Effects of orthopedic treatment (distraction splint) on dentofacial deformities in patients with juvenile idiopathic arthritis.

BACKGROUND: Juvenile idiopathic arthritis (JIA) frequently affects the temporomandibular joint (TMJ), which can alter mandibular growth and development and result in dentofacial deformities. OBJECTIVE: To assess the outcomes of orthopedic treatment with distraction splint (DS) in patients with JIA-related dentofacial deformity. METHODS: The retrospective study involved 30 patients with JIA and unilateral TMJ involvement, another study group of 20 patients with JIA and bilateral TMJ involvement, and a control group of 18 non-JIA orthodontic patients with Class II and III malocclusions. The inclusion criteria were DS treatment and cone-beam computed tomography (CBCT) scans before (T0) and 2 years after treatment (T1). Dentofacial morphology and deformity were evaluated based on a validated three-dimensional CBCT-based morphometric analysis. Intergroup differences in outcome measures were compared at T0 and T1, and intragroup changes between T0 and T1 were assessed using the Kruskal-Wallis test. RESULTS: Initial evaluations at T0 revealed significant differences between the unilateral and bilateral JIA groups and the control group for three out of eight dentofacial deformity variables: inter-side difference in total posterior mandibular height, mandibular axial angle, and posterior/anterior face height (ratio). At follow-up (T1), significant inter-group differences were only observed in total posterior mandibular height indicating that intergroup differences were less pronounced after splint treatment. Assessing inter-group changes between T0 and T1 showed that all parameters remained constant except posterior/anterior face height ratio, which significantly decreased between T0 and T1. CONCLUSIONS: The findings demonstrate the potential of DS treatment for patients with JIA and unilateral or bilateral TMJ involvement to generally support normal dentofacial growth or at least limit further deterioration of dentofacial deformities.

Initial radiological signs of dentofacial deformity in juvenile idiopathic arthritis.

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in childhood and the temporomandibular joint (TMJ) is often involved. TMJ arthritis in growing individuals can cause deformation of facial skeleton (dentofacial deformity) and TMJ components (TMJ deformity). Treatment outcome hinges on early initiation of anti-inflammatory treatment and orthopaedic treatment with dental splints. The aim of the present study was to characterize the radiological signs of dentofacial deformity in patients with a JIA-induced need for orthopaedic treatment. We retrospectively studied 96 patients with JIA and 20 non-JIA controls to identify the initial radiological signs of JIA-induced dentofacial deformity leading to initiation of orthopaedic treatment. We found that initial radiological signs of dentofacial deformities were subtle and characterized by minor mandibular asymmetry and occlusal plane steepening. Radiological findings of TMJ deformity associated with initial dentofacial deformity were frequent and characterized by condylar articular surface flattening (OR 8.42), condylar subcortical cyst (OR 5.94), condylar surface erosion (OR 5.38) and condylar deviation in form (OR 25.39). Radiological signs of TMJ deformity were also documented in TMJs considered "healthy" during initial clinical and radiological examination. This study presents new knowledge of importance for early diagnosis of dentofacial deformity in JIA. Early diagnosis of dentofacial deformity is important as treatment outcome is greatly influenced by timely initiation.

Características de la posición craneocervical con diferentes oclusiones en pacientes en desarrollo. Relación craneocervical y oclusión / Craniocervical position characteristics in regards with different occlusions in developing patients. Craniocervical relationship and occlusion

En la actualidad la relación entre oclusión y posturología despierta un gran interés científico, sobre todo de cara a la instauración de un tratamiento multidisciplinar. Sin embargo, la diversidad de estudios se refiere sobre todo a la población adulta y no hay un consenso común entre las diferentes investigaciones. En base a ello nos planteamos como objetivo estudiar la posición craneocervical en diferentes oclusiones en población en desarrollo. Mediante un diseño de carácter transversal fueron seleccionados 64 pacientes pediátricos con historia clínica completa y radiografías laterales de cráneo de calidad. Las variables analizadas mediante el software de ImageJ® y Nemoceph® fueron FP-MP, ángulo ANB, OPT-SN, CVT-SN y Ad1-Ba. El análisis estadístico descriptivo y comparativo se llevó a cabo mediante el programa programa IBM SPSS® hallan-do posteriormente la fiabilidad intraexaminador. Los valores p obtenidos para cada una de las variables fueron 0,846 para FP-MP, 0,008 para el ángulo ANB, 0,155 para OPT-SN, 0,415 para CVT-SN y 0,221 para Ad1-Ba. Por todo ello, creemos que la posición craneofacial en las diferentes oclusiones podría estar determinada por el hecho de que el desarrollo todavía no ha finalizado

