Search

Introduction: The objectives of this prospective clinical study were to evaluate the quality of treatment outcomes achieved with a complex orthodontic finishing protocol involving serpentine wires and a tooth positioner, and to compare it with the outcomes of a standard finishing protocol involving archwire bends used to detail the occlusion near the end of active treatment. Methods: The complex finishing protocol sample consisted of 34 consecutively treated patients; 1 week before debonding, their molar bands were removed, and serpentine wires were placed; this was followed by active wear of a tooth positioner for up to 1 month after debonding. The standard finishing protocol group consisted of 34 patients; their dental arches were detailed with archwire bends and vertical elastics. The objective grading system of the American Board of Orthodontics was used to quantify the quality of the finish at each time point. The Wilcoxon signed rank test was used to compare changes in the complex finishing protocol; the Mann-Whitney U test was used to compare changes between groups. Results: The complex finishing protocol group experienced a clinically significant improvement in objective grading system scores after treatment with the positioner. Mild improvement in posterior space closure was noted after molar band removal, but no improvement in the occlusion was observed after placement of the serpentine wires. Patients managed with the complex finishing protocol also had a lower objective grading system score (14.7) at the end of active treatment than did patients undergoing the standard finishing protocol (23.0). Conclusions: Tooth positioners caused a clinically significant improvement in interocclusal contacts, interproximal contacts, and net objective grading system score; mild improvement in posterior band space was noted after molar band removal 1 week before debond. [ABSTRACT FROM AUTHOR]

Objective: To assess the short- and long-term dentoskeletal effects of early Class III treatment with rapid maxillary expansion and facemask (RME/FM) followed by fixed appliances., Materials and Methods: A total of 44 patients (27 females, 17 males) treated consecutively with RME/FM were included from the archives of 3 centres. Three lateral cephalograms were available: T0 (before the start of RME/FM therapy, mean age 8.1 ± 1.8 years), T1 (immediately after RME/FM, mean age 9.8 ± 1.6 years), and T2 (long-term observation, mean age 19.5 ± 1.6 years). A control group of 17 untreated Class III subjects (12 females and 5 males) also was selected. Between-group statistical comparisons were performed with ANCOVA., Results: No statistically significant differences for any of the cephalometric variables were found at T0. In the short term, the treated group showed significant improvements in ANB (+2.9°), Wits appraisal (+2.7 mm), SNA (+1.8°) and SNB (-1.1°). A significant closure of CoGoMe angle (-1.3°) associated with smaller increments along Co-Gn (-2.4 mm) also was found together with a significant increase in intermaxillary divergence (+1.3°). In the long-term, significant improvements in ANB (+2.6°), Wits appraisal (+2.7 mm) and SNB (-1.7°) were recorded together with a significant closure of the CoGoMe angle (-2.9°). No significant long-term changes in vertical skeletal relationships were found., Conclusions: RME/FM therapy was effective in improving Class III dentoskeletal relationships in the short term. These changes remained stable in the long-term due mainly to favourable mandibular changes., (© 2023 The Authors. Orthodontics & Craniofacial Research published by John Wiley & Sons Ltd.)

Objective: To compare the effects on facial soft tissues produced by maxillary expansion generated by rapid maxillary expansion (RME) versus slow maxillary expansion (SME)., Materials and Methods: Patients in the mixed dentition were included with a transverse discrepancy between the two arches of at least 3 mm. A conventional RME screw was compared to a new expansion screw (Leaf expander) designed to produce SME. Both screws were incorporated in a fixed expander. The primary outcome was the difference of the facial tissue changes in the nasal area measured on facial 3D images captured immediately before application of the expander (T0) and after one year of retention, immediately after the expander removal (T1). Secondary outcomes were soft tissue changes of other facial regions (mouth, lips, and chin). Analysis of covariance was used for statistical analysis., Results: Fourteen patients were allocated to the RME group, and 14 patients were allocated to the SME group. There were no dropouts. Nasal width change showed a difference between the two groups (1.3 mm greater in the RME group, 95% CI from 0.4 to 2.2, P = 0.005). Also, intercanthal width showed a difference between treatments (0.7 mm greater in the RME group, 95% CI from 0.0 to 1.3, P = 0.044). Nasal columella width, mouth width, nasal tip angle, upper lip angle, and lower lip angle did not show any statistically significant differences. The Y-axis (anterior-posterior) components of the nasal landmark showed a statistically significant difference between the two groups (0.5 mm of forward displacement greater in the RME group, 95% CI from 0.0 to 1.2, P = 0.040). Also, Z-axis (superior-inferior) components of the lower lip landmark was statistically significant (0.9 mm of downward displacement in favor of the RME group, 95% CI from 0.1 to 1.7, P = 0.027). All the other comparisons of the three-dimensional assessments were not statistically significant., Conclusions: RME produced significant facial soft tissue changes when compared to SME. RME induced greater increases in both nasal and intercanthal widths (1.3 mm and 0.7 mm, respectively). These findings, though statistically significant, probably are not clinically relevant. Trial registration ISRCTN, ISRCTN18263886. Registered 8 November 2016, https://www.isrctn.com/ISRCTN18263886?q=Franchi&filters=&sort=&offset=2&totalResults=2&page=1&pageSize=10., (© 2023. The Author(s).)

