Increase In Mandibular Length Research Articles

Pharyngeal airway and hyoid bone position changes of skeletal anchored Forsus Fatigue Resistant Device and activator appliances.

To evaluate the effects of miniplate anchored Forsus Fatigue Resistant Device (MAF) and activator treatments in the pharyngeal airway dimensions and hyoid bone position. Thirty-eight patients with mandibular retrusion who were treated with either MAF or activator were selected retrospectively and compared with an untreated control group. The data of 114 lateral cephalograms, comprising those taken before treatment (T1) and at the end of functional treatment (T2), were evaluated with regard to their linear, angular, and area measurements. The mandibular length increased and the hyoid bone moved forward with both treatments (P < 0.05). The horizontal change in the hyoid bone position with MAF treatment was correlated with changes in the point B and ANB angle. Increases of 1.8mm, 1.4mm, and 1.8mm in the pharyngeal airway dimensions were obtained at the levels of the second, third, and fourth cervical vertebra, respectively, with the MAF treatment. On the other hand, an increase of 1.9mm was found at the level of the fourth cervical vertebra with the activator treatment. The greatest vertical movement in the Menton and the highest increase in the oropharyngeal area were observed in the MAF group (P < 0.05). Both the MAF and activator treatments caused favorable maxillomandibular changes; however, the MAF treatment provided a greater increase in the oropharyngeal area according to both the increase in mandibular length and the change in the vertical position of the mandible. Functional appliances were found to be useful in increasing the pharyngeal airway dimensions in the short-term. The skeletal anchored fixed functional appliance caused a greater increase in the oropharyngeal airway area that may be beneficial for Class II patients who carry a risk of having respiratory problems.

Effects of fixed twin-block and forsus fatigue resistant device on mandibular third molar angulation – A comparative study

INTRODUCTION: Fixed functional appliances such as fixed twin-block (FTB) and forsus fatigue resistant device (FRD) improve Class II skeletal relationships by increasing the length of the mandible, which subsequently leads to an increase in the retromolar space. This would bring about a positional and angular change in the mandibular third molar. These appliances also produce forward movement of the mandibular buccal segments, which has also been cited as an important factor providing space and therefore improving the angulation and eruption potential of the third molars. OBJECTIVE: To evaluate and compare the effects of FTB and forsus FRD treatment on mandibular third molar angulation. MATERIALS AND METHODS: Pretreatment and posttreatment lateral cephalograms and orthopantomograms of 25 patients with Class II division 1 malocclusion treated with FTB were compared with those of 25 patients treated with forsus FRD. Sagittal and vertical skeletal relationships and mandibular length were assessed on lateral cephalogram, whereas linear parameters such as retromolar space; space width ratio (SWR); distance of Xi point from the distal surface of the lower second molar; and angular parameters such as α, β, and ϒ; and gonial angles were measured using orthopantomograms. Intragroup comparison was done using paired t-test, while unpaired t-test was done for intergroup comparison of the observed changes. RESULTS: Mandibular length increased significantly in the FTB group, whereas mesialization of the mandibular dentition was significantly high in the FRD group. Both groups showed a significant increase in retromolar space, SWR, Xi point to 7 distance, α angle, and a decrease in β angle. These changes were significantly more pronounced in the FTB group. CONCLUSION: There was a significant improvement in the third molar angulation following treatment with fixed functional appliances, which was comparatively more in the FTB group than that in the FRD group, owing to an increase in mandibular length.

Predicting mandibular growth based on CVM stage and gender and with chronological age as a curvilinear variable.

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. 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. 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. 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. 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.

