Surgery first with clear aligners for a Class II patient: Case report and literature review

Orthognathic surgery has undergone multiple modifications in timing approaches, among them, surgery first represents an approach that potentially reduces length of time and shows earlier results in facial changes, nevertheless, it has been used mostly to treat Class III skeletal anomalies. Also, fixed appliances orthodontics is the most common choice, however, recent literature shows clear aligners can achieve the same results. This paper presents a case of a 20-year-old female with a skeletal Class II treated with surgery first and clear aligners protocol, with a literature review of surgery first in Class II patients; evidencing that this approach can be suitable to achieve satisfactory and stable results, although larger patient samples are needed.

Three-dimensional changes after maxillary molar distalization with a miniscrew-anchored cantilever

OBJECTIVES

To evaluate the changes after maxillary molar distalization in Class II malocclusion using the miniscrew-anchored cantilever with an extension arm.

MATERIALS AND METHODS

The sample included 20 patients (9 male, 11 female; mean age 13.21 ± 1.54 years) with Class II malocclusion, treated with the miniscrew-anchored cantilever. Lateral cephalograms and dental models obtained before (T1) and after molar distalization (T2) were evaluated using Dolphin software and 3D Slicer. Superimposition of digital dental models using regions of interest on the palate was performed to evaluate three-dimensional displacement of maxillary teeth. Intragroup change comparisons were performed using dependent t-test and Wilcoxon test (P < 0.05).

RESULTS

The maxillary first molars were distalized to overcorrected Class I. The mean distalization time was 0.43 ± 0.13 years. Cephalometric analysis demonstrated significant distal movement of the maxillary first premolar (-1.21 mm, 95% confidence interval [CI]: -0.45, -1.96) and maxillary first (-3.38 mm, 95% CI: -2.88, -3.87) and second molars (-2.12 mm, 95% CI: -1.53, -2.71). Distal movements increased progressively from the incisors to the molars. The first molar showed small intrusion (-0.72 mm, 95% CI: 0.49, -1.34). In the digital model analysis, the first and second molars showed a crown distal rotation of 19.31° ± 5.71° and 10.17° ± 3.84°, respectively. The increase in maxillary intermolar distance, evaluated at the mesiobuccal cusps, was 2.63 ± 1.56 mm.

CONCLUSIONS

The miniscrew-anchored cantilever was effective for maxillary molar distalization. Sagittal, lateral, and vertical movements were observed for all maxillary teeth. Distal movement was progressively greater from anterior to posterior teeth.

Dental changes induced by a modified Herbst appliance followed by fixed appliances: A digital dental model analysis

BACKGROUND

Herbst therapy is an effective treatment for Class II malocclusions. However, the maintenance of the effects after fixed appliances treatment remains questionable. This retrospective study aimed to assess, using digital dental models, the sagittal and transverse dental arch changes in young patients during two Class II Division 1 treatment phases, first with modified Herbst appliance (HA) and then with fixed appliances.

METHODS

The treated group (TG) comprised 32 patients (17 boys, 15 girls; mean age, 12.85 ± 1.16 years) treated with HA and fixed appliances. The control group comprised 28 patients (13 boys, 15 girls; mean age, 12.21 ± 1.35 years) with untreated Class II malocclusions. Digital models were obtained immediately before and after HA therapy and after fixed appliances. Data were statistically analyzed.

RESULTS

Compared with the control group, the TG showed an increase in maxillary and mandibular arch perimeters and in intercanine and intermolar arch widths, a decrease in overjet and overbite, and an improvement in canine and molar relationships. In the time after HA therapy until the end of fixed appliances treatment, the TG showed a decrease in maxillary and mandibular arch perimeters, overjet, upper and lower intermolar widths; an increase in molar Class II relationship; and no changes in canine relationship, overbite, and upper and lower intercanine widths.

CONCLUSIONS

In this sample of patients treated with HA, on average, there was an improvement in the Class II relationship, which seemed to remain after fixed appliances. The transverse dental changes achieved in HA phase relapsed after treatment with fixed appliances.

