Craniofacial Orthodontic Experience in CODA-Accredited Orthodontic Residency Programs.

To evaluate orthodontic care for patients with craniofacial anomalies (CFA) by identifying orthodontic residents' preparedness to treat certain conditions and willingness to receive more training in CFA.A 12-question survey was sent through the American Association of Orthodontics (AAO) organization to orthodontic residents. Questions were primarily designed to obtain information on the frequency with which they dealt with patients with CFA in their training, specific craniofacial conditions that orthodontic residents feel comfortable treating.A total of 150 participants out of 1066 responded. Of the 150 responses, 35% were first-year residents, 43% second year, and 22% were third-year residents. Thirty nine percent of residents saw 3 or more CFA patients during their residency followed by 24% that saw no patients with CFA. Forty five percent reported that 1 to 3 hours of lecture time was devoted to CFA per month. Sixty percent felt their training in CFA was not sufficient to feel comfortable treating these patients in practice. Specifically, 62% felt comfortable treating Down syndrome, 84% unilateral cleft lip and/or palate, and 64% bilateral cleft lip and/or palate, while the majority did not feel comfortable treating Pierre Robin sequence (68%), Cleidocranial dysplasia (65%), Crouzon syndrome (75%), Pfeiffer syndrome (80%), Treacher Collins syndrome (76%), Apert syndrome (76%), CHARGE syndrome (84%), and DiGeorge sequence (84%). Seventy eight percent of residents reported that they would like more training in treating craniofacial.Orthodontic residents did not feel comfortable treating patients with CFA. Majority of the residents felt that they would like to learn more about CFA.

A 3-Dimensional Evaluation of the Effects of Unilateral Vertical Mandibular Distraction Osteogenesis on Airway Volume Among Patients With Hemifacial Microsomia.

OBJECTIVE: The aim of this study was to evaluate the volumetric airway changes using three-dimensional images following unilateral vertical mandibular distraction osteogenesis (uVMD) among patients with hemifacial microsomia (HFM). DESIGN: This retrospective study analyzed cone-beam computed tomography (CBCT) scans of patients with HFM at three different timepoints; pretreatment (T0), posttreatment (T1), and at least 6 months post-distraction (T2). The individuals underwent uVMD between December 2018-Januaray 2021. The nasopharyngeal (NP) volume, oropharyngeal (OP) volume, and the area of maximum constriction (MC) were measured. Wilcoxon signed-rank test was used to compare the airway volumes between T0-T1, T1-T2, and T0-T2. RESULTS: Five patients met the inclusion criteria (mean age = 10.4 years; 1 female, 4 males). Intraclass correlation analysis showed excellent interrater reliability (r > .86, P < .001). Posttreatment, the OP airway volume exhibited a significant mean increase of 56% (P = .043) from T0 to T1, but decreased from T1-T2 by 13%. Likewise, the total airway volume presented with a significant mean increase of 48% between T0-T1 (P = .044), and a decrease of 7% from T1-T2. The changes in the NP airway volume and area of MC were not statistically significant (P > .05), but an increase in the mean values were observed. CONCLUSION: Surgical intervention with uVMD may significantly increase the OP airway volume and the total airway volume among patients with HFM immediately after distraction. However, the statistical significance diminished after six months post-consolidation, but the mean percent change may remain of clinical significance. The NP volume did not seem to show significant changes in response to uVMD.

Estimating Craniofacial Growth Cessation: Comparison of Asymptote- and Rate-Based Methods.

OBJECTIVE: To identify differences between asymptote- and rate-based methods for estimating age and size at growth cessation in linear craniofacial measurements. DESIGN: This is a retrospective, longitudinal study. Five linear measurements were collected from lateral cephalograms as part of the Craniofacial Growth Consortium Study (CGCS). Four estimates of growth cessation, including 2 asymptote- (GCasym, GCerr) and 2 rate-based (GCabs, GC10%) methods, from double logistic models of craniofacial growth were compared. PARTICIPANTS: Cephalometric data from participants in 6 historic longitudinal growth studies were included in the CGCS. At least 1749 individuals (870 females, 879 males), unaffected by craniofacial anomalies, were included in all analyses. Individuals were represented by a median of 11 images between 2.5 and 31.3 years of age. RESULTS: GCasym consistently occurred before GCerr and GCabs consistently occurred before GC10% within the rate-based approaches. The ordering of the asymptote-based methods compared to the rate-based methods was not consistent across measurements or between males and females. Across the 5 measurements, age at growth cessation ranged from 13.56 (females, nasion-basion, GCasym) to 24.39 (males, sella-gonion, GCerr). CONCLUSIONS: Adolescent growth cessation is an important milestone for treatment planning. Based on our findings, we recommend careful consideration of specific definitions of growth cessation in both clinical and research settings since the most appropriate estimation method may differ according to patients' needs. The different methods presented here provide useful estimates of growth cessation that can be applied to raw data and to a variety of statistical models of craniofacial growth.

The Relationship Between Dental Agenesis and Maxillary Hypoplasia in Patients With Cleft Lip and Palate.

ABSTRACT: Both dental agenesis and maxillary growth restriction are well-recognized sequelae in patients with unilateral cleft lip and palate, but their etiology remains controversial. The aim of this study was to evaluate the relationship between hypodontia and maxillary volume. A retrospective review of patients age 6 to 9 with Veau III (unilateral) cleft palate who underwent Cone Beam Computer Tomography in preparation for alveolar bone grafting at 2 major Children's Hospitals between 2010 and 2016 was conducted and serial panoramic radiographs were reviewed. Thirty-eight patients were identified that met inclusion criteria and had adequate imaging. Group 1 ("poor growers") consisted of the bottom 50% of Sella-Nasion-A point minus Sella-Nasion-B point (ANB) angles and Group 2 ("good growers") consisted of the top 50% of ANB angles. Group 1 had a significantly higher mean number of missing teeth (1.58 ±â€Š0.28 missing teeth) compared to Group 2 (0.74 ±â€Š0.23 missing teeth), and significantly lower maxillary volume (12.88 ±â€Š0.61 cm3 versus 15.24 ±â€Š0.88 cm3, respectively). The severity of maxillary hypoplasia in cleft patients increases with increased dental agenesis. These data indicate that intrinsic factors play a significant role in maxillary growth restriction in cleft patients, independent of the sequelae of surgical intervention.

A Qualitative Assessment of Bone Mineral Density in Individuals With Hemifacial Microsomia: A Cone-Beam Computed Tomography Study.

OBJECTIVE: The purpose of this study is to utilize cone-beam computed tomography (CBCT) to compare the bone mineral density (BMD) on the affected versus nonaffected side, among individuals with hemifacial microsomia (HFM). METHODS: This retrospective study included 9 patients with HFM. Pretreatment CBCT volumes were imported into Invivo5 software, which was used to measure BMD through Hounsfield units (HU) in 3 regions of the mandible; inferior to the lower lateral incisors, inferior to the first molar and at the ramus inferior to the sigmoid notch. Each region was measured at the buccal cortical bone, lingual cortical bone, and cancellous bone. The densities on the right and left sides were compared by Wilcoxon signed-rank test. RESULTS: Overall, the BMD on the affected side tended to show slightly lower values when compared with the nonaffected side. Differences ranged from 14 HU at the lingual cortical plate of the first molar region to 234 HU at the buccal cortical plate of the ramus region. Differences were only statistically significant at the ramus region for the buccal (P = .002) and lingual (P < .001) cortical plates and at the lower incisor region at the buccal cortical plate (P = .016) and cancellous bone (P = .044). The differences, however, did not seem to be clinically significant. CONCLUSIONS: The current study shows that the quality of bone on the affected side may be slightly reduced but did not seem to be clinically significant. This should be accounted for during surgical and orthodontic planning for patients with HFM.

When convenience trumps quality of care: A population-based survey on direct to consumer orthodontics.

INTRODUCTION: Since the introduction of direct to consumer orthodontic (DTCO) products in the last decade, these products have been increasing in popularity among orthodontic patients. The purpose of the current article was to assess the populations' perception of DTCOs and to examine various factors that may influence their decision in choosing treatment with DTCO products. METHODS: A cross-sectional population-based survey was conducted in the United States. The 35-question survey was disseminated through Amazon Mechanical Turk (Amazon.com, Inc, Seattle, Wash), and participants were asked questions about their demographics, their perceptions of DTCOs, orthodontists, and factors that may influence their decision should they decide to pursue orthodontic treatment. Pearson's correlations were conducted to assess the association between various factors and the participants' likelihood to choose DTCO products. RESULTS: A total of 1441 subjects participated in the study. More than 83% of the participants have considered pursuing orthodontic treatment to some extent. Twenty-three percent reported that they would highly likely choose DTCO products. The majority of participants reported convenience to be the greatest benefit of DTCOs, followed by cost. The majority of responses seemed to favor DTCOs. Forty-seven percent reported that the coronavirus disease 2019 pandemic did not affect their preference, whereas 26.6% reported to be more likely to pursue DTCOs because of the pandemic. CONCLUSIONS: The majority of participants seemed to perceive DTCOs as a viable alternative for seeking orthodontic care. Although participants had concerns about the coronavirus disease 2019 pandemic, results showed that the pandemic might not significantly affect the preferences. Orthodontists and their constituent organizations may consider more robust awareness and advocacy campaigns to educate the population about orthodontic treatment and the benefits of pursuing treatment with a trained orthodontist.

Bias in a blink: Shedding light on implicit attitudes toward patients with a cleft lip.

INTRODUCTION: Previous studies have shown that patients with cleft lip and/or palate may be stigmatized in society. The objective of this study was to use an implicit association test to evaluate the subconscious biases of non-health care providers and orthodontists against patients with a repaired cleft lip (CL). METHODS: Respondents participated in an implicit association test. Pictures of patients with CL and controls were shown to participants, along with terms representing positive and negative attributes. Participants were prompted to match pictures to the attributes. The software algorithm detected whether the participants were more likely to associate CL with positive or negative terms than controls. Demographic information was collected to measure the association between some sociodemographic factors and implicit biases. RESULTS: Of 130 valid participants, 52 were orthodontists and 78 were non-health care providers. The entire sample displayed a significant implicit bias against CL (P <0.001). Overall, orthodontists tended to exhibit slightly higher levels of implicit biases against CL than non-health care providers, but the difference was not significant when controlling for sociodemographic factors (P = 0.34). Females showed significantly lower implicit biases against CL than males (P = 0.046). Spearman correlations showed that older people and those who reported a more conservative political affiliation tended to show slightly higher levels of implicit biases against CL (P <0.007). CONCLUSIONS: Orthodontists and non-health care providers showed moderate but significant levels of implicit biases against patients with clefts. Males, older age groups, and patients with a more conservative political affiliation tended to exhibit slightly higher levels of biases than females, younger people, and those with a more liberal political affiliation.

Geometric morphometric analysis of growth patterns among facial types.

INTRODUCTION: Extreme patterns of vertical facial divergence are of great importance to clinicians because of their association with dental malocclusion and functional problems of the orofacial complex. Understanding the growth patterns associated with vertical facial divergence is critical for clinicians to provide optimal treatment. This study evaluates and compares growth patterns from childhood to adulthood among 3 classifications of vertical facial divergence using longitudinal, lateral cephalograms from the Craniofacial Growth Consortium Study. METHODS: Participants (183 females, 188 males) were classified into 1 of 3 facial types on the basis of their adult mandibular plane angle (MPA): hyperdivergent (MPA >39°; n = 40), normodivergent (28° ≤ MPA ≤ 39°; n = 216), and hypodivergent (MPA <28°; n = 115). Each individual had 5 cephalograms between ages 6 and 20 years. A set of 36 cephalometric landmarks were digitized on each cephalogram. Landmark configurations were superimposed to align 5 homologous landmarks of the anterior cranial base and scaled to unit centroid size. Growth trajectories were calculated using multivariate regression for each facial type and sex combination. RESULTS: Divergent growth trajectories were identified among facial types, finding more similarities in normodivergent and hypodivergent growth patterns than either share with the hyperdivergent group. Through the use of geometric morphometric methods, new patterns of facial growth related to vertical facial divergence were identified. Hyperdivergent growth exhibits a downward rotation of the maxillomandibular complex relative to the anterior cranial base, in addition to the increased relative growth of the lower anterior face. Conversely, normodivergent and hypodivergent groups exhibit stable positioning of the maxilla relative to the anterior cranial base, with the forward rotation of the mandible. Furthermore, the hyperdivergent maxilla and mandible become relatively shorter and posteriorly positioned with age compared with the other groups. CONCLUSIONS: This study demonstrates how hyperdivergent growth, particularly restricted growth and positioning of the maxilla, results in a higher potential risk for Class II malocclusion. Future work will investigate growth patterns within each classification of facial divergence.

