Variations in Function and Vocal Acoustic Characteristics After Orthognathic Surgery: Preliminary Results

Objective: To determine the effects of orthognathic surgery on oral function and vocal quality in order to assess the need for speech therapy after surgery. Material and Methods: Thirty-seven patients scheduled for mono-jaw surgery, specifically maxillary (G1:15 patients), mandibular advancement (G2:10 patients) or mandibular set-back (G3:12 patients), were recruited for this prospective cohort study. Evaluation of oral functions, video recordings of speech articulation and audio recordings of voice were obtained before surgery (T0), and at 1 (T1) and 6 months (T2) after surgery. Spectrographic analysis and self-evaluation questionnaire regarding the vocal performance (VAPP) were performed. Both qualitative and quantitative statistical analysis was performed, mainly using generalized linear models for dichotomous data (p<0.05). Results: The formant frequencies (F1 and F2) of the main vowels vary after orthognathic surgery according to the type of surgery. Before surgery, 84% of patients analyzed showed difficulties in breathing and positioning the tongue both at rest and swallowing. Thanks to surgical correction of the malocclusion, the major part of these issues were resolved within 6 months. In 25% of cases, a change in the voice and/or articulation had occurred. Conclusion: Vocality improves after orthognathic surgery and it changes in relation to the type of surgery. However, vocality did not normalize completely. Speech assessment should be considered after surgery in order to offer adequate speech therapy if necessary.&nbsp

3D Assessment of the Correlation between Neonatal Morphology and Occlusal Outcomes in 5-Year-Old Patients with Complete Unilateral Cleft Lip and Palate

Objective: To exploit 3D measurement technology to determine any correlation between neonatal palate morphology and occlusal outcomes at five years in patients receiving surgery for unilateral cleft lip and palate (CLP). Material and Methods: Twenty-nine neonatal and 5-year models treated by the same surgeon using the same protocol for CLP correction were scanned using a high-resolution structured-light scanner and stored in stl format. Dedicated software was used to make linear and surface area measurements on the neonatal models, and each digitized 5-year model was assigned a Five-Year-Old (5YO) index score on three separate occasions by the same investigator. Results: Minimum, maximum, mean, standard deviation and standard error were calculated for each variable considered, and the Pearson coefficient was used to identify any correlations between neonatal variables and 5YO scores. Linear regression analysis showed that the only variable to approach significance was the posterior width of the cleft, which showed an R2 equal to 0.111, indicating that it accounts for 11% of the variability of the 5YO index. There was no other appreciable correlation between linear measurements, surface areas, or their inter-relationships. Conclusion: There is no correlation between neonatal morphological characteristics and occlusal outcomes at 5 years in CLP patients treated via the surgical protocol considered

Accuracy Assessment of Virtual Surgical Planning Comparing 3D Virtual Surgical Planning and Post-Operative CBCTs in Surgical Skeletal Class III Cases: A Retrospective Study

Objective: To evaluate the accuracy of Virtual Surgical Planning (VSP) comparing VSPs and post-operative CBCT scans in patients undergoing bimaxillary orthognathic surgery of severe Skeletal Class III malocclusion. Material and Methods: Twenty-three patients (9 males and 14 females, mean age 24.1 ± 7.0 years) were selected and submitted to bimaxillary orthognathic surgery. Pre-operative VSPs and post-operative CBCTs were compared using both linear (taking into account four skeletal and six dental landmarks, each one described by the respective coordinates) and angular measures (seven planes in total). The threshold discrepancies for post-operative clinical acceptable results were set at ≤2 mm for liner and ≤4° for angular discrepancies. The mean difference values and its 95% confidence interval were identified, comparing which planned and which obtained in absolute value. Results: There were significant statistical differences for all absolute linear measures investigated, although only two overcome the linear threshold value of 2mm in both X and Y-linear dimensions. Linear deviations in Z-linear dimension do not reach statistical significance. All 12 angular measures reach the statistical significance, although none overcome the threshold angular value of 4°. Angular deviation for roll register the higher accuracy in contrast to pitch and yaw. Conclusion: Virtual surgical planning is a reliable planning method to be used in orthognathic surgery field; as a matter of fact, although some discrepancies between the planned on the obtained are evident, most of them meet the tolerability range

