Unusual orthodontic retreatment

An unusual extraction pattern for retreatment in a patient with dental protrusion and a deficient soft-tissue chin

A patient with dental protrusion and deficient soft-tissue chin, previously treated with maxillary first premolar extraction, sought retreatment to improve his facial profile. Orthognathic surgery was proposed as the ideal treatment option, but the patient declined. Therefore, other orthodontic options were considered. The combined intrusion and retraction force systems supported with skeletal anchorage on both arches and a midpalatal miniscrew successfully reduced the protrusion and rotated the mandible counterclockwise to improve the facial profile and chin projection. Sagittal correction enhanced by active vertical control with skeletal anchorage and de-wedging with posterior extraction was illustrated. In addition, advancement genioplasty was performed after orthodontic treatment to improve the chin projection further. The mechanics and results of this retreatment case were discussed.

Effect of Class II camouflage treatment on anterior arch length ratio and canine relationship

INTRODUCTION

To evaluate the influence of compensatory tipping of maxillary and mandibular incisors on the anterior arch length ratio and canine relationship in skeletal Class II malocclusion.

METHODS

The study was based on posttreatment lateral head films and dental casts of 88 patients. The sample was divided into a Class II malocclusion group (32 patients; ANB ≥5° and mean [± standard deviation] age, 20.82 ± 7.67 years) and a Class I malocclusion group (56 patients; 1° ≤ ANB ≤ 2.5° and mean [± standard deviation] age, 19.20 ± 5.04 years). Measurements obtained for anterior arch length and width, Bolton discrepancy, canine relationship, growth pattern, and incisor position were compared between the groups. The canine relationship was correlated with dental and skeletal variables (P <0.05).

RESULTS

The mean ANB angles were 6.21° and 1.78° for the Class II and Class I malocclusion groups, respectively. The skeletal Class II group presented significantly larger mandibular anterior arch length, producing an unbalanced anterior arch length ratio. The canine relationship was more displaced toward Class II in this group. Anterior arch length ratio was the most influential variable in the canine relationship. The mandibular incisors had a higher compensation degree than the maxillary incisors. The groups were similar regarding overjet, overbite, and growth pattern.

CONCLