Long-term skeletal effects of high-pull headgear followed by fixed appliances for the treatment of Class II malocclusions

Objectives:The long-term skeletal effects of Class II treatment in growing individuals using high-pull facebow headgear and fixed edgewise appliances have not been reported. The purpose of this study was to evaluate the long-term skeletal effects of treatment using high-pull headgear followed by fixed orthodontic appliances compared to an untreated control group.Materials and Methods:Changes in anteroposterior and vertical cephalometric measurements of 42 Class II subjects (n = 21, mean age = 10.7 years) before treatment, after headgear correction to Class I molar relationship, after treatment with fixed appliances, and after long-term retention (mean 4.1 years), were compared to similar changes in a matched control group (n = 21, mean age = 10.9 years) by multivariable linear regression models.Results:Compared to control, the study group displayed significant long-term horizontal restriction of A-point (SNA = −1.925°, P < .0001; FH-NA = −3.042°, P < .0001; linear measurement A-point to Vertical Reference = −3.859 mm, P < .0001) and reduction of the ANB angle (−1.767°, P < .0001), with no effect on mandibular horizontal growth or maxillary and mandibular vertical skeletal changes. A-point horizontal restriction and forward mandibular horizontal growth accompanied the study group correction to Class I molar, and these changes were stable long term.Conclusions:One phase treatment for Class II malocclusion with high-pull headgear followed by fixed orthodontic appliances resulted in correction to Class I molar through restriction of horizontal maxillary growth with continued horizontal mandibular growth and vertical skeletal changes unaffected. The anteroposterior molar correction and skeletal effects of this treatment were stable long term.     

Effectiveness of maxillary protraction using a hybrid hyrax-facemask combination: A controlled clinical study

Objective:To evaluate the treatment effects of a hybrid hyrax-facemask (FM) combination in growing Class III patients.Material and Methods:A sample of 16 prepubertal patients (mean age, 9.5 ± 1.6 years) was investigated by means of pre- and posttreatment cephalograms. The treatment comprised rapid palatal expansion with a hybrid hyrax, a bone- and toothborne device. Simultaneously, maxillary protraction using an FM was performed. Mean treatment duration was 5.8 ± 1.6 months. The treatment group was compared with a matched control group of 16 untreated Class III subjects. Statistical comparisons were performed with the Mann-Whitney U-test.Results:Significant improvement in skeletal sagittal values could be observed in the treatment group over controls: SNA: 2.4°, SNB: −1.7°, Co-Gn: −2.3 mm, Wits appraisal: 4.5 mm. Regarding vertical changes, maintenance of vertical growth was obtained as shown by a small nonsignificant increase of FMA and a small significant decrease of the Co-Go-Me angle.Conclusions:The hybrid hyrax-FM combination was found to be effective for orthopedic treatment in growing Class III patients in the short term. Favorable skeletal changes were observed both in the maxilla and in the mandible. No dentoalveolar compensations were found.     

Long-term evaluation of the molar movements following Pendulum and fixed appliances

Objective:To describe the molar movements and skeletal changes associated with Pendulum-fixed appliance treatment and the long-term postretention period.Subjects and Methods:The treatment sample consisted of 76 Class II patients, 35 males and 41 females. Lateral cephalograms were obtained at the start of treatment (T1); the end of distalization (T2); the end of orthodontic fixed appliance therapy (T3); and long-term observation (7 years 2 months later; T4). Mean age was 12 years 11 months at T1, 13 years 8 months at T2, 15 years 4 months at T3, and 22 years 5 months at T4. The average amount of Class II molar relationship was 3.1 mm, with a mean overjet of 5.9 mm at the beginning of treatment. A paired t-test was used to identify significant between-group differences between T2–T4 and T3–T4.Results:Distal molar movement was obtained during the distalization phase (T2), and more than half of the distalizing effect was maintained at the end of maxillary growth (T4). Most of the relapse occurred during fixed appliance therapy (T3), whereas no significant change was detected in the postretention period (T4). The molar relationship did not show any significant difference between T2 and T4. The vertical facial dimension increased during the distalization phase (T2) and fixed appliance therapy (T3) but returned to the initial values during the postretention period (T4).Conclusions:The Pendulum appliance induces significant dentoalveolar effects, which can be partially maintained during the long-term period. The Class I molar relationship does not change during completion of individual growth. Increase in vertical facial dimension represents a temporary effect.     

