[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate the reliability of measurements obtained after the superimposition of three-dimensional (3D) digital models by comparing them with those obtained from lateral cephalometric radiographs and photocopies of plaster models for the evaluation of upper molar distalization.
Data were collected from plaster models and lateral cephalometric radiographs of 20 Class II patients whose maxillary first molars were distalized with an intraoral distalizer. The posterior movements of the maxillary first molars were evaluated using lateral cephalometric radiographs (group CP), photocopies of plaster models (group PH), and digitized 3D models (group TD). Additionally, distalization and expansion of the other teeth and the degrees of molar rotation were measured in group PH and group TD and compared between the two groups.
No significant difference was observed regarding the amount of molar distalization among the three groups. A comparison of the aforementioned parameters between group PH and group TD did not reveal any significant difference.
3D digital models are reliable to assess the results of upper molar distalization and can be considered a valid alternative to conventional measurement methods.
Full-text · Article · Mar 2015 · Korean Journal of Orthodontics
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate the preventive and/or reparative effects of low-level laser therapy (LLLT) on orthodontically induced inflammatory root resorption (OIIRR) in rats. Thirty rats were divided into four groups (short-term control (SC), short-term laser (SL), long-term control (LC), long-term laser (LL)). In all groups, the left first molar was moved mesially for 11 days. At the end of this period, the rats in groups SC and SL were killed in order to observe the resorption lacunas and to evaluate whether LLLT had any positive effect on root resorption. The groups LC and LL were remained for a healing period of 14 days in order to observe spontaneous repair of the resorption areas and investigate whether LLLT had reparative effects on root resorption. A Ga-Al-As diode laser (Doris, CTL-1106MX, Warsaw, Poland) with a wavelength of 820 nm was used. In SL group, the first molars were irradiated with the dose of 4.8 J/cm2 (50 mW, 12 s, 0.6 J) on every other day during force application. In LL group, the irradiation period was started on the day of appliance removal and the first molars were irradiated with the dose of 4.8 J/cm2 on every other day for the next 14 days. LLLT significantly increased the number of osteoblasts and fibroblasts, and inflammatory response in SL group in comparison with SC group (P =.001). The amount of resorption did not represent any difference between the two groups (P =.16). In LL group, LLLT significantly increased the number of fibroblasts and decreased the amount of resorption in comparison with LC group (P =.001; P =.02). Both parameters indicating the reparative and the resorptive processes were found to be increased by LLLT applied during orthodontic force load. LLLT applied after termination of the orthodontic force significantly alleyed resorption and enhanced/accelerated the healing of OIIRR. LLLT has significant reparative effects on OIIRR while it is not possible to say that it definitely has a preventive effect.
No preview · Article · Jan 2015 · Lasers in Medical Science
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to investigate the effect that dosage has on the efficiency of low-level laser therapy (LLLT) in bone formation in a rat study model. Twenty-eight rats were divided into four groups as only expansion (OE), expansion + low dose (0.15 J) (LD), expansion + medium dose (0.65 J) (MD), and expansion + high dose (198 J) (HD) laser therapy groups. The midpalatal suture was expanded during 5 days. Afterwards, irradiations were started and performed with an 820 nm, continuous wave, Ga-Al-As diode laser (Doris, CTL-1106MX, Warsaw, Poland). At the end of experiment, the premaxillae of the animals were dissected. The sections were transferred into PC environment and analyzed by using Image Analysis program. Number of osteoblasts, osteoclasts, fibroblasts, vessels, transforming growth factor beta (TGF-β) expression, and new bone formation were evaluated with this program. Amount of expansion did not show any difference among the groups. All parameters except the number of osteoclasts were increased in all lased groups while that parameter was significantly decreased. Vessels, TGF-β expression, and new bone formation were mostly increased in LD group followed by HD group. Among the lased groups, a significant difference was observed only for the amount of new bone formation, which was between the LD and the MD groups. On the other hand, the difference in this parameter was insignificant between OE and MD groups. Low-level laser therapy with both 5 and 6,300 J/cm(2) doses was found to be significantly effective, while the 20 J/cm(2) dose did not show a significant effect in increasing new bone formation. This finding reveals that the efficiency of the therapy is affected by the dosage.
