Zafer Sari

Relationships Between Dental and Skeletal Maturity in Turkish Subjects

The aim of this study was to investigate the relationships between the stages of calcification of various teeth and skeletal maturity stages among Turkish subjects. The samples were derived from dental panoramic and hand-wrist radiographs of 500 subjects (215 males and 285 females). Calcification of the mandibular canines, first and second premolars, and second and third molars was rated according to the system of Demirjian. To evaluate the stage of skeletal maturation of each hand-wrist radiograph, nine ossification events were determined according to the systems of Björk, and Grave and Brown. Statistically significant relationships were determined between dental calcification and skeletal maturity stages according to Spearman rank-order correlation coefficients. Correlations between dental development and skeletal maturity ranged from .490 to 0.826 for females and .414 to .706 for males (P < .01). The second molar showed the highest correlation and the third molar showed the lowest correlation for female and male subjects. For both sexes, root formation of the canine as well as the first premolar was completed in the majority of the subjects at the MP3cap, PP1cap, Rcap stages. Because of the high correlation coefficients, this study suggests that tooth calcification stages from panoramic radiographs might be clinically useful as a maturity indicator of the pubertal growth period. It is appropriate to put these skeletal and dental maturation relationships into daily orthodontic diagnostic practice, when treating a Turkish patient.

Can previously bleached teeth be bonded safely

The purpose of our study was to determine the effect of a 35% hydrogen peroxide bleaching agent on the shear bond strength of metallic orthodontic brackets. Sixty premolars were randomly divided into 3 groups of 20 each. Teeth in group A were etched with 37% phosphoric acid before bonding metallic premolar brackets. Teeth in the other 2 groups were bleached with a 35% hydrogen peroxide in-office bleaching agent according to the manufacturers recommendations. Twenty bleached teeth (group B) were bonded immediately, and the other 20 (group C) were stored in artificial saliva for 30 days before bonding. Shear bond strength of these brackets was measured on a universal testing machine and recorded in MPa. Adhesive remnant index (ARI) scores were determined after the brackets failed. Data were analyzed with analysis of variance (ANOVA) and chi-square tests. The shear bond strength values of groups A, B, and C were 12.9 +/- 3.4, 12.0 +/- 4.6, and 14.8 +/- 4.0 MPa, respectively. Results of ANOVA showed no statistically significant differences in shear bond strengths between groups (P >.05). ARI scores were significantly different in all groups. The unbleached groups failures were primarily at the bracket/adhesive interface, whereas the bleached groups either showed cohesive failures within the adhesive or failed at the adhesive/enamel interface. The results of this study suggest that office bleaching with hydrogen peroxide does not adversely affect the bond strengths of brackets bonded immediately after bleaching or 30 days after bleaching, even though bleaching can result in differences in the failure site.

Intermaxillary Tooth Size Discrepancy and Malocclusion: Is There a Relation?

The aims of this study were to identify the possible sex differences in tooth size ratios between males and females, to determine whether there is a difference in the incidence of tooth size discrepancies for both the anterior and overall ratios when comparing with Angle Class I; Class II, division 1; Class II, division 2; and Class III malocclusion groups, to compare the tooth size ratios of different malocclusion groups with the anterior and overall tooth size ratios of 150 untreated normal occlusion subjects. In addition, the aim was to determine the percentage of tooth size discrepancies outside 2 SD from Bolton means for tooth ratios present in each malocclusion group and in the overall sample of this study. This study consisted of 150 subjects who served as the normal occlusion group and 560 patients who showed four different malocclusion characteristics (Angle Class I; Class II, division 1; Class II, division 2; and Class III). Tooth size measurements were performed on the models of normal occlusion and pretreatment models. For statistical evaluation, Students t-test, analysis of variance and Tukey Honestly Significant Difference tests were performed. A significant sex difference was found only in the overall ratio for normal occlusion subjects (P < .001). All malocclusion groups showed statistically significant higher overall ratios than the normal occlusion group (P < .001). There were no statistically significant differences among malocclusion groups; however, there were a large number of patients within each group who had discrepancies greater than 2 SD from the mean. Further investigations are needed to explain the probable racial differences and relationships between malocclusion and tooth size measurements.

Dental and alveolar arch widths in normal occlusion, class II division 1 and class II division 2.