Currently, the relationship between occlusion and posture arouses great scientific interest, especially during the establishment of a multidisciplinary treatment. However, the diversity of studies refers mostly to the adult population and there is no common agreement among the different investigations. Based on this, we aimed to study the craniocervical position in different occlusions in the developing pediatric population. Through a cross-sectional design, 64 pediatric patients with complete clinical history and high-quality lateral skull radiographs were selected. The variables analyzed by ImageJ® and Nemoceph® software's were FP-MP, ANB angle, OPT-SN, CVT-SN and Ad1-Ba. Descriptive and comparative statistical analysis was carried out with IBM SPSS Statistics® software, subsequently finding intra-examiner agreement. P-values obtained for each of these variables were 0.846 for FP-MP, 0.008 for ANB angle, 0.155 for OPT-SN, 0.415 for CVT-SN, and 0.221 for CVT-SN. Based on these results, we believe that the craniofacial position in the different occlusions could be determined by the fact that the development has not yet been completed

Condyle modeling stability, craniofacial asymmetry and ACTN3 genotypes: Contribution to TMD prevalence in a cohort of dentofacial deformities.

Craniofacial asymmetry, mandibular condylar modeling and temporomandibular joint disorders are common comorbidities of skeletally disproportionate malocclusions, but etiology of occurrence together is poorly understood. We compared asymmetry, condyle modeling stability and temporomandibular health in a cohort of 128 patients having orthodontics and orthognathic surgery to correct dentofacial deformity malocclusions. We also compared ACTN3 and ENPP1 genotypes for association to clinical conditions. Pre-surgical posterior-anterior cephalometric and panometric radiographic analyses; jaw pain and function questionnaire and clinical examination of TMD; and SNP-genotype analysis from saliva samples were compared to assess interrelationships. Almost half had asymmetries in need of surgical correction, which could be subdivided into four distinct morphological patterns. Asymmetric condyle modeling between sides was significantly greater in craniofacial asymmetry, but most commonly had an unanticipated pattern. Often, longer or larger condyles occurred on the shorter mandibular ramus side. Subjects with longer ramus but dimensionally smaller condyles were more likely to have self-reported TMD symptoms (p = 0.023) and significantly greater clinical diagnosis of TMD (p = 0 .000001), with masticatory myalgia most prominent. Genotyping found two significant genotype associations for ACTN3 rs1671064 (Q523R missense) p = 0.02; rs678397 (intronic SNP) p = 0.04 and one significant allele association rs1815739 (R577X nonsense) p = 0.00. Skeletal asymmetry, unusual condyle modeling and TMD are common and interrelated components of many dentofacial deformities. Imbalanced musculoskeletal functional adaptations and genetic or epigenetic influences contribute to the etiology, and require further investigation.

Evaluation of dentofacial asymmetry caused by odontomas using panoramic radiographs.