No preview · Article · Sep 2014 · Lasers in Medical Science
[Show abstract][Hide abstract] ABSTRACT: Objective:
To examine the effect of maxillary incisor proclination due to orthodontic treatment upon the sagittal position of point A and evaluate the effect of this possible movement of point A on sella-nasion-point A (SNA) angle.
Materials and methods:
A study group was formed from 25 subjects (12 male and 13 female) who had Class II division 2 malocclusion with retroclined upper incisors, and a control group was formed from 25 subjects (12 male and 13 female) who had minor crowding in the beginning of the treatment and required no or minimal maxillary anterior tooth movement. Treatment changes in maxillary incisor inclination, sagittal position of point A, SNA angle, and movement of incisor root apex and incisal edge were calculated on pretreatment and posttreatment lateral cephalographs.
Maxillary incisors were significantly proclined (17.33°) in the study group and not significantly proclined (1.81°) in the control group. This proclination resulted in 2.12-mm backward movement of the root apex and 5.76-mm forward movement of the incisal edge of maxillary incisors. Point A moved 1.04 mm backward (P = .582) and 0.48 mm (P = .811) forward in the study and control groups, respectively. Incisor root apex and incisal edge almost remained stable in the control group. No significant change was observed in the value of the SNA angle in both the study and control groups.
Proclination of maxillary incisors accompanied by backward movement of incisor root apex caused posterior movement of point A. However, this posterior movement does not significantly affect the SNA angle.
No preview · Article · May 2013 · The Angle Orthodontist
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to investigate the effect of low-level laser therapy (LLLT) on reducing post-adjustment orthodontic pain via evaluation of gingival crevicular fluid (GCF) composition changes at the level of prostaglandin-E(2) (PGE(2)) and visual analogue scale (VAS).
LLLT has been found to be effective in pain relief. PGE(2) has the greatest impact on the process of pain signals and can be detected in GCF in order to investigate the response of dental and periodontal tissues in a biochemical manner.
Nineteen patients (11 females and 8 males; mean age 13.9 years) were included in this study. Maxillary first molars were banded and then a randomly selected first molar at one side was irradiated (λ820 nm; continuous wave; output power: 50 mW; focal spot: 0.0314 cm(2); exposure duration: 5 sec; power density: 1.59 W/cm(2); energy dose: 0.25 J; energy density: 7.96 J/cm(2) for each shot), while the molar at the other side was served as placebo control. The GCF was collected from the gingival crevice of each molar to evaluate PGE(2) levels, before band placement, 1 and 24 h after laser irradiation. Pain intensity was analyzed at 5 min, 1 h, and 24 h after band placement by using VAS.
Although no difference was found in pain perception at 5 min and 1 h, significant reduction was observed with laser treatment 24 h after application (p<0.05). The mean PGE(2) levels were significantly elevated in control group, whereas a gradual decrease occurred in laser group. The difference in PGE(2) levels at both 1 and 24 h were statistically significant between two groups (p<0.05).
The significant reductions in both pain intensity and PGE(2) levels revealed that LLLT was efficient in reducing orthodontic post-adjustment pain.
Full-text · Article · Jul 2012 · Photomedicine and laser surgery
[Show abstract][Hide abstract] ABSTRACT: In this report, we present the case of a girl with delayed odontogenesis of a lower second premolar for which she was followed up for 8.5 years. Congenital absence of permanent mandibular second premolars was observed at the initial radiographic examination at 8 years and 1 month. One year later, during the treatment period, an unexpected odontogenesis of a right second premolar was diagnosed on follow-up radiography. The original treatment plan was revised and a new plan was successfully implemented. Th is unusual case showed that the orthodontist's clinical philosophy must be flexible because unexpected situations can arise, especially when treating growing patients.
Preview · Article · Apr 2012 · Korean Journal of Orthodontics
[Show abstract][Hide abstract] ABSTRACT: To determine the pulpal blood flow (PBF) changes in anchorage teeth associated with the high forces of a rapid maxillary expansion (RME) appliance.