Invisible treatment of an asymmetric adult class II malocclusion related to unilateral upper lateral incisor agenesis with a straight wire lingual appliance, mini-screw and premolar extraction: A case report

This case report describes a complex full-step class II malocclusion with unilateral upper lateral incisor agenesis in an adult patient treated with lingual straight-wire appliance and premolar extraction, with the two-fold aim of obtaining ideal occlusal relationship and smile aesthetic improvement. In view of this, it underlines how an appropriate treatment strategy, including extraction choice and anchorage control during space closure, is needed to achieve the planned results with a completely invisible lingual appliance combined with aesthetic veneers.

Dentoskeletal effects of the maxillary splint headgear in the early correction of Class II malocclusion]

Objective

To compare dentoskeletal changes produced by the maxillary splint headgear and cervical headgear appliance during the early phase of Class II treatment, specially the initial overjet and upper incisors position.

Subjects and methods

In this retrospective study, 28 Class II patients treated with the maxillary splint headgear (maxillary splint headgear or MSG, mean age 10.1 ± 1.9 years) and 28 Class II patients treated with cervical headgear (cervical headgear group or CHG, mean age 9.5 ± 1.9 years) were evaluated before and after treatment. Statistical comparisons between the two groups for cephalometric measurements at T1 and for T2-T1 changes were performed by means of independent sample t tests.

Results

The MSG showed a significantly greater reduction of the overjet in comparison to the CHG (-2.4 mm and -0.7 mm, respectively) and a significantly greater maxillary incisor uprighting (-1.8 mm and 0.4 mm, respectively). In the MSG, overjet correction was due mainly to mandibular advancement (3.5 mm), while the correction of molar relationship (3.9 mm) was 64% skeletal and 36% dentoalveolar. In the CHG, the overjet correction was also more skeletal, due to mandibular growth (1.8 mm), while correction of molar relationship (3.5 mm) was 63% dentoalveolar and 37% skeletal.

Conclusions

Both groups showed favorable skeletal mandibular changes, which was more significant in the MSG. Regarding tooth movement, the maxillary splint headgear was more effective in uprighting upper incisors and reducing the overjet than cervical headgear appliance.

Malocclusion characteristics amongst individuals with autism spectrum disorder: a systematic review and meta-analysis

Background

To estimate the prevalence of malocclusion in individuals with autism spectrum disorders (ASD) and to assess the relationship between ASD and malocclusion.

Methods

We searched electronic databases including PubMed, Scopus, Web of Science, Cochrane, Embase, SciELO LILACS, Proquest, OpenGrey and Google Scholar. There were no language or publication dates restrictions. Two researchers independently performed selection, data extraction and quality assessment. Quality assessment and risk of bias were evaluated through the Newcastle–Ottawa scale and ROBINS-E tool. Meta-analyses using random effect models were used to estimate pooled measures of prevalence of malocclusion characteristics in individuals with ASD and pooled odds ratio (OR) on the relationship between ASD and malocclusion characteristics. Subgroup meta-analyses were conducted according to children and adolescents, history of orthodontic treatment, and occurrence of other syndromes and medical conditions.

Results

Searching identified 5549 papers with 238 were selected for full assessment. Eighteen cross-sectional studies were included according to inclusion criteria. Of them, eleven studies were considered of moderate quality. A judgement of critical risk of bias occurred for thirteen studies. The most prevalent malocclusion characteristics in individuals with ASD were crowding (33%; 95% CI 22 to 44%) and increased maxillary overjet (39%; 95% CI 23 to 54%). Individuals with ASD had higher odds of Angle’s Class II (OR 1.92; 95% CI 1.36 to 2.72), Angle’s Class III (OR 2.33; 95% CI 1.29 to 4.23), open bite (OR 1.96; 95% CI 1.21 to 3.16), and increased maxillary overjet (OR 1.53; 95% CI 1.06 to 2.21) than individuals without ASD.

Conclusions

Angle’s Class II, Angle’s Class III, anterior open bite and increased maxillary overjet were more prevalent in individuals with ASD than those without ASD. Further high-quality studies are needed.