Clinical implications of age-related change of the mandibular plane angle.

OBJECTIVE: To identify trajectories of ontogenetic change in the mandibular plane angle (MPA) and to describe the influence of sex and other factors on MPA during growth. SETTING/SAMPLE: The data consisted of 7026 MPA measurements from lateral cephalographs representing longitudinal series from ages 6 to 21 for 728 individuals from the Craniofacial Growth Consortium Study (CGCS). MATERIALS AND METHODS: Facial type was determined from MPA for each assessment, with the assessment closest to age 18 representing the adult facial type. The sample includes 366 males and 362 females, each with between 2 and 15 cephalographs. The mean number of cephalographs per individual is 10. Variation in childhood MPA (earliest assessment between 6 and 9 years of age) and adult MPA (closest assessment to age 18 between 15 and 21 years of age), and change in MPA from childhood to adulthood were compared by sex and adult facial type using ANOVA and post hoc t tests. RESULTS: Mandibular plane angle decreased from childhood to adulthood in 92% of males and 81% of females, yet increased in 36% of males and 50% of females with the hyper-divergent adult facial type. Childhood MPA and overall change in MPA were significantly different by adult facial type. CONCLUSIONS: Adult facial type is associated with differences in childhood MPA and change in MPA during growth. There are multiple ontogenetic pathways by which an individual can achieve a normo-divergent adult facial type, and an individual's childhood MPA does not necessarily correspond to his or her adult facial type.

Comparison of the Pharyngeal Airway Volume Between Patients With Ectodermal Dysplasia and Unaffected Controls: A Cone-Beam Computed Tomography Study.

PURPOSE: Ectodermal dysplasias (EDs) are a diverse set of hereditary conditions in which 2 or more ectodermal structures develop abnormally. The purpose of this study was to use cone-beam computed tomography (CBCT) scans to measure the pharyngeal airway volume and minimum cross-sectional area (MC) among patients with ED and compare them with healthy controls. PATIENTS AND METHODS: The pretreatment CBCT scans of 9 individuals with ED and 61 controls were analyzed. Lateral cephalograms were created from the CBCT volumes and then traced and compared between the 2 groups. Airway volumes were evaluated by Dolphin 3D software (Dolphin Imaging, Chatsworth, CA) to compare the total pharyngeal volume, nasopharyngeal volume, oropharyngeal volume, hypopharyngeal volume, and MC. The mean airway volumes of the 2 groups were compared, and the odds ratio and relative risk of having an MC of less than 100 mm2 in the ED group were calculated. RESULTS: Intraclass correlation analysis showed excellent inter-rater reliability. All cephalometric features of controls were within the norms of patients with ideal skeletal-dental relationships. Patients with ED displayed significantly lower values for SNA (angle between sella-nasion and nasion-A point) (P = .018), ANB (angle between nasion-A point and nasion-B point) (P = .002), L1-MP (angle between long axis of mandibular incisor and gonion-menton plane) (P = .013), and L1-NB (distance between mandibular incisor and perpendicular line between nasion and B point) (P < .001). Although the ED group exhibited slightly smaller airway volumes for all subregions, the differences were not statistically significant for total pharyngeal volume, nasopharyngeal volume, oropharyngeal volume, hypopharyngeal volume, or MC (P > .05). The odds of having an MC of less than 100 mm2 were almost 3 times greater among ED patients, and the relative risk of an MC of less than 100 mm2 among ED patients was double that of controls. CONCLUSIONS: Although the craniofacial structures of individuals with ED are characterized by maxillary and midface deficiency, the airway volumes among affected individuals may not be significantly different from those of unaffected controls. However, patients with ED displayed a higher risk of having an MC of less than 100 mm2, which may be of clinical significance and warrants further investigations with larger samples.