Study of Functional Appliance for Treatments of Children and Adolescents with Class II Malocclusion

The purpose of this study was to evaluate the skeletal and dentoalveolar effects and optimal timing for treatment of class II malocclusion with functional appliances in children and adolescents.A group of 30 patients with class II malocclusion were divided into 3 groups according to their use of functional appliance: Twin block, Activator, Fränkel appliance. The group was also divided into 2 groups according to the cervical vertebrae maturation method. Lateral cephalometric radiographs were analyzed pretreatment (T0) and posttreatment (T1). Among the functional appliances, treatment with Twin block and Activator showed significant increase in the length of the mandible (Co-Gn) and the lower anterior facial height (ANS to Me), whereas the overjet and overbite were significantly reduced. Treatment with Fränkel appliance showed significant improvement in the relationship of maxilla and mandible. In addition, if the functional appliance was used during the period of pubertal growth peak, there was a significant increase in mandibular length, improvement in the relationship of maxilla and mandible, labial inclination of lower incisors and decrease in overjet compared to the treatment before pubertal growth peak. Therefore, this study indicates that using functional appliances for patients with class II malocclusion is effective and the optimal timing for using functional appliances is during pubertal growth peak.

Long-term effects of the Forsus Device in Class II division I patients treated at pre-peak, peak, and post-peak growth periods: A retrospective study

To assess the long-term effects of the Forsus Fatigue Resistant Device (FFRD) for the correction of Class II division 1 malocclusion during pre-peak, peak, and post-peak growth periods. This retrospective study was conducted on 60 patients that received FFRD with concurrent full-fixed orthodontic appliances during pre-peak (n=18), peak (n=21) and post-peak (n=21) maturational stages. The FFRD groups were compared with 60 untreated Class II control subjects obtained from the University of Michigan growth study and matched by skeletal age, sex, and observation periods. Lateral cephalograms were obtained at three time-points: [T1] pre-treatment; [T2] end of comprehensive orthodontic treatment; and [T3] retention (average of 3 years in retention). Nineteen linear and angular measurements were recorded. Short-term (T1- T2) and long-term (T1-T3) treatment changes were analyzed using paired Wilcoxon Signed Rank tests. In the pre-peak group, FFRD caused temporary restraint of maxillary growth and an increase in mandibular length at T1-T2 compared to controls. No significant differences were found at T2-T3 time points. The net changes (T1-T3) included a restraining effect on the maxilla and dentoalveolar compensation. In the peak group, maxillary restraint effect was seen at T1-T2, but this effect relapsed at T2-T3 time points. Similar to the pre-peak group, the net results (T1-T3) included maxillary headgear effect and dentoalveolar compensation. In the post-peak group, the net effects (T1-T3) of treatment included only dentoalveolar compensation. Overall, Class II malocclusion correction with FFRD is stable at three years post-treatment and is mainly achieved by maxillary restraint and dentoalveolar compensation at the pre-peak and peak stages and dentoalveolar compensation during the post-peak stage.

Therapeutic effectiveness of AdvanSync2 at different stages of skeletal maturity in skeletal Class II malocclusion: A single-blind clinical trial

Objectives: AdvanSync2 (Ormco, Glendora, California, USA) is a molar-to-molar fixed Class II corrector, based on the philosophy of Herbst which allows the bonding of the both upper and lower arches simultaneously along with fixed functional therapy. The purpose of this study was to cephalometrically compare the skeletal and dentoalveolar effects of AdvanSync2 in the correction of Class II malocclusions in circumpubertal and post-pubertal patients. Materials and Methods: Forty-eight samples were selected and divided into two groups based on their CVMI staging, Group A, i.e., at CVMI Stages 2 and 3 (18 girls and six boys) and Group B, i.e., CVMI Stages 4, 5, and 6 (19 girls and five boys). Cephalograms taken at pre- and post-AdvanSync2 stages were compared and analyzed. Results: The results showed that there was a significant increase in mandibular length in both groups. Both the groups also showed sagittal maxillary restriction, maxillary molar distalization, and retroclination of maxillary incisors. On comparison between Group A and Group B, there was no statistically significant differences in terms of maxillary position, size of maxilla, as well as upper and lower incisor inclinations in Group A except for improvement of mandibular position (SNB; P ≤ 0.01) and greater amount of chin growth (B -Pg; P ≤ 0.01) with respect to Group B. Conclusion: AdvanSync2 can be used as an effective fixed functional appliance in post-pubertal group for sagittal mandibular correction in skeletal Class II patients.