Introduction: This study aimed to quantify the outcomes of adolescent patients with Class II malocclusion treated with the Carriere Motion 3D Appliance (CMA) combined with full fixed appliances., Methods: Cone-beam computed tomography scans of 22 patients were available before orthodontic treatment (T1), at removal of the CMA (T2), and posttreatment (T3). The average age of the patients was 13.5 ± 1.6 years at T1, 14.1 ± 0.2 years at T2, and 15.6 ± 0.5 years at T3. The 3-dimensional image analysis procedures were performed using ITK-SNAP (version 3.6.0; www.itksnap.org, Hatfield, Pa) and SlicerCMF (version 4.11.0; http://www.slicer.org, Cambridge, Mass); skeletal and dentoalveolar changes relative to cranial base, maxillary, and mandibular regional superimpositions were evaluated., Results: Changes were analyzed with 1 sample t tests using the mean differences during the CMA phase (T1 to T2) and total treatment time (T1 to T3). Significant skeletal changes included a slight reduction of ANB from T1 to T3, mandibular growth (Co-Gn increment of 1.2 mm and 3.3 mm from T1 to T2 and T1 to T3, respectively), inferior displacement of point A, and anterior and inferior displacement of point B. The mandibular plane did not change significantly during treatment. During the CMA treatment, posterior tipping and distal rotation of the maxillary molars, tip back and inferior displacement of the maxillary canines, significant mesial rotation, and superior displacement of the mandibular molars were observed. These movements rebounded during the full fixed appliance phase except for the molar and canine vertical displacements. Clinically significant dental changes during treatment included a reduction in overjet and overbite, Class II correction of the molar and canine relationship, and proclination of the mandibular incisors., Conclusions: The CMA is an effective treatment modality for Class II correction in growing patients because of a combination of mesial movement of the mandibular molar, distal rotation of the maxillary molar, and anterior displacement of the mandible., (Copyright © 2023 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Background: to determine the role of treatment timing in the long-term effects produced by rapid maxillary expansion and facemask therapy (RME/FM) in Class III patients., Methods: This study compared two sample groups treated with RME/FM followed by fixed appliances: the early prepubertal group (EPG) (17 patients; mean age before treatment (T0), 5.8 ± 0.7 years; range, 4.3-6.9 years) and the late prepubertal group (LPG) (17 patients; mean age at T0, 10.1 ± 0.8 years; range, 9.0-11.1 years). Lateral cephalograms for the two groups were examined before treatment (T0) and at a long-term observation (T1) (EPG, 19.8 ± 1.0 years; LPG, 21.0 ± 2.1 years). Independent sample t -tests were performed to compare the two groups at T0 and T1., Results: No statistically significant differences were found for any of the cephalometric variables at T0, except for the total mandibular length, overjet, and inclination of the maxillary incisors to the palatal plane, which were greater in the LPG. At T1, no statistically significant differences were detected for any of the cephalometric variables., Conclusions: There were no significant long-term differences when treating Class III patients with RME/FM, either during an early prepubertal phase (≤7 years of age) or during a late prepubertal phase (≥9 years of age).

Objective: To compare the transverse dental and skeletal changes in patients treated with bone-anchored palatal expander (bone-borne, BB) compared to patients treated with tooth and bone-anchored palatal expanders (tooth-bone-borne, TBB) using cone-beam computer tomography (CBCT) and 3D image analysis., Methods: The sample comprised 30 patients with transverse maxillary discrepancy treated with two different types of appliances: bone-borne (Group BB) and tooth-bone-borne (Group TBB) expanders. CBCT scans were acquired before (T1) and after completion of maxillary expansion (T2); the interval was 5.4 ± 3.4 and 6.2 ± 2.1 months between the T1 and the T2 scans of Group TBB (tooth-bone-borne) and Group BB (bone-borne), respectively. Transverse, anteroposterior and vertical linear and angular three-dimensional dentoskeletal changes were assessed after cranial base superimposition., Results: Both groups displayed marked transverse skeletal expansion with a greater ratio of skeletal to dental changes. Greater changes at the nasal cavity, zygoma and orbital levels were found in Group BB. A relatively parallel sutural opening in an anterior-posterior direction was observed in Group TBB; however, the Group BB presented a somewhat triangular (V-shaped) opening of the suture that was wider anteriorly. Small downward-forward displacements were observed in both groups. Asymmetric expansion occurred in approximately 50% of the patients in both groups., Conclusion: Greater skeletal vs dental expansion ratio and expansion of the circummaxillary regions were found in Group BB, the group in which a bone-borne expander was used. Both groups presented skeletal and dental changes, with a similar amount of posterior palate expansion. Asymmetric expansion was observed in both groups., (© 2022 The Authors. Orthodontics & Craniofacial Research published by John Wiley & Sons Ltd.)

Treatment effects occurring during Class II malocclusion treatment with the clear aligner mandibular advancement protocol were evaluated in two growing patients: one male (12 years, 3 months) and one female (11 years, 9 months). Both patients presented with full cusp Class II molar and canine relationships. Intraoral scans and cone-beam computed tomography were acquired before treatment and after mandibular advancement. Three-dimensional skeletal and dental long-axis changes were quantified, in which the dental long axis was determined by registering the dental crowns obtained from intraoral scans to the root canals in cone-beam computed tomography scans obtained at the same time points. Class II correction was achieved by a combination of mandibular skeletal and dental changes. A similar direction of skeletal and dental changes was observed in both patients, with downward and forward displacement of the mandible resulting from the growth of the mandibular condyle and ramus. Dental changes in both patients included mesialization of the mandibular posterior teeth with flaring of mandibular anterior teeth. In these two patients, clear aligner mandibular advancement was an effective treatment modality for Class II malocclusion correction with skeletal and dental effects and facial profile improvement., Competing Interests: CONFLICTS OF INTEREST All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest, and none were reported.