Mandibular symphysis dimensions in different sagittal and vertical skeletal relationships

Background

The aim of this cross-sectional study was to compare the dimensions of mandibular symphysis (MS) between gender and the different sagittal and vertical skeletal relationships.

Material and Methods

Pre-treatment records of orthodontic patients were divided according to gender, sagittal (Class I, II and III) and vertical (decreased, average and increased mandibular plane [MP] angle) skeletal relationships. Measurements of MS parameters were performed on lateral cephalograms using IMAGEJ software. Comparisons between MS parameters and gender and the different skeletal relationships was performed using multifactorial and one-way ANOVA, and independent sample t-tests.

Results

A total of 104 records (25 males and 79 females) fulfilled the inclusion criteria. Males had significantly greater MS surface area, dentoalveolar length, skeletal symphysis length, total symphysis length, vertical symphysis dimension and symphysis convexity (p < 0.05). Skeletal Class II patients had significantly greater dentoalveolar and skeletal symphysis lengths while Class III had greater chin length, vertical symphysis dimension and symphysis convexity (p < 0.05). Patients with decreased vertical dimension had greater skeletal symphysis length (p = 0.026) and those with an average vertical relationship had greater chin length (p < 0.001).

Conclusions

The morphology of the mandibular symphysis is affected by gender, sagittal and vertical skeletal patterns. Males had increased mandibular symphysis surface area and linear dimensions. Class II patients had greater dentoalveolar length. Chin length was greater in patients with an average MP angle.

Esthetic perception of facial profile changes in Class II patients treated with Herbst or Forsus appliances

OBJECTIVE

To evaluate the esthetic perceptions of orthodontists and laypersons for facial profile changes after orthodontic treatment using Herbst or Forsus appliances.

MATERIALS AND METHODS

Pre- and posttreatment facial profile contour images of 20 Class II patients treated with Herbst (group H; n = 10) and Forsus (group F; n = 10) appliances were analyzed by 30 orthodontists and 30 laypersons, who graded them from 1 (unattractive) to 10 (very attractive) using a visual analog scale. Two assessments were carried out with a 15 day-interval. In the first evaluation, 40 images were presented in a random sequence. In the second evaluation, initial and final facial profile images of each patient were randomly presented side by side. To compare groups in relation to treatment method, Mann-Whitney tests were used. To evaluate differences between time points, Wilcoxon tests were used.

RESULTS

In the first evaluation, there was a significant difference between initial and final images only for group H, for both laypersons (P = .017) and orthodontists (P = .037). There was also a significant difference between laypersons and orthodontists in their ratings of posttreatment Herbst appliance profiles (P = .028). There was no significant difference between initial and final facial profile images for group F and no significant differences between or within evaluator groups in their ratings of initial or final Forsus appliance profiles. In the second evaluation, there was a significant difference between appliance groups only for laypersons, who considered cases treated with the Herbst appliance more attractive than those treated with the Forsus (P = .031). Laypersons also considered Herbst profiles more attractive than did orthodontists (P = .047).

CONCLUSIONS

Class II malocclusion treatment using the Herbst appliance may produce a more esthetically improved facial profile silhouette compared with Forsus appliances. The magnitude of perceived changes may not be considered clinically relevant.

Dentoskeletal effects of the maxillary splint headgear in the early correction of Class II malocclusion

Background

To compare dentoskeletal changes produced by the maxillary splint headgear and cervical headgear appliance during the early phase of Class II treatment, specially the initial overjet and upper incisors position.

Subjects and methods

In this retrospective study, 28 Class II patients treated with the maxillary splint headgear (MSG, mean age 10.1 ± 1.9 years) and 28 Class II patients treated with cervical headgear (CHG, mean age 9.5 ± 1.9 years) were evaluated before and after treatment. Statistical comparisons between the two groups for cephalometric measurements at T1 and for T2-T1 changes were performed by means of independent sample t tests.