AIMS: To evaluate the presence of dentofacial asymmetry in patients with odontoma by panoramic radiography. METHODS: Panoramic images with odontoma were selected among all panoramic radiographs (3058 patients). Maxillary odontoma was detected in 27 patients while mandibular odontoma was detected in 25 patients. In addition, 30 patients with similar age and gender characteristics were selected as the control group. Skeletal angular, skeletal linear and dental measurements were performed on panoramic radiographs. The odontoma region and the opposite side of the odontoma of the individuals were examined. The dentofacial asymmetry of the odontoma groups was compared with the control group. Paired t-test was used to determine dentofacial asymmetry on the right and left side of the patients with odontoma. The ANOVA test was used for testing the differences among groups. RESULTS: As a result of study, no significant difference was found between the region of the odontoma and the symmetrical region in the maxilla and mandibula (P > 0.05). In the control group, a statistically significant difference was found in the angle between the mandibular canal and the mental foramen, lower incisor size, PFH/CutCat(°), and Co-Mc-Me(°) measurements (P < 0.05). In the maxillary and mandibular odontoma groups, a statistically significant difference was found in the angle between the mandibular canal and the menton, CH (mm), RH (mm), and CrH (mm) in the comparison of the odontoma and the control group (P < 0.05). CONCLUSIONS: No difference was found between the right and left sides of the jaws related with the asymmetry of the maxilla and mandible.

Short Face Dentofacial Deformities: Changes in Social Perceptions, Facial Esthetics, and Occlusion After Bimaxillary and Chin Orthognathic Correction.

The purpose of this study was to document changes in social perceptions and facial esthetics, and document occlusion outcomes in a series of short face (SF) dentofacial deformity (DFD) subjects. The investigators hypothesized that subjects would achieve positive change in social perceptions and facial esthetics, and maintain a long-term corrected occlusion after undergoing bimaxillary and chin osteotomies.A retrospective cohort study was implemented. Photographic records and occlusion parameters were studied preoperatively and >2 years after surgery. The first outcome variable was social perceptions of SF subjects, judged by laypersons. The second outcome variable was facial esthetics, judged by professionals. The third outcome variable was occlusion maintained long-term.Fifteen subjects met inclusion criteria. Mean age at operation was 33 years. Consistent facial contour deformities at presentation included deficient maxillary dental show and downturned oral commissures. As a group, there was improvement (P < 0.05) in 11 of 12 social perceptions, judged by laypersons, all subjects achieved correction of the facial esthetic parameters studied by professionals, and all subjects maintained a favorable occlusion long-term.In SF DFD subjects, bimaxillary and chin surgery proved effective to improve social perceptions, to correct facial contour deformities, and in achieving a long-term corrected occlusion.

Simultaneous Surgical Correction of Skeletal Class III Dentofacial Deformity During Acute Management of Facial Fractures: Patient Selection and Surgical Technique.

BACKGROUND: Mandibular prognathism is a common dentofacial deformity in Asia. Treatment of such condition may vary from orthodontic camouflage to surgical orthodontics with orthognathic surgery depending on the severity of the condition. Because of the prominent position of the mandible, fractures involving different locations of the mandible commonly occur in maxillofacial trauma. Anatomical reduction of maxillofacial fractures and restoration of the pretraumatic occlusion are the primary goals of acute management of facial fractures. In patients with dentofacial deformity, simultaneous surgical correction of their malocclusion and improvement of their facial aesthetics while providing open treatment to the maxillofacial fractures are rarely reported in the literature. PATIENTS AND METHODS: We reported 3 cases with combined open reduction and internal fixation and surgery-first orthognathic surgery principles to correct class III malocclusion with mandibular prognathism during acute management of maxillofacial fractures. Computer-assisted surgical simulation was used in surgical planning and fabrication of surgical splint. RESULTS: Two patients underwent mandibular osteotomies in addition to open reduction and internal fixation of maxillofacial fractures. One patient had both maxillary and mandibular osteotomies during facial fracture repair. Class I occlusion with satisfactory facial profile was achieved in all 3 cases. CONCLUSIONS: Careful patient selection with presurgical planning using computer-assisted surgical simulation is essential in achieving successful outcomes in correcting dentofacial deformities while managing maxillofacial fractures. This combined technique is a viable option in the surgical management of facial fractures in patients with dentofacial deformities.

Staged therapeutic approach for rehabilitation of severe asymmetric Class II dentofacial deformity secondary to long standing unilateral temporomandibular joint ankylosis.