Purpose: The study was aimed at evaluating the sagittal and transversal inclinations of upper second molars in untreated adolescents with normal occlusion., Methods: A sample of 41 subjects (16 females, 25 males) was selected from the University of Michigan Growth Study (UMGS). Digital dental casts with fully erupted second molars in occlusion were chosen (mean age 14.9 ± 1.3 years). Digital measurements were recorded with the open source software 3D Slicer ( www.slicer.org ). The digital measurements of the UMGS sample were compared with the manual measurements collected by Andrews from his sample of untreated class I subjects with normal overbite and overjet. Two mixed effect models (sagittal and transversal inclinations) were performed. The "random effect" was represented by the subjects, while the "fixed effects" were the two compared groups, the side of the arch (right and left), and the group × side interaction. Outcome variables were sagittal and transversal inclinations of the upper second molars., Results: The UMGS group showed a significantly greater distal crown angulation (-18.9°) with respect to the Andrews sample (0.4°, P < 0.0001). As for the transversal inclination, the UMGS group exhibited significantly greater lingual crown inclination (-10.6° versus -8.0°, P = 0.0118)., Conclusions: Fully erupted maxillary second molars in a sample of adolescent subjects with normal occlusion showed significantly greater distal and lingual inclinations when compared with Andrews' values. The finding of a distal crown inclination in contrast with Andrews' observation of a mesial crown inclination suggests that revision in tip prescription for preadjusted brackets may be considered., (© 2021. Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Introduction: The purpose of the present study was to evaluate the long-term variations in maxillary second molar position in untreated subjects with normal occlusion., Setting and Sample Population: A sample of 39 subjects (18 females and 21 males) selected from the University of Michigan Growth Study (UMGS) was followed longitudinally with digital dental casts at 3 observation times: T1, when the maxillary permanent second molars were fully erupted, T2, last observation available in the longitudinal series (38 subjects), and T3, at least 20 years after T2 (12 subjects)., Materials and Methods: Digital measurements were recorded with an open-source software. Outcome variables were sagittal and transverse inclinations of the upper second molars. Two mixed-effect models were performed., Results: The maxillary second molars had a distolingual inclination at T1, T2 and T3. Sagittal and transverse inclination showed progressive significant uprighting from T1 through T3 (P < .001). From T1 to T2, the adjusted difference in sagittal crown inclination was 8.0° (95% CI from 6.5° to 9.6°; P < .001). From T2 to T3, the adjusted difference was 5.5° (95% CI from 3.0° to 8.1°; P < .001). From T1 to T2, the adjusted difference in transverse crown inclination was 1.9° (95% CI from 0.4° to 3.5°; P = .011). From T2 to T3, the adjusted difference was 6.0° (95% CI from 3.4° to 8.5°; P < .001)., Conclusions: Along with age, maxillary second molars showed a progressive significant uprighting with a decrease in the distal and lingual inclinations., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: The objective was to determine the skeletal and dental changes with microimplant assisted rapid palatal expansion (MARPE) appliances in growing (GR) and nongrowing (NG) patients using cone-beam computed tomography and 3-dimensional imaging analysis., Methods: The sample consisted of 25 patients with transverse maxillary discrepancy treated with a maxillary skeletal expander, a type of MARPE appliance. Cone-beam computed tomography scans were taken before and after maxillary expansion; the interval was 6.0 ± 4.3 months. The sample was divided into GR and NG groups using cervical vertebral and midpalatal suture maturation. Linear and angular 3-dimensional dentoskeletal changes were assessed after cranial base superimposition. Groups were compared with independent-samples t test (P <0.05)., Results: Both groups displayed marked transverse changes with a similar ratio of skeletal to dental transverse changes and parallel sutural opening from the posterior nasal spine-anterior nasal spine; a similar amount of expansion occurred in the anterior and the posterior regions of the maxilla. The maxilla expanded skeletally without rotational displacements in both groups. The small downward-forward displacements were similar in both groups, except that the GR group had a significantly greater vertical displacement of the canines (GR, 1.7 ±1.0 mm; NG, 0.6 ± 0.8 mm; P = 0.02) and anterior nasal spine (GR, 1.1 ± 0.6 mm; NG, 0.5 ± 0.5 mm; P = 0.004)., Conclusions: Treatment of patients with MARPE appliance is effective in GR and NG patients. Although greater skeletal and dental changes were observed in GR patients, a similar ratio of skeletal to dental transverse changes was observed in both groups., (Copyright © 2021 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to develop a prediction model that combines the information derived from chronological age (analysed as a curvilinear variable), gender and the CVM method to predict mandibular growth., Settings and Sample Population: 50 participants (29 females, 21 males) were selected from the AAOF Craniofacial Growth Legacy Collection, the Michigan Growth Study and the Denver Child Growth study., Materials and Methods: In this investigation, 456 lateral cephalograms were analysed by applying a mixed effect model. The outcome variable was the annualized increment in total mandibular length (Co-Gn) during the year following the lateral cephalogram on which the cervical stage and chronological age were evaluated. The predictive variables were chronological age up to the fifth order, gender, stage of cervical vertebral maturation, as well as interactions between age and gender, age and cervical stage, and gender and cervical stage., Results: Cervical stage, chronological age up to the fourth order, gender, and the interaction between age and gender were significant predictors of annualized increments in mandibular length. The annualized increment in Co-Gn was significantly greater for CS 3 when compared to all other cervical stages. Further, annualized increments in Co-Gn for CS 1 and CS 2 were significantly greater when compared to CS 5., Conclusions: Cervical stage, chronological age and gender can be used jointly to predict the annualized increment in mandibular growth. Cervical stage 3 exhibited the greatest annualized increase in mandibular length., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: This study aimed to evaluate the 3-dimensional (3D) mandibular dental changes over 42 years using the registration of digital models., Methods: The sample comprised digital dental models of 8 untreated subjects (4 males and 4 females) with normal occlusion measured longitudinally at ages 17 years (T1) and 60 years (T2). Using 13 landmarks placed on the mucogingival junction, we registered the T2 model on the T1 model. Three-dimensional changes in the position of the landmarks on the buccal cusp tip of the posterior teeth and incisal edge of the central incisors were measured by 2 examiners. Registration and measurements were performed using SlicerCMF (version 3.1; http://www.slicer.org) software. Intra- and interrater agreements were evaluated using intraclass correlation coefficients and the Bland-Altman method. One-sample t tests were used for evaluating interphase 3D dental changes (P <0.05)., Results: Adequate intra- and interrater reproducibility was found. From T1 to T2, the mandibular teeth showed significant 3D positional changes. A significant dental eruption relative to the mucogingival junction was observed for the anterior and posterior teeth. Anteroposterior movements of mandibular teeth were not significant except for the right molar that drifted mesially. Transverse movements included slight lingual tipping at canines and premolars regions., Conclusions: Dental changes in untreated normal occlusion were very slight from early to mature adulthood. The eruption of the mandibular teeth was the most consistent finding. A tendency for mesial movement of molars and lingual movement of first premolars and canines was observed in the mandible during the aging process., (Copyright © 2020 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: During the decision-making process, physicians rely on heuristics that consist of simple, useful procedures for solving problems, intuitive shortcuts that produce reliable decisions based on limited information. In clinical situations characterized by a high degree of uncertainty such as those encountered in orthodontics, cognitive biases and judgment errors related to heuristics are not uncommon. This study aimed at promoting trust in the effective interface between the intuitive reasoning of the orthodontic practitioner and the computational heuristics emerging from simple statistical models., Methods: We propose an integrative model based on the interaction between clinical reasoning and 2 computational tools, cluster analysis and fast-and-frugal trees, to extract a structured craniofacial representation of untreated subjects with Class III malocclusion and to forecast the worsening of the malocclusion over time., Results: Cluster analysis of cephalometric values from 144 growing subjects with Class III malocclusion followed longitudinally (T1: mean age, 10.2 ± 1.9 years; T2: mean age, 13.8 ± 2.7 years) produced 3 morphologic subgroups with predominant sagittal, vertical, and slight maxillomandibular imbalances. Fast-and-frugal trees applied to different subgroups extracted heuristics that improved the prediction of key features associated with adverse craniofacial growth., Conclusions: Provided that cephalometric values are placed in the appropriate framework, the matching between simple and fast computational approaches and clinical reasoning could help the intuitive logic, perception, and cognitive inferences of orthodontic practitioners on the outcome of patients affected by Class III disharmony, decreasing errors associated with flawed judgments and improving the accuracy of decision making., (Copyright © 2020. Published by Elsevier Inc.)