Dentoskeletal and soft-tissue changes comparison between the Jasper Jumper and Twin Force Bite Corrector in Class II malocclusion patients: A retrospective study

This retrospective study aimed to compare the dentoskeletal and soft-tissue changes in Class II malocclusion patients treated with Jasper Jumper and Twin Force Bite Corrector associated with fixed orthodontic appliances. The sample comprised 60 subjects divided into 3 groups. Patients with Class II malocclusion, mandibular retrusion, slight or no crowding and with no previous orthodontic treatment were eligible. Group 1 comprised 20 patients treated with the Jasper Jumper (JJ), with an initial age of 12.39 years. Group 2 comprised 20 patients treated with the Twin Force (TF), with an initial age of 11.83 years. The control group consisted of 20 untreated Class II subjects with an initial age of 12.13 years. Intergroup pretreatment comparisons were performed with One-way analysis of variance and intergroup treatment changes were compared with the Analysis of Covariance, both followed by Tukey test. The TF group showed greater increase in mandibular length (6.23mm±4.64, P=0.004) than the control group (2.94mm±1.75). The mandibular incisors in the experimental groups presented significantly greater labial inclination and protrusion than the control (Md1.NB; JJ: 4.19°±2.09; TF: 4.46°±6.83; control: 1.13°±2.08, P=0.000/Md1-NB; JJ: 1.95mm±1.45; TF: 1.74mm±1.79; control: 0.31mm±0.81, P=0.000). In addition, the treated groups also showed significantly improvement of the dental relationships (Overjet; JJ: -4.05mm±4.64; TF: -3.80mm±2.12; control: 0.05mm±1.12, P=0.000/Overbite; JJ: -2.52mm±1.46; TF: -2.93mm±2.13; control: -0.63mm±1.35, P=0.000). The Jasper Jumper and Twin Force associated to fixed appliances were effective in correcting Class II malocclusion with a combination of skeletal and dentoalveolar changes. However, the TF seems to provide more skeletal effects with greater maxillary growth restriction and mandibular length increase when compared to the JJ.

A multilevel analysis of craniofacial growth in subjects with untreated Class III malocclusion.

To analyse the craniofacial growth of a long-term semi-longitudinal sample of Caucasian subjects with untreated Class III malocclusion. A total of 144 Caucasian subjects (of North American and Italian origin) with untreated Class III malocclusion. Subjects aged 2years and 9months up to 21years and 7months were selected. A multilevel model was used to calculate growth curves for ten variables for both each individual subject and for the whole sample. There was a statistically significant increase for total mandibular length (Co-Gn. T2-T1=8.4mm), 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 3-5years of age and 11-15years of age) for seven out of ten variables. For Co-Gn and Co-A variables, males presented points of maximum growth delayed by 1year in comparison with females, with a greater duration (1year longer) and a greater total growth of about 5mm. Active mandibular growth continued for a long time after the pubertal spurt: increases in mandibular length ended at about 17years of age in females and at 21years and 7months in males. 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.

Three-dimensional comparison of the skeletal and dentoalveolar effects of the Herbst and Pendulum appliances followed by fixed appliances: A CBCT study.