Despite being one of the most pervasive debilitating skeletal problems in the craniofacial region, surgical-orthodontic management of long-standing asymmetric Class II dentofacial deformities is often a unique challenge posed to the clinicians. This case report describes the encouraging results of systematically sequenced and staged therapeutic approach adopted for successful rehabilitation of an adult patient with asymmetric Class II dentofacial deformity with mandibular micrognathia secondary to unilateral TMJ ankylosis. Concurrent gap arthroplasty and bilateral distraction of mandibular body were performed during the first operation for functional restoration of mandibular movements and correction of mandibular micrognathia and associated asymmetry. After 13 months of post-distraction orthodontic treatment, Le Fort I osteotomy for inferior repositioning and sagittal advancement of maxilla was performed during the second operation, in conjunction with adjunctive alloplastic reconstruction of inferior border of mandible for optimization of facial aesthetics. Postsurgical orthodontic detailing facilitated achievement of stable, balanced interdigitation. The total active treatment period was 29 months. After treatment, both the skeletal disharmony and the functional stability were significantly improved with establishment of functional occlusion. The morphological and functionally acceptable results were reasonably well-maintained during three-year follow-up. The merits of mandibular osteodistraction vs. conventional mandibular orthognathic surgery and the potential advantages of staged surgical approach are discussed.

Cambio de imagen facial en base a rinoseptoplastía y cirugía ortognática: resultados preliminares / Facial makeover based in rhinoplasty and orthognathic surgery. preliminary results

RESUMEN Introducción: La cirugía ortognática y la rinoplastia son procedimientos consolidados con altas tasas de éxito. La sinergia entre ambos procedimientos ha sido presentada en diferentes investigaciones pero aún no es un procedimiento estándar para pacientes con deformidades faciales. Objetivo: Analizar una serie de casos tratados con cirugía ortognática y rinoplastia y discutir las opciones y fundamentos de la técnica combinada. Material y método: 14 pacientes operados de forma consecutiva fueron incluidos en el estudio. Se identificaron sujetos según el tipo de deformidad facial, el tipo de deformidad nasal y los tipos de cirugías realizadas. El seguimiento mínimo de cada sujeto fue de 12 meses. Resultados: El 50% de los sujetos presentaba deformidad facial de clase III, seguido de deformidades de clase II y I. Las deformidades nasales, de la punta y del puente nasal fueron más prevalentes, siendo el ancho nasal también una deformidad común. En la etapa intraoperatoria, después de realizar la cirugia ortognática, fue necesario realizar un análisis nuevo respecto de la morfologia nasal debido a los cambios que generaba el movimiento maxilar en la condición nasal. Conclusión: La cirugía combinada es sinérgica y viable de ser realizada con bajo número de complicaciones; protocolos y nuevos criterios de análisis son necesarios para obtener mayor predictibilidad en los resultados estéticos.

ABSTRACT Introduction: Orthognathic surgery and rhinoplasty are procedures with high success rate. The synergy between both surgeries has been showed in the past by researches but still they are not standardized procedures for the treatment of patients with facial deformities. Aim: To analyze a case series treated with orthognathic surgery and rinoplasty in the same surgical time, discussing surgical options and techniques in the combined procedure. Material and method: 14 patients were treated consecutively and were included in this research. Subjects were selected by facial deformity, nasal deformity and type of surgery. Minimal follow up was for 12 months to observe results. Results: 50% of subjects showed class III facial deformity, follow by class II and class I facial deformity. In nasal deformities, tip and nasal bridge were more prevalent, being the nasal width a common deformity; in the intraoperative time, after orthognathic surgery, it was necessary to make a new analysis and approach to nasal morphology because the new conditions related to movement of the maxilla. Conclusion: Orthognathic and nasal surgery are good complement and it is possible to do with few complications; surgical protocol and criteria for the analysis are necessaries to obtain more predictability in the esthetic results.

Does facial appearance of dentofacial deformity influence the need for orthognathic surgery: The Malaysian perception.