Objective: To analyse the craniofacial growth of a long-term semi-longitudinal sample of Caucasian subjects with untreated Class III malocclusion., Setting and Sample Population: A total of 144 Caucasian subjects (of North American and Italian origin) with untreated Class III malocclusion., Materials and Methods: Subjects aged 2 years and 9 months up to 21 years and 7 months were selected. A multilevel model was used to calculate growth curves for ten variables for both each individual subject and for the whole sample., Results: There was a statistically significant increase for total mandibular length (Co-Gn. T2-T1 = 8.4 mm), midfacial length (Co-A. T2-T1 = 3.4 mm) and lower anterior facial height (ANS-Me. T2-T1 = 3.8 mm). The multilevel analysis showed two points of acceleration of growth (about 3-5 years of age and 11-15 years of age) for seven out of ten variables. For Co-Gn and Co-A variables, males presented points of maximum growth delayed by 1 year in comparison with females, with a greater duration (1 year longer) and a greater total growth of about 5 mm. Active mandibular growth continued for a long time after the pubertal spurt: increases in mandibular length ended at about 17 years of age in females and at 21 years and 7 months in males., Conclusions: Untreated Class III malocclusion showed a specific growth curve, especially for the mandible, whose excesses added up over time. In males, the amounts of mandibular and midfacial growth during the whole observation time were greater and lasted longer than in females., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: This study aimed to determine the volumetric effects on the upper airways of growing patients with Class II malocclusion treated with the Herbst appliance (HA)., Methods: Volumetric measurements of the upper airways of 42 skeletal Class II malocclusion patients (mean age: 13.8 ± 1.2 years; ranging from 12.0 to 16.9 years) were assessed using cone-beam computed tomography scans acquired before treatment (T0) and approximately 1 year later (T1). The sample comprised a Herbst appliance group (HA group [HAG]; n = 24), and a comparison group (comparison group [CG]; n = 18) of orthodontic patients who had received dental treatments other than mandibular advancement with dentofacial orthopedics., Results: In CG, nasopharynx and oropharynx volumes decreased slightly during the observation period (9% and 3%, respectively), whereas the nasal cavity volume increased significantly (12%; P = 0.046). In HAG, there was an increase in the volume of all regions (nasal cavity, 5.5%; nasopharynx, 11.7%; and oropharynx, 29.7%). However, only the oropharynx showed a statistically significant increase (P = 0.003), presenting significant volumetric changes along the time (T1-T0) in HAG., Conclusion: Mandibular advancement with the HA significantly increased the volume of the oropharynx, but no significant volumetric modifications were observed in the nasal cavity and nasopharynx., (Copyright © 2019 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The aim of this 2-arm parallel trial was to compare the dentoskeletal effects of the expander with differential opening (EDO) and the Hyrax expander in the mixed dentition., Methods: Patients aged 7-11 years with maxillary dental arch constriction and Class I or Class II sagittal relationships were randomly allocated into 2 study groups. The experimental group comprised 22 patients (10 males, 12 females) with a mean age of 8.46 years treated with the EDO. The comparison group was composed of 24 patients (6 males, 18 females), mean age of 8.92 years treated with the conventional Hyrax expander. One complete turn per day for 6 days was performed for the posterior screw of the EDO and for the Hyrax expander. The anterior screw of the EDO was activated 1 complete turn per day for 10 days. The primary outcomes were the anterior opening of the midpalatal suture, changes on the interincisal diastema width, maxillary dental arch widths, arch perimeter, arch length, palatal depth, inclination of maxillary posterior teeth and on dental arch shape, and the amount of differential expansion in the anterior region compared with the posterior region of the maxillary dental arch. Computer-generated randomization was used. Allocation was concealed with sequentially, numbered, sealed, and opaque envelopes. Blinding was applicable for outcome assessment only. Occlusal radiographs of the maxilla were obtained at the end of the active expansion phase (T2). Intraoral photographs were obtained immediately pre-expansion (T1) and at T2. Digital dental models were obtained at T1 and 6 months after the active expansion period (T3). Intergroup comparisons of T1-T2 changes were performed using multiple linear regression analysis (P < 0.05). The independent variables were both treatment and the starting forms. Bonferroni correction for multiple tests was applied., Results: The experimental group showed a significantly greater opening of the anterior region of the midpalatal suture, a greater increase of the interincisal diastema width, and greater increases of the intercanine distance and inter-first deciduous molar distance than the Hyrax expander. The experimental group showed a significant differential expansion between the anterior and posterior regions, whereas the Hyrax group produced a similar expansion in the canine and molar regions. Serious harm was not observed., Conclusions: The EDO was capable of promoting greater orthopedic and dental changes in the anterior region of the maxilla than the conventional Hyrax expander. Similarity between the 2 expanders was observed for changes in the posterior region width, arch perimeter, arch length, palatal depth, and posterior teeth inclination., (Copyright © 2019 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objectives: To perform a three-dimensional evaluation of the position of the condyles in patients treated with Herbst appliance (HA) in two stages of cervical vertebral maturation., Setting and Sample Population: Retrospective case-control study. Pubertal Herbst group (PHG; n = 24, mean age 14.5 years, CS 3 and CS 4) and pre-pubertal Herbst group (PPHG; n = 17, mean age 9.9 years, CS 1 and CS 2) were contrasted with comparison groups of non-orthopaedically treated Class II patients in pubertal (PCG; n = 17, mean age 13.9 years) and pre-pubertal maturational stages (PPCG; n = 18, mean age 10.6 years)., Materials and Methods: Cone-beam computer tomography scans were taken before treatment (T0) and at T1 after 8 to 12 months. Point-to-point measurements of the displacement of the condyles between T0 and T1, relative to the glenoid fossae, were performed in the X, Y, Z and 3D perspectives. Qualitative assessments using semi-transparent overlays and colour mapping also were produced., Results: The displacement of the condyles within the glenoid fossae in the treated groups was small (<0.75 mm; P > .05). Relative to the glenoid fossa, condylar position at T1 was similar to T0 in pre-pubertal and pubertal groups (P > .05). Similar condylar rotations from T0 to T1 were observed in Herbst and comparison groups, and no significant difference was found between pre-pubertal and pubertal patients., Conclusions: Regardless the stage of skeletal maturation, HA treatment did not change the condyle-glenoid fossa relationship., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: To determine the treatment effects produced in Class II patients by the Carriere ® Motion 3D™ appliance (CMA) followed by full fixed appliances (FFA)., Materials and Methods: This retrospective study evaluated 34 adolescents at three time points: T1 (pretreatment), T2 (removal of CMA), and T3 (posttreatment). The comparison group comprised 22 untreated Class II subjects analyzed at T1 and T3. Serial cephalograms were traced and digitized, and 12 skeletal and 6 dentoalveolar measures were compared., Results: Phase I with CMA lasted 5.2 ± 2.8 months; phase II with FFA lasted 13.0 ± 4.2 months. CMA treatment restricted the forward movement of the maxilla at point A. There was minimal effect on the sagittal position of the chin at pogonion. The Wits appraisal improved toward Class I by 2.1 mm during the CMA phase but not during FFA. Lower anterior facial height increased twice as much in the treatment group as in controls. A clockwise rotation (3.9°) of the functional occlusal plane in the treatment group occurred during phase I; a substantial rebound (-3.6°) occurred during phase II. Overjet and overbite improved during treatment, as did molar relationship; the lower incisors proclined (4.2°)., Conclusions: The CMA appliance is an efficient and effective way of correcting Class II malocclusion. The changes were mainly dentoalveolar in nature, but some skeletal changes also occurred, particularly in the sagittal position of the maxilla and in the vertical dimension.