Evaluation of the splint-supported Forsus Fatigue Resistant Device in skeletal Class II growing subjects

ObjectivesTo evaluate the use of the Forsus Fatigue Resistant Device (FFRD), supported with bimaxillary splints, in treatment of skeletal Class II malocclusion.Materials and MethodsData from 46 skeletal Class II females who received either conventional Forsus alone (FFRD group) (15 patients, 12.54 ± 0.90 years), FFRD and bimaxillary splints (splint-FFRD group) (15 patients, 12.29 ± 0.82 years), or were untreated controls (16 subjects, 12.1 ± 0.9 years) were retrieved from previous clinical trials. FFRD was inserted onto the mandibular archwire in the FFRD group after leveling and alignment with multibracket appliances. In the splint-FFRD group, Forsus was inserted between fixed maxillary and mandibular splints. Treatment continued until reaching an edge-to-edge incisor relationship.ResultsBoth treatment groups failed to induce significant mandibular skeletal effects compared to the normal growth exhibited by untreated controls. The splint-FFRD group showed significant reduction of SNA (−0.88° ± 0.51°) and ANB (−1.36° ± 0.87°). The mandibular incisors showed significant proclination in the FFRD (9.17° ± 2.42°) and splint-FFRD groups (7.06° ± 3.34°).ConclusionsThe newly proposed splint-supported FFRD was equally effective as the conventional FFRD in treatment of Class II malocclusion with dento-alveolar changes and additional maxillary restricting effect. It has an additional advantage of immediate initiation of the Class II correction.     

Treatment and posttreatment effects induced by the Forsus appliance: A controlled clinical study

Objective:To evaluate treatment and posttreatment dentoskeletal effects induced by the Forsus device (FRD) in growing patients with Class II malocclusion in a retrospective controlled clinical study.Materials and Methods:Thirty-six Class II patients (mean [SD] age 12.3 [1.2] years) were treated consecutively with the FRD protocol and compared with a sample of 20 subjects with untreated Class II malocclusion (mean [SD] age 12.2 [0.9] years). Lateral cephalograms were taken at the beginning of treatment, at the end of comprehensive treatment (after 2.3 ± 0.4 years), and at a postretention period (after 2.3 ± 1.1 years from the end of comprehensive treatment). Statistical comparisons were carried out with the unpaired t-test and Benjamini-Hochberg correction (P < .05).Results:After comprehensive treatment, the FRD sample showed a significant restriction of the sagittal maxillary growth together with a significant correction in overjet, overbite, and molar relationship. During the overall observation interval, the FRD group exhibited no significant sagittal or vertical skeletal changes, while significant improvements were recorded in overjet (−3.8 mm), overbite (−1.5 mm), and molar relationship (+3.7 mm).Conclusion:The FRD protocol was effective in correcting Class II malocclusion mainly at the dentoalveolar level when evaluated 2 years after the end of comprehensive treatment.     

Short-term effects produced by rapid maxillary expansion and facemask therapy in Class III patients with different vertical skeletal relationships

Objective:To evaluate the dentoskeletal short-term effects of rapid maxillary expansion and facemask therapy (RME/FM) in a sample of Class III patients showing different vertical skeletal relationships.Materials and Methods:Seventy-nine patients (35 females and 44 males) having Class III malocclusion were consecutively treated using RME/FM therapy with application of the protraction force in a downward and forward direction and inclination of about 30° to the occlusal plane. All patients were evaluated at the beginning (T1; mean age, 7.7 years) and at the end (T2; mean age, 9.2 years) of orthopedic therapy and divided into three groups according to their vertical skeletal relationships: normal group (NG), hypodivergent group (HypoG), and hyperdivergent group (HyperG). Statistical comparisons between the three groups were performed on the starting forms (T1), the final forms (T2), and the treatment changes (T1–T2) using the ANOVA with Tukey''s post hoc tests.Results:Favorable modification in terms of maxillary advancement (changes in SNA ranging from 1.4° to 1.8°) and intermaxillary sagittal skeletal relationships (changes in Wits appraisal ranging from 2.5 mm to 3.5 mm) were recorded in all groups. The three groups showed no statistically significant differences in changes in either sagittal or vertical skeletal variables.Conclusions:The various vertical skeletal features do not influence the short-term outcomes of RME/FM therapy.     

