, S.; Choudhary, K.; Nagi, R.; Shukla, S.; Kaur, N.; Grover, D. New evolution of cone-beam computed tomography in dentistry:
Combining digital technologies. Imaging. Sci. Dent. 2019,49, 179–190. [CrossRef] [PubMed]
6.
Slagter, K.W.; Hartog, L.; Bakker, N.A. Immediate placement of dental implants in the esthetic zone: A systematic review and
pooled analysis. J. Periodontol. 2014,85, e241–e250. [CrossRef] [PubMed]
7.
Simion, M.; Baldoni, M.; Zaffe, D. Jawbone enlargement using immediate implant placement associated with a split-crest
technique and guided tissue regeneration. Int. J. Periodontics Restor. Dent. 1992,12, 462–473. [PubMed]
8.
Bassetti, R.; Bassetti, M.; Mericske-Stern, R.; Enkling, N. Piezoelectric alveolar ridge splitting technique with simultaneous implant
placement: A cohort study with 2-year radiographic results. Int. J. Oral Maxillofac. Implant.
2013
,28, 1570–1580. [CrossRef]
[PubMed]
9.
Agabiti, I.; Botticelli, D. Two-Stage Ridge Split at Narrow Alveolar Mandibular Bone Ridges. J. Oral Maxillofac. Surg.
2017
,75,
2115.e1–2115.e12. [CrossRef] [PubMed]
10.
Cassetta, M.; Perrotti, V.; Calasso, S.; Piattelli, A.; Sinjari, B.; Iezzi, G. Bone formation in sinus augmentation procedures using
autologous bone, porcine bone, and a 50:50 mixture: A human clinical and histological evaluation at 2 months. Clin. Oral Impl.
2015,26, 1180–1184. [CrossRef] [PubMed]
11.
Cassetta, M.; Altieri, F.; Di Giorgio, R.; Barbato, E. Palatal orthodontic miniscrew insertion using a CAD-CAM surgical guide:
Description of a technique. Int. J. Oral Maxillofac. Surg. 2018,47, 1195–1198. [CrossRef] [PubMed]
12.
Cassetta, M.; Altieri, F.; Giansanti, M.; Bellardini, M.; Brandetti, G.; Piccoli, L. Is there a learning curve in static computer-assisted
surgery? A prospective clinical study. Int. J. Oral Maxillofac. Surg. 2020,49, 1335–1342. [CrossRef] [PubMed]
... Robotic technology has been integrated into surgical procedures, including dental implants. While there are challenges, a dual-robot system has been developed to increase flexibility in the implant process [46][47][48]. ...
Chapter
Full-text available
Dental implant surgery is one of the most common oral and maxillofacial surgical procedures performed today. While standard drilling protocols recommended by implant manufacturers can be used for routine cases, routine osteotomies may not be sufficient for implant stability in different bone types or in cases where the bone structure differs due to local or systemic reasons. The use of various modified osteotomy (drilling) protocols to solve such cases contributes positively to primary implant stability.
... This application also allows for a 3D (three-dimensional) view of the guide from a variety of angles and planes. The present guide's high accuracy, outstanding predictability, timeeffectiveness, and flexibility should encourage doctors to utilize this minimally invasive surgical approach; nevertheless, controlled clinical trials are needed to determine both the benefits and any potential downsides (13). Recent research has validated the accuracy of utilizing virtual planning to evaluate the drilling location, and the outcomes of using this software for guided implant surgery on actual patients have been favorable. ...
... The accuracy of the printed guides [64] and implants has been verified by many researchers [82]. While the virtual planning software allows to collect data for creating accurate implants or surgical guides [83], comparing the actual implants with planned implants allows the assessment of their accuracy [82]. The effect of build orientation and layer height on the marginal fit and the internal gap of models have been evaluated reporting that the 45 and 60 degree build orientations gave clinically acceptable models in line with milling and cast restoration, while the layer height of 100 µm and 50 µm had a similar marginal fit when printed on the D2-120 (Hephzibah, Incheon, Korea) DLP 3D printer [84]. ...
Article
Full-text available
Medical 3D printing is a complex, highly interdisciplinary, and revolutionary technology that is positively transforming the care of patients. The technology is being increasingly adopted at the Point of Care (PoC) as a consequence of the strong value offered to medical practitioners. One of the key technologies within the medical 3D printing portfolio enabling this transition is desktop inverted Vat Photopolymerization (VP) owing to its accessibility, high quality, and versatility of materials. Several reports in the peer-reviewed literature have detailed the medical impact of 3D printing technologies as a whole. This review focuses on the multitude of clinical applications of desktop inverted VP 3D printing which have grown substantially in the last decade. The principles, advantages, and challenges of this technology are reviewed from a medical standpoint. This review serves as a primer for the continually growing exciting applications of desktop-inverted VP 3D printing in healthcare.
