Mandibular Protraction Appliance Effects in Class II Malocclusion in Children, Adolescents and Young Adults

Treatment of Mandibular Impacted Canine in a Patient with Class II Division 1 Malocclusion with "Reverse Pin": A Case Report

This case report presents an orthodontic treatment conducted on a 13-year-old girl with bilateral Class II malocclusion and a mandibular impacted canine. The presence of an impacted tooth necessitates careful consideration of the timing of orthodontic treatment, the appropriate surgical procedure to expose the tooth, the specific orthodontic mechanics involved, and the potential problems that may arise, all of which depend on the type and location of the canine impaction in the jaw. The treatment plan included a surgical procedure to expose the impacted tooth and orthodontic traction to guide it into position. Correction of the Class II Division 1 malocclusion utilized a specialized technique called the "reverse pin", reducing vertical side effects. The revised version maintains clarity and key information about the case report and treatment.

Association between nonextraction clear aligner therapy and alveolar bone dehiscences and fenestrations in adults with mild-to-moderate crowding

INTRODUCTION

This study aimed to assess the association between nonextraction clear aligner therapy (CAT) and the presence of alveolar bone dehiscences (ABDs) and fenestrations (ABFs) in adults with mild-to-moderate crowding.

METHODS

Cone-beam computed tomography images from 29 adults were obtained before and immediately after nonextraction CAT. Total root lengths were evaluated in axial and cross-sectional slices. Linear measurement for dehiscence (LM-D) was defined as the distance between the alveolar crest to the cementoenamel junction of each root (critical point set at 2 mm). Linear measurement for fenestration (LM-F) was recorded when the defect involved only the apical one-third of a root (critical point set at 2.2 mm). Counts of ABDs/ABFs and magnitudes of LM-Ds/LM-Fs were recorded before and immediately after nonextraction CAT at buccal and lingual root surfaces. Binary logistic regression analyses and repeated measures analyses of variance were performed.

RESULTS

Counts of ABDs/ABFs and magnitudes of LM-Ds/LM-Fs increased at most jaw locations and root surfaces. Nonextraction CAT was associated with an increased presence of ABDs and ABFs. Nonextraction CAT was associated with a higher magnitude of LM-Ds but not LM-Fs.

CONCLUSIONS

Immediate posttreatment cone-beam computed tomography scans showed that nonextraction CAT is associated with increased ABDs and ABFs in adults with mild-to-moderate crowding.

Orthodontic Management of Skeletal Class II Malocclusion with the Invisalign Mandibular Advancement Feature Appliance: A Case Report and Review of the Literature

The treatment of Class II malocclusion due to mandibular retrognathia is one of the most common challenges met in orthodontic practice. When it comes to a growing patient, functional appliances are the optimal way to achieve growth modification by enhancing mandibular growth. Clear aligners have been part of the orthodontic treatment for several decades but until recently they were only used to correct mild malocclusions. In 2017, Align Technology introduced the Invisalign with Mandibular Advancement Feature (IMAF) which replicates the action of functional appliances. As this device is new to clinical practice, there is limited literature on its clinical efficiency. This case report describes the orthodontic management of a 12-year-old male patient having skeletal Class II malocclusion due to mandibular retrognathia. As the patient was experiencing active growth, the IMAF appliance was chosen for his treatment. The IMAF appliance appears to be successful in the treatment of Class II malocclusion with mandibular retrognathism in a growing patient. As with all functional appliances, the correction of the malocclusion is a result of both skeletal and dental effects and the IMAF presents the advantage of producing less proclination of the lower incisors compared to other functional appliances.

Mandibular propulsion appliance for adults with Class II malocclusion: a systematic review and meta-analysis

BACKGROUND

The effects of mandibular propulsion appliances in adults have some controversial results. While some authors claim that its use in non-growing patients could produce some dentoskeletal effects, other studies indicate that Class II correction occurs only through significant dental effects.

OBJECTIVE

To evaluate the effects in non-growing Class II patients with mandibular retrusion, promoted by the treatment with mandibular propulsion appliances and determine if they produce mandibular changes.

METHODS

The research was carried out in nine electronic databases and additional manual searches up to July 2019. Selection criteria were no restriction was placed on date and publication language. Randomized or non-randomized clinical trials with/without control were included. They must evaluated non-growing patients with Class II malocclusion, treated with mandibular propulsion appliances; outcomes were assessed before and after treatment.

DATA COLLECTION AND ANALYSIS

Data were extracted by two independent examiners in duplicate. The ROBINS-I tool was used to assess the methodological quality of the included studies.