The study was performed with 14 girls and 7 boys for a total of 21 patients between 10 and 15 years of age (mean, 13.1 +/- 1.39 years). A modified acrylic bonded RME appliance was used as an expansion appliance. Laser Doppler flowmetry was used for the pulpal perfusion measurements. Records were taken from 42 upper central incisors, 28 canines, and 42 first molars at the following time intervals: just before expansion (T1); at the first week of expansion (T2); at the end of the expansion process (T3); and at the third (T4), seventh (T5), and 12th weeks of retention (T6). The data gained were statistically evaluated by parametric tests.
PBF values of the anchorage teeth were doubled at the first week of expansion; however, these values began to decrease because of separation of the median palatal suture. PBF values tended to reach their initial values during the retention period. Pulpal perfusion changes of all examined anchorage teeth were similar to each other from the beginning to the end of the evaluation.
PBF changes that occur with RME are reversible.
Preview · Article · Nov 2010 · The Angle Orthodontist
[Show abstract][Hide abstract] ABSTRACT: Objective: Intraoral noncompliance upper molar distalization techniques have gained in popularity and have subsequently found to be successful in Class II correction. The aim of the present study was to introduce a screw supported intraoral distalization appliance and investigate its efficiency. Methods: Twenty-one subjects (11 females, 10 males; average age of 14.9 years) with Angle Class II malocclusion participated in this study. Two screws were inserted behind the incisive foramen and immediately loaded to distalize the upper first molars. An intraoral screw supported distalization appliance was used to distalize the upper molars in order to achieve a Class I molar relationship. Skeletal and dental changes were evaluated using cephalometric and three-dimensional (3D) model analysis. Results: Upper molars were distalized 3.95 mm on average and a Class I molar relationship was achieved without any anchorage loss. The upper molars were tipped only 1.49° and the upper right and left molars were rotated only 0.54° and 0.74° respectively which were statistically non-significant (p > 0.05). Conclusions: The newly designed screw supported noncompliance distalization appliance was found to be an effective device for achieving bodily molar distalization without any anchorage loss.
Full-text · Article · Aug 2010 · The Korean Journal of Orthodontics
[Show abstract][Hide abstract] ABSTRACT: The aim of this prospective in-vivo study was to investigate the possible effects of temperature changes from various adhesive cleanup procedures on pulpal tissue.
The materials, consisting of 40 sound maxillary and mandibular premolars to be extracted during orthodontic treatment, were randomly assigned to 4 groups, with 1 group as the control. The teeth in the 3 study groups were etched; brackets were bonded and then debonded. The remaining adhesive was removed with a tungsten carbide bur by using a high-speed hand piece. The teeth in the control group were not etched and bonded. In group 1, the residual adhesive was removed with water cooling, and the teeth were extracted 24 hours later. In group 2, the residual adhesive was removed without water cooling, and the teeth were extracted 24 hours later. In group 3, the residual adhesive was removed without water cooling, and the teeth were extracted 20 days later. The teeth were prepared for histologic examination, and the number of vessels, vessel areas and perimeters, extravasation of red blood cells, vascular congestion, and inflammatory cell infiltration were evaluated to determine pulpal tissue changes.
According to the findings from histologic and immunohistochemical evaluations, the coronal pulps of the teeth in groups 1 and 3 were almost similar to the control teeth, but some distinct pathologic changes were observed in group 2.
Adhesive removal without water cooling caused some vascular and pulpal tissue alterations, but these were tolerated by the pulpal tissues, so the changes were reversible.