Long-term skeletal and dental effects and treatment timing for functional appliances in Class II malocclusion

Objective:To analyze the long-term skeletal and dentoalveolar effects and to evaluate treatment timing of Class II treatment with functional appliances followed by fixed appliances.Materials and Methods:A group of 40 patients (22 females and 18 males) with Class II malocclusion consecutively treated either with a Bionator or an Activator followed by fixed appliances was compared with a control group of 20 subjects (9 females and 11 males) with untreated Class II malocclusion. Lateral cephalograms were available at the start of treatment (mean age 10 years), end of treatment with functional appliances (mean age 12 years), and long-term observation (mean age 18.6 years). The treated sample also was divided into two groups according to skeletal maturity. The early-treatment group was composed of 20 subjects (12 females and 8 males) treated before puberty, while the late-treatment group included 20 subjects (10 females and 10 males) treated at puberty. Statistical comparisons were performed with analysis of variance followed by Tukey''s post hoc tests.Results:Significant long-term mandibular changes (Co-Gn) in the treated group (3.6 mm over the controls) were associated with improvements in the skeletal sagittal intermaxillary relationship, overjet, and molar relationship (∼3.0–3.5 mm). Treatment during the pubertal peak was able to produce significantly greater increases in total mandibular length (4.3 mm) and mandibular ramus height (3.1 mm) associated with a significant advancement of the bony chin (3.9 mm) when compared with treatment before puberty.Conclusion:Treatment of Class II malocclusion with functional appliances appears to be more effective at puberty.     

Treatment effects of the Carriere® Motion 3D™ appliance for the correction of Class II malocclusion in adolescents

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.     

Bone-anchored maxillary protraction long-term outcomes in UCLP:: A case report

This case report presents a 12-year-old boy with unilateral complete cleft lip and palate and severe maxillary retrusion treated with bone-anchored maxillary protraction (BAMP) therapy followed by fixed appliances. The follow-up period extended until the end of growth. Initially, the patient demonstrated a Goslon 4 interarch relationship with an overjet of −3.5 mm and a Wits appraisal of −7.9 mm. Six months after the secondary alveolar bone graft, Bollard miniplates were fixed bilaterally at the infrazygomatic region in the maxilla and between the canines and lateral incisors in the mandible. Class III elastics were used bilaterally full time for 12 months. After treatment, the overjet increased 5.9 mm. Significant maxillary advancement (SNA +3.2°) and skeletal convexity improvement (NA-APo +12.4°) were observed. Retrusion of the anteroposterior position of the mandible was observed (SNB –2.1°). Comprehensive orthodontic treatment was performed after BAMP therapy with nighttime bone-anchored Class III elastics as active retention until the end of growth. Occlusion and facial esthetics were satisfactory at the end of orthodontic treatment and growth. Le Fort I surgery for maxillary advancement was not required. BAMP therapy demonstrated an adequate orthopedic outcome, preventing the need for orthognathic surgery in unilateral complete cleft lip and palate.     

Factors associated with long-term vertical skeletal changes induced by facemask therapy in patients with Class III malocclusion