Objectives: The aim of this study was to evaluate the reliability of 3-dimensional maxillary dental changes using two methods of digital model superimposition., Setting and Sample Population: The Department of Orthodontics of Bauru Dental School, University of São Paulo and University of Michigan Craniofacial Growth Center. Fifteen subjects with normal occlusion., Material & Methods: The sample was composed of digital study models of 15 normal occlusion subjects taken at 13 (T1), 18 (T2) and 60 years of age (T3). Using the software SlicerCMF 3.1, superimposition (registration) was conducted using 9 landmarks placed on the incisive papilla, second and third palatal rugae and 10 mm distal to the third palatal rugae. Two registration methods were compared: landmarks (LA) and regions of interest (ROI). Three-dimensional changes of landmarks on the buccal cusp tip of posterior teeth bilaterally and the incisal edge of the right central incisor were measured by three examiners. Intraclass correlation coefficients and Bland-Altman method evaluated intra- and inter-examiner agreements., Results: Good or excellent intra-examiner agreement was found for T1-T2 and T2-T3 measurements using both registration methods. Inter-examiner agreements were good to excellent for T1-T2 measurements and poor to fair for most T2-T3 measurements. Mean T1-T2 differences were less than 0.5 mm for most measurements., Conclusion: Maxillary digital dental models of patients with normal occlusion superimposed on palatal rugae showed an adequate reliability for a 5-year interval comparison using landmarks or regions of interest. Lower than acceptable reproducibility using both superimposition methods was found for a 40-year interval comparison., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The aim of the study was to investigate how to improve the forecasting of craniofacial unbalance risk during growth among patients affected by Class III malocclusion. To this purpose we used computational methodologies such as Transductive Learning (TL), Boosting (B), and Feature Engineering (FE) instead of the traditional statistical analysis based on Classification trees and logistic models. Such techniques have been applied to cephalometric data from 728 cross-sectional untreated Class III subjects (6-14 years of age) and from 91 untreated Class III subjects followed longitudinally during the growth process. A cephalometric analysis comprising 11 variables has also been performed. The subjects followed longitudinally were divided into two subgroups: favourable and unfavourable growth, in comparison with normal craniofacial growth. With respect to traditional statistical predictive analytics, TL increased the accuracy in identifying subjects at risk of unfavourable growth. TL algorithm was useful in diffusion of information from longitudinal to cross-sectional subjects. The accuracy in identifying high-risk subjects to growth worsening increased from 63% to 78%. Finally, a further increase in identification accuracy, up to 83%, was produced by FE. A ranking of important variables in identifying subjects at risk of growth worsening, therefore, has been obtained.

Objectives:: The purpose of this three-dimensional (3D) study was to assess retrospectively the middle cranial fossa and central skull base of patients treated with the Herbst appliance (HA)., Materials and Methods:: 3D surface virtual models of 40 Class II, division 1 malocclusion patients were generated from cone-beam computed tomography (CBCT) acquired before treatment (T0) and after 8 months of HA treatment (T1). T0 and T1 3D models were superimposed volumetrically at the anterior cranial fossa. Twenty subjects who had been treated with the Herbst appliance (HAG) were compared to 20 subjects who were not treated orthopedically. The latter group served as a comparison control group (CG). Quantitative assessments of the location and directional changes were made with linear and angular measurements between anatomical landmarks. Qualitative assessments of the spatial behavior of the middle cranial fossa and central skull base relative to the anterior cranial fossa were displayed graphically for visualization with color maps and semitransparent overlays. Non-parametric tests were performed to compare the between the HAG and CG., Results:: Point-to-point linear measurements and skeletal rotation (pitch, roll, and yaw) changes were very small along the observational period and were not significantly different between HAG and CG. Visual analysis of color maps and overlays confirmed that no changes in the cranial base were associated with HA., Conclusions:: HA therapy did not produce clinically significant changes in the middle cranial fossa and central skull base.