The aim of this study was to compare the transverse dimensions of the dental arches and alveolar arches in the canine, premolar, and molar regions of Class II division 1 and Class II division 2 malocclusion groups with normal occlusion subjects. This study was performed using measurements on dental casts of 150 normal occlusion (mean age: 21.6 +/- 2.6 years), 106 Class II division 1 (mean age: 17.2 +/- 2.4 years), and 108 Class II division 2 (mean age: 18.5 +/- 2.9 years) malocclusion subjects. Independent-samples t-test was applied for comparisons of the groups. These findings indicate that the maxillary interpremolar width, maxillary canine, premolar and molar alveolar widths, and mandibular premolar and molar alveolar widths were significantly narrower in subjects with Class II division 1 malocclusion than in the normal occlusion sample. The maxillary interpremolar width, canine and premolar alveolar widths, and all mandibular alveolar widths were significantly narrower in the Class II division 2 group than in the normal occlusion sample. The mandibular intercanine and interpremolar widths were narrower and the maxillary intermolar width measurement was larger in the Class II division 2 subjects when compared with the Class II division 1 subjects. Maxillary molar teeth in subjects with Class II division 1 malocclusions tend to incline to the buccal to compensate the insufficient alveolar base. For that reason, rapid maxillary expansion rather than slow expansion may be considered before or during the treatment of Class II division 1 patients.

Rapid maxillary expansion. Is it better in the mixed or in the permanent dentition

The aim of this study was to compare the dentoskeletal effects of a modified acrylic-bonded rapid maxillary expansion (RME) device when it is used in the mixed and permanent dentitions. The study group consisted of 51 patients in the mixed and permanent dentition (26 girls and 25 boys) who underwent RME treatment. Group 1 was composed of 34 subjects in the mixed dentition (19 girls and 15 boys; mean age, 9.2 +/- 1.3 years). Group 2 consisted of 17 subjects in the permanent dentition (seven girls and 10 boys; mean age 12.7 +/- 1.2 years). Lateral and frontal cephalograms and upper dental casts were collected before treatment (T1), after treatment (T2), and after retention (T3). Intragroup and intergroup changes were evaluated by paired t-test and Students t-test, respectively. In both groups after RME, the maxilla moved forward; mandible rotated posteriorly; facial height increased; nasal, maxillary, and maxillary intercanine and first molar widths increased; and the upper molars tipped buccally. Almost all these significant changes were stable at follow-up (T3). When overall (T1 - T3) differences were considered, upper molars tipped more, and the ANB angle increased less in the mixed dentition group compared with the permanent dentition group (P < .01). Within the limits of this study, the results suggest that the orthopedic effects of RME are not as great as expected at early ages, and it might be a better alternative to delay RME to early permanent dentition.

The Effects of Early Preorthodontic Trainer Treatment on Class II, Division 1 Patients

The aim of this study was to clarify the dentoskeletal treatment effects induced by a preorthodontic trainer appliance treatment on Class II, division 1 cases. Twenty patients (10 girls and 10 boys, mean age 9.6 +/- 1.3 years) with a Class II, division 1 malocclusion were treated with preorthodontic trainer appliances (Myofunctional Research Co., Queensland, Australia). The patients were instructed to use the trainer every day for one hour and overnight while they slept. A control group of 20 patients (mean age 10.2 +/- 0.8 years) with untreated Class II, division 1 malocclusions was used to eliminate possible growth effects. Lateral cephalograms were taken at the start and end of treatment. Final cephalograms were taken 13.1 +/- 1.8 months after trainer application, compared with a mean of 11.2 +/- 2.4 months later for the control group. The mean and standard deviations for cephalometric measurements were analyzed by paired-samples t-test and independent-samples t-tests. At the end of the study period, the trainer group subjects showed significant changes including anterior rotation and sagittal growth of the mandible, increased SNB and facial height, reduced ANB, increased lower incisor proclination, retroclination of upper incisors, and overjet reduction. However, only total facial height increase, lower incisor proclination, and overjet reduction were significantly higher when compared with the changes observed in the control group. This study demonstrates that the preorthodontic trainer application induces basically dentoalveolar changes that result in significant reduction of overjet and can be used with appropriate patient selection.

Are the Flowable Composites Suitable for Orthodontic Bracket Bonding

The study aims to determine the shear bond strength (SBS) values of different flowable composites (Pulpdent Flows-Rite, 3M Filtek Flow, and Heraeus Kulzer Flow Line) in comparison with a conventional orthodontic adhesive and the bond failure sites of these composites. Eighty extracted human premolars were divided into four groups of 20 teeth each. Brackets were bonded to the teeth in each test group with different composites, according to the manufacturers instructions. SBS values of these brackets were recorded (in MPa) using a universal testing machine. Adhesive remnant index (ARI) scores were determined after the failure of brackets. Data were analyzed using analysis of variance (ANOVA), Tukey honestly significant difference, and chi-square tests. SBS values of groups 1 (Transbond XT), 2 (Flows-Rite), 3 (Flow), and 4 (Flow Line) were found to be 17.10 +/- 2.48 MPa, 6.60 +/- 3.2 MPa, 7.75 +/- 2.9 MPa, and 8.53 +/- 3.50 MPa, respectively. The results of this study demonstrate that the orthodontic adhesive (Transbond XT) had higher SBS values than the flowable composites. Results of ANOVA revealed statistically significant differences among the groups (P < .05). The SBS values were significantly lower in all flowable composite groups than the orthodontic adhesive. ARI scores were significantly different between the orthodontic adhesive and all the flowable groups investigated. The use of flowable composites is not advocated for orthodontic bracket bonding because of significantly lower SBS values achieved.