Accuracy of Three-Dimensional Upper Airway Prediction in Orthognathic Patients Using Dolphin Three-Dimensional Software.

BACKGROUND: Orthodontists and surgeons have been looking for more accurate methods to predict surgical outcomes in patients with skeletal discrepancies. METHODS: The sample consisted of 20 patients from the surgical clinic of a graduate orthodontic program who had been treated with Le Fort I maxillary movement, bilateral sagittal split osteotomy, with or without genioplasty. All patients had to have preoperative (T0) and at least 6 months postoperative (T1) cone-beam computed tomographies that were imported to Dolphin 3-dimensional (3D) software. The 3D voxel-based superimposition on the cranial base was performed for T0 and T1 to accurately measure the skeletal surgical movements. A virtual orthognathic surgery was performed on T0 to mimic the actual skeletal osteotomies using the treatment simulation tool in Dolphin 3D. A prediction 3D soft-tissue image (Tp) was generated based on the Dolphin virtual skeletal planning. The upper airway was segmented and exported as stereolithography surface files in both T1 and Tp. The measurements of the 3D volume of the airway were calculated and compared among T1 and Tp by using surface superimposition technique. Mean and standard deviations of upper airway volume were compared and correlated using paired t-test. RESULTS: There was no statistically significant difference between the upper airway volume of T1 and Tp. CONCLUSION: Dolphin 3D delivers accurate airway prediction which is an important step in 3D virtual planning.

Psychosocial Adjustments Among Adolescents With Craniofacial Conditions and the Influence of Social Factors: A Multi-Informant Study.

BACKGROUND: Previous studies have investigated psychosocial adjustments among adolescents with cleft lip and/or palate (CL/P), but our understanding of other craniofacial conditions remains limited. The objective of this study is to compare psychosocial adjustments among 3 groups of adolescents: craniofacial conditions other than cleft lip and/or palate (craniofacial anomaly [CFA]), CL/P, and controls (CON). Our secondary objective is to examine how social factors may predict the adjustments levels. DESIGN: Cross-sectional, multi-informant, controlled survey study. PARTICIPANTS: Aged 11- to 17-year olds. Craniofacial anomaly (n = 49), isolated CL/P (n = 42), and 55 CON. Total = 146. OUTCOME MEASURES: The Strengths and Difficulties Questionnaire (self-report, parent report, and teacher report). RESULTS: All 3 informant groups displayed similar patterns, where CFA reported the highest difficulties, followed by CL/P, while CON scored the lowest. Parent reports demonstrated significant differences among the 3 groups for most subscales and were emphasized for peer problems. Self-reports showed significant differences between CFA and CON for total scores and peer problems, while teacher reports showed significant differences for peer problems only. Craniofacial anomaly displayed the highest frequency of abnormal psychosocial adjustments, followed by CL/P. Experiencing bullying or teasing predicted increased difficulties, while having a good friend predicted decreased difficulties. CONCLUSIONS: Adolescents with CFA, and to a lesser extent CL/P, may be at a higher risk of having psychosocial problems. Peer problems may constitute the biggest challenge that CFA and CL/P confront. Social factors, especially being bullied or having a good friend, may predict the psychosocial well-being of adolescents with craniofacial conditions.

A novel method for fabricating nasoalveolar molding appliances for infants with cleft lip and palate using 3-dimensional workflow and clear aligners.

