Contributions of Digital Simulation to Orthodontic Therapeutic Decision-Making: A Case Report.

Adult orthodontics aims to achieve optimal functional and aesthetic corrections. However, for several reasons, some patients will wish to benefit from a limited treatment where only certain aspects of a malocclusion will be corrected. In these clinical situations, the therapeutic objectives must be adjusted to the individual needs of the patient insofar as they can bring them real benefits. The use of digital technology makes it possible to study the therapeutic possibilities better and visualize the occlusal results before choosing the best therapeutic approach, especially in cases requiring customization. The aim of this clinical case report is to illustrate the orthodontic compromise made after the analysis of the digital setup in an adult patient who presented with a class III malocclusion but refused orthodontic-surgical therapy and requested an alternative treatment.

Accuracy of hard and soft tissue prediction using three-dimensional simulation software in bimaxillary osteotomies: A systematic review.

INTRODUCTION: Orthognathic surgery is considered nowadays as a revolutionary treatment option for treating skeletal discrepancies and severe malocclusions in the sagittal, vertical and transverse dimensions. This surgery allows both the restoration of facial harmony and the achievement of satisfactory dental occlusion. The technology of computer-assisted surgeries including virtual surgical simulation programs and planning software greatly contributes to providing a three-dimensional simulation and precise mobilization of the maxilla and/or mandible, thus allowing the prediction of the final outcome in soft tissues. This study aims to systematically review the available scientific literature about the accuracy of the hard and soft tissue predictions delivered by the many promoted three-dimensional simulation software. MATERIAL AND METHODS: An electronic search was conducted on various databases: Medline via PubMed, The Cochrane Library, EBSCO-host, and Web of Science. The search was established on a well-defined research question following PICO principle: population, intervention, comparator and outcome. Search evaluation and the assessment of risk of bias were undertaken in each study following its type and design. RESULTS: Fifteen studies were included for qualitative analysis. Seven studies evaluated the accuracy of soft tissue prediction, seven focused more on the accuracy of hard tissue and one study assessed both hard and soft tissue prediction accuracy delivered by the simulation software. Moreover, three studies were judged to be low risk and four were classified as high risk. Included studies revealed that hard tissue prediction is highly accurate and reliable, leading to clinically acceptable results. Yet, soft tissue prediction is unclear due to various factors that bias its results. Caution should therefore be taken when providing information about the soft tissue planning to patients. CONCLUSIONS: Computer assisted 3D simulation protocols allow for more precise repositioning of the maxilla and/or mandible compared to conventional 2D methods. However, 3D soft tissue prediction using simulation software remains less accurate, especially in the labial region.

Perception of smile aesthetics between orthodontists and Moroccan patients.

Introduction: One of the main goals of orthodontic management is to achieve a beautiful smile. However, beauty has both objective and subjective dimensions. This study aims to evaluate the factors that affect the perception of the smile in patients consulting for orthodontic treatment about the vision of their practitioners. Materials and Methods: Fifty orthodontic patients and 30 orthodontists evaluated the degree of attractiveness of 16 photographs of the smile. Dental, gingival and labial parameters were used. Statistical analyses of the level of perception of each group were performed. The Student t-test and the Chi-square test were used to compare the attractive and unattractive smile parameters. Results and Discussion: The perception of smile aesthetics between orthodontists and orthodontic patients has shown a significant difference (P < 0.05). Orthodontists were more analytical in judging variables like smile arc, alterations of the gingival display and the palatal inclination of the maxillary incisors.

[Impact of incisor repositioning on the cephalometric position of points A and B]. / Le repositionnement incisif: quel impact sur la position céphalométrique des points A et B?

Introduction: points A and B are bony landmarks used in cephalometric studies to assess sagittal ratio between maxilla and mandible. The purpose of this study is to assess the reliability of points A and B as bony landmarks, by investigating the role of incisor repositioning on their cephalometric position. Method: superposition of cephalometric tracings at beginning and end of treatment of 30 patients without bone growth disorders, presenting with biproalveolia and having undergone orthodontic treatment with extraction of four first premolars was carried out to estimate changes in points A and B position. The significance threshold was set at 0.05. Results: our study showed that the influence of orthodontic treatment on point A position was not statistically significant, while its influence on point B position was statistically significant (p= 0,01). Indeed, for every 1mm of incremental repositioning, point B moved back by 0.17mm. Conclusion: incisor repositioning in the mandibular arch induces a change in the position of point B backwards.