To compare three-dimensional (3D) skeletal and dentoalveolar effects of the Herbst and Pendulum appliances followed by fixed orthodontic treatment in growing patients. A sample of 35 adolescents with cone-beam computed tomography scans obtained prior to Herbst and Pendulum treatment (T1) and immediately after fixed appliance treatment (T2). Patients with Class II malocclusion was assessed retrospectively and divided into two treatment groups: Herbst group (n=17, age: 12.0±1.6years) and Pendulum group (n=18, age: 12.1±1.5years), with a mean treatment duration of 2.8±0.8years and 2.5±0.7years, respectively. Reconstructions of the maxillomandibular and dentoalveolar regions and data in 3D were obtained relative to cranial base, maxillary and mandibular regional superimpositions. Treatment outcomes (T2-T1) were compared between both groups using t tests for independent samples (P<.05). Significant increase in mandibular length was observed in the Herbst group (7.3±3.5mm) relative to the Pendulum group (4.6±4.5mm). Inferior and anterior displacements of Pogonion were 2.2mm and 1.6mm greater in the Herbst group, respectively. The mesial displacement of the lower first molars was significantly greater in the Herbst group (1.9mm). The upper first molars had contrasting results in sagittal displacement, with 0.6±1.7mm of distal displacement with the Pendulum and 1.4±2.1mm of mesial displacement with the Herbst. Lower incisor projection and proclination were similar between groups. The Herbst and Pendulum appliances followed by comprehensive orthodontic treatment effectively corrected Class II malocclusion in growing patients, but with differing skeletal and dentoalveolar effects.

Influence of conventional and skeletal anchorage system supported fixed functional appliance on maxillo-mandibular complex and temporomandibular joint: A preliminary comparative cone beam computed tomography study

Fixed functional appliance (FFA) used in the treatment of Class II malocclusion, lead to mandibular anterior teeth proclination, thus limiting the skeletal effects of the appliance. To counter this side effect, FFA is anchored in the lower anterior region of the mandible using the skeletal anchorage system. This pilot study was done to evaluate treatment and one-year post-treatment maxillo-mandibular, and temporomandibular joint (TMJ) effects of conventional fixed functional appliance (FFA) and skeletal anchorage system supported fixed functional appliance (SAS-FFA) using cone beam computed tomography (CBCT) images. Sixteen Class II individuals were equally divided into Group I (FFA) (mean age 13.11±0.38 years) and Group II (SAS-FFA) (mean age 12.96±0.38 years). CBCT scans taken, before treatment (T0), at the end of comprehensive treatment (T1), and after one-year post-treatment (T2), were evaluated for changes in maxillo-mandibular complex and TMJ. Intraclass correlation coefficient and independent "t" test were used for repeated measures, and inter-group (mean) changes respectively. After one-year post-comprehensive treatment, SAS-FFA showed significant maxillary restriction (SNA, -1.93°, P<0.05) with significant increase in mandibular length (Go-Pog, 3.25mm, P<0.001) (Co-Gn, 7.87mm, P<0.001). SAS-FFA groups showed significant upward and backward increase in condylar volume (571 mm3, P<0.001) with anterior translation of glenoid fossa. FFA group showed significant lower dentition and vertical relationship relapse, along with non-significant changes at TMJ. SAS-FFA is an effective combination, which brings favourable changes on maxillo-mandibular complex and temporomandibular joint with non-significant relapse in comparison to FFA at one-year post-treatment.

Effects of articular disc or condylar cartilage resection on mandibular growth in young rats

ObjectiveThis study was aimed to compare the effects of articular disc and condylar cartilage resection on mandibular growth in Sprague Dawley rats. DesignEighty-four male Sprague Dawley rats (age = 4 weeks) were grouped according to the following procedures: group A (n = 21), exclusive surgical exposure of articular disc and condylar cartilage; group B (n = 21), exclusive surgical resection of articular disc; group C (n = 21), exclusive surgical resection of condylar cartilage; group D (n = 21), surgical resection of both articular disc and condylar cartilage. All surgery was performed in unilateral. One rat was killed in each group immediately after the surgery. Hematoxylin and eosin (H&E) staining was used to confirm the completely removal of the disc or cartilage. Five rats in the four groups were sacrificed in 1, 3, 6, and 9 weeks post-operation. The heights and lengths of the mandibles were measured and analyzed statistically. ResultsThe mandibular height of group D (5.01 ± 0.25 mm) was statistically lower than group A (5.59 ± 0.17 mm) at 1 week post-operation. The height of group C (5.62 ± 0.26 mm) was significantly lower than group A (6.27 ± 0.31 mm) 3 weeks after surgery. The height of group B (6.38 ± 0.36 mm) was significantly lower than group A (6.95 ± 0.10 mm) 6 weeks after surgery. At 9 weeks post-operation, the mandibular heights in groups B, C, and D were lower than group A, group D was lower than group C, and group C was lower than group B. The lengths of the mandibles were not significantly decreased until 9 weeks post-operation in group D. ConclusionsThe increase in mandibular height was interfered after either articular disc or condylar cartilage was resected, and mandibular height deficiency likely occurred earlier and more severely when cartilage was resected. However, the increase in mandibular length was barely interfered when either articular disc or condylar cartilage was resected.

