Maxillary dentoskeletal changes 1-year after adenotonsillectomy

Objective:To measure the maxillary dentoskeletal and soft tissue changes of severely obstructed mouthbreathing (MB) young children who had their mode of breathing normalized after adenotonsillectomy(T&A), in comparison with a matched group of severely obstructed untreated MB children (CG).Methods:Seventy patients who had an Ear, Nose, and Throat examination (ENT), including flexible nasalendoscopy, to confirm the severe obstruction of the upper airways and the indication of T&A composedthe sample. Cephalograms and dental casts were available from the patient’s orthodontic records. Treat-ment group (TG) and CG included 35 children each. Groups were matched by gender (24 males and 11females in each group), age (TG, 6.7±1.8 years; CG, 6.9±2.3 years), tooth development (TG, 13 primarydentition, 22 mixed dentition; CG, 14 primary dentition, 21 mixed dentition), and skeletal maturationstatus. Records were taken at baseline (T0) and 1-year after T&A (T1) for TG; while CG records were takenwith a 1-year interval. Dentoskeletal measurements were performed in the lateral cephalograms, anddental casts were used to assess the palatal volume and occlusal changes.Results:TG showed a significant increase (503.3 mm3,P<0.001) in the palatal volume (10% of change),while CG palatal volume was stable. No dimensional occlusal changes were detected between T0 andT1 in both groups. Significant downward (point A, 2.1 mm; ANS, 2.1 mm) and forward displacements (pointA, 0.7 mm; ANS, 1 mm) of the anterior region of the maxilla were observed in the TG, but CG presentedonly significant downward displacement (point A, 1.8 mm; ANS, 1.4 mm). The maxillary posterior region(PNS, PTM, and Molar) displaced downward in both groups (P<0.05), however no sagittal change wasfound. The palatal plane inclination was stable in both groups.Conclusions:TG presented significant increase in the palatal volume and in the forward displacementof the maxilla. No other significant maxillary dentoskeletal changes were found

Development and validation of a prediction model for long-term unsuccess of early treatment of Class III malocclusion

Aim To develop and validate a prediction model to forecast long-term stability of early treatment with rapid maxillary expansion (RME) and facemask (FM) in a large sample of Class III growing patients. Methods The Brazilian Group (BG) consisted of 73 consecutively treated Caucasian Class III patients (41 females and 32 males). Mean age at T0 (before treatment) was 7.1 ± 1.6 years, while mean age at T1 (long-term follow-up) was 21.8 ± 3.2 years. The Italian Group (IG, validation cohort) comprised 28 consecutively treated Caucasian Class III patients (14 females and 14 males, mean age at T0 9.0 ± 1.3 years and mean age at T1 18.2 ± 1.4 years). Cephalometric analysis was performed on lateral cephalograms at T0. Gender and cephalometric variables, chronologic age, and dentition phase at T0 were used as predictors for long-term unsuccessful treatment at T1. All predictors for unsuccessful treatment in the BG were subjected to bivariate logistic regression. Only those statistically significant predictors in the bivariate logistic regression entered mixed stepwise logistic regression with P = 0.05 to enter and to leave. The validity of the prediction model derived from the BG was then tested on the IG. Results The prediction model consisted of only one cephalometric variable: the angle between the Condylar Axis and the Mandibular Plane (CondAx–MP) (odds ratio: 1.52, 95% confidence interval: 1.25–1.85, P < 0.0001). Unsuccessful treatment at T1 was predicted for values of CondAx–MP at T0 greater than the cut-off value of 147.8 degrees. BG patients predicted incorrectly were 3 out of 22 for the unsuccessful cases and 1 out of 51 for the successful cases. Therefore, accuracy was 0.95, sensitivity 0.86, specificity 0.98, and positive and negative predictive values were 0.95 and 0.94. When the predictive model was applied on IG, all five unsuccessful cases were predicted correctly, while only 1 out of 23 successful patients was predicted incorrectly. Conclusion CondAx-ML was identified as a reliable predictor for long-term stability of early Class III treatment with RME and FM