Article
In surgical dentistry, the sampling of the biomaterial of the jaws is usually carried out with the help of dental trepans. As a result of osteotomy, a friction force inevitably arises during trepan biopsy, which can lead to local hyperthermia and, as a consequence, coagulation necrosis of both the bone tissue of the jaw itself and damage to the resulting biopsy. Local overheating can lead to complicated healing of a bone wound in the area of a trepan biopsy, lead to difficulties in verifying the morphological picture of the disease and, as a consequence, further treatment of the patient. When conducting a navigational trepan biopsy using a surgical template, the risk of hyperthermic exposure increases, and the question of choosing the rotation speed becomes obvious. The literature presents limited data on osteotomy regimes using a trepan cutter during jaw bone biopsy, including using a navigational surgical template, which determined the relevance of the study. The purpose of the study: to determine the permissible speed of rotation of the trepan cutter during the navigation trepan biopsy of the jaw bones. Materials and methods: 20 (5) micro-preparations were made from trepan biopsies of the femur of cattle, obtained at speeds of 800 rpm, 500 rpm, 250 rpm, 50 rpm in the classical way; 15 (5) micro-preparations were also made from trepan biopsies obtained at speeds of 350 rpm, 200 rpm, 50 rpm using a surgical navigation template. The width of pathological changes in the tectorial properties of ostein due to coagulation damage of the bone matrix in microns was measured using SlideViewer (3DHISTECH), a built-in tool for measuring linear parameters in microns. The statistical significance of the obtained values was determined using the Kraskel – Wallis H-test. Results: with osteotomy at a speed of 50 rpm, the width of the bone matrix damage reached up to 10 microns. As the rotation speed increased, the width of the damage also increased: at 200 rpm – Me = 36.8 microns, 350 rpm – Me = 98.6 microns. Conclusion: when conducting a navigational trepan biopsy using a surgical template, the recommended rotation speed of the instrument is up to 350 rpm.
Article
Full-text available
Panoramic radiographs and computed tomography (CT) play a paramount role in the accurate diagnosis, treatment planning, and prognostic evaluation of various complex dental pathologies. The advent of cone-beam computed tomography (CBCT) has revolutionized the practice of dentistry, and this technique is now considered the gold standard for imaging the oral and maxillofacial area due to its numerous advantages, including reductions in exposure time, radiation dose, and cost in comparison to other imaging modalities. This review highlights the broad use of CBCT in the dentomaxillofacial region, and also focuses on future software advancements that can further optimize CBCT imaging.
Article
Full-text available
Over the past decades, evolution has been seen in all specialties of dentistry, in terms of unfolding newer facts, treatment approaches and redefining existing concepts. At the back of all these developments, there has been an important role of advancing diagnostic tools, specially imaging methods. Dental imaging has covered a long journey from the simple intra-oral Periapical X-rays to advanced imaging techniques like computed tomography, cone beam computed tomography, magnetic resonance imaging and ultrasonography. Most of these developments started in the medicine, but in no time they had gained a crucial role in diagnosis & treatment planning for maxillofacial pathologies. Major paradigm shift in imaging was arrived with the conversion of analogue to digital radiography. This has not only made the process simpler and faster but also made image storage, manipulation, retrieval and transmission easier. The three- dimensional imaging of complex craniofacial structures is made even more accessible with the advent of cone beam computed tomography. Reduced scan time, radiation dose and enhanced image characteristics are the most promising features of this technology. This paper is to review current advances in imaging technology and their uses in different specialties of dentistry.