Effect of removable functional appliances on mandibular length in patients with class II with retrognathism: systematic review and meta-analysis

BackgroundOrthopedic functional devices, are used to improve mandibular length in skeletal class II patients. However, the orthopedic functional device with the best effect to increasing the mandibular length, has not been identified before. Thus, the aim of the present investigation was to evaluate Randomized Controlled Trials (RCT), to determine the best functional appliance improving mandibular length in subjects with retrognathism.MethodsA systematic review and meta-analysis was performed, including studies published and indexed in databases between 1966 and 2016. RCTs evaluating functional appliances’ effects on mandibular length (Condilion-Gnation (Co-Gn) and Condilion-Pogonion (Co-Po)), were included. Reports’ structure was evaluated according to 2010 CONSORT guide. The outcome measure was distance between Co-Gn and/or Co-Po after treatment. Data were analyzed with Cochran Q Test and random effects model.ResultsFive studies were included in the meta-analysis. The overall difference in mandibular length was 1.53 mm (Confidence Interval (CI) 95% 1.15–1.92) in comparison to non-treated group. The Sander Bite Jumping reported the greatest increase in mandibular length (3.40 mm; CI 95% 1.69–5.11), followed by Twin Block, Bionator, Harvold Activator and Frankel devices.ConclusionsAll removable functional appliances, aiming to increase mandibular length, are useful. Sander Bite Jumping was observed to be the most effective device to improve the mandibular length.

Dentoskeletal and airway effects of the X-Bow applian ce versus removable functional appliances (Frankel-2 and Trainer) in prepubertal Class II division 1 malocclusion patients

Abstract Objectives The aim of the present study was to evaluate the dentoskeletal and airway effects of three different functional appliances (Frankel-2, Trainer and X-Bow) in prepubertal Class II division 1 patients. Methods The sample consisted of 54 patients with a Class II relationship as a result of mandibular retrognathia and relative maxillary constriction. Group I included 15 patients treated with a Frankel-2 appliance. Group II consisted of 14 patients treated with a T4-K Trainer. Group III consisted of 15 patients treated with the X-Bow appliance. Group IV consisted of 10 untreated Class II patients who served as a control group. Pretreatment (T1) and post-treatment (T2) cephalograms were used to evaluate dentoskeletal and airway changes. Parametric one-way variance analysis (ANOVA) and a paired t-test were used to perform statistical analysis. Results The decrease in SNA angle was significant in groups I and III, compared with the control group (p &lt; 0.05). SNB angle and Co-GN length changes from T1 to T2 were statistically significant in groups I and II (p &lt; 0.05), but not relative to the control group. The upper and lower incisors were significantly retruded and protruded, respectively, in all treatment groups (p &lt; 0.05). Except PNS-AD2 and MAS measurements in group I, nasopharyngeal and oropharyngeal airway dimensions did not significantly change from T1 to T2 in all groups. Conclusions The Frankel-2 and X-Bow appliances were efficient in restricting the forward growth of the maxilla. The Frankel-2 and Trainer appliances produced a larger sagittal increase in mandibular length than the X-Bow appliance. Lower incisor proclination was more pronounced in the X-Bow group. The effect of the treatment protocols was similar and matched the control group with respect to the airway.