INTRODUCTION: Nasoalveolar molding (NAM) was introduced over 20 years ago as adjunctive therapy for the correction of cleft lip and palate. In the current study, we propose a new approach using a digital workflow and 3-dimensional printing to fabricate clear aligner NAM devices. METHODS: A polyvinyl siloxane (PVS) impression of an infant with a unilateral complete cleft lip and palate (UCLP) is acquired and poured, and the stone model is scanned with an intraoral scanner. The stereolithography file is digitized, and the alveolar segments are digitally segmented and moved to the desired final position. The total distance moved is divided into a sequence of 1-1.5 mm increments, creating a series of digital models. The models are 3-dimensionally printed along with button templates to allow free form positioning of the button on each model. A Vacuform machine (Taglus, Mumbai, India) was used to fabricate a 0.040-in aligner for each stage. RESULTS: We present 1 case that was treated successfully with this approach. Appointments for the NAM adjustments were primarily to monitor progress and counseling with less time spent adjusting the appliance. The appointment length was reduced by over 30 minutes. Benefits of the aligner are improved fit, more precise increments of activation, reduced chairside time, and potentially minimized number of visits. CONCLUSIONS: NAM custom aligners may provide similar benefits to the traditional approach while reducing the burden of care by reducing the number of visits and appointment duration. Further studies with a sample and longitudinal observations are needed to investigate the benefits of the proposed digital approach.

Predicting adult facial type from mandibular landmark data at young ages.

OBJECTIVES: To assess the potential of predicting adult facial types at different stages of mandibular development. SETTING AND SAMPLE POPULATION: A total of 941 participants from the Bolton-Brush, Denver, Fels, Iowa, Michigan and Oregon growth studies with longitudinal lateral cephalograms (total of 7166) between ages 6-21 years. MATERIAL AND METHODS: Each participant was placed into one of three facial types based on mandibular plane angle (MPA) from cephalograms taken closest to 18 years of age (range of 15-21 years): hypo-divergent (MPA < 28°), normo-divergent (28°≤ MPA ≤ 39°) and hyper-divergent (MPA > 39°). Cephalograms were categorized into 13 age groups 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 and 18-21. Twenty-three two-dimensional anatomical landmarks were digitized on the mandible and superimposed using generalized Procrustes analysis, which projects landmarks into a common shape space. Data were analysed within age categories using stepwise discriminant analysis to identify landmarks that distinguish adult facial types and by jackknife cross-validation to test how well young individuals can be reclassified into their adult facial types. RESULTS: Although each category has multiple best discriminating landmarks among adult types, three landmarks were common across nearly all age categories: menton, gonion and articulare. Individuals were correctly classified better than chance, even among the youngest age category. Cross-validation rates improved with age, and hyper- and hypo-divergent groups have better reclassification rates than the normo-divergent group. CONCLUSIONS: The discovery of important indicators of adult facial type in the developing mandible helps improve our capacity to predict adult facial types at a younger age.

Accuracy of Three-Dimensional Soft Tissue Prediction in Orthognathic Cases Using Dolphin Three-Dimensional Software.

INTRODUCTION: Orthodontists and surgeons have been looking for more accurate methods to plan and predict surgical outcomes in patients with skeletal discrepancies. METHODS: The sample consisted of 20 subjects from the surgical clinic of a graduate orthodontic program who had been treated with Le Fort I maxillary movement, bisagittal split osteotomy, with or without genioplasty. All subjects had to have preoperative (T0) and at least 6 months postoperative (T1) cone-beam computed tomographies that were imported to Dolphin three-dimensional (3D) software version 11.9 in digital imaging and communications in medicine format. Three-dimensional voxel-based superimposition on the cranial base was performed for T0 and T1 to accurately measure the skeletal surgical movements. A virtual orthognathic surgery was performed on T0 to mimic the actual skeletal osteotomies using the treatment simulation tool in Dolphin 3D. A prediction 3D soft tissue image (Tp) was generated based on the Dolphin virtual skeletal planning. The differences between Tp and T1 for all patients were measured using linear and angular measurements visualized by surface mapping. RESULTS: Significant differences were found between Tp and T1 in Nasolabial angle, Soft tissue A point, and Subalar area. CONCLUSIONS: The soft tissue prediction accuracy after double jaw surgery using Dolphin 3D is limited in some areas, especially upper lip and base of the nose.

Innovative Surgical Treatment of Severe Cherubism.