Objectives: To compare the three-dimensional maxillary dentoskeletal effects of a modified alternate rapid maxillary expansion and constriction facemask protocol (Alt-RAMEC/FM) with the traditional rapid maxillary expansion facemask protocol (RME/FM) performed in deciduous or early mixed dentition Class III patients., Setting and Sample Population: Orthodontic Clinic of the Section of Dentistry of the Department of Surgery and Translational Medicine of the University of Florence. Thirty-four Class III patients were enrolled and allocated by alternating assignment to either Alt-RAMEC/FM or RME/FM therapy., Materials and Methods: Prior to treatment, all patients were evaluated, and a cone beam computed tomography (CBCT) scan was acquired. After completion of the orthopaedic therapy (average interval 1.2 years), a follow-up CBCT scan was obtained. Anatomic landmark identification on the CBCTs and subsequent quantification of the changes were performed. The primary outcome variable was the anteroposterior displacement of the anterior nasal spine (ANS AP). The treatment groups were compared with independent samples t tests., Results: The patients in the two treatment groups showed a similar degree of compliance. No statistically significant differences were recorded for any variable when comparing the Alt-RAMEC/FM and RME/FM groups. In particular, the between-group difference for ANS AP was 0.0 mm (95%CI: -0.6;0.7, P = 0.933)., Conclusions: Both Alt-RAMEC/FM and RME/FM produced favourable orthopaedic changes in Class III growing patients. Neither protocol was superior to the other in terms of maxillary protraction effectiveness., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To evaluate the role of treatment timing on long-term dentoskeletal effects of Class II treatment with removable functional appliances followed by full-fixed appliance therapy., Materials and Methods: A group of 46 patients (23 females and 23 males) with Class II malocclusion treated consecutively with either Bionator or Activator, followed by fixed appliances was compared with a matched control group of 31 subjects (16 females and 15 males) with untreated Class II malocclusion. The treated sample was evaluated at T1, start of treatment (mean age: 9.9 ± 1.3 years); T2, end of functional treatment and prior to fixed appliances (mean age: 11.9 ± 1.3 years); and T3, long-term observation (mean age: 18.3 ± 2.1 years). The treated and the control samples were divided into pre-pubertal and pubertal groups according to skeletal maturity observed at the start of treatment. Statistical comparisons were performed with independent sample t-tests., Results: When treatment was initiated before puberty, Class II correction was mostly confined to the dentoalveolar changes, with significant improvements of both overjet and molar relationships. On the other hand, treatment with the outset at puberty produced significant long-term improvement of sagittal skeletal relationships, which were mainly sustained by mandibular changes., Conclusions: Treatment with removable functional appliances (Bionator or Activator) followed by full-fixed appliances produced significant skeletal long-term changes when it begins at puberty. Prepubertal Class II treatment results primarily in dentoalveolar changes.

The cervical vertebral maturation (CVM) method is used to determine the craniofacial skeletal maturational stage of an individual at a specific time point during the growth process. This diagnostic approach uses data derived from the second (C2), third (C3), and fourth (C4) cervical vertebrae, as visualized in a two-dimensional lateral cephalogram. Six maturational stages of those three cervical vertebrae can be determined, based on the morphology of their bodies. The first step is to evaluate the inferior border of these vertebral bodies, determining whether they are flat or concave (ie, presence of a visible notch). The second step in the analysis is to evaluate the shape of C3 and C4. These vertebral bodies change in shape in a typical sequence, progressing from trapezoidal to rectangular horizontal, to square, and to rectangular vertical. Typically, cervical stages (CSs) 1 and CS 2 are considered prepubertal, CS 3 and CS 4 circumpubertal, and CS 5 and CS 6 postpubertal. Criticism has been rendered as to the reproducibility of the CVM method. Diminished reliability may be observed at least in part due to the lack of a definitive description of the staging procedure in the literature. Based on the now nearly 20 years of experience in staging cervical vertebrae, this article was prepared as a "user's guide" that describes the CVM stages in detail in attempt to help the reader use this approach in everyday clinical practice.

The aim of this study was to evaluate midpalatal suture maturation in adults, as observed in cone beam computed tomography (CBCT) images. CBCT scans from 78 subjects (64 female and 14 male, age range from 18 to 66 years) were evaluated. Midpalatal suture maturation was verified on the central cross-sectional axial slice in the superior-inferior dimension of the palate, using methods validated previously. Intra-examiner agreement was analyzed by weighted kappa test. Multinomial logistic regression was used to test whether sex and chronological age (adults <30 years or ≥30 years) could be used as a predictor for the maturational stages of the midpalatal suture. The majority of the adults presented a fused midpalatal suture in the palatine (stage D) and/or maxillary bones (stage E). However, the midpalatal suture was not fused in 12% of the subjects. Sex and chronological age were not significant predictors of the maturational stages of the midpalatal suture. The individual assessment of midpalatal suture maturation by way of CBCT images may provide reliable information critical to making the clinical decision between rapid maxillary expansion and surgically assisted rapid maxillary expansion for the treatment of maxillary atresia in adults., (Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Objective: To evaluate the influence of the maturational stages of zygomaticomaxillary sutures (ZMS) on the response to maxillary protraction., Subjects and Methods: A total of 40 Class III patients were treated retrospectively with either a combination of rapid maxillary expansion and facial mask (RME/FM) or bone-anchored maxillary protraction (BAMP). The RME/FM group consisted of 18 patients (mean age 8.3 years), while the BAMP group was comprised of 22 patients (mean age 11.8 years). The initial CBCT images (T1) of the ZMSs were classified blindly. 3D models from CBCT images at the start and at the end of orthopaedic treatment were registered on the anterior cranial base, and corresponding structures were measured on colour-coded maps and semitransparent overlays. The amounts of protraction of the maxilla, zygoma, orbitale and maxillary first molars for both groups were analysed with two-way ANOVA with Holm-Sidak post hoc test for multiple comparisons., Results: A significant association was found between the early maturation stages of the ZMSs and the amount of maxillary protraction, regardless of the protraction method used. Class III patients with ZMS stages A and B showed greater maxillary protraction than patients at stage C., Conclusion: The maturational stages of ZMS are associated with the response maxillary protraction., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The aim of this study was to test the reproducibility of three-dimensional (3D) surface models of maxillary incisors and to propose a characterization of root morphology. The sample was comprised of pre-treatment cone-beam computed tomography (CBCT) images of fifty-five patients. The CBCTs were used to construct 3D surface models of the maxillary incisors. The reproducibility of surface models was tested by repeated construction of them by two observers. A 3D surface model that corresponded to the average of all lateral and all central incisors was generated. 3D surface distances and vector differences were calculated for each individual tooth and the average of the teeth considered. The corresponding points on the 3D surface mesh for each subgroup were compared statistically to those of the neutral subgroup using shape analysis MANCOVA and Hotelling's t-statistic (p < 0.05). Repeated construction of surface models demonstrated adequate inter-rater reproducibility. The distribution of 3D models into root morphology subgroups was: blunt (11% and 26% of the central and lateral incisors, respectively), conical (15% of the central incisors), long (27% and 20% of the central and lateral incisors, respectively), and short (15% and 4% of the central and lateral incisors, respectively). Compared to the neutral average, statistically significant differences in root morphology were found for blunt, long, conical, and short central incisors and for blunt, long, and short lateral incisors. We can conclude that 3D surface models construction for upper incisors is reproducible. 3D shape analysis using CBCT images allows a phenotypic characterization of incisor root morphology.