Results

The MSG showed a significantly greater reduction of the overjet in comparison to the CHG (− 2.4 mm and − 0.7 mm, respectively) and a significantly greater maxillary incisor uprighting (− 1.8 mm and 0.4 mm, respectively). In the MSG, overjet correction was due mainly to mandibular advancement (3.5 mm), while the correction of molar relationship (3.9 mm) was 64% skeletal and 36% dentoalveolar. In the CHG, the overjet correction was also more skeletal, due to mandibular growth (1.8 mm), while correction of molar relationship (3.5 mm) was 63% dentoalveolar and 37% skeletal.

Conclusions

Both groups showed favorable skeletal mandibular changes, which was more significant in the MSG. Regarding tooth movement, the maxillary splint headgear was more effective in uprighting upper incisors and reducing the overjet than cervical headgear appliance.

Comparison of the dentoskeletal and soft tissue changes with the cervical headgear and Jones Jig followed by fixed appliances in Class II malocclusion patients: A retrospective study

OBJECTIVE

To retrospectively compare the dentoskeletal and soft tissue changes of patients with Class II malocclusion treated with cervical headgear and Jones Jig appliances, followed by fixed appliances.

MATERIAL AND METHODS

The sample comprised 46 Class II malocclusion patients divided into two groups. Patients with Class II malocclusion based on the ANB angle and plaster model analyses, needing non-extraction orthodontic treatment, absence of mandibular crowding and no previous orthodontic treatment were eligible to be selected. Group 1 consisted of 25 patients treated with cervical headgear (CH) followed by fixed appliances for a mean period of 3.26 years and group 2 consisted of 21 patients treated with the Jones Jig (JJ) appliance for a mean of 4.29 years. Lateral cephalograms were evaluated at the beginning and at the end of orthodontic treatment. For intergroup comparisons, t and Mann-Whitney tests were performed.

RESULTS

The cervical headgear group produced significantly greater maxillary anterior displacement restriction (SNA; CH: -0.97°±1.33; JJ: 0.07°±1.73; P=0.025), apical base discrepancy improvement (ANB; CH: -1.52°±1.25; JJ: 0.36°±1.46; P=0.006), FMA reduction (CH: -0.78°±2.68; JJ: 1.07°±2.84; P=0.028) and distal mandibular molar angulation (Md6.PM; CH: 6.97°±3.66; JJ: 2.77°±6.87; P=0.013) than the Jones Jig group.

CONCLUSIONS

Both distalizers followed by fixed appliances were effective to correct Class II malocclusion. The cervical headgear group presented skeletal effects with less treatment time and there were no significant intergroup differences regarding soft tissue changes.

Evaluation of the Effect of Fixed Anterior Biteplane Treatment on Temporomandibular Joint in Patients with Deep Bite

OBJECTIVE

To investigate the effects of fixed anterior biteplane treatment on temporomandibular joint in deep bite patients.

METHODS

The sample comprised 17 Class II patients with deep bite and decreased lower anterior facial height. The average patient age was 9.9±0.9 years. Transcranial temporomandibular joint radiographs were obtained from the subjects before (T0) and after fixed anterior biteplane treatment (T1). Anterior joint space, posterior joint space, superior joint space, anteroposterior thickness of the condylar head, vertical height of the articular fossa, and the articular fossa slope were measured on temporomandibular joint radiographs to evaluate the position of the mandibular condyles in the glenoid fossa.

RESULTS

The average treatment duration was 8.5±2.1 months. Slope of the articular fossa, vertical height of the articular fossa, anteroposterior thickness of the condyle, posterior joint space, superior joint space, and anterior joint space showed no statistically significant difference between T0 and T1 (p>0.05).

CONCLUSION

Fixed anterior biteplane appliance treatment did not change the condyle fossa relationship in Class II deep bite patients at the time of appliance removal.

Comparison of treatment outcomes with crowned and banded mandibular anterior repositioning appliance (MARA) in Class II pubertal subjects: A retrospective cohort study

OBJECTIVE

To compare the skeletal and dentoalveolar changes in Angle Class II malocclusion subjects treated with the banded Mandibular Anterior Repositioning Appliance (Ba-MARA) and crowned MARA (Cr-MARA).

