Clear aligner treatment assisted by mini screw for an adult with Class II division 2 malocclusion and a right upper canine completely outside of the dental arch: A case report

This case report describes a 19-year-old man presented with a 5.7-mm deep overbite, Class II division 2 malocclusion with the right upper maxillary canine completely buccal ectopia, deviated midline in the upper arch, severe crowding and retroclination of the maxillary and mandibular incisors. The patient was treated with clear aligners to correct the Class II relationship and the deep overbite. A series of clear aligners were used to move bilateral maxillary molars distally with unilateral mini-screw anchorage. The final results showed that clear aligners with mini-screws could effectively achieve the required upper distal molar movement thanks to a reasonable design of the stages and anchorage. The treatment was completed in 19 months and the patient was satisfied with the treatment outcome in this context of mild to moderate Class II division 2 malocclusion.

Thirteen-year-old female patient with class II division 2 and normodivergent mandibular retrognathia treated with a fixed buccal appliance. Clinical case No. 221052, Commission of Titularisation. European College of Orthodontics

Date of birth>09/06/2004; sex: female. Pre-treatment documents>13years 4months old: 07/07/2017. Diagnosis>Skeletal class II with mandibular retrusion, normodivergent facial pattern; class II division 2. Treatment planning>bimaxillary buccal fixed appliance. Duration of active treatment>29months. Post-treatment documents>15years 6months; 20/12/2019. Post-retention documents>16years 7months old; 04/01/2021. Retention period>2years 9months and still continued.

Torque recovery of the maxillary incisors with a modified double J retractor in a Class II division 2 case treated with clear aligners

A patient with a Class II division 2 malocclusion is presented, illustrating the application of a modified double J retractor (DJR) and palatal miniscrews along with clear aligners to correct the malocclusion and normalize the incisor torque. In terms of incisor torque recovery, a nonextraction approach might be a good choice if the Class II correction could be successfully achieved with total arch distalization. When maxillary molar distalization was limited by anatomical boundaries, the treatment plan was changed to bilateral maxillary first premolar extractions, which led to even more retroclination of the maxillary incisors after space closure. Anterior interdental miniscrews were used to intrude the maxillary incisors. A modified DJR and palatal miniscrews were used to regain torque and achieve palatal root movement of the maxillary incisors. The treatment effects and biomechanical designs were evaluated for torque recovery of the retroclined maxillary incisors.

Comparison of the collum angle of incisors and canines in skeletal malocclusions - A CBCT study

INTRODUCTION

The collum angle that defines the crown root angulation of the single rooted teeth plays an important in treatment planning.

OBJECTIVE

To compare the collum angle (crown root angulation) of maxillary and mandibular anterior teeth in different skeletal malocclusions using Cone Beam Computed Tomography (CBCT).

MATERIALS AND METHODS

Sixty subjects were categorized into four groups (fifteen subjects in each group) Class I, Class II division 1, Class II division 2 malocclusion and Class III based on Angle classification, Wits and ANB. The collum angle of maxillary and mandibular anterior teeth was measured using CBCT. One way ANOVA, Post hoc comparison with Tukey HSD and Paired t-test were used to analyse the measured data.

RESULTS

The collum angle of corresponding right and left side teeth were averaged. Thus, the mean and standard deviation of the collum angle (n-30) were generated for maxillary and mandibular central incisors, lateral incisors, and canines. A statistically significant increase was observed in the maxillary central incisors of Class II division 2 and mandibular lateral incisors of class III malocclusion. The collum angle was increased in mandibular canines of Class III malocclusion when compared with class I and Class II division 2 malocclusion. The collum angle was negative in mandibular central incisors of Class II division 2. No statistically significant difference was observed in the mean collum angle between the right and left side anterior teeth in all the four groups.

CONCLUSION

A variation in Collum angle was observed between the maxillary and mandibular anterior teeth and malocclusions. The effect of these variations in collum angle in torque expression and biomechanics should be kept in mind by the orthodontist before treatment planning especially in Class II division 2 malocclusion.

Changes in lips, cheeks and tongue pressures after upper incisor protrusion in Class II division 2 malocclusion: a prospective study

Background

The etiology of Class II division 2 (CII/2) malocclusion focuses on heredity; however lip, cheek, and tongue pressures that are associated with the environmental effect are considered to have an effect. The aim of this study was to evaluate the relation between perioral pressures and the upper incisor inclination in CII/2 malocclusion.

Methods

Twenty patients (8 females, 12 males; mean age 10.29 ± 0.90 years) with CII/2 malocclusion were included in the study group, and 15 patients (5 females, 10 males; mean age 10.56 ± 1.06 years) with Class I malocclusion were included. The upper incisors were protruded with a utility arch (0.016 × 0.022 in. blue elgiloy wire). Perioral pressure assessment was made with the Iowa Oral Pressure Instrument. Upper lip pressure, lower lip pressure, vertical lip pressure, left-right buccal pressures, swallowing, and maximum tongue pressures were measured. Repeated measure ANOVA was used to test the intragroup differences. Intergroup comparisons were made using two-way repeated measure ANOVA with Bonferroni correction. Relationships between the variables were analyzed using rank correlation (Spearman’s rho). The significance for all statistical tests was predetermined at p < 0.05.

Results

A significant change occurred in the upper lip pressure, lower lip pressure, and vertical lip pressure; however, significant difference was not found between the groups. Upper lip pressure increased significantly in both groups. In the CII/2 group, lower lip pressure increased after protrusion and decreased after retention, while vertical lip pressure decreased and then increased significantly. Left buccal pressure changes between the groups were not parallel. Right buccal pressure, swallowing, and maximum tongue pressure changes were not statistically significant. Statistically significant correlation was found between U1-NA (mm) and vertical lip pressure (r −0.467).

Conclusions

In the CII/2 group, upper lip pressure increased only in retention. Lower lip pressure increased and vertical lip pressure decreased after protrusion. Nevertheless, these changes did not remain stable after the retention period. The difference between groups was not statistically significant at the end of retention.

Botulinum toxin as a therapeutic agent to prevent relapse in deep bite patients

INTRODUCTION

The etiology of deep bite is multifactorial. One of the causes is increased muscular activity. This makes the treatment of deep bite malocclusions difficult and often results in relapse in many cases. In this work we compared patients with surgical orthognathic treatment only and surgical orthognathic treatment with additional injections of botulinum toxin after mandibular advancement for class II division 2 malocclusion.

MATERIAL AND METHODS

This is a prospective study. Adult patients were assessed pretreatment (T1), posttreatment (T2), and long-term after 1 year (T3). In total, 32 patients (mean age, 30.7 years; 23 women and 9 men) reached the study end point (T3); 24 patients were treated without botulinum toxin and 8 patients received preoperative injections of botulinum toxin.

RESULTS

Significant differences between both groups were observed, with a more stable result for the experimental group treated with botulinum toxin.

DISCUSSION

In a selective group of adult patients with a class II division II incisor relationship and with a class II skeletal base, botulinum toxin injections can effectively prevent relapse. This may present an alternative to a conventional myotomy.