Evren Öztaş

Oropharyngeal airway changes following bimaxillary surgery in Class III female adults.

AIM The aim of this study was to evaluate oropharyngeal airway changes following Le Fort I maxillary advancement and impaction with mandibular setback in Class III deformity. SUBJECTS AND METHODS 53 female Class III patients (mean age: 24.9+/-0.8 years) had Le Fort I maxillary advancement with impaction, and mandibular setback osteotomies. Lateral cephalograms were taken before (T0), one week postoperatively (T1) and 1.3+/-0.2 years after (T2) bimaxillary surgery. Paired t and Pearson tests were used to evaluate the changes. RESULTS The mandibular plane-hyoid, upper retropalatal airway space (URP) and hyoid to horizontal reference plane (HY-HOR) distances significantly increased and the third vertebra to menton, hyoid to vertical reference plane (HY-VER) distances decreased in the T0-T1 period. Relapses were found in mandibular plane to hyoid (MP-HY), URP, HY-HOR, third cervical vertebra to menton (C3-Me) and HY-VER distances in T1-T2 period. Correlations were found between the mandibular retraction and increases of the narrowest retropalatal (r: 0.29, p<0.05) and lowest retropalatal airway spaces (r: -0.30, p<0.05) and posterior movement of hyoid (r: 0.60, p<0.001). CONCLUSIONS Bimaxillary surgery caused an increase in the URP, together with posterior and inferior movement of hyoid bone one week postoperatively. Some relapse was found in these changes over one year later.

Changes in soft tissue profile after mandibular setback surgery in Class III subjects

The aim of this study was to investigate changes in hard and soft tissue profile after mandibular setback surgery. Lateral cephalograms of 25 Class III subjects were assessed before and 1.5+/-0.4 years after mandibular setback surgery. Paired t test, Pearson correlation test and linear regression analysis were used to evaluate the changes in soft tissue profile. Significant changes were found in skeletal (SNB -3.6+/-0.9 degrees, ANB 3.7+/-1.0 degrees, overjet 5.0+/-1.2 and overbite 2.5+/-1.1 mm, P<0.001), soft tissue (facial convexity 5.9+/-1.6 degrees, P<0.001; labiomental fold 0.6+/-0.6 mm, P<0.001; upper and lower lip protrusion 0.5+/-0.8 mm, P<0.01; -3.3+/-1.2 mm, P<0.001), and upper and lower lip lengths (0.9+/-1.2mm, P<0.01; -1.8+/-2.1 mm, P<0.001). Correlations were found between facial convexity and SNB and ANB angles and between upper lip length and SNB and ANB angles. The change in lower lip length was correlated with SNB, ANB, overjet and overbite. Lower lip retrusion was correlated with overjet and a significant correlation was found between the retrusion of lower incisor and lower lip. Mandibular setback surgery was effective in producing an orthognathic profile in adult Class III subjects with mandibular prognathism.

Changes in head posture and hyoid bone position in Turkish Class III patients after mandibular setback surgery

The aim of this study was to determine the changes in head posture and hyoid bone position after mandibular setback osteotomy in Turkish adult Class III patients. Serial lateral cephalograms of 42 Turkish Class III patients (24 female, 18 male patients, mean age: 25.4+/-1.2 years) who underwent mandibular setback surgery were evaluated preoperatively, 1.2+/-0.6 years, 2.3+/-0.8 and 4.2+/-0.9 years postoperatively. A mean mandibular setback of 5.6+/-0.8mm was associated with a posterior and inferior movement of the hyoid bone and a significant flexion in the neck posture. Surgical correction of mandibular prognathism altered the position of the hyoid bone by downward repositioning carrying the root of the tongue downwards immediately postoperatively, but followed with a tendency to return to its original position.

Evaluation of the Effects of Temporomandibular Joint Disk Displacement and Its Progression on Dentocraniofacial Morphology in Symptomatic Patients Using Lateral Cephalometric Analysis

Abstract The aim of this study was to evaluate the effects of disk displacement (DD) and its progression on dentocraniofacial morphology in symptomatic patients and compare the results with asymptomatic volunteers. Skeletal and dental Class I female patients with DD, diagnosed using magnetic resonance imaging (MRI) and lateral cephalometric analysis were included in the study. Subjects were grouped as follows: control group with bilateral normal disk position (group 1, n=12), unilateral DD with reduction (group 2, n=16), bilateral DD with reduction (group 3, n=26), unilateral DD without reduction (group 4, n=12), and bilateral DD without reduction (group 5, n=8). Thirty-two (32) cephalometric variables were measured, and statistically significant differences were found in 11. Dental and soft tissue measurements did not reveal any differences, but variables related to the mandible showed statistically significant differences. Progression of DD was associated with an increase in all angular measurements related to vertical skeletal relationships and articular angle and a decrease in the ratio of posterior face height to anterior face height indicating clockwise rotation of the mandible. Similarly, the height of ramus was decreased with the progression of DD. The results of this study demonstrated that the presence of DD in skeletal Class I female patients effects facial morphology, and its progression makes the differences more significant and remarkable. These results emphasize the importance of early diagnosis and treatment in the management of DD.

An adult case of temporomandibular joint osteoarthritis treated with splint therapy and the subsequent orthodontic occlusal reconstruction.