MATERIALS AND METHODS

This retrospective cohort study included 40 consecutively treated pubertal adolescents with Class II division 1 malocclusion who received full-fixed orthodontic appliances with a phase of orthopedic treatment using Ba-MARA (n=20) or Cr-MARA (n=20). The samples were compared with 20 untreated Class II controls obtained from the Michigan Growth Study. Lateral cephalograms were obtained pre-treatment (T1), post-MARA removal (T2), and post-full-fixed orthodontic treatment (T3).

RESULTS

After MARA removal (T2-T1), the total mandibular length increased only in the Cr-MARA group compared to controls (Co-Gn=5.4mm; post-hoc P=0.042). Overall dentoskeletal changes were less significant during the T3-T2 timepoint. After full-fixed orthodontic treatment (T3-T1), and after controlling for normal growth, both Ba- and Cr-MARA groups increased the total mandibular length by 3.1mm and 3.8mm respectively. Overjet decreased by 2.2mm in Ba-MARA and 2.9mm in Cr-MARA. The mandibular molars erupted and moved mesially in both treatment groups. The mandibular incisors proclined significantly in the Cr-MARA group in comparison to controls (IMPA=7.1^o, post-hoc P=0.002).

CONCLUSIONS

Both MARA designs were effective in correcting the malocclusion by a combination of small skeletal and dental changes. Although significant differences in dentoskeletal outcomes were observed between the MARA groups and the controls, the differences between the two MARA designs were small and did not achieve statistical/clinical significance.

Condyle-glenoid fossa relationship after Herbst appliance treatment during two stages of craniofacial skeletal maturation: A retrospective study

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.

Three-dimensional skeletal mandibular changes associated with Herbst appliance treatment

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.

Influence of pharyngeal airway respiration pressure on Class II mandibular retrusion in children: A computational fluid dynamics study of inspiration and expiration

OBJECTIVES

To examine the influence of negative pressure of the pharyngeal airway on mandibular retraction during inspiration in children with nasal obstruction using the computational fluid dynamics (CFD) method.

SETTING AND SAMPLE POPULATION

Sixty-two children were divided into Classes I, II (mandibular retrusion) and III (mandibular protrusion) malocclusion groups.

MATERIAL AND METHODS

Cone-beam computed tomography data were used to reconstruct three-dimensional shapes of the nasal and pharyngeal airways. Airflow pressure was simulated using CFD to calculate nasal resistance and pharyngeal airway pressure during inspiration and expiration.

RESULTS

Nasal resistance of the Class II group was significantly higher than that of the other two groups, and oropharyngeal airway inspiration pressure in the Class II (-247.64 Pa) group was larger than that in the Class I (-43.51 Pa) and Class III (-31.81 Pa) groups (P<.001). The oropharyngeal airway inspiration-expiration pressure difference in the Class II (-27.38 Pa) group was larger than that in the Class I (-5.17 Pa) and Class III (0.68 Pa) groups (P=.006).

CONCLUSION

Large negative inspiratory pharyngeal airway pressure due to nasal obstruction in children with Class II malocclusion may be related to their retrognathia.

Comparative tomographic study of the maxillary central incisor collum angle between Class I, Class II, division 1 and 2 patients

INTRODUCTION:

It has been reported that Class II, division 2 maxillary central incisors frequently demonstrate increased collum angles, which indicates an excessive palatal “bend” of the crown. However, evidence supporting such observation is mostly derived from radiographic studies.

OBJECTIVE:

The objective of this study was to evaluate and compare the collum angle of maxillary central incisors in Class I, Class II, division 1, and Class II, division 2 cases using cone-beam computed tomography.

MATERIALS AND METHODS:

Forty-eight consecutive orthodontic cases (16 Class I, 16 Class II, division 1, and 16 Class II, division 2 malocclusion) with cone-beam computed tomography as part of their initial diagnostic records were evaluated. Cross-sections including maxillary right and left central incisors were used to calculate the angulation between the crown and root long axes (collum angle). Comparisons between groups were performed using analysis of variance for multiple and post-hoc Tukey for paired analyses.

RESULTS:

Mean collum angle observed in Class II, division 2 cases was significantly larger (5.2 ± 1.3°) than the ones obtained for Class I (1.1 ± 4.2°) (P = 0.034) or Class II, division 1 cases (0.1 ± 0.7°) (P = 0.014).