Aim: This study evaluates perception toward facial appearance in dentofacial deformity and the need for orthognathic surgery among the public with and without dental backgrounds. Materials and Methods: A questionnaire consisting of 12 facial photographs of cases with dentofacial deformity or malocclusion in varying severity was used. A hundred individuals were selected to answer the questionnaire. The perception of facial appearance (FAS), treatment need score (TNS), and knowledge regarding dentofacial deformity were used for the evaluation. Results: Significant differences were found between dental and non-dental when the respondents' knowledge in all the questionnaire items ([Formula: see text].05) was assessed. However, no significant difference was found in the mean of FAS and TNS in all the presented cases (normal, borderline, severe). Pearson correlation between perceived FAS and TNS was statistically negative for severe and normal cases, whereby a decrease in FAS for severe cases showed an increase in TNS, and an increase in FAS for normal cases showed a decrease in TNS. Conclusion: Respondents with dental background had sound knowledge of dentofacial deformity. A poorly attractive respondent with dentofacial deformity showed a greater need for orthognathic surgery.

Digital platform for planning facial asymmetry orthodontic-surgical treatment preparation.

Dentofacial deformities usually are surgically treated, and 3D virtual planning has been used to favor accurate outcomes. Cases reported in the present article show that orthognathic surgery carried out to correct facial asymmetries does not comprise only one treatment protocol. 3D virtual planning might be used for surgical planning, but it should also be used to diagnose the deformity, thus allowing for an analysis of the best-recommended possibilities for the orthodontic preparation that suits each individual case.

Digital platform for planning facial asymmetry orthodontic-surgical treatment preparation

ABSTRACT Dentofacial deformities usually are surgically treated, and 3D virtual planning has been used to favor accurate outcomes. Cases reported in the present article show that orthognathic surgery carried out to correct facial asymmetries does not comprise only one treatment protocol. 3D virtual planning might be used for surgical planning, but it should also be used to diagnose the deformity, thus allowing for an analysis of the best-recommended possibilities for the orthodontic preparation that suits each individual case.

RESUMO As deformidades dentofaciais são, geralmente, tratadas de forma cirúrgica, e o planejamento virtual 3D tem sido utilizado para aumentar a precisão dos resultados. Os casos exemplificados no presente artigo mostram que a cirurgia ortognática para correção das assimetrias faciais não apresenta um único protocolo de tratamento. O planejamento virtual 3D pode ser adotado para planejar a cirurgia, mas também deve ser utilizado na fase de diagnóstico da deformidade, assim permitindo uma análise das possibilidades mais indicadas para o preparo ortodôntico mais adequado em cada caso.

Identification of 'Point A' as the prevalent source of error in cephalometric analysis of lateral radiographs.

Deviations in measuring dentofacial components in a lateral X-ray represent a major hurdle in the subsequent treatment of dysgnathic patients. In a retrospective study, we investigated the most prevalent source of error in the following commonly used cephalometric measurements: the angles Sella-Nasion-Point A (SNA), Sella-Nasion-Point B (SNB) and Point A-Nasion-Point B (ANB); the Wits appraisal; the anteroposterior dysplasia indicator (APDI); and the overbite depth indicator (ODI). Preoperative lateral radiographic images of patients with dentofacial deformities were collected and the landmarks digitally traced by three independent raters. Cephalometric analysis was automatically performed based on 1116 tracings. Error analysis identified the x-coordinate of Point A as the prevalent source of error in all investigated measurements, except SNB, in which it is not incorporated. In SNB, the y-coordinate of Nasion predominated error variance. SNB showed lowest inter-rater variation. In addition, our observations confirmed previous studies showing that landmark identification variance follows characteristic error envelopes in the highest number of tracings analysed up to now. Variance orthogonal to defining planes was of relevance, while variance parallel to planes was not. Taking these findings into account, orthognathic surgeons as well as orthodontists would be able to perform cephalometry more accurately and accomplish better therapeutic results.

Assessment of dentofacial growth deviation in juvenile idiopathic arthritis: Reliability and validity of three-dimensional morphometric measures.