The duration of pubertal growth peak among three skeletal classes.

ABSTRACTIntroduction: Pubertal growth peak is closely associated with a rapid increase in mandibular length and offers a wide range of therapeutic modifiability. Objective: The aim of the present study was to determine and compare the mean ages of onset and duration of pubertal growth peak among three skeletal classes. Methods: A retrospective cross-sectional study was conducted using lateral cephalograms of 230 subjects with growth potential (110 males, 120 females). Subjects were categorized into three classes (Class I = 81, Class II = 82, Class III = 67), according to the sagittal relationship established between the maxilla and the mandible. The cervical vertebral maturation stage was recorded by means of Baccetti's method. The mean ages at CS3 and CS4 and the CS3-CS4 age interval were compared between boys and girls and among three skeletal classes. Results: Pubertal growth peak occurred on average four months earlier in girls than boys (p = 0.050). The average duration of pubertal growth peak was 11 months in Class I, seven months in Class II and 17 months in Class III subjects. Interclass differences were highly significant (Cohen's d > 0.08). However, no significant difference was found in the timing of pubertal growth peak onset among three skeletal classes (p = 0.126 in boys, p = 0.262 in girls). Conclusions: Girls enter pubertal growth peak on average four months earlier than boys. Moreover, the duration of pubertal growth peak is on average four months shorter in Class II and six months longer in Class III subjects as compared to Class I subjects.

Numerical modeling of the traction process in the treatment for Pierre-Robin Sequence

IntroductionThe goal of this numerical study was to identify the results of modulated growth simulation of the mandibular bone during traction in Pierre-Robin Sequence (PRS) treatment. MethodsNumerical simulation was conducted in the Ansys 16.2 environment. Two FEM (finite elements method) models of a newborn's mandible (a spatial and a flat model) were developed. The procedure simulated a 20-week traction period. The adopted growth measure was mandibular length increase, defined as the distance between the Co-Pog anatomic points used in cephalometric analysis. ResultsThe simulation calculations conducted on the developed models showed that modulation had a significant influence on the pace of bone growth. In each of the analyzed cases, growth modulation resulted in an increase in pace. The largest value of increase was 6.91 mm. The modulated growth with the most beneficial load variant increased the basic value of the growth by as much as 24.6%, and growth with the least beneficial variant increased by 7.4%. ConclusionsTraction is a simple, minimally invasive and inexpensive procedure. The proposed algorithm may enable the development of a helpful forecasting tool, which could be of real use to doctors working on Pierre-Robin Sequence and other mandibular deformations in children.

Dentoskeletal effects produced by a Jasper Jumper with an anterior bite plane.

The aim of this retrospective study was to evaluate the dentoskeletal effects produced by a modified Jasper Jumper with an anterior bite plane for the correction of Class II division 1 malocclusion. A sample of 32 growing patients (mean age = 11.9 ± 1.4 years) with Class II division 1 malocclusion and increased overbite were treated with a modified Jasper Jumper (JJ) and anterior bite plane protocol and compared with a matched control group of 30 subjects with untreated Class II malocclusion (mean age 12.2 ± 0.8 years). Lateral cephalograms were taken before treatment (T1) and at the end of comprehensive treatment (T2). Mean treatment duration was 2.1 ± 0.4 years. The T1-T2 changes in the two groups were compared with Student's t-tests for independent samples. The JJ group was successfully treated to a Class I occlusal relationship with a significant reduction in overjet (-3.9 mm, P < .001) and overbite (-3.1 mm, P < .001). The JJ group exhibited a significant increase in mandibular length and a significant improvement in maxillomandibular sagittal skeletal relationships. The lower incisors were significantly proclined, while the lower first molars demonstrated significant movement in a mesial direction. Use of a modified JJ appliance and anterior bite plane is an effective protocol for the treatment of Class II malocclusion with increased overbite and greater skeletal (75%) than dentoalveolar (25%) effects mainly at the mandibular level.