Objective: The aim of this study was to present a method of classifying the maturational level of the zygomaticomaxillary sutures (ZMSs)., Methods: Cone-beam CT (CBCT) images from 74 subjects (5.6-58.4 years) were examined to define the radiographic stages of ZMS maturation. Five stages of maturation of the ZMS were identified and defined: Stage A-uniform high-density sutural line, with no or little interdigitation; Stage B-scalloped appearance of the high-density sutural line; Stage C-two parallel, scalloped, high-density lines, separated in some areas by small low-density spaces; Stage D-fusion in the inferior portion of the suture; and Stage E-complete fusion. Intra- and inter-examiner agreements were evaluated by weighted kappa tests., Results: The intra- and inter-examiners reproducibility values demonstrated substantial to almost perfect agreement. No fusion of ZMSs was observed in patients up to 10 years of age. From 10 to 15 years, all maturational stages were identified. After 15 years of age, the majority of patients showed fusion of ZMSs., Conclusions: The classification of ZMS maturation using CBCT is a reliable method that allows the assessment of the morphology of the ZMSs in the individual patient., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: Three-dimensional evaluation of skeletal mandibular changes following Herbst appliance treatment., Setting and Sample Population: Retrospective case-control study, based on a sample size calculation. Twenty-five pubertal patients treated with Herbst appliance (HAG), and 25 matched Class II patients who received other non-orthopaedic dental treatments (CG)., Material and Methods: Three-dimensional models were generated from pre-treatment (T0) and post-treatment (T1) cone beam computed tomograms. Volumetric registration on the cranial base was used to assess mandibular displacement; volumetric regional registration was performed to evaluate mandibular growth. Quantitative measurements of X, Y, Z and 3D Euclidian changes, and also qualitative visualization by colour-mapping and semi-transparent overlays were obtained., Results: Downward displacement of the mandible was observed in both HAG and CG (2.4 mm and 1.5 mm, respectively). Significant forward displacement of the mandible was observed in the HAG (1.7 mm). HAG showed greater 3D superior and posterior condylar growth than the CG (3.5 mm and 2.0 mm, respectively). Greater posterior growth of the ramus was noted in the HAG than in CG., Conclusions: Immediately after Herbst therapy, a significant mandibular forward displacement was achieved, due to increased bone remodelling of the condyles and rami compared to a comparison group. Three-dimensional changes in the direction and magnitude of condylar growth were observed in Herbst patients., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aim: To evaluate maxillary and mandibular dental arch changes induced by a passive self-ligating system by analysing digital dental casts., Subjects and Methods: A sample of 25 growing patients (16 females and 9 males, mean age 12.8 years) treated with passive self-ligating brackets was compared to a sample of 25 untreated controls (15 females and 10 males, mean age 13.4 years). Sixty three-dimensional points were digitised on the maxillary and mandibular pre- and post-treatment virtual models to evaluate differences in the transverse and antero-posterior arch dimensions and in the torque values of representative anterior and posterior teeth. Statistical comparisons were performed with independent sample t-tests with Holm-Bonferroni correction for multiple tests., Results: The greatest increments in arch widths were found at the maxillary and mandibular premolar level (ranging from 2.0 to 2.2mm) and they were associated with significant increases in maxillary and mandibular arch perimeters (2.3 and 2.5mm, respectively), and in buccal crown torque of the upper premolars (with adequate torque control of all other teeth)., Conclusions: The passive self-ligating system produced a modest but statistically significant widening of both maxillary and mandibular dental arches that were associated with significant net gains in maxillary and mandibular arch perimeters., (© The Author 2016. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Rapid maxillary expansion (RME) primarily involves the mechanical opening of the midpalatal suture of the maxillary and palatine bones. The fusion of the midpalatal suture determines the failure of RME, a common event in late adolescents and young adults. Recently, the assessment of the maturation of midpalatal suture as viewed using cone beam computed tomography (CBCT) has been introduced. Five maturational stages of the midpalatal suture have been presented: Stage A = straight high-density sutural line, with no or little interdigitation; Stage B = scalloped appearance of the high-density sutural line; Stage C = two parallel, scalloped, high-density lines that lie close to each other, separated in some areas by small low-density spaces; Stage D = fusion of the palatine bone where no evidence of a suture is present; and Stage E = complete fusion that extends also anteriorly in the maxilla. At Stage C, less skeletal response would be expected than at Stages A and B, as there are many bony bridges along the suture. For patients at Stages D and E, surgically assisted RME would be necessary, as the fusion of the midpalatal suture already has occurred either partially or totally. This diagnostic method can be used to estimate the prognosis of the RME, mainly for late adolescents and young adults for whom this procedure is unpredictable clinically.

The aim of this study was to determine the relationship between the closure stage of the spheno-occipital synchondrosis and the maturational stage of the cervical vertebrae (CVM) in growing and young adult subjects using cone beam computed tomography (CBCT). CBCT images with an extended field of view obtained from 315 participants (148 females and 167 males; mean age 15.6 ±7.3 years; range 6 to 23 years) were analyzed. The fusion status of the synchondrosis was determined using a five-stage scoring system; the vertebral maturational status was evaluated using a six-stage stratification (CVM method). Ordinal regression was used to study the ability of the synchondrosis stage to predict the vertebral maturation stage. Vertebrae and synchondrosis had a strong significant correlation (r = 0.89) that essential was similar for females (r = 0.88) and males (r = 0.89). CVM stage could be accurately predicted from synchondrosis stage by ordinal regression models. Prediction equations of the vertebral stage using synchondrosis stage, sex and biological age as predictors were developed. Thus this investigation demonstrated that the stage of spheno-occipital synchondrosis, as determined in CBCT images, is a reasonable indicator of growth maturation.