INTRODUCTION: Patients with juvenile idiopathic arthritis (JIA) and involvement of the temporomandibular joint (TMJ) often experience abnormal facial growth. Three-dimensional (3D) assessment of dentofacial growth deviation has become more common with advancement and commercialization of imaging technologies. However, no standardized guidelines exist for interpretation of 3D imaging in patients with JIA. The aim of this study was to propose and validate morphometric measures for the 3D radiographic assessment of dentofacial growth deviation in patients with JIA to enhance: 1) Description of dentofacial growth deviation; 2) Treatment planning; 3) Longitudinal follow-up. METHODS: The study was conducted in a standardized sequential-phased approach involving: 1) Preliminary decision-making; 2) Item generation; 3) Test of content-validity; 4) Test of reliability; 5) Test of construct validity; 6) Establishment of final recommendations. RESULTS: Twenty-one morphometric measures were evaluated. Based on results of reliability and validity-testing including subjects with JIA (n = 70) and non-JIA controls (n = 19), seven measures received a "high recommendation" score. Those measures were associated with posterior mandibular height, occlusal cant, mandibular asymmetry, mandibular inclination, and anterior/posterior lower face height. Nine other measures were "moderately recommended" and five received a "somewhat recommendation" score. CONCLUSION: Seven morphometric measures were considered very useful in the 3D assessment of growth deviation in patients with TMJ disease associated with JIA. These variables can be used to standardize the description of dentofacial deformities and to plan corrective interventions.

Accuracy of Orthognathic Surgical Outcomes Using 2- and 3-Dimensional Landmarks-The Case for Apples and Oranges?

PURPOSE: To verify predicted versus obtained surgical movements in 2-dimensional (2D) and 3-dimensional (3D) measurements and compare the equivalence between these methods. MATERIALS AND METHODS: A retrospective observational study of bimaxillary orthognathic surgeries was performed. Postoperative cone-beam computed tomographic (CBCT) scans were superimposed on preoperative scans and a lateral cephalometric radiograph was generated from each CBCT scan. After identification of the sella, nasion, and upper central incisor tip landmarks on 2D and 3D images, actual and planned movements were compared by cephalometric measurements. One-sample t test was used to statistically evaluate results, with expected mean discrepancy values ranging from 0 to 2 mm. Equivalence of 2D and 3D values was compared using paired t test. RESULTS: The final sample of 46 cases showed by 2D cephalometry that differences between actual and planned movements in the horizontal axis were statistically relevant for expected means of 0, 0.5, and 2 mm without relevance for expected means of 1 and 1.5 mm; vertical movements were statistically relevant for expected means of 0 and 0.5 mm without relevance for expected means of 1, 1.5, and 2 mm. For 3D cephalometry in the horizontal axis, there were statistically relevant differences for expected means of 0, 1.5, and 2 mm without relevance for expected means of 0.5 and 1 mm; vertical movements showed statistically relevant differences for expected means of 0, 0.5, 1.5 and 2 mm without relevance for the expected mean of 1 mm. Comparison of 2D and 3D values displayed statistical differences for the horizontal and vertical axes. CONCLUSIONS: Comparison of 2D and 3D surgical outcome assessments should be performed with caution because there seems to be a difference in acceptable levels of accuracy between these 2 methods of evaluation. Moreover, 3D accuracy studies should no longer rely on a 2-mm level of discrepancy but on a 1-mm level.

Dental anomalies in pediatric patients with familial adenomatous polyposis.

Familial adenomatous polyposis patients often present with non-malignant extra-intestinal manifestations which include dental anomalies that may be evident prior to the appearance of the colonic adenomas. The aims of this study were to describe the prevalence and type of dental anomalies and the relationships between gene mutations and dental anomalies in these patients. Twenty-two pediatric familial adenomatous polyposis patients and 46 controls, who were age and gender matched participated. Familial adenomatous polyposis patient's had a dental examination with panoramic radiograph and medical record review for age at diagnosis, the presence of the adenomatous polyposis coli gene mutation, and determination of other extra-intestinal manifestations on the body. The control group was identified from a retrospective chart review and selected if there was a current panoramic radiograph. The only significant difference between familial adenomatous polyposis patients and controls were the presence of jaw osteomas and sclerosis (p = .0001). Patients with a mutation in, or upstream of codon 1309 had a higher frequency of osteomas (77.8%) and jaw-bone sclerosis (44.4%), and 77% of these had at least one dental anomaly. This preliminary study showed an association between a genetic variant at, or upstream of codon 1309, and radiographic dental anomalies.