BACKGROUND: Cherubism is an autosomal dominant syndrome characterized by excessive bilateral maxillomandibular bony degeneration and fibrous tissue hyperplasia. Conservative management is the preferred treatment as cherubism has a self-limiting course. Functional or emotional disturbances may, however, demand surgical intervention. We report a patient who underwent surgical intervention. METHOD/DESCRIPTION: He had significant enlargement of lower cheeks and bilateral lower lid scleral show. On computed tomography of the face, the patient had significant fibrous tissue involving bilateral maxilla and mandible. The mandibular tumor was excised. Given normal inferior border, bilateral sagittal split osteotomy was performed to infracture and inset the outer cortex. During the procedure, patient required blood transfusion intraoperatively, so the maxillary portion of the procedure was delayed until 6 months later. For the maxilla, bilateral transconjunctival approach was used to resect parts of the orbital floors that were concave, resulting in 1 × 2 cm defects bilaterally which were reconstructed using resorbable plates. Then the anterior maxillary tumor was excised. RESULTS: The patient and his parents were satisfied with his appearance after surgery. The patient was noted to have improvement in contour and decreased scleral show. He has most recently followed up 15 months after the initial surgery. There were no long-term complications. CONCLUSIONS: Severity of cherubism influences the type of surgical intervention. The present case is innovative because this is the first reported case of recontouring orbital floors with resorbable plates and infracturing of the mandible using sagittal split osteotomies for surgical treatment of cherubism.

Precision and reliability of Dolphin 3-dimensional voxel-based superimposition.

INTRODUCTION: Superimposition of 2 cone-beam computed tomography images is possible by using landmarks, surfaces, or density information (voxel-based). Voxel-based superimposition is automated and uses the most image content, providing accurate results. Until recently, this superimposition was extremely laborious, but a user-friendly voxel-based superimposition has recently been introduced. Our aim was to evaluate the precision and reliability of Dolphin 3-dimensional voxel-based superimposition (Dolphin Imaging, Chatsworth, Calif). METHODS: This was a retrospective study using existing scans of 31 surgical orthodontic patients with a mean age of 21 ± 8 years (range, 15-47 years). Each patient had a presurgical and a postsurgical scan taken within 12 months. Surgical patients were used since the reference area for superimposition was not affected by growth or surgical procedures. The volumes were superimposed using voxel-based methods from Dolphin Imaging and a tested method used previously. This method uses 2 open-source programs and takes about 3 hours to complete, whereas the Dolphin method takes under 5 minutes. The postsurgical scan was superimposed on the presurgical scan at the cranial base. Postsurgical registrations for both methods were compared with each other using the absolute closest point color map, with emphasis on 7 regions (nasion, A-point, B-point, bilateral zygomatic arches, and bilateral gonions). RESULTS: Intraclass correlations showed excellent reliability (0.96). The mean differences between the 2 methods were less than 0.21 mm (voxel size, 0.38). The smallst difference was in the left zygomatic area at 0.09 ± 0.07 mm, and the largest was in the right gonial region at 0.21 ± 0.13 mm. CONCLUSIONS: Dolphin 3-dimensional voxel-based superimposition, a fast and user-friendly method, is precise and reliable.

Effects of Case Western Reserve University's transverse analysis on the quality of orthodontic treatment.

INTRODUCTION: The purpose of this study was to evaluate the effect of using the transverse analysis developed at Case Western Reserve University (CWRU) in Cleveland, Ohio. The hypotheses were based on the following: (1) Does following CWRU's transverse analysis improve the orthodontic results? (2) Does following CWRU's transverse analysis minimize the active treatment duration? METHODS: A retrospective cohort research study was conducted on a randomly selected sample of 100 subjects. The sample had CWRU's analysis performed retrospectively, and the sample was divided according to whether the subjects followed what CWRU's transverse analysis would have suggested. The American Board of Orthodontics discrepancy index was used to assess the pretreatment records, and quality of the result was evaluated using the American Board of Orthodontics cast/radiograph evaluation. The Mann-Whitney test was used for the comparison. RESULTS: CWRU's transverse analysis significantly improved the total cast/radiograph evaluation scores (P = 0.041), especially the buccolingual inclination component (P = 0.001). However, it did not significantly affect treatment duration (P = 0.106). CONCLUSIONS: CWRU's transverse analysis significantly improves the orthodontic results but does not have significant effects on treatment duration.