Effects of different types of maxillary protraction on maxilla with finite element analysis.

OBJECTIVE: To compare two different skeletal anchorage methods with finite element analysis in the treatment of Class III patients with maxillary retrognathia. MATERIAL AND METHODS: Two different treatment scenarios were performed on skull model obtained from computerized tomography images of skeletal Class III patients with maxillary retrognathia and finite element analysis was performed. In the first group; mini plates were simulated on infra zygomatic crest. A unilateral 500 g protraction force was applied to the face-mask. In the second group; mini plates were simulated in infrazygomatic crest and mandibular symphysis. Then, 500g protraction force was applied with Class III elastic between the miniplates. Von Misses stresses and displacement values were evaluated comparatively. RESULTS: In Class III elastic group, maximum Von Misses stress occurred around infra zygomatic crest and symphysis anchored with 0.078 MPa. The maxillary posterior region and paranasal regions were the areas showing the highest Von Misses tension after infra zygomatic crest and symphysis. In the face-mask group, the most common site of Von Misses stress in nasomaxillary complex and alveolar structures were infra zygomatic area where plaques were applied, followed by pterygomaxillary suture. Tensile forces are reduced especially in these two areas by spreading to surrounding structures. CONCLUSIONS: In both methods, it was determined that the amount of force transmitted to circumaxillary sutures was sufficient to induce the formation of osteogenesis in these regions.

Determining the short-term effects of different maxillary protraction methods on pharyngeal airway dimensions.

OBJECTIVE: This study sought to evaluate the effects of different maxillary protraction methods on the pharyngeal airway in Class III patients with maxillary retrognathia. SETTING AND SAMPLE POPULATION: A total of 59 individuals (31 females and 28 males) with a mean age of 11.38 ± 1.24 years were included in this study. MATERIAL AND METHODS: Fifty-nine treated maxillary retrognathic patients who underwent different protraction methods were evaluated. Twenty patients treated with RME (Rapid Maxillary Expansion) made up the first group, and 20 patients treated with 5-week Alt-RAMEC (Alternate Rapid Maxillary Expansion and Constriction) protocol comprised the second group. Lastly, 19 patients on whom face masks with miniplates were applied were included in the skeletal anchorage (SA) group. Sixteen linear and four areal pharyngeal airway measurements were made on lateral cephalograms before and after treatment. Differences between the groups were assessed using analysis of variance (ANOVA) tests. RESULTS: The mean maxillary protraction levels were determined as 2.7, 3.69 and 4.01 mm in the RME, Alt-RAMEC and SA groups, respectively. In the nasopharynx, AD1-PNS, AD2-PNS, PNS-Ba and PNS-Ho measurements revealed a significant increase in the SA group compared to the other groups (P < .05). In the oropharynx, PNS-Ep measurement increased significantly in the RME group (P < .05). In the total pharyngeal airway area, an increase was detected in the SA, Alt-RAMEC, and RME groups. CONCLUSION: The most effective protraction method in terms of pharyngeal airway dimensions, especially in the nasopharynx, is the application of the face mask with skeletal anchorage. A greater increase in vertical airway length (PNS-Ep) was observed with RME.

Skeletal and Dental Effects of Twin-Block Appliances in Patients Treated With or Without Expansion.

OBJECTIVE: To compare the skeletal and dental effects of twin-block appliances with or without expansion. METHODS: From our archives, patients using twin-block appliances were selected. A total of 20 patients with expansion screws were classified as group 1 (10 male, 10 female; mean age 12.48 ± 1.38 years), and 18 patients without screws as group 2 (8 male, 10 female; mean age 12.81 ± 1.16 years). Cephalometric radiographs at pre-and post-treatment were used to evaluate skeletal and dentoalveolar parametric changes; study models and posteroanterior radiographs were used for transverse evaluation. The initial measurements and the treatment-related mean changes within the study groups were analyzed using the Student's t-test. RESULTS: Changes in maxillary skeletal measurements were not statistically significantly different between groups except for A-VRL (P > .05). Mandibular measurements showed an increase in SNB (º) and Co-Gn distance in both groups. However, these changes were similar for both groups (P > .05). The maxillary measurements showed that incisors were proclined in the expansion group and retroclined in the non-expansion group. No significant difference was found between the groups in terms of changes in the skeletal transversal measurements (P > .05). On the study models, the changes in maxillary intercanine and intermolar widths, and in arch length differed to a statistically significant degree between groups (P < .05). CONCLUSION: The skeletal effects of 2 different types of twin-block appliances in the transversal direction were similar; it was determined that dental expansion was obtained in the maxilla by adding screws to the twin-block appliances.

Comparison of three-dimensional soft-tissue evaluations between skeletal and pseudo-class III malocclusions.