Article
Full-text available
Purpose: Extended grafting procedures in atrophic ridges are invasive and time-consuming and increase cost and patient morbidity. Therefore, ridge-splitting techniques have been suggested to enlarge alveolar crests. The aim of this cohort study was to report techniques and radiographic outcomes of implants placed simultaneously with a piezoelectric alveolar ridge-splitting technique (RST). Peri-implant bone-level changes (ΔIBL) of implants placed with (study group, SG) or without RST (control group, CG) were compared. Materials and methods: Two cohorts (seven patients in each) were matched regarding implant type, position, and number; superstructure type; age; and gender and received 17 implants each. Crestal implant bone level (IBL) was measured at surgery (T0), loading (T1), and 1 year (T2) and 2 years after loading (T3). For all implants, ΔIBL values were determined from radiographs. Differences in ΔIBL between SG and CG were analyzed statistically (Mann-Whitney U test). Bone width was assessed intraoperatively, and vertical bone mapping was performed at T0, T1, and T3. Results: After a mean observation period of 27.4 months after surgery, the implant survival rate was 100%. Mean ΔIBL was -1.68 ± 0.90 mm for SG and -1.04 ± 0.78 mm for CG (P = .022). Increased ΔIBL in SG versus CG occurred mainly until T2. Between T2 and T3, ΔIBL was limited (-0.11 ± 1.20 mm for SG and -0.05 ± 0.16 mm for CG; P = .546). Median bone width increased intraoperatively by 4.7 mm. Conclusions: Within the limitations of this study, it can be suggested that RST is a well-functioning one-stage alternative to extended grafting procedures if the ridge shows adequate height. ΔIBL values indicated that implants with RST may fulfill accepted implant success criteria. However, during healing and the first year of loading, increased IBL alterations must be anticipated.
Article
Static computer-assisted surgery (s-CAS) has been introduced to improve the results of implantology. A prospective cohort study was conducted following the STROBE guidelines to determine the presence of a learning curve in s-CAS. Six partially and six totally edentulous patients were treated by two surgeons experienced in implantology but completely inexperienced in s-CAS. Preoperative and postoperative computed tomography scans were matched to assess coronal, apical, and angular deviation and the positioning error. The accuracy data were used to evaluate the learning curve. Fifty-six implants were inserted. In partially and totally edentulous patients, the mean (range; standard deviation) coronal deviation was 0.87 (0.34–1.27; 0.35) and 1.24 (0.72–2.67; 0.79); the mean apical deviation was 1.13 (0.48–1.63; 0.39) and 1.52 (0.88–3.84; 1.15); the mean angular deviation was 2.63 (1.89–4.50; 0.98) and 3.59 (1.69–6.30; 1.65); and the mean positioning error was 0.80 (0.32–1.25; 0.35) and 1.14 (0.35–2.56; 0.77), respectively. A typical ‘learning curve’ effect was not identified for s-CAS.
Article
The aim of this report was to describe a new computer-guided technique for a controlled site preparation and palatal orthodontic miniscrew insertion using a dedicated software. A surgical guide was designed after planning the appropriate insertion sites on three-dimensional images created by the fusion of cone-beam computed tomography (CBCT) and digital dental model images. Pre- and postoperative CBCT images were compared and the angular, coronal, and apical deviations between the planned and the placed miniscrews were calculated. The mean coronal and apical deviations were 1.38 mm (range: 3.48–0.15 mm; standard deviation (SD): 0.65) and 1.73 mm (range: 5.41–0.10 mm; SD: 1.03), respectively, while the mean angular deviation was 4.60° (range: 15.23–0.54°; SD: 2.54). The present surgical guide allows a controlled and accurate palatal miniscrew placement in three dimensions.
Article
Purpose When the bone ridge is corticalized, the displacement of the buccal plate may result in an unintentional malfracture. The aim of the present study was to report the results on a two-stage atrophic alveolar ridge expansion performed with a sonic-air surgical instrument. Materials and methods In the present retrospective cohort study, the atrophic distal segments of the mandible were treated using a split-thickness flaps approach and applying an alveolar ridge expansion performed in two surgical phases. A sonic-air surgical instrument was used. In the first surgery, only basal corticotomies on the buccal plate were performed. In the second stage, sagittal and vertical osteotomies were added, aiming to facilitate the displacement of the buccal bone plate. Subsequently, implants were installed into the created space between the buccal and the lingual plates. No bone substitutes were used. The width of the displaced buccal bone wall and the gaps that occurred mesially and distally to the implant were measured at the time of implant installation. Cone beam computed tomography scans (CBCTs) were taken before the first and after the second surgeries, and the width of the alveolar crest at both observations and the width of the residual mesial and distal gaps after implant installation were measured. Results Ten patients (6 females and 4 males; age 37 to 69 years) were included in the study and 15 implants were installed in expanded narrow ridges. Clinically, the mean width of the buccal bone wall was 1.2 ± 0.2 mm and the gaps ranged between 2.8 and 3.2 mm. At the radiographic assessments, the mean initial width of the alveolar bone crest was measured as 4.1 ± 0.5 mm, reaching 6.8 ± 0.9 mm after ridge expansion (P< 0.01). Conclusions The use of a modified edentulous ridge expansion (ERE) in two stages allowed the installation of implants in narrow and corticalized alveolar ridges. We suggest that the present technique is especially applicable in the distal segments of the mandible because of the low invasiveness, low risk of buccal plate fractures, reduced morbidity, and reduced costs.