Full-text · Article · Jul 2010 · American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics
[Show abstract][Hide abstract] ABSTRACT: INTRODUCTION: The aim of this prospective in-vivo study was to investigate the possible effects of temperature changes from various adhesive cleanup procedures on pulpal tissue. METHODS: The materials, consisting of 40 sound maxillary and mandibular premolars to be extracted during orthodontic treatment, were randomly assigned to 4 groups, with 1 group as the control. The teeth in the 3 study groups were etched; brackets were bonded and then debonded. The remaining adhesive was removed with a tungsten carbide bur by using a high-speed hand piece. The teeth in the control group were not etched and bonded. In group 1, the residual adhesive was removed with water cooling, and the teeth were extracted 24 hours later. In group 2, the residual adhesive was removed without water cooling, and the teeth were extracted 24 hours later. In group 3, the residual adhesive was removed without water cooling, and the teeth were extracted 20 days later. The teeth were prepared for histologic examination, and the number of vessels, vessel areas and perimeters, extravasation of red blood cells, vascular congestion, and inflammatory cell infiltration were evaluated to determine pulpal tissue changes. RESULTS: According to the findings from histologic and immunohistochemical evaluations, the coronal pulps of the teeth in groups 1 and 3 were almost similar to the control teeth, but some distinct pathologic changes were observed in group 2. CONCLUSIONS: Adhesive removal without water cooling caused some vascular and pulpal tissue alterations, but these were tolerated by the pulpal tissues, so the changes were reversible.
No preview · Article · Jul 2010 · American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics
[Show abstract][Hide abstract] ABSTRACT: To compare the effects of rapid maxillary expansion (RME) and surgically assisted rapid maxillary expansion (SARME) on dentoalveolar structures following orthodontic treatment, as well as stability at 2-year follow-up.
Two groups of subjects were used in the study. Group 1 consisted of 14 subjects (mean age, 12.7 +/- 1.4 years) who were treated with RME, and Group 2 consisted of 13 subjects (mean age, 18.5 +/- 2.3 years) who were treated with SARME. In both groups, all cases had a maxillary width deficiency with bilateral crossbites. Maxillary dental casts were available at three different intervals: pretreatment (T1), after orthodontic treatment (T2), and at follow-up recall (T3). Intermolar and interpremolar width, palatal height, and maxillary arch depth and length were assessed from maxillary dental casts.
Treatment by RME and SARME produced significant increases in intermolar and interpremolar width and maxillary arch length after expansion (T2) (P < .05). The amount of relapse was not significantly different 2 years after treatment (P > .05).
Although age ranges of the patient groups are different, the dentoalveolar responses of RME and SARME were similar after orthodontic treatment.
No preview · Article · Mar 2009 · The Angle Orthodontist
[Show abstract][Hide abstract] ABSTRACT: Maxillary canine premolar transposition is the most frequently reported transposition type, which many orthodontists face. Although correcting the transposed tooth order is not advised after the eruption of the permanent tooth, several articles published in the last decade demonstrated nonextraction treatment of transposition using fixed mechanics. This article describes the nonextraction treatment of a complete transposition between a maxillary left canine and a first premolar, using similar mechanics as suggested earlier. The correct tooth order was established with a functional Class I canine and molar relationship at the end of treatment. Although triangular cortical bone resorption at the vestibule of the canine root was detected on computed tomography at the end of treatment, spontaneous regeneration of bone tissue at the resorption area was present on the postretention computed tomography scan.
Preview · Article · Oct 2008 · The Angle Orthodontist
[Show abstract][Hide abstract] ABSTRACT: To test the hypothesis that there is no difference in the movement of the upper third molars between rapid maxillary expansion (RME) and non-RME patients.
This study was performed on 30 patients divided into two groups. The study group included 20 patients who had maxillary narrowness and bilateral maxillary third molars and who had undergone RME application. The control group of 10 patients had a bilateral crossbite, had bilateral maxillary third molars, and did not receive orthodontic treatment. The records included lateral and frontal cephalometric films and maxillary plaster models. In the study group, records were taken before expansion (T1), after expansion (T2), and at the retention period (T3). T2 records were not taken in the control group because this period was too short to observe any changes. Friedman tests were used to observe within groups, and the Mann-Whitney U-test was used to see the differences between groups on films and casts.
Frontal films showed that vertical eruption occurred after the retention period in the RME cases. Cephalometric films revealed that the angular eruption occurred immediately after expansion. However, the results were not significant with respect to the control group.
