Ahmet Yagci

Dehiscence and fenestration in skeletal Class I, II, and III malocclusions assessed with cone-beam computed tomography

OBJECTIVE To test the null hypothesis that the presence of dehiscence and fenestration was not different among patients with skeletal Class I, II, and III malocclusions. MATERIALS AND METHODS In this retrospective study, a total of 123 cone-beam computed tomography (CBCT) images were obtained with an iCAT scanner (Imaging Sciences International, Hatfield, Pa). Patients with normal vertical patterns were classified according to dental malocclusion and ANB angle. Class I comprised 41 patients-21 girls and 20 boys (mean age, 22.4 ± 4.5 years); Class II comprised 42 patients-22 girls and 20 boys (mean age, 21.5 ± 4.2 years); and Class III comprised 40 subjects-22 girls and 18 boys (mean age, 22.1 ± 4.5 years). A total of 3444 teeth were evaluated. Analysis of variance and Tukeys test were used for statistical comparisons at the P < .05 level. RESULTS Statistical analysis indicated that the Class II group had a greater prevalence of fenestration than the other groups (P < .001). No difference was found in the prevalence of dehiscence among the three groups. Although fenestration had greater prevalence in the maxilla, more dehiscence was found in the mandible for all groups. In Class I, alveolar defects (dehiscence, fenestration) were matched relatively in both jaws. Furthermore, Class II and Class III subjects had more alveolar defects (41.11% and 45.02%, respectively) in the mandible. Dehiscences were seen with greater frequency in the mandibular incisors of all groups. CONCLUSION The null hypothesis was rejected. Significant differences in the presence of fenestration were found among subjects with skeletal Class I, Class II, and Class III malocclusions. Fenestrations had greater prevalence in the maxilla, but more dehiscences were found in the mandible.

Evaluation of speed, repeatability, and reproducibility of digital radiography with manual versus computer-assisted cephalometric analyses

The aims of this study were to evaluate intra-examiner repeatability and inter-examiner reproducibility of landmarks using two cephalometric analysing techniques, manual and computerized, and to compare these for speed. One hundred lateral cephalometric radiographs were randomly selected and 11 angular and six linear parameters were traced and measured by two examiners using the manual method and Dolphin Image Software 9.0 on each radiograph. A Students t-test for paired and independent samples was used to compare the mean values of intra- and inter-examiner differences. Intraclass correlation coefficients (ICC) were calculated to determine intra- and inter-examiner correlation (r value). Both operators were generally consistent in the repeated measurements; however, for one examiner, the differences for Na is perpendicular to A (P < 0.001), Na is perpendicular Pog, and U1-NA (P < 0.01) distance measurements were found to be statistically significant. Intra-examiner repeatability of landmarks both with the manual and Dolphin techniques showed high correlation coefficients. While inter-examiner reproducibility of landmarks was unacceptable, measurement errors with the manual technique were generally comparable with the Dolphin technique. The mean tracing times of the two operators for a single tracing was 2 minutes 41 seconds for Dolphin and 6 minutes 51 seconds for manual tracings. Computer-assisted cephalometric analysis does not increase intra- and inter-examiner reliability but can result in time saving.

Dehiscence and fenestration in patients with different vertical growth patterns assessed with cone-beam computed tomography

OBJECTIVE To test the null hypothesis that the presence of alveolar defects (dehiscence and fenestration) was not different among patients with different vertical growth patterns. MATERIALS AND METHODS A total of 1872 teeth in 26 hyper-divergent (mean age: 24.4 ± 4.8 years), 27 hypo-divergent (mean age: 25.1 ± 4.5 years), and 25 normo-divergent (mean age: 23.6 ± 4.1 years) patients with no previous orthodontic treatment were evaluated using cone-beam computed tomography. Axial and cross-sectional views were evaluated with regard to whether dehiscence and/or fenestration on buccal and lingual surfaces existed or not. For statistical analysis, the Pearson chi-square test was used at a P < .05 significance level. RESULTS According to the statistical analysis, the hypo-divergent group (6.56%) had lower dehiscence prevalence than the hyper-divergent (8.35%) and normo-divergent (8.18%) groups (P  =  .004). Higher prevalences of dehiscence and fenestration were found on buccal sides in all vertical growth patterns. While fenestration was a common finding for the maxillary alveolar region, dehiscence was a common finding in the mandible in all groups. CONCLUSION The null hypothesis was rejected. Although the prevalence of fenestrations was not different, significant differences for dehiscences were found in patients with different vertical growth patterns.