CONCLUSIONS:

Our findings suggest that Class II, division 2 individuals demonstrate accentuated lingual inclination of the maxillary central incisor crown compared to the other types of malocclusion studied here. Such morphological feature indicates the need for better tooth movement planning, especially in regard to root palatal torqueing of the maxillary central incisors.

Changes consequent to maxillary molar distalization with the bone-anchored pendulum appliance

OBJECTIVES:

This retrospective study aimed to evaluate the dentoalveolar, skeletal, and soft tissue effects obtained with bone-anchored pendulum appliance in patients with Class II malocclusion.

MATERIALS AND METHODS:

A total of 18 patients (4 male, 14 female) at a mean pretreatment age of 14.0 years (+1.08) were enrolled in this study. All patients were treated with the bone-anchored pendulum appliance for an average duration of 4.8 months. Only the active distalization period was evaluated with predistalization and postdistalization lateral cephalograms. Skeletal, dentoalveolar, and soft tissue variables were obtained. Based on these variables, the treatment effects were evaluated with dependent t-test.

RESULTS:

Correction of Class II molar relationship resulted from distal movement of 3.45 mm and tipping of 11.24° of the first maxillary molars. The premolars were distalized accompanying the molars.

CONCLUSIONS:

The bone-anchored pendulum appliance proved to be an effective method for distalization of maxillary molars in cases that require maximum anchorage, avoiding reciprocal mesial movement of premolars and incisors.

Class II malocclusion treatment effects with Jones Jig and Distal Jet followed by fixed appliances

OBJECTIVES

To compare the skeletal, dentoalveolar, and soft tissue changes in Class II malocclusion patients treated with Jones Jig and Distal Jet distalizers followed by fixed appliances.

MATERIALS AND METHODS

The experimental groups comprised 45 Class II malocclusion subjects divided into two groups. Group 1 consisted of 25 patients treated with the Jones Jig, and group 2 consisted of 20 patients treated with the Distal Jet. Group 3 comprised 19 untreated Class II subjects. Cephalograms were analyzed before and after orthodontic treatment. For intergroup comparisons, one-way analysis of variance and post hoc Tukey tests were performed.

RESULTS

During treatment, the experimental groups exhibited significant increases in occlusal plane inclination and maxillary second molar mesial tipping. Additionally, the molar relationship improved and overjet decreased significantly in the experimental groups. The Jones Jig group showed greater mandibular incisor proclination and greater overbite reduction than the control group. No significant intergroup differences in nasolabial angle changes were found.

CONCLUSIONS

Treatment protocols using the Jones Jig and Distal Jet followed by fixed appliances were effective in correcting Class II malocclusion by means of dentoalveolar changes without significant skeletal and soft tissue changes. The experimental groups showed occlusal plane clockwise rotation and greater mesial tipping of maxillary second molars when compared to the untreated group.

Discomfort, expectations, and experiences during treatment of large overjet with Andresen Activator or Prefabricated Functional Appliance: a questionnaire survey

BACKGROUND

The purpose of this study was to investigate the amount of functional and social discomfort experienced after 1 and 6 months of appliance wear, comparing a slightly modified Andresen Activator (AA) and a Prefabricated Functional Appliance (PFA).

METHODS

Ninety-seven patients randomly selected by lottery in an AA (40 subjects), and a PFA (57 subjects) group, with an Angle Class II, Division 1 malocclusion, were eligible for the study. One month and 6 months after start of treatment, a questionnaire, addressing discomfort, perception of treatment need and outcome, was used.

RESULTS

The response rate was 69% after 1 month, and 45% after 6 months. The most common discomfort reported was the 'appliance falling out during sleep' followed by 'difficulties in remembering it'. The only difference was for pain, which was experienced more extensively in the AA group after 1 month of treatment. The dentist appeared to have the greatest impact on the decision to initiate treatment. Teasing, because of appearance, occurred in 13% of the cases.

CONCLUSIONS

No difference could be seen between groups for the experience of functional or social discomfort after 6 months of appliance use. Adequate time should be allowed for clarifying treatment difficulties, using treatment need as motivation.