Herein we report treatment for a 19-year-old female patient with severe osteoarthritis of the temporomandibular joint. The patient had severe open bite with a Class II molar relationship. She had limited mouth opening and pain. Clinical examination and magnetic resonance imaging revealed that she had anterior disc displacement without reduction. By splint therapy, limited mouth opening and pain was eliminated, but an anterior open bite developed after the treatment. By orthodontic treatment, an acceptable occlusion was achieved with a Class I molar relationship.

Analysis of temporomandibular joint sounds in orthodontic patients

Abstract In this work, we investigate the progress of temporomandibular joint (TMJ) sounds during orthodontic treatment. The study of changes in TMJ sounds might help to determine whether there are relations between various types of sounds and the dental malocclusions. TMJ vibrations from patients with lateral cross-bite and Class II Division 1 malocclusions are recorded by means of accelerometers during jaw opening and closing cycles. Then signals are analyzed using the discrete evolutionary transform. Joint time–frequency moments calculated from the evolutionary spectrum are used as features for the classification of TMJ vibrations by a neural network. Signals are classified at different stages of treatment and the results are discussed.

Evaluation of the closest speaking space in different dental and skeletal occlusions

STATEMENT OF PROBLEM The closest speaking space (CSS) together with the vertical overlap of anterior teeth during the production of the /s/ sound have not been previously investigated with respect to differences in dental and skeletal orthodontic classifications. PURPOSE The purpose of this study was to investigate the CSS in dental and skeletal occlusions and to analyze the cause and effect relationship of the CSS and the amount of the vertical overlap of anterior teeth. MATERIAL AND METHODS Poly vinylsiloxane interocclusal registration material was placed bilaterally onto the occlusal surfaces of premolar and molar teeth of 155 native Turkish speaking adolescent and young adult dentate participants, who were then asked to pronounce the word seyis. The thinnest point between the maxillary and mandibular teeth was recorded in millimeters as the CSS. The occlusion of each participant was classified according to the Angle dental and Steiner skeletal classifications. The differences in CSS values within each classification were statistically analyzed with the Kruskal-Wallis test, and the correlation between the CSS and the vertical overlap was statistically analyzed with the Spearman Rho Correlation tests (P<.05). RESULTS The differences in the CSS were only significant between Angle Class II division 2 and Class III groups (P=.034), while the differences in the CSS between skeletal classes were not significant. The correlation between the amount of CSS and the amount of vertical overlap was not significant. CONCLUSIONS The results showed that regardless of dental and skeletal occlusions, average CSS values could be used to determine the occlusal vertical dimension of prosthetic restorations.

Microhybrid versus nanofill composite in combination with a three step etch and rinse adhesive in occlusal cavities: five year results

Objectives The aim of the study was to evaluate the 5-year clinical performance of occlusal carious restorations using nanofill and microhybrid composites, in combination with 3-step etch-and-rinse adhesives, in patients who were going to commence orthodontic treatment. Materials and Methods A total of 118 restorations for occlusal caries were conducted prior to orthodontic treatment. Occlusal restorations were performed both with Filtek Supreme XT (3M ESPE) and Filtek Z250 (3M ESPE) before beginning orthodontic treatment with fixed orthodontic bands. Restorations were clinically evaluated at baseline and at 1, 2, 3, 4, and 5-year recalls. Results None of the microhybrid (Filtek Z250) and nanofill (Filtek Supreme XT) composite restorations was clinically unacceptable with respect to color match, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, or surface texture. A 100% success rate was recorded for both composite materials. There were no statistically significant differences in any of the clinical evaluation criteria between Filtek Z250 and Filtek Supreme XT restorations for each evaluation period. Conclusions The composite restorations showed promising clinical results relating to color matching, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, and surface texture at the end of the 5-year evaluation period.

MAXILLARY INCISOR TRAUMA IN PATIENTS WITH CLASS II DIVISION 1 DENTAL MALOCCLUSION: ASSOCIATED FACTORS

Purpose: The aim of this study was to assess the association between the presence of maxillary incisor trauma (MIT) with age, gender, dentition type, the degree of overjet (OJ), lip form, respiratory type and dental arch form in patients with Class II division 1 dental malocclusion. Subjects and Methods: 256 patients (mean age: 15.80 ± 2.2) were included in this study. The patients’ gender, dentition type, superior lip form, dental arch form and respiratory type were recorded. Participants were divided into four groups according to the severity of OJ: 3.5 mm<Group 1 (OJ I) ≤6 mm with competent lip, 3.5 mm<Group 2 (OJ II) ≤ 6 mm with incompetent lip, 6 mm<Group 3 (OJ III) ≤9mm, 9 mm<Group 4 (OJ IV). Mann Whitney-U test was used to examine the group differences for trauma and non-trauma groups. Logistic regression analysis was used to assess the factors for trauma and their risk indicators. Results: 3.5 mm<OJ II≤ 6 mm with incompetent lip had the highest odds of experiencing MIT among the OJ groups with an odds ratio (OR) of 3.143 and 95% confidence interval (CI) 1.125-2.779. The odds were 3.572 times higher in the group with short lip form than found in the group with normal lip form (OR 3.572, 95% CI 1.130-2.340). Conclusion: The age, gender, respiratory type and dental arch form were not significantly associated the risk of MIT. OJ between 3.5 mm and 6 mm (with incompetent lip) and short lips increased the risk of having maxillary incisor trauma in patients with Class II division 1 malocclusion.