Standards of soft tissue Arnett analysis for surgical planning in Turkish adults

The aims of this study were (1) to establish standards for Arnett soft tissue cephalometric analysis of Anatolian Turkish young adults and (2) to identify possible gender differences between males and females. After analysing the cephalometric radiographs of 350 individuals, 133 subjects (67 males, mean age 22.6 +/- 2.2 years, and 66 females, mean age 22.1 +/- 2.6 years) with normal antero-posterior and vertical skeletal relationships were selected. The true vertical line was established. The landmarks were marked and soft tissue facial analysis was performed. For statistical evaluation, an independent-samples t-test was used. The lower lip thickness of the Turkish population was lower and menton thickness was greater than Arnetts norms. Turkish subjects have depressed orbital rims, cheek bones, subpupils, upright and thin upper and lower lips, retruded incisors, and pogonion and point B. Most of the Turkish mean harmony values were within the range of Arnetts harmony standards. Soft tissue thicknesses were greater and facial lengths, except upper incisor exposure, were longer in Turkish males than females. These differences between ethnic groups should be taken into consideration when formulating orthodontic/orthognathic treatment plans for patients with dentofacial deformity.

Ethnic differences in the soft tissue profiles of Turkish and European–American young adults with normal occlusions and well-balanced faces

The aim of this study was to evaluate soft tissue differences between Turkish and North American adults by comparing two sample populations with ideal occlusion and well-balanced faces. Lateral cephalometric radiographs of 117 Anatolian Turkish adults (65 female and 52 male, mean age: 23.9 ± 2.8 years) were compared with a sample of 116 adults of European-American ancestry (64 female and 52 male, mean age: 25.0 ± 6.8 years). The cephalometric analyses of Holdaway, Epker, and Legan and Burstone were performed using Dolphin Image Software 9.0. Thirty-two measurements (27 linear and 5 angular) were analysed. For statistical evaluation, independent samples t-tests were performed. Distinct differences were found between the two samples in facial convexity, upper lip position and length, lower lip position, chin prominence, and chin thickness. Vertical proportional findings were similar between groups. Ethnic differences were found between Turkish and North American adults in the soft tissue profile. It is appropriate to consider these differences during routine diagnosis and treatment planning of a Turkish patient or an American patient of European ancestry.

Influence of Pre-Orthodontic Trainer treatment on the perioral and masticatory muscles in patients with Class II division 1 malocclusion

The aim of this follow-up study was to evaluate the effects of Pre-Orthodontic Trainer (POT) appliance on the anterior temporal, mental, orbicularis oris, and masseter muscles through electromyography (EMG) evaluations in subjects with Class II division 1 malocclusion and incompetent lips. Twenty patients (mean age: 9.8 ± 2.2 years) with a Class II division 1 malocclusion were treated with POT (Myofunctional Research Co., Queensland, Australia). A group of 15 subjects (mean age: 9.2 ± 0.9 years) with untreated Class II division 1 malocclusions was used as a control. EMG recordings of treatment group were taken at the beginning and at the end of the POT therapy (mean treatment period: 7.43 ± 1.06 months). Follow-up records of the control group were taken after 8 months of the first records. Recordings were taken during different oral functions: clenching, sucking, and swallowing. Statistical analyses were undertaken with Wilcoxon and Mann-Whitney U-tests. During the POT treatment, activity of anterior temporal, mental, and masseter muscles was decreased and orbicularis oris activity was increased during clenching and these differences were found statistically significant when compared to control. Orbicularis oris activity during sucking was increased in the treatment group (P < 0.05). In the control group, significant changes were determined for anterior temporal (P < 0.05) and masseter (P < 0.01) muscle at clenching and orbicularis oris (P < 0.05) muscle at swallowing during observation period. Present findings indicated that treatment with POT appliance showed a positive influence on the masticatory and perioral musculature.

Does a chitosan-containing dentifrice prevent demineralization around orthodontic brackets?

OBJECTIVE To test the null hypothesis that there is no significant difference between the chitosan-containing and conventional nonfluoridated dentifrices in inhibition of enamel demineralization around orthodontic brackets. MATERIALS AND METHODS Sixteen orthodontic patients who were scheduled to have extraction of four first premolars for orthodontic reasons were divided into two groups after the power of the study was estimated. Patients in the experimental group were instructed to use chitosan-containing dentifrice (AloeDent), and patients in the control group were instructed to use nonfluoridated dentifrice (Sensodyne Mint). After 60 days, the teeth were extracted and longitudinally sectioned. The demineralization was assessed by cross-sectional microhardness. The determinations were made at the bracket edge cementing limits and at occlusal and cervical points, 100 µm and 200 µm away from the edge. In all these positions, indentations were made at depths of 10, 20, 30, 50, 70, and 90 µm from the enamel surface. Analysis of variance (ANOVA) and Tukey test were used for statistical evaluation at P < .05 level. RESULTS ANOVA showed statistically significant differences for the factors of dentifrice type, position, and depth (P  =  .000). Statistically significant differences for microhardness values between two tested dentifrices were observed up to 20 µm of depth from the enamel surface (P < .05). Lower microhardness values were found for nonfluoridated dentifrice. Significant microhardness differences were also determined between materials at occlusal and cervical 0 µm positions (P < .05). At these positions, chitosan-containing dentifrice showed lower demineralization than the control. CONCLUSION Chitosan-containing dentifrice may reduce the enamel decalcification found in patients with poor oral hygiene. The null hypothesis is rejected.