Long-term stability of alveolar bone grafts in cleft palate patients

Introduction: Many authors have examined the surgical bone treatment of cleft palate patients, but no study has emphasized the role of orthodontic therapy. The aims of this study were to evaluate the long-term stability of bone grafts when using an orthodontic-surgical protocol, to determine the success of bone grafts in minor vs severe clefts, and to develop a qualitative method for assessing the success of bone grafting. Methods: Forty-nine pa- tients were included in this study. Occlusal x-rays were taken before (T0), immediately after (T1), and at least 1 year after bone grafting (T2). Two radiographic parameters were analyzed adjacent to the cleft side: the vertical bone level (Bergland scale) and the horizontal bone level (Witherow-derived scale). Results: The bone graft success at T2 was 91.84% (95% confidence interval, 84.55-96.41). The severity of the cleft before grafting was not statistically correlated with success at T2 (P \0.05). The concordance rate between Bergland and With- erow values was 87.07% (95% confidence interval, 82.69-90.69). The variables analyzed (sex, age, type of cleft, lateral incisor agenesis) were not statistically correlated (P \0.05) with the stability of bone graft. Based on the results, the only factor involved in the stability of the graft seems to be dental age at the time of bone grafting and the orthodontic therapy before and after grafting. Conclusions: It seems appropriate to recommend early appli- cation of a surgical-orthodontic protocol to treat cleft lip and palate patients, prevent postoperative bone resorption, and guarantee correct positioning of the teeth. (Am J Orthod Dentofacial Orthop 2012;142:289-99

The Accuracy of Jaws Repositioning in Bimaxillary Orthognathic Surgery with Traditional Surgical Planning Compared to Digital Surgical Planning in Skeletal Class III Patients: A Retrospective Observational Study

Background: Technological progress has led to the transition to digital methods to perform surgical planning and to obtain surgical splints with CAD/CAM technologies. The present study aimed to compare the accuracy of jaw repositioning in bimaxillary orthognathic surgery using traditional and digital surgical planning in skeletal class III patients. Methods: This study included 60 skeletal class III patients divided into two groups based on the method used to perform surgical planning: traditional (T, n = 30) and digital (D, n = 30). For each patient, a 2D presurgical Visual Treatment Objective (VTO) was prepared and the outcome of the surgery was compared with that planned by using determined cephalometric measurements (ANB, SNA, SNB, Ar-Go-Me, S-Ar-Go). Statistical analysis showed that the measurements planned and those obtained after surgery were equivalent in Group D. For Group T, the analysis showed equivalence only for one of the considered measurements (ANB). By comparing the results of the two groups, Group D presented a lower level of error than Group T. Conclusions: Digital surgical planning performed significantly better in terms of accuracy of jaw repositioning than the traditional protocol

Suggestive linkage between markers on chromosome 19q13.2 and Nonsyndromic orofacial cleft malformation

Nonsyndromic cleft lip with or without cleft palate (OFC) is a common birth defect that has genetic bases. The nature of the genetic contribution is still to be clarified; however, some chromosome regions and candidate genes have been proposed for this malformation. We examined linkage between BCL3, a protooncogene located in 19q13.2, and OFC in a sample composed of 40 multiplex pedigrees using both nonparametric and parametric methods. The affected pedigree member statistics and the transmission disequilibrium test supported a role for BCL3 in causing OFC, while no evidence of linkage or genetic heterogeneity was found with the lod score method

The Accuracy of Jaws Repositioning in Bimaxillary Orthognathic Surgery in Patients with Cleft Lip and Palate Compared to Non-Syndromic Skeletal Class III Patients

Background: The present study aims to compare the accuracy of jaw repositioning in bimaxillary orthognathic surgery using digital surgical planning in cleft lip and palate patients and in non-syndromic skeletal class III patients in order to investigate if orthognathic surgery achieves different results in the first group of patients. Method: This study included 32 class III adult patients divided into 2 groups: cleft lip and palate (A, n = 16) and non-cleft (B, n = 16). For each patient, a 2D pre-surgical visual treatment objective was performed by the surgeon to predict hard tissue changes, and the surgical outcome was compared with that planned by using cephalometric measurement (ANB, SNA, SNB, Ar-Go-Me, S-Ar-Go). The statistical analysis showed equivalence between obtained and planned results for each measurement both in group A and in group B, but the difference between the planned and the obtained result was smaller in group B regarding ANB angle. Conclusions: Digital surgical planning ensures better predictability of the surgical results and higher accuracy of surgery in complex patients, such as those with cleft lip and palate