MATERIALS AND METHODS: Over a period of 10 years (1989 to 1999), 34 patients with dentofacial deformities who had orthognathic surgery were reviewed; patients with cleft lip and palate or syndromes were excluded.
RESULTS: The mean age (range, 17 to 35 years) of the patients was 24.3 years and the ratio of female to male was 2.4:1. The predominant ethnic group was Chinese, with females (47.1%) forming the largest group. The main reason for seeking surgery was aesthetic improvement (41%). The majority of the patients had skeletal class III pattern (91%) and bilateral sagittal split osteotomy was the most common surgery done (82%). Postoperative complications were mainly paraesthesia/numbness (56%) and infection (15%). In long-term review, 2 (6%) patients had persistent numbness of the inferior alveolar nerve.
CONCLUSION: The findings suggest that the majority of the patients are young adult female students with skeletal class III pattern and treated for mandibular prognathism. The complication of persistent numbness and higher rate of postoperative infection indicate that longterm reviews and good antibiotic prophylaxis/therapy are necessary.
OBJECTIVE: To evaluate and compare the treatment effect of Reverse Twin-Block (RTB) and Reverse Pull Face Mask (RPFM) on Pharyngeal Airway Space (PAS) in early and late mixed dentition Class III samples.
METHODS: Ninety-five mixed dentition Malay children with Class III malocclusion were included in this study. Data consists of 190 pre- and post-treatment lateral cephalograms of early (8-9 years) and late (10-11 years) mixed dentition Class III samples. forty-nine samples were under RTB and forty-six samples were under RPFM. Treatment changes were evaluated by McNamara airway analysis and changes in tongue and hyoid bone position.
RESULTS: Both upper and lower pharyngeal airway width were increased after treatment with RTB and RPFM ruling out the chance of airway constriction. There was also posterior positioning of the tongue and hyoid bone indicating mandibular retrusion. No significant treatment changes were found on the Pharyngeal Airway Space by the factor age, gender or type of appliance.
CONCLUSIONS: Both RTB and RPFM increased the Pharyngeal Airway Space and produced similar treatment effect. As age does not affect the treatment outcome significantly, treatment can be delayed until late mixed dentition stage.
METHODS: A total of 208 CBCT images were examined retrospectively. Prevalence of an extra root/canal and internal morphology based on Vertucci's classification were observed in human maxillary and mandibular permanent teeth. Variations in the external and internal morphology were compared in relation to gender and tooth side (left vs right) using Pearson Chi-square and Fisher's exact tests with significance level set at p
METHODS: Data consisted of pre- and post-treatment lateral cephalograms of 95 children, 49 patients with RTB and 46 patients with RPFM, divided into an early (8-9 year) and late (10-11 year) group. Treatment changes were assessed by the Ricketts analysis using CASSOS software, where 71 anatomic landmarks were identified in each cephalogram. Paired and independent t tests were performed for statistical comparison.
RESULTS: Paired t test revealed significant changes in facial axis, facial angle, MD plane to FH, lower facial height, mandibular arc, maxillary convexity, U1 to APog, L1 to APog, L1 to APog angle and upper lip to E-plane measurements in RPFM, whereas significant changes were found in facial taper, U1 to APog and lower lip to E-plane values with RTB in the early treatment group. Independent t test revealed significant changes in U1 to APog, L1 to APog and U6 to PtV values in the RTB group. Post-treatment comparison of RTB and RPFM showed significant differences in L1 to APog and L1 to APog angle values.
CONCLUSIONS: RPFM revealed more favourable craniofacial changes than RTB, particularly in the late mixed dentition stage.