Comparison of dentoalveolar protrusion values in Moroccans and other populations.

SUMMARY: The aim of this retrospective study was to evaluate bimaxillary protrusion among Moroccans and to compare the Moroccan population with other Arabic, Caucasian, and Mediterranean populations. Cephalometric radiographs of 102 Moroccan adult university students (73 females and 29 males, mean age: 21 years 6 months +/- 1 year 6 months) with a normal occlusion were traced. Fifteen measurements concerning the upper and lower incisors, upper and lower lips, and the Frankfort to mandibular plane angle were assessed. Statistical analysis of the data was undertaken using independent t-tests. Eight angular and six linear measurements were statistically significantly different compared with Caucasian cephalometric norms (P < 0.001). Significant differences were observed compared with other adult Arabic populations (Palestinians and Saudis) and with Turkish Anatolian adults. Relative to Caucasian cephalometric norms, Moroccans showed bimaxillary protrusion and, therefore, these norms cannot be applied to Moroccan faces. In general, there was a great similarity in incisor position between the Moroccan and Saudi populations.

A predictive model of advancement genioplasty in Class III bimaxillary surgical cases.

INTRODUCTION: The aim of our study was to try to standardize the surgeon's clinical sense in order to avoid revision surgery. MATERIALS AND METHODS: Twenty-nine patients with skeletal Class III treated by bimaxillary surgery were selected according to inclusion and exclusion criteria. These patients were divided into two groups according to the type of surgery: Group 1 (G1): bimaxillary surgery alone, and Group 2 (G2): bimaxillary surgery with genioplasty. The study was conducted based on the presurgical (t0) and postchirurgical (t1) lateral cephalograms. The different changes were compared between the two groups using the Mann-Whitney Test. One way and multiple linear regression analyses were used to determine the variables influencing the amount of displacement of the chin fragment during the genioplasty procedure. The significance level was fixed at 0.05. RESULTS: The labiomental profile was significantly more improved in group G2 (bimaxillary surgery with genioplasty), the aesthetic changes included the thickness increase of the lower labial sulcus and soft tissue pogonion, and also the reduction of the labiomental angle (P<0.05). Only the presurgical value of the labiomental angle would influence the amount of chin displacement. Starting from the regression analysis, we suggested a predictive equation allowing to predict this amount of displacement, based on the presurgical value of the labiomental angle. CONCLUSION: The analysis of changes (specifically the aesthetic ones) between the two groups of patients, allowed the proposal of a model predicting the amount of chin displacement performed in genioplasty group, based on the presurgical parameters. This model could contribute to determine an indicative value for bimaxillary surgery with additional genioplasty.

Orthodontics and enamel demineralization: clinical study of risk factors.

UNLABELLED: The appearance of white spots on the vestibular surface of teeth fitted with brackets has been described as one of the potential iatrogenic effects of orthodontic treatment. These enamel demineralizations, more commonly known as "white spot lesions" (WSL), lead in some rare cases to the creation of true cavities, causing both esthetic and functional problems. The aim of our retrospective clinical study was to evaluate the incidence of the appearance of these WSL in a Moroccan orthodontic population and to determine possible associations with a number of risk factors. PATIENTS AND METHODS: The study was based on intraoral photographs of a pool of 69 patients who underwent orthodontic treatment with or without extractions in the DFO unit of the Rabat CCDT (Center for dental consultation and treatment). Patients with prostheses or WSL before the beginning of the study were excluded. Digital start- and end-of-treatment photos for each patient were compared by a single operator looking for the appearance of WSL on the vestibular surfaces of the incisors, canines, premolars and first molars. WSL were classed according to three degrees of severity: slight, severe and cavitation. Data were processed using SPSS 13.0 software. RESULTS: The results of the study showed that the prevalence of WSL in the sample was 66.7%, with a highly significant predominance of localization in the premolar/molar segment and in patients with poor oral hygiene. CONCLUSION: Poor oral and dental hygiene was identified as the most important risk factor for the development of white spots during multibracket orthodontic treatment.