Objectives:This study investigated the long-term vertical skeletal changes induced by facemask therapy in patients with Class III malocclusion and different vertical skeletal patterns.Materials and Methods:A total of 54 patients (20 boys and 34 girls; mean age, 7.7 ± 2.0 years) with Class III malocclusion who were successfully treated with facemask therapy were included in this study. Vertical skeletal changes (overbite depth indicator, angle between the Sella-Nasion (SN) plane and Gonion-Gnathion (GoGn) line, angle between the Frankfort horizontal (FH) plane and mandibular plane, gonial angle, and angle between the SN plane and palatal plane) were measured on lateral cephalograms from before treatment (T0) to after facemask therapy (T1) and from T0 to after retention (T2). Multivariate linear regression analysis was used to study the associations of the patients'' skeletal patterns with the short-term (T0–T1) and long-term (T0–T2) vertical skeletal changes as a result of facemask therapy.Results:The mean treatment period of facemask therapy (T0–T1) was 1.4 ± 0.6 years, and the mean retention period (T1–T2) was 6.9 ± 2.6 years. Age at T0 was significantly correlated with vertical skeletal changes from T0 to T1. Differences in the treatment results between sexes were not significant. The angle between point A-point B line and mandibular plane to mandibular plane angle at T0 and the angle between the FH plane and mandibular plane at T0 were significant predictors for short-term and long-term changes. Changes in the Sella-Nasion-point A from T0 to T1 and from T1 to T2 significantly affected vertical changes in the short term and long term, respectively.Conclusions:Vertical skeletal changes as a result of facemask therapy are significantly associated with severity of the skeletal Class III malocclusion and mandibular plane angulation before treatment and the amount of forward maxillary growth during the treatment and retention periods.     

The Class II Carriere Motion appliance:: A 3D CBCT evaluation of the effects on the dentition

ObjectivesTo determine three-dimensional treatment changes produced by the Class II Carriere Motion appliance (CMA) in Class II adolescent patients with Class I and Class II skeletal relationships.Materials and MethodsThe sample included 59 adolescents (16 boys and 43 girls) with unilateral or bilateral Class II molar and bilateral Class II canine relationship. They were divided into group 1 with skeletal Class I (N = 27; ANB 2.90° ± 1.40°; 13.30 ± 1.53 years) and group 2 with skeletal Class II (N = 32; ANB 6.06° ± 1.64°; 13.26 ± 1.76 years). Cone beam computed tomography images were traced with Invivo software pretreatment (T1) and post-CMA usage (T2). The treatment changes in 36 measurements were calculated in each group, and the changes in 16 measurements were compared between them.ResultsIn group 1 and 2, maxillary first molars underwent significant distal movement (1.92 mm ± 0.80 mm and 1.67 mm ± 1.56 mm, respectively) with distal tipping and rotation, maxillary canines underwent significant distal movement (2.34 mm ± 1.07 mm and 2.24 mm ± 1.91 mm, respectively) with distal tipping and rotation, and mandibular molars underwent significant mesial movement (–1.37 mm ± 1.23 mm and –2.51 mm ± 1.51 mm, respectively) with mesial tipping. Between the groups, there were significant differences in mandibular molar mesial movement and the U1-SN changes (P < .05).ConclusionsThe CMA corrected Class II malocclusion through distal tipping and rotational movement of maxillary canines and molars and corrected mesial tipping of mandibular molars. Significantly more mandibular molar mesial movement and maxillary incisor flaring were observed in patients with skeletal Class II.     

A prospective controlled evaluation of Class II division 1 malocclusions treated with fixed lingual mandibular growth modificator

Objective: To assess the net dentofacial effects of the fixed lingual mandibular growth modificator (FLMGM).Materials and Methods:The study sample comprised 38 patients with Class II/1 malocclusion and retrognathic mandible. All were in the pubertal growth spurt. Whereas FLMGM was applied to the treatment group (n  =  21, mean age  =  13.2 years), no treatment was performed on the control group (n  =  17, mean age  =  12.5 years). Skeletal and dentoalveolar changes were assessed on digital lateral cephalograms obtained at the beginning and end of the treatment/observation period of 8 months. Paired and independent t-tests were used to assess the differences within and between groups.Results:Maxillary growth was not affected by FLMGM treatment, which resulted in a significant overjet reduction of 4.1 mm, an increase in total mandibular length (Co-Gn) of 2.3 mm, chin advancement of 1.6°, and upper incisor retroclination of 4.0°. A reduction of 2.4° in ANB was largely due to an increase of 1.8° in SNB. Favorably, the lower incisors were obviously retroclined by 4.5°. The changes in the vertical skeletal relationships were negligible.Conclusion:FLMGM was effective in treating growing Class II/1 patients and produced favorable dentofacial effects, with the matched untreated sample showing minimal changes. Lower incisor retroclination was a benefit of FLMGM treatment.     