RESULTS

Of the 2824 articles identified, 11 non-randomized clinical articles were selected for qualitative analysis and 8 for quantitative analysis. SNB (0.87°, CI 95% 0.08, 1.66), ANB (-0.82°, CI 95% -1.24 to 0.40) and Pg/OLp [2.3 to 1.2 mm (P < 0.001)] presented smallest but significant mandibular changes with some differences regarding the used appliance. The Herbst appliance showed the largest mandibular changes followed by the SUS appliance when evaluated through Ar-Pg. SNA showed non-significant changes. Overbite (-2.85. CI 95% -3.06, -2.64), Overjet (-5.00.CI 95% -5.45, -4.55) showed significant changes in all devices. Class II correction occurs through a significant labial movement of the mandibular incisors, some lingual inclination of the maxillary incisors and minor skeletal changes.

CONCLUSIONS

All mandibular propulsion appliances examined, showed efficiency in normalizing the Class II malocclusion in adult patients; however, changes were acquired mainly through dentoalveolar changes. Some minor mandibular forward changes was noted, mainly in patients treated with the Herbst appliance. Randomized clinical trials are needed to improve scientific evidence.

REGISTRATION

PROSPERO (code CRD42017067384).

Comparative effects of the Mandibular Protraction Appliance in adolescents and adults

Objective:

The aim of this study was to compare the skeletal, dental, and soft tissue effects of the Mandibular Protraction Appliance (MPA) application in adolescent and adult Class II malocclusion patients.

Methods:

The sample comprised the pretreatment and posttreatment lateral cephalograms of 39 subjects presenting Class II malocclusion treated with the MPA and fixed appliances. Sample was divided into two groups: Group 1 comprised 23 subjects (10 male; 13 female), at a mean pretreatment age of 11.75 years, with a mean treatment time of 3.32 years; Group 2 included 16 subjects (7 male; 9 female), at a mean pretreatment age of 22.41 years, with a mean treatment time of 4.24 years. Intergroup comparison of the initial and final stages and treatment changes between the groups was performed with t tests, at p< 0.05.

Results:

The adults showed less significant amounts of skeletal, dentoalveolar and soft tissue changes than the adolescents. There was significantly greater palatal tipping of the maxillary incisors and retrusion of the upper lip in the adolescents. The adult group showed greater mandibular incisor proclination in the posttreatment stage.

Conclusion:

Adult patients treated with MPA showed less significant amounts of skeletal, dentoalveolar and soft tissue changes than adolescents.

Dentoskeletal and aesthetic effects of mandibular protraction appliance (MPA) using Ricketts analysis

Abstract Objective This study was designed to evaluate the skeletal, dental and soft tissue effects of mandibular deficiency treatment with the mandibular protraction appliance (MPA) using 12 factors of the Ricketts analysis. Material and method This cross-sectional retrospective study sample consisted of a group (n = 27), with Class II malocclusion, convex facial profile, increased horizontal trespass and mandibular deficiency, with initial mean age of 12.27 and final of 15.18 years, treated with fixed appliance combined with the MPA, in an average time of 2.9 years. Initial and final radiographs were investigated using Ricketts analysis. The dependent t-test was used to compare the initial and final phases of the MPA group, with a significance level of 5%. Result Statistically significant differences were observed for dental changes such as retrusion (p=0.000) and palatal inclination of the maxillary incisors (p=0.000); protrusion (p=0.000) and buccal inclination of the mandibular incisors (p=0.000); increased interincisal angle (p=0.002) and improved molar ratio (p=0.003). There was also a restriction of the anterior displacement of the maxilla (p=0.000) and a decrease in the mandibular plane angle (p=0.024). The variable inferior labial protrusion with significance (p=0.000), reiterated the improvement in the profile. Conclusion The effects of MPA on correction of malocclusion Class II, verified by Ricketts analysis occurred predominantly by dentoalveolar changes, decrease in the Mandibular Plane Angle, and restriction of anterior displacement of the maxilla, which contributed to the improvement in the patient's profile.

Perception, knowledge and attitudes of Brazilian orthodontists on the treatment of Class II malocclusions

The present study aimed to assess the perception and knowledge of Brazilian orthodontists on the ideal moment to treat Class II malocclusions. Questionnaires with open, semi-open and close questions were sent by e-mail to 1653 Brazilian orthodontists. These orthodontists were registered in the Brazilian Association of Orthodontics and Dentofacial Orthopedics (ABOR). One-hundred and three (9.86%) Orthodontists replied to the questionnaires. Most of them were males (60.5%) with specialization as the highest level of professional qualification (59.9%). Most of the orthodontists (51%) reported preference for treating Class II malocclusions in late mixed dentition, followed by the early mixed dentition (29%). The age range between 10 and 12 years old figured as the most prevalent in patients searching for treatment (42.7%). Most of the patients searching for treatment were females (69.7%). Preferences for functional orthopedic appliances were reported by 35% of the orthodontists. Brazilian orthodontists revealed a trend for treating patients with Class II malocclusions in the late mixed dentition. Female patients aged from 10 to 12 years old represented the majority of patients that search for orthodontic treatment. Functional orthopedic appliances were preferred by Brazilian orthodontists for treating Class II malocclusions.