The Herbst appliance and the Activator: influence of the vertical facial pattern

Abstract Aim To compare the effects of the Herbst appliance and the Activator at the completion of two-phase treatment, with respect to the vertical facial pattern (VFP) and to identify possible predictors of treatment effect. Materials and methods Pretreatment, post-treatment and overall cephalometric change data were used to assess the dental and skeletal effects. Results for the change in mandibular length were also compared with changes reported for an untreated external control group. Results Clinically significant dental and skeletal changes (including mandibular incisor proclination and overjet reduction) were characteristics of both treatment methods. Any increases in mandibular length and chin prominence were not greater than those expected following natural growth. The pretreatment VFP remained essentially unaltered, while mean changes as a result of treatment were similar for brachyfacial, mesofacial, and dolichofacial subjects. No predictive factors were identified. Conclusions Clinicians are advised to expect significant overjet reduction and mandibular incisor proclination with either treatment method. Significant skeletal change may be observed in growing subjects; however, any increase in mandibular length or chin projection is not likely to be beyond the limit set by nature. While there will be some individual variation, no significant long-term alteration in the pretreatment vertical facial pattern should be expected with either treatment. Long faces will remain long and short faces will remain short.

Dentoskeletal and Soft Tissue Effects in the Treatment of Class II Malocclusion with Klammt's Elastic Open Activator.

The purpose of this study was to evaluate the dentoskeletal and soft tissue effects resulting from treatment with Klammt's elastic open activator (EOA) functional orthopedic appliance in patients with Class II malocclusion characterized by mandibular deficiency. Teleradiographs were evaluated in the lateral aspect of the initial (T1) and final (T2) orthopedic phases for 16 patients with Class II, Division 1 malocclusion. The age range was from 9 to 11.2 years, with a mean age of 9.9 years. The cephalometric points were demarcated, and cephalometric measurements were obtained by the same investigator to avoid interobserver variability. The EOA promoted increased lower anterior facial height (LAFH), increased effective mandibular length, clockwise rotation of the mandible, retrusion and verticalization of the upper incisors, proclination and protrusion of the lower incisors, extrusion of the upper molars, mesial movement of the lower molars and anterior projection of the lower lip. Skeletal changes characterized by an increase in mandibular length and dentoalveolar changes with an emphasis on the verticalization and retrusion of the upper incisors, proclination of the lower incisors and mesial positioning of the lower molars were key to improving the occlusal relationship and esthetic facial factors. The EOA is well indicated in patients with Class II malocclusion due to mandibular deficiency with increased overbite, proclined upper incisors and verticalized lower incisors.

Effects of the Herbst appliance in growing orthodontic patients with different underlying vertical patterns

Abstract Introduction The present study involved an assessment of the effects of the Herbst appliance used for Class II correction in subjects with different vertical facial patterns. Methods Pre- and post-treatment lateral cephalograms of 91 growing Class II patients were divided into three vertical facial groups on the basis of mandibular plane angulation. All received a Herbst appliance and dental and skeletal changes were assessed in relation to pretreatment incisal overbite, overjet and the stage of cervical maturity. Results Herbst appliance treatment was accompanied by changes in the angulation of the upper and lower incisors, overjet reduction and an increase in mandibular length. In general, the rotational facial changes occurring during treatment were minimal, so that dolichofacial patterns remained long and brachyfacial patterns remained short. Conclusion Herbst appliance treatment can be expected to result in considerable Class II dental correction. It is unlikely, however, that its use will be associated with clinically significant forward rotation in dolichofacial subjects. Since dolichofacial patterns are likely to remain long-faced, even after considerable Class II dental correction, orthognathic surgery may still be a consideration if normal facial proportions, without excessive facial convexity and lip strain, are treatment aims.

Residents' journal review

Residents' journal review