Article
The brass wire ligature is an efficient method to correct a moderately mesially impacted mandibular second molar (MM2). The aim of this prospective clinical pilot study was to evaluate the influence of mandibular third molar (MM3) germectomy on the treatment time for this procedure and to determine its impact on oral health-related quality of life (OHRQoL) using the short-form Oral Health Impact Profile (OHIP-14). The STROBE guidelines were followed. Impacted MM2 were assigned randomly to receive brass wire ligature treatment either with germectomy (group A) or without germectomy (group B). Descriptive statistics and the Student t-test were used in the statistical analysis; significance was set at P � 0.05. One thousand and thirty patients were assessed. Fourteen subjects with 20 mesially angulated (range 25–40�) impacted MM2 were identified. Paired comparisons of groups A and B showed no statistically significant difference in treatment time (171 days for group A and 174 days for group B; P = 0.440), but a statistically significant difference in OHIP-14 values at the 3- (P = 0.017) and 7-day (P = 0.002) follow-up. The brass wire technique can be used effectively in moderately impacted MM2, but the combined use of MM3 germectomy does not influence the treatment time and shows a negative impact on OHRQoL.
Article
Objectives: The aim of this study was to perform a 2 months clinical and histological comparison of autologous bone, porcine bone, and a 50 : 50 mixture in maxillary sinus augmentation procedures. Materials and methods: A total of 10 consecutive patients, undergoing two-stage sinus augmentation procedures using 100% autologous bone (Group A), 100% porcine bone (Group B), and a 50 : 50 mixture of autologous and porcine bone (Group C) were included in this study. After a 2-month healing period, at the time of implant insertion, clinical evaluation was performed and bone core biopsies were harvested and processed for histological analysis. Results: The postoperative healing was uneventful regardless of the materials used for the sinus augmentation procedures. The histomorphometrical analysis revealed comparable percentages of newly formed bone, marrow spaces, and residual grafted material in the three groups. Conclusion: The clinical and histological results of this study indicated that porcine bone alone or in combination with autologous bone are biocompatible and osteoconductive materials and can be successfully used in sinus augmentation procedures.
Article
Background: Research interest on immediate placement of dental implants has shifted from implant survival toward optimal preservation of soft and hard tissues. The aim of this study is to systematically assess the condition of implant survival, peri-implant hard and soft tissue changes, esthetic outcome, and patient satisfaction of immediately placed single-tooth implants in the esthetic zone. Methods: MEDLINE, EMBASE, and CENTRAL databases were searched for publications up to June 2013. Studies reporting on implant survival, changes in hard and soft peri-implant tissues, esthetic outcome, and patient satisfaction were considered. A pooled analysis was performed to identify factors associated with survival and peri-implant tissue changes after immediate implant placement. Results: Thirty-four studies were considered eligible. Immediate placement of single-tooth implants in the esthetic zone was accompanied by excellent 1-year implant survival (97.1%, 95% confidence interval [CI]: 0.958 to 0.980). Mean marginal peri-implant bone loss was 0.81 ± 0.48 mm, mean loss of interproximal peri-implant mucosa level was 0.38 ± 0.23 mm, and mean loss of peri-implant midfacial mucosa level was 0.54 ± 0.39 mm. Regression analysis revealed that delayed provisionalization (odds ratio [OR] 58.03, 95% CI: 8.05 to 418.41, P <0.000), use of a flap (OR 19.87, 95% CI: 10.21 to 38.66, P <0.000), and use of a connective tissue graft (OR 4.56, 95% CI: 1.72 to 12.08, P <0.002) were associated with marginal peri-implant bone-level change >0.50 mm. Because of underreporting, esthetic results and patient outcome did not allow for reliable analysis. Conclusion: Immediate placement with immediate provisionalization of dental implants in the esthetic zone results in excellent short-term treatment outcome in terms of implant survival and minimal change of peri-implant soft and hard tissue dimensions.
Article
The aim of this study was to measure implant stability quotient (ISQ) values in grafted sites during 5 years of follow-up. Sixteen patients received a total of 36 implants inserted in sites treated with autologous bone (group A) or porcine bone in addition to autologous bone (group B). In both groups, resonance frequency analysis (RFA) values increased during the observation period. At 2 months, statistical analysis showed significantly lower ISQ values for group B than for group A (P = .0134) and significantly higher ISQ values in the mandible than in the maxilla (P = .0251). RFA measurements suggested stable long-term results for implants inserted in both groups.