Genetic background of supernumerary teeth.

Supernumerary teeth (ST) are odontostomatologic anomaly characterized by as the existence excessive number of teeth in relation to the normal dental formula. This condition is commonly seen with several congenital genetic disorders such as Gardner′s syndrome, cleidocranial dysostosis and cleft lip and palate. Less common syndromes that are associated with ST are; Fabry Disease, Ellis-van Creveld syndrome, Nance-Horan syndrome, Rubinstein-Taybi Syndrome and Trico-Rhino-Phalangeal syndrome. ST can be an important component of a distinctive disorder and an important clue for early diagnosis. Certainly early detecting the abnormalities gives us to make correct management of the patient and also it is important for making well-informed decisions about long-term medical care and treatment. In this review, the genetic syndromes that are related with ST were discussed.

Effects of modified and conventional facemask therapies with expansion on dynamic measurement of natural head position in Class III patients

INTRODUCTION The aim of this prospective clinical trial was to assess the effects of varying force directions on the dynamic measurement of natural head position and orofacial airway dimensions of Class III patients during maxillary orthopedic protraction compared with an untreated control group. METHODS The conventional facemask group comprised 15 patients (8 girls, 7 boys; mean age, 9.6 ± 1.3 years), the modified facemask group comprised 15 patients (7 girls, 8 boys; mean age, 9.5 ± 1.5 years), and the control group comprised 15 subjects (7 girls, 8 boys; mean age, 9.8 ± 1.6 years). Natural head position measurements and cephalometric records were obtained from all subjects before and after treatment or the control period (approximately 1 year). An inclinometer and a portable data logger were used to collect the dynamic natural head position data. For statistical comparisons, paired samples t tests, analysis of variance (ANOVA), and post-hoc Tukey tests were used at the P <0.05 level. RESULTS Both treatment groups showed statistically significant changes in the sagittal (pitch) measurements of natural head position and upper pharynx, aerial, and total area of airway measurements during the treatment period. In the control group, the only statistically significant change was an increased upper pharynx measurement (P = 0.020). According to the intergroup comparisons, statistically significant natural head position differences were found in the conventional (6.4° flexion) and the modified (5.7° flexion) facemask groups when compared with the controls. The modified facemask group also showed significant changes in aerial (P = 0.003) and total (P <0.001) areas of the airway measurements compared with the control group. No statistically significant differences were observed between the 2 treatment groups. CONCLUSIONS These findings suggest that modified and conventional facemask therapy with expansion have significant cranial flexion effects on the dynamic measurements of natural head position. Additionally, the modified facemask procedure showed significant effects on the orofacial airway dimensions compared with the initial values and the values of the untreated controls.

Microleakage under orthodontic brackets bonded with the custom base indirect bonding technique

The aim of this in vitro study was to compare microleakage of orthodontic brackets between enamel-composite and composite-bracket interfaces at the occlusal and gingival margins, bonded using indirect bonding systems with that of a conventional direct bonding method. Forty freshly extracted human maxillary premolar teeth were randomly divided into two groups. In group 1, the brackets were bonded to teeth directly according to the manufacturers recommendations. Group 2 consisted of 20 teeth bonded indirectly with Transbond XT (3M-Unitek), as the adhesive, and Sondhi Rapid Set A/B Primer (3M-Unitek), a filled resin primer. After bonding, the specimens were further sealed with nail varnish, stained with 0.5 per cent basic fuchsine for 24 hours, sectioned and examined under a stereomicroscope, and scored for microleakage at the enamel-composite and composite-bracket interfaces from both the occlusal and gingival margins. Statistical analyses were performed using Kruskal-Wallis and Mann-Whitney U-tests with Bonferroni correction. The gingival sides of group 1 displayed a higher median microleakage score than the occlusal side at the enamel-composite interface but this was not statistically significant (P > 0.05). All occlusal margins in both groups showed no microleakage under orthodontic brackets at the enamel-composite or composite-bracket interfaces. Comparisons of the microleakage scores between the direct and the indirect bonding groups at the enamel-composite and composite-bracket interfaces indicated no statistically significant microleakage differences at the gingival and occlusal margins (P > 0.05). The type of bonding method (direct versus indirect) did not significantly affect the amount of microleakage at the enamel-composite-bracket complex.