The hypothesis was rejected. Rapid maxillary expansion affects maxillary third molar movement during and after the RME procedure. RME may indicate upper third molar eruption, but the final position of third molar was not different compared to the normal growth pattern.
No preview · Article · Apr 2008 · The Angle Orthodontist
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to compare nasal volume changes using acoustic rhinometry (AR) and computed tomography (CT). The subjects were 10 children (6 girls and 4 boys, with an age range of 12-14 years) who required rapid maxillary expansion (RME) on the basis of their individual malocclusion. All patients were found to have normal nasal cavities following anterior rhinoscopic examination. AR and CT were undertaken at the start of treatment (t(1)) and 6 months after expansion (t(2)). Volume changes due to expansion were evaluated using Wilcoxon's test, and the correlation between the two methods was assessed with correlation analyses. Both methods demonstrated that nasal volume significantly increased following the use of RME (P<0.05). Correlation analyses showed no difference in volume (P>0.05) using either of the two methods.
No preview · Article · Jun 2007 · The European Journal of Orthodontics
[Show abstract][Hide abstract] ABSTRACT: To test the hypothesis that there is a relationship between forward mandibular third molar migration and root curvature of the mandibular third molars.
The study is comprised of 64 patients who had a history of unilateral mandibular first molar extraction before 16 years of age with no other missing teeth or prosthetic restorations in the mandible. The extraction space was fully or partly closed. The mean remaining space was 1.1 +/- 0.41 mm. The root angles for the mesial and distal roots of the mandibular third molars were measured on the panoramic radiographs by calculating the differences between the angle formed by the long axis drawn perpendicular to the occlusal plane of the crown of mandibular third molar and the central line of the lower one ninth of the root through the root apex. The differences between the extracted and nonextracted sides for mesial and distal roots were analyzed using a paired sample t-test.
Both mesial and distal roots were approximately 8 degrees more vertical on the extraction sides than on the nonextraction sides. The differences were statistically significant.
Mesial tooth migration of mandibular third molars reduces the amount of root curvature developing on this tooth.
No preview · Article · Feb 2007 · The Angle Orthodontist
[Show abstract][Hide abstract] ABSTRACT: Early diagnosis of a transposition can simplify the orthodontic correction. In this report, we describe the orthodontic management of a patient with mandibular right lateral incisor and canine transposition. Nonextraction therapy was performed with removable multibracket appliances. Natural tooth order was attained, and a symmetric and functional Class I occlusion was achieved.
Preview · Article · Feb 2006 · American Journal of Orthodontics and Dentofacial Orthopedics
[Show abstract][Hide abstract] ABSTRACT: Third molars often become impacted because of lack of space for their eruption. Because the third molars play an important role occlusally, premolars or second molars are sometimes extracted to create space. First molars are seldom extracted to create space, but they are occasionally extracted for other reasons, especially caries. The aim of this study was to investigate the spontaneous angular and positional changes in mandibular third molars when mandibular first molars are extracted.
The sample consisted of panoramic radiographs of 107 patients (age, 18-40 years; mean, 25.69 years) who had unilateral mandibular first-molar extractions (because of caries) before age 16. Ramus relationship, impaction depth, and angulation of third molars on the extraction and nonextraction sides were assessed. A chi-square test was performed to compare the differences.
The prevalence of third molars at the anterior border of the mandibular ramus was significantly greater on the extraction side than on the nonextraction side (P < .001). Third molars were positioned more occlusally in the mandible on the nonextraction side than on the extraction side (P < .001). The prevalence of vertically angulated third molars was greater on the extraction side than on the nonextraction side (P < .001).
Mandibular first-molar extraction increases the space for mandibular third-molar eruption and helps the third molars move into better positions. But early extraction can lead to uncontrolled tipping of adjacent teeth into the extraction space. Only third-molar angle and position were evaluated in this study; problems such as dental asymmetry, premature contacts, and uncontrolled tipping should be assessed in the future.
Preview · Article · Feb 2006 · American Journal of Orthodontics and Dentofacial Orthopedics