PRACTICAL IMPLICATIONS

The PFA eliminates the need for taking impressions. Furthermore, it can be economically advantageous to both patients and clinicians.

Rapid maxillary expansion effects in Class II malocclusion: a systematic review

OBJECTIVE

To evaluate the effectiveness of rapid maxillary expansion (RME) on the sagittal dental or skeletal parameters of growing children with Class II malocclusion.

MATERIALS AND METHODS

A systematic review intended to identify relevant literature was conducted. The search was performed on Medline, Embase, Cochrane Library, and Scopus databases. Reference lists of the included articles were also screened for relevant documents. The qualitative assessment was performed according to the Methodological Index for Non-Randomized Studies (MINORS) tool, and the resultant data were grouped and analyzed concerning dental and skeletal sagittal effects of RME.

RESULTS

Of 25 screened studies, seven articles met eligibility criteria and were included. Study samples were observed during mixed dentition stage and characterized as having either Class II dental malocclusion or skeletal discrepancy. None of the included studies was a randomized clinical trial. Included controlled studies presented several inadequacies related to control group or lacked appropriate comparative statistical analysis. Besides being frequently based on deficient methodology, dental and skeletal sagittal effects of RME were either controversial or lacked clinical relevance.

CONCLUSION

The effect of RME on the sagittal dimension of Class II malocclusions has not been proved yet. Future randomized controlled clinical trials are still needed to definitely address this question.

Effects of two different removable functional appliances on depth of the posterior airway space : A retrospective cephalometric study

OBJECTIVES

Aim of the study was the comparison of treatment effects upon pharyngeal depth in patients treated with either (1) S-II-appliance or (2) Activator.

METHODS

Pre- and posttreatment lateral cephalograms of 73 patients were analyzed using a customized set of measurements. According to predefined criteria, patients were either treated with S-II-appliance or Activator. Pharyngeal depth was assessed from cranial to caudal at six levels (P1 to P6). Paired t tests were used for intragroup and t tests for independent samples for intergroup comparisons. Results were considered statistically significant at p ≤ 0.05.

RESULTS

37 (22 female, 15 male) patients were treated with the S-II-appliance (mean pretreatment age 11.1 ± 1.07 years), and 36 (20 female, 16 male) patients with an Activator (mean pretreatment age 11.3 ± 1.12 years). Mean treatment time was 14 months for the S-II-appliance and 12 months for the Activator. Most measurements at the different levels showed an average increase ranging from approximately 0.5 mm to almost 2 mm. Changes were more pronounced in S-II patients. In contrast to intergroup comparisons, some intragroup comparisons revealed statistically significant differences at levels P5 (p = 0.0062) and P6 (p = 0.0155) in S-II patients and at P1-level (p = 0.0197) in Activator patients.

CONCLUSIONS

Both appliances similarly led to an increase of the pharyngeal depth. The sites of statistically significant changes differed.

Condylar resorptions and orthodontic-surgical treatment: State of the art

Resorption of the mandibular condyle [RMC] is a disease of the temporomandibular joints, with multifactorial origins. The clinical manifestations take the form essentially of joint pain and occlusal disorders, depending on the rate at which the condyle is affected. X-ray imaging shows that the condyle is reduced in volume, flattened and displaced backwards, with loss of cortical substance in advanced forms. The aim of this article is to recall some pathophysiological features and then to review all the diagnostic and etiological factors and discuss possible modes of management.

Comparison of stepwise vs single-step advancement with the Functional Mandibular Advancer in Class II division 1 treatment

OBJECTIVE

To compare two groups of subjects at the peak of the pubertal growth period treated with the Functional Mandibular Advancer (FMA; Forestadent, Pforzheim, Germany) appliance using either single-step or stepwise mandibular advancement.