A randomized clinical trial comparing mandibular incisor proclination produced by fixed labial appliances and clear aligners

Objective:To compare the mandibular incisor proclination produced by fixed labial appliances and third generation clear aligners.Materials and Methods:Patients underwent a course of orthodontic treatment using either fixed labial appliances or clear aligners (Invisalign). Mandibular incisor proclination was measured by comparing pretreatment and near-end treatment lateral cephalograms. Eligibility criteria included adult patients with mild mandibular incisor crowding (<4 mm) and Class I skeletal bases (ANB, 1–4°). The main outcome was the cephalometric change in mandibular incisor inclination to the mandibular plane at the end of treatment. Eligible patients picking a sealed opaque envelope, which indicated their group allocation, was used to achieve randomization. Data was analyzed using a Welch two-sample t-test.Results:Forty-four patients (mean age, 26.4 ± 7.7 years) were randomized in a 1:1 ratio to either the fixed labial appliance or the clear aligner group. Baseline characteristics were similar for both groups: Fixed appliance mean crowding was 2.1 ± 1.3 mm vs clear aligner mean crowding, 2.5 ± 1.3 mm; pretreatment mean mandibular incisor inclination for the fixed appliance group was 90.8 ± 5.4° vs 91.6 ± 6.4° for the clear aligner group. Fixed appliances produced 5.3 ± 4.3° of mandibular incisor proclination. Clear aligners proclined the mandibular incisors by 3.4 ± 3.2°. The difference between the two groups was not statistically significant (P > .05).Conclusion:There was no difference in the amount of mandibular incisor proclination produced by clear aligners and fixed labial appliances in mild crowding cases.     

Dentofacial effects of two facemask therapies for maxillary protraction: Miniscrew implants versus rapid maxillary expanders

Objective:To compare the dentofacial effects of maxillary protraction with two facemask therapies in growing Class III patients: facemask in association with miniscrew implants (MSI/FM) and facemask with rapid maxillary expanders (RME/FM).Materials and Methods:Forty-three Chinese patients with Class III malocclusion and maxillary deficiency were randomly assigned to a MSI/FM sample of 20 patients and a RME/FM sample of 23 subjects. The changes in dentofacial cephalometric variables from the beginning (T1) to the end of treatment (T2) were compared with t-test for paired samples in both groups and for independent samples between the two groups.Results:No significant cephalometric differences were observed between the two groups in active treatment effects except for maxillary dental variables. However, significant favorable changes in both maxillary and mandibular skeletal components were noted in two groups after treatment. Sagittal measurements showed the maxilla was advanced, mandibular projection was reduced, and the relative sagittal intermaxillary discrepancy improved. Patients experienced additional unfavorable outcomes of clockwise rotation of the mandible as well as retroclination of the lower incisors. The soft tissue profile was improved remarkably in both groups. Proclination of the maxillary incisors and mesialization of the maxillary dentition were significantly different between the two groups. The increases in U1-SN, U1-VR, and U6-VR were 6.41°, 2.78 mm, and 1.24 mm less in the MSI/FM group than in the RME/FM group, respectively.Conclusions:Compared with the RME/FM therapy, the MSI/FM protocol using a smaller magnitude of protraction force improves skeletal relationships and soft tissue profile and reduces the undesired dentoalveolar effects.     

Influence of skeletal class in the morphology of cervical vertebrae: A study using cone beam computed tomography

Objectives:To quantify the prevalence of cervical vertebrae anomalies and to analyze any association between them and skeletal malocclusions or head posture positions in the same study.Materials and Methods:Two hundred forty patients who were attending the Department of Orthodontics of the University of Valencia for orthodontic treatment were selected and divided into three groups: skeletal Class I (control group, 0° <ANB < 4°), Class II (ANB ≥ 4°), and Class III (ANB ≤ 0°) according to ANB Steiner angle. The morphology of the first five cervical vertebrae was analyzed with cone beam computed tomography to identify any anomalies. Intra- and interobserver error methods were calculated.Results:Dehiscence and fusion of one unit (both 23.3%) and partial cleft (11.7%) were the most frequent anomalies, while occipitalization was the least common (3.3%). Dehiscence anomaly was observed when the control group was compared with Classes II and III and partial cleft anomaly when Class I was compared with Class III. Furthermore, NSBa and ss-N-sm/ANB angles were associated with partial cleft anomaly, while NSL/NL angle and extended head posture were associated with fusion anomaly.Conclusions:Fusion, dehiscence, and partial cleft were the most frequent cervical vertebrae anomalies. Dehiscence and partial cleft were found to present statistically significant differences between Class I and Classes II and III. Cervical vertebrae anomalies and head posture were associated with fusion.     