Objective: To evaluate the capability of both cervical vertebral maturation (CVM) stages 3 and 4 (CS3-4 interval) and the peak in standing height to identify the mandibular growth spurt throughout diagnostic reliability analysis., Materials and Methods: A previous longitudinal data set derived from 24 untreated growing subjects (15 females and nine males,) detailed elsewhere were reanalyzed. Mandibular growth was defined as annual increments in Condylion (Co)-Gnathion (Gn) (total mandibular length) and Co-Gonion Intersection (Goi) (ramus height) and their arithmetic mean (mean mandibular growth [mMG]). Subsequently, individual annual increments in standing height, Co-Gn, Co-Goi, and mMG were arranged according to annual age intervals, with the first and last intervals defined as 7-8 years and 15-16 years, respectively. An analysis was performed to establish the diagnostic reliability of the CS3-4 interval or the peak in standing height in the identification of the maximum individual increments of each Co-Gn, Co-Goi, and mMG measurement at each annual age interval., Results: CS3-4 and standing height peak show similar but variable accuracy across annual age intervals, registering values between 0.61 (standing height peak, Co-Gn) and 0.95 (standing height peak and CS3-4, mMG). Generally, satisfactory diagnostic reliability was seen when the mandibular growth spurt was identified on the basis of the Co-Goi and mMG increments., Conclusions: Both CVM interval CS3-4 and peak in standing height may be used in routine clinical practice to enhance efficiency of treatments requiring identification of the mandibular growth spurt.

Introduction: The aims of this study were to evaluate the differences between 2 regions of maxillary voxel-based registration and to test the reproducibility of the registration., Methods: Three-dimensional models were built for before-treatment (T1) and after-treatment (T2) based on cone-beam computed tomography images from 16 growing subjects. Landmarks were labeled in all T2 models of the maxilla, and voxel-based registrations were performed independently by 2 observers at 2 times using 2 reference regions. The first region, the maxillary region, included the maxillary bone clipped inferiorly at the dentoalveolar processes, superiorly at the plane passing through the right and left orbitale points, laterally at the zygomatic processes through the orbitale point, and posteriorly at a plane passing through the distal surface of the second molars. In the second region, the palate and infrazygomatic region had different posterior and anterior limits (at the plane passing through the distal aspects of the first molars and the canines, respectively). The differences between the registration regions were measured by comparing the distances between corresponding landmarks in the T2 registered models and comparing the corresponding x, y, and z coordinates from corresponding landmarks. Statistical analysis of the differences between the T2 surface models was performed by evaluating the means and standard deviations of the distances between landmarks and by testing the agreement between coordinates from corresponding landmarks (intraclass correlation coefficient and Bland-Altman method)., Results: The means of the differences between landmarks from the palate and infrazygomatic region to the maxillary region 3-dimensional surface models at T2 for all regions of reference, times of registrations, and observer combinations were smaller than 0.5 mm. The intraclass correlation coefficient and the Bland-Altman plots indicated adequate concordance., Conclusions: The 2 regions of regional maxillary registration showed similar results and adequate intraobserver and interobserver reproducibility values., (Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The aim of this study was to analyze the diagnostic performance of the cervical vertebral maturation (CVM) method in estimating accurately the stages of maturation of the midpalatal suture., Methods: Cone-beam computed tomography (CBCT) images from 142 subjects (84 female, 58 male; mean age, 14.8 ± 9.7 years) were analyzed by 2 calibrated examiners to define, by visual analysis, the maturational stages of the cervical vertebrae and the midpalatal suture. These CBCT images were required by orthodontists and surgeons for diagnosis and treatment purposes. Positive likelihood ratios (LHRs) were calculated to evaluate the diagnostic performance of the CVM stages in identifying the maturational stages of the midpalatal suture., Results: Positive LHRs greater than 10 were found for several cervical vertebral stages (CSs), including CS1 and CS2 for the identification of midpalatal suture stages A and B, CS3 for the diagnosis of midpalatal suture stage C, and CS5 for the assessment of midpalatal suture stages D and E. These positive LHRs indicated large and often conclusive increases in the likelihood that the CVM stages were associated with specific stages of midpalatal suture maturation. At CS4, there were a moderate positive LHR for stage C and low positive LHRs for stages D and E., Conclusions: Most CVM stages can be used for the diagnosis of the stages of maturation of the midpalatal suture, so that CBCT imaging may not be necessary in these patients. In the postpubertal period, however, an assessment of the midpalatal suture maturation using CBCT images may be indicated in deciding between conventional rapid maxillary expansion and surgically assisted rapid maxillary expansion. On the other hand, if the CVM stage cannot be assessed, chronologic age may be a viable alternative to predict some midpalatal suture stages (particularly the early stages)., (Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate the long-term effects of the standard (Class II) Balters bionator in growing patients with Class II malocclusion with mandibular retrusion by using morphometrics (thin-plate spline [TPS] analysis)., Materials and Methods: Twenty-three Class II patients (8 male, 15 female) were treated consecutively with the Balters bionator (bionator group). The sample was evaluated at T0, start of treatment; T1, end of bionator therapy; and T2, long-term observation (including fixed appliances). Mean age at the start of treatment was 10 years 2 months (T0); at posttreatment, 12 years 3 months (T1); and at long-term follow-up, 18 years 2 months (T2). The control group consisted of 22 subjects (11 male, 11 female) with untreated Class II malocclusion. Lateral cephalograms were analyzed at the three time points for all groups. TPS analysis evaluated statistical differences (permutation tests) in the craniofacial shape and size between the bionator and control groups., Results: TPS analysis showed that treatment with the bionator is able to produce favorable mandibular shape changes (forward and downward displacement) that contribute significantly to the correction of the Class II dentoskeletal imbalance. These results are maintained at a long-term observation after completion of growth. The control group showed no statistically significant differences in the correction of Class II malocclusion., Conclusions: This study suggests that bionator treatment of Class II malocclusion produces favorable results over the long term with a combination of skeletal and dentoalveolar shape changes.