MATERIALS AND METHODS

This study was conducted on 34 Class II division 1 malocclusion subjects at or just before the peak phase of pubertal growth as assessed by hand-wrist radiographs. Subjects were assigned to two groups of mandibular advancement, using matched randomization. Both groups were treated with the FMA. While the mandible was advanced to a super Class I molar relation in the single-step advancement group (SSG), patients in the stepwise mandibular advancement group (SWG) had a 4-mm initial bite advancement and subsequent 2-mm advancements at bimonthly intervals. The material consisted of lateral cephalograms taken before treatment and after 10 months of FMA treatment. Data were analyzed by means paired t-tests and an independent t-test.

RESULTS

There were statistically significant changes in SNB, Pg horizontal, ANB, Co-Gn, and Co-Go measurements in both groups (P < .001); these changes were greater in the SWG with the exception of Co-Go (P < .05). While significant differences were found in U1-SN, IMPA, L6 horizontal, overjet, and overbite appraisals in each group (P < .001), these changes were comparable (P > .05).

CONCLUSION

Because of the higher rates of sagittal mandibular skeletal changes, FMA using stepwise advancement of the mandible might be the appliance of choice for treating Class II division 1 malocclusions.

Rotation of the upper first molar in Class I, II, and III patients

OBJECTIVE

The aim of this study was to evaluate the mean rotation of the upper first molar (U1(st) M) in cast models from nontreated patients presenting: Class I, skeletal Class II, dental Class II, and skeletal Class III, comparing with Class I orthodontically treated patients.

MATERIALS AND METHODS

One hundred cast models were evaluated with five groups, composed of nontreated Class I (n = 20), dental Class II (n = 20), skeletal Class II (n = 20), skeletal Class III (n = 20), and treated Class I (n = 20). Measurements were taken from photocopies of the upper arches. The angle formed between a line crossing the mesiopalatal and the distal-buccalcusps of the U1(st) M and a line traced on mid palatal junction were measured in all samples.

RESULTS

One-way variance analysis showed that dental Class II group presented great mean rotation of the 1(st) molar (x = 78.95°, SD = 6.19) (P < 0.05), and in 85% of the patients from this group this angle was higher than 73°.

CONCLUSIONS

The skeletal Class II and skeletal Class III groups showed similar mean position of the 1(st) molar, presenting rotation in approximately 50% of the patients. It can be concluded that upper molar rotation occurs mainly in dental Class II patients and shows higher mesial rotation angle.

Cephalometric effects of the Jones Jig appliance followed by fixed appliances in Class II malocclusion treatment

Objective

The aim of this study was to cephalometrically assess the skeletal and dentoalveolar effects of Class II malocclusion treatment performed with the Jones Jig appliance followed by fixed appliances.

Methods

The sample comprised 25 patients with Class II malocclusion treated with the Jones Jig appliance followed by fixed appliances, at a mean initial age of 12.90 years old. The mean time of the entire orthodontic treatment was 3.89 years. The distalization phase lasted for 0.85 years, after which the fixed appliance was used for 3.04 years. Cephalograms were used at initial (T₁), post-distalization (T₂) and final phases of treatment (T₃). For intragroup comparison of the three phases evaluated, dependent ANOVA and Tukey tests were used.

Results

Jones Jig appliance did not interfere in the maxillary and mandibular component and did not change maxillomandibular relationship. Jones Jig appliance promoted distalization of first molars with anchorage loss, mesialization and significant extrusion of first and second premolars, as well as a significant increase in anterior face height at the end of treatment. The majority of adverse effects that occur during intraoral distalization are subsequently corrected during corrective mechanics. Buccal inclination and protrusion of mandibular incisors were identified. By the end of treatment, correction of overjet and overbite was observed.

Conclusions

Jones Jig appliance promoted distalization of first molars with anchorage loss represented by significant mesial movement and extrusion of first and second premolars, in addition to a significant increase in anterior face height.

Compensatory orthodontic treatment of Angle Class II malocclusion with posterior open bite

The present case report addresses the treatment of an Angle Class II malocclusion in an adult female patient, long face pattern, with posterior open bite and dental arches extremely expanded, due to previous treatment. The patient and parents rejection to a treatment with orthognathic surgery led to orthodontic camouflage of the skeletal discrepancies. This clinical case was presented to the Brazilian Board of Orthodontics and Facial Orthopedics (BBO) as one of the requirements to become a BBO Diplomate.