Treatment effects produced by the Twin-block appliance vs the Forsus Fatigue Resistant Device in growing Class II patients

Objective:To compare the dentoskeletal changes produced by the Twin-block appliance (TB) followed by fixed appliances vs the Forsus Fatigue Resistant Device (FRD) in combination with fixed appliances in growing patients having Class II division 1 malocclusion.Materials and Methods:Twenty-eight Class II patients (19 females and 9 males; mean age, 12.4 years) treated consecutively with the TB followed by fixed appliances were compared with a group of 36 patients (16 females and 20 males; mean age, 12.3 years) treated consecutively with the FRD in combination with fixed appliances and with a sample of 27 subjects having untreated Class II malocclusion (13 females and 14 males; mean age, 12.2 years). Mean observation interval was 2.3 years in all groups. Cephalometric changes were compared among the three groups by means of ANOVA and Tukey''s post hoc tests.Results:The FRD produced a significant restraint of the maxilla compared with the TB and control samples (SNA, −1.1° and −1.8°, respectively). The TB sample exhibited significantly greater mandibular advancement and greater increments in total mandibular length than either the FRD or control groups (SNB, 1.9° and 1.5°, respectively; and Co-Gn, 2.0 mm and 3.4 mm, respectively). The FRD produced a significantly greater amount of proclination of the mandibular incisors than what occurred with the TB or the control samples (2.9° and 5.6°, respectively).Conclusion:The TB appliance produced greater skeletal effects in terms of mandibular advancement and growth stimulation while the Forsus caused significant proclination of the mandibular incisors.     

Long-term results of surgically assisted maxillary protraction vs regular facemask

Objective:To evaluate the short- and long-term treatment results of rapid maxillary expansion (RME) and surgical assistance during maxillary protraction with a facemask (FM).Materials and Methods:This study was carried out in 28 patients (12 male, 16 female) with maxillary retrognathism, anterior crossbite, and Class III skeletal and dental malocclusion characteristics. Seventeen patients (9 male, 8 female) with mild maxillary retrognathism were treated by RME and FM. The other 11 patients (8 female, 3 male), who had moderate to severe maxillary retrognathism, were treated with surgically assisted FM treatment. Patients treated with RME and FM were recalled after 5.64 years, and the surgically assisted FM group was recalled after 6.08 years. Cephalometric films taken before treatment (T₀), right after maxillary protraction (T₁), and at recall (T₂) were used to evaluate and compare the results.Results:In the short term, good maxillary advancement and a shorter treatment period were achieved with surgically assisted FM therapy. However, in the long term, maxillary advancement and some soft tissue improvements were lost. On the other hand, in the RME and FM protraction group, maxillary advancement and soft tissue improvement were well maintained.Conclusion:In the short term, statistically significant maxillary advancement was achieved with surgically assisted maxillary protraction. However, in the long term, these sagittal changes were not stable, whereas RME and FM provided stability.     

Dental and skeletal effects after total arch distalization using modified C-palatal plate on hypo- and hyperdivergent Class II malocclusions in adolescents