The aim of our study was to compare soft tissue measurements with 3D imaging methods in individuals with untreated skeletal and pseudo-Class III malocclusions. The study sample consisted of 75 patients (38 males, 37 females, mean age 12.41 ± 2.35 years) with pseudo- and true skeletal Class III malocclusions and skeletal Class I malocclusions. Soft tissue evaluations of all patients were performed using 3D stereophotogrammetric facial images. In our study, 26 landmarks, 17 linear measurements, 13 angular measurements, and 5 volume measurements were made using the 3dMD Vultus software. The significance was determined to be p < 0.05 in ANOVA, Tukey tests. No significant differences were found among the groups in terms of demographic data (p > 0.05). The skeletal Class I control group had a significantly more extended upper lip and vermillion length as compared to the Class III groups. The soft tissue convexity angle and upper nasal angle were found to be wider in the Class III malocclusion group compared to those in the Class I control group. While the pseudo-Class III group had a significantly lower midface volume, chin volume was significantly higher in the skeletal class group. Upper lip volume was significantly higher in the Class I group. Using 3dMD for guiding clinicians in the differential soft and hard tissue diagnosis of pseudo-Class III malocclusions, differences were revealed in Class I patients in the middle part of the face. In the differential diagnosis of true Class III malocclusions, chin volume was found to be different from that of Class I patients.

Comparison of treatment effects of different maxillary protraction methods in skeletal class III patients.

OBJECTIVE: The aim of this study was to compare treatment outcomes with different maxillary protraction methods in patients with skeletal Class III malocclusion resulting from maxillary retrognathia. SETTING AND SAMPLE POPULATION: A total of 55 individuals consisting of 29 females and 26 males with a mean age of 11.4 ± 1.06 years were included in this study. MATERIAL AND METHODS: Fifty-five treated maxillary retrognathic patients who underwent different protraction facemask methods were evaluated. Eighteen patients treated with RME were in the first group, and 19 patients treated with a modified Alt-RAMEC protocol were in the second group; eighteen patients on whom face masks with miniplates were applied were included in the skeletal anchorage (SA) group. Thirty measurements were made on lateral cephalometric radiographs before and after treatment. Differences between the groups were assessed with the ANOVA test. RESULTS: The mean age was higher in the SA group (11.96 ± 0.92 years) compared with the other groups. The mean ANB angle increased by 2.96°, 4.91° and 3.86° in the RME, Alt-RAMEC and SA groups, respectively. The forward movement of the maxilla was similar between the groups. However, while the rate of protraction was higher in the modified Alt-RAMEC group, a greater skeletal effect was found in the SA group. CONCLUSION: The most effective method in terms of skeletal effect is the application of the face mask with skeletal anchorage; the modified Alt-RAMEC protocol can be applied before face mask to obtain faster protraction.

The reliability of the Greulich and Pyle atlas when applied to a Southern Turkish population.

OBJECTIVE: The aim of this study was to evaluate the applicability of Greulich and Pyle (GP) method for Southern Turkish population. MATERIALS AND METHODS: Hand and wrist radiographs of 535 patients (276 females, 259 males aged from 10 to 18 years) selected retrospectively from the archive. Skeletal age (SA) estimation was performed according to GP atlas. The chronological age (CA) and SA were compared using the Paired t-test. RESULTS: The mean difference between the CA and SA ranged from 0.07 to 1.11 years. These differences between the CA and estimated SA were statistically significant in group I (10-10.90 years) (P < 0.001), group II (11-11.90 years) (P < 0.050), group III (12-12.90 years) (P < 0.001), group IV (13-13.90 years) (P < 0.010), and group V (14-14.90 years) (P < 0.001) for females. The mean difference between the CA and SA ranged from -0.41 to -1.79 years for females. These differences between the CA and estimated SA were statistically significant in all age groups. CONCLUSIONS: Statistically significant differences were found in the CA and SA assessed by GP method for the Southern Turkish sample. SA was significantly over-predicted in the 10-15 year ages in males and for 10-18 year ages for females. It is appropriate to use GP method in Southern Turkish children; however, a revision is needed for better results and to minimize the mistakes.

Factors influencing the contraceptive method choice: a university hospital experience.

OBJECTIVE: To analyze the factors influencing behavior of women in choosing contraceptive methods. MATERIAL AND METHODS: A total of 4022 women who were admitted to our clinic in a year, were the subjects in this current study for contraception choices. Relationship between the current contraceptive choice and the age, marital status, educational level, gravidity and induced abortions were evaluated. RESULTS: Current users of any contraceptive methods were found to make up thirty-three percent of the entire study population. The most preferred method of contraception was an intrauterine device (46.4%), followed by, condom (19.2%), coitus interruptus (16.4%), tubal sterilization (11%), oral contraceptives (5.7%) and lastly the "other methods" that consisted of depot injectables and implants (1.2%). Among other contraceptive methods, the condom was found to be used mostly by the younger age group (OR:0.956, 95% CI:0.936-0.976, p<0.001), while tubal sterilization was preferred mainly by the elderly population (p<0.001, OR:1.091, 95% CI:1.062-1.122). Women that have a higher educational level, were found to use OC (76.3%, OR:5.970, 95% CI:3.233-11.022), tubal sterilization (59.6%, OR:4.110, 95% CI:2.694-6.271) and other methods (62.5%, OR:3.279, 95% CI:1.033-10.402) more commonly than the low educational group (p<0.001). CONCLUSION: These results demonstrated that the rates of both contraception utilization and the usage of more effective methods of contraception need to be increased by providing better family planning systems and counselling opportunities.