Dental and Alveolar Arch Widths in Normal Occlusion and Class III Malocclusion

The aim of this study was to compare the transverse dimensions of the dental arches and alveolar widths of Class III malocclusion group with a group of untreated normal occlusion subjects. This study was performed using measurements on dental casts of 150 normal occlusion (mean age, 21.6 +/- 2.6 years) and 100 Class III malocclusion (mean age, 15.4 +/- 2.2 years) subjects. Independent samples t-test was applied for comparing the groups. The findings of this study indicated that the mandibular intercanine and intermolar alveolar widths were significantly larger in the Class Ill group when compared with the normal occlusion sample (P < .001). Maxillary interpremolar, intermolar widths and all maxillary alveolar width measurements were significantly narrower in the Class III group (P < .001). In addition, the lower canine and premolar alveolar width measurements were also statistically significantly larger in the normal occlusion group when compared with the Class III malocclusion group (P < .001). Subjects with Class III malocclusion tend to have the maxillary teeth inclined to the lingual and mandibular teeth inclined to the buccal direction because of the restriction of maxillary growth and development according to dental arch width measurements. Therefore, rapid maxillary expansion should be considered before or during the treatment of a Class III patient with or without face-mask therapy.

Maxillary expansion in the mixed dentition: rapid or semi-rapid?

The purpose of this study was to investigate the effects of rapid maxillary expansion (RME) and semi-rapid maxillary expansion (SRME) in the mixed dentition period. The SRME group consisted of 18 patients (11 girls and 7 boys) with a mean age of 8.63 +/- 1.09 years and the RME group 17 patients (11 girls and 6 boys) with a mean age of 8.78 +/- 1.21 years. A splint type tooth- and tissue-borne modified bonded RME appliance was used, with the patients activating the screw two-quarter turns per day for the first week, followed by one-quarter turn every other day in the SRME group and two-quarter turns per day throughout treatment in the RME group. The average treatment time was 57.16 +/- 21.52 and 21.23 +/- 8.36 days for the SRME and RME groups, respectively. A Wilcoxon signed rank test was used to evaluate the treatment effects [pre-(T(0)) - post-(T(1)) treatment changes] for both the SRME and RME groups and a Mann-Whitney U-test to determine the differences between the two groups (T(0)-T(1) changes SRME versus T(0)-T(1) changes RME). For both groups, the maxillary base, nasal cavity width and upper intercanine and intermolar distances were increased, and the upper molars tipped buccally. The only statistically significant (P < 0.05) difference between two groups was in inferior movement of posterior nasal spine (PNS) relative to the SN plane (SN upper left and right quadrantsPNS). This measurement increased in both groups yet significantly more in the RME group. The results suggest that RME and SRME have similar effects on dentofacial structures both in the transverse, vertical, and sagittal planes.

Occlusal Contact Changes with Removable and Bonded Retainers in a 1-Year Retention Period

OBJECTIVE To test the hypothesis that there is no difference in the number of occlusal contacts in centric occlusion in patients treated with bonded and removable retention procedures and a control group during a 1-year retention period. MATERIALS AND METHODS Twenty-five patients received a removable Hawley retainer, and 25 patients received maxillary and mandibular bonded retainers. The retainer patients were compared with 20 control subjects with normal occlusions. Silicone-based impression bites were used to record occlusal contacts. Paired-sample t-test, analysis of variance (ANOVA), and Tukey tests were used to evaluate intragroup and intergroup differences. RESULTS An increased number of occlusal contacts were recorded in total-arch and posterior combined (actual/near) teeth during the retention period as compared with the control group. In the Hawley group, actual and total contacts on the first and second molar and actual contacts on the premolar and canine showed statistically significant increases. In the bonded retainer group, near and total contacts on the first and second molars and premolars showed statistically significant increases. Slight occlusal changes were seen in the control sample during the observation period, presumably from growth and development. ANOVA comparisons of total contacts of anterior and posterior teeth indicated statistically significant differences in the three groups on posterior segments. CONCLUSIONS The hypothesis is rejected. Both retention procedures allowed relative vertical movement of the posterior teeth, but the number of contacts on the posterior segment was increased more in the bonded retainer group than in the Hawley and control groups at the end of retention.