ObjectivesTo compare the dental and skeletal treatment effects after total arch distalization using modified C-palatal plates (MCPPs) on adolescent patients with hypo- and hyperdivergent Class II malocclusion.Materials and MethodsThe study group included 40 patients with Class II malocclusion (18 boys and 22 girls, mean age = 12.2 ± 1.4 years) treated with MCPPs. Fixed orthodontic treatment started with the distalizing process in both groups. Participants were divided into hypo- or hyperdivergent groups based on their pretreatment Frankfort mandibular plane angle (FMA) ≤22° or ≥28°, respectively. Pre- and posttreatment lateral cephalograms were digitized, and 23 variables were measured and compared for both groups using paired and independent t-tests.ResultsThe hyper- and hypodivergent groups showed 2.7 mm and 4.3 mm of first molar crown distalizing movement, respectively (P < .001). The hypodivergent group had a slight 2.2° crown distal tipping of first molars compared with 0.3° in the hyperdivergent group. After distalization, the FMA increased 3.1° and 0.3°, in the hypodivergent and hyperdivergent groups, respectively (P < .001). SNA decreased in the hypodivergent group, while other skeletal variables presented no statistically significant differences in the changes between the groups.ConclusionsThe hypodivergent group showed more distal and tipping movement of the maxillary first molar and increased FMA than the hyperdivergent group. Therefore, clinicians must consider vertical facial types when distalizing molars using MCPPs in Class II nonextraction treatment.     

Effects of skeletally anchored Class II elastics: A pilot study and new approach for treating Class II malocclusion

Objective:To evaluate the skeletal, dentoalveolar, and soft tissue effects of skeletally anchored Class II elastics and compare them with a matched control group treated by a monobloc appliance for the correction of skeletal Class II malocclusion due to mandibular retrusion.Materials and Methods:Twelve patients (6 girls, 6 boys) were randomly divided into two groups. In the elastics group, six patients (12.9 ± 1.5 years of age; 3 boys, 3 girls) were treated with skeletally anchored Class II elastics. Two miniplates were placed bilaterally at the ramus of the mandible and the other two miniplates were placed at the aperture piriformis area of the maxilla. In the monobloc group (3 boys and 3 girls; mean age, 12.3 ± 1.6 years), patients used the monobloc appliance. The changes observed in each phase of treatment were evaluated using the Wilcoxon matched-pair sign test. Intergroup comparisons at the initial phase of treatment were analyzed by the Mann-Whitney U test.Results:There were statistically significant group differences in Co-Gn, B-VRL, U1-PP, U1-VRL, Ls-VRL, with significant increases in these parameters in the elastics group (P < .05). The mandibular incisors were protruded in the monobloc group (5.45 ± 1.23°), whereas they were retruded in the elastics group (−3.01 ± 1.66°; P < .01).Conclusions:The undesirable dentoalveolar effects of the monobloc appliance were eliminated by using miniplate anchorage. Favorable skeletal outcomes can be achieved by skeletal anchorage therapies which could be an alternative to treat skeletal Class II patients with mandibular deficiency.     

A cone-beam computed tomographic evaluation of alveolar bone dimensional changes and the periodontal limits of mandibular incisor advancement in skeletal Class II patients

ObjectivesTo evaluate the presence of dehiscences and changes in alveolar bone height and width in the area of the mandibular central incisors pre- and post-orthodontic treatment.Materials and MethodsIn 60 skeletal Class II patients, cone-beam computed tomographic (CBCT) images were obtained and the patients were divided into four groups based on the presence of dehiscences at pre- and post-orthodontic treatment. The alveolar bone height and width were measured on CBCT in cross section along the long axis of the teeth. Lateral cephalograms were analyzed.ResultsThe changes in L1-NB and IMPA appeared to be correlated with vertical bone loss and dehiscence. Alveolar bone height appeared to follow a segmented relationship with these two variables, with changes below a threshold (L1-NB = 0.71 mm, IMPA = 3.02°) having relatively minimal or no effect on bone loss but with changes beyond the threshold correlated with extensive bone loss. Similarly, increases in L1-NB or IMPA correlated with decreases in alveolar bone width (L1-NB: −0.25 mm/mm, IMPA: −0.07 mm/°) and increased the probability of developing dehiscences, with an estimated 50% probability of vertical bone loss at a L1-NB change of 2.00 mm or, equivalently, an IMPA change of 8.02° was estimated.ConclusionsWhen treating skeletal Class II patients, the limits of incisor proclination/protraction are less than previously thought. To prevent undesired periodontal outcomes, careful three-dimensional diagnosis is advisable. Furthermore, when excessive protrusion and/or proclination is planned, additional treatment modalities, including orthognathic surgery, tooth extraction, and corticotomy with bone graft, should be considered.