Radiographic evaluation of condylar positioning in patients undergoing orthognathic surgery.

OBJECTIVE: The aim of this study was to evaluate alterations in condylar positioning through submentovertex projection (Hirtz Radiographic Technique) in patients who underwent orthognathic surgery for maxillary advancement and mandibular setback with stable internal fixation. METHODS: A prospective longitudinal clinical study of 40 surgical patients presenting dentofacial deformity admitted in the Oral and Maxillofacial Surgery Department of Federal University of Paraná (UFPR) in the period between March 2013 and December 2015. We performed two submentovertex digital radiographs, one 7 days before surgery and the other one 30 days after the procedure. Cephalometric tracings were made using Radiocef® Studio 2 Software and measured the intercondylar and condylar angles (right and left). RESULTS: There was a decrease in the intercondylar angle (p < 0.001) and an increase in condylar angles both the right and the left side (p < 0.001) when compared with the pre and postoperative period. There was a larger increase in condylar angle on the right side in males (p = 0.007). CONCLUSION: There is a tendency of decreasing of the intercondylar angle after orthognathic surgery, regardless of the alteration in the condylar angles, creating a new position of the condyle in the glenoid fossa. Patients with asymmetry may present greater alterations in the positioning of the opposite condylar to the deviation of the mandibular midline.

Three-Dimensional Accuracy of Facial Scan for Facial Deformities in Clinics: A New Evaluation Method for Facial Scanner Accuracy.

In this study, the practical accuracy (PA) of optical facial scanners for facial deformity patients in oral clinic was evaluated. Ten patients with a variety of facial deformities from oral clinical were included in the study. For each patient, a three-dimensional (3D) face model was acquired, via a high-accuracy industrial "line-laser" scanner (Faro), as the reference model and two test models were obtained, via a "stereophotography" (3dMD) and a "structured light" facial scanner (FaceScan) separately. Registration based on the iterative closest point (ICP) algorithm was executed to overlap the test models to reference models, and "3D error" as a new measurement indicator calculated by reverse engineering software (Geomagic Studio) was used to evaluate the 3D global and partial (upper, middle, and lower parts of face) PA of each facial scanner. The respective 3D accuracy of stereophotography and structured light facial scanners obtained for facial deformities was 0.58±0.11 mm and 0.57±0.07 mm. The 3D accuracy of different facial partitions was inconsistent; the middle face had the best performance. Although the PA of two facial scanners was lower than their nominal accuracy (NA), they all met the requirement for oral clinic use.

Comparative Evaluation of Condylar Volume Between Patients With Unilateral Condylar Hyperplasia and Class III Dentofacial Deformity.

PURPOSE: To compare the condylar volume of patients with unilateral condylar hyperplasia (UCH) with that of patients with a Class III skeletal relation. MATERIALS AND METHODS: Twenty cone-beam computed tomograms of patients were analyzed. Images were divided into 2 groups: 10 from patients with transverse asymmetry of the face and 10 from patients with a Class III facial deformity. Patients' ages ranged from 15 to 30 years. Volumetric data were reconstructed using Dolphin 3D software (Dolphin Imaging & Management Solutions, Chatsworth, CA). This software measured the condylar volume above the deepest point of the sigmoid notch, the lower arch midline deviation, and the overjet. RESULTS: The condyle with hyperplasia exhibited the largest volume (1.97 ± 0.52 cm3) and a statistically significant difference compared with the contralateral condyle (χ2 = 14.30; P < .01). The Class III condyle exhibited relative symmetry of volume between the left and right sides. These condyles exhibited a larger volume compared with the non-hyperplastic condyles in the UCH group, with a statistically significant difference (χ2 = 6.22; P = .013; χ2 = 5.50; P = .019). CONCLUSIONS: Hyperplastic condyles were similar in volume to the condyles of patients with mandibular prognathism, suggesting that patients with a Class III skeletal relation could exhibit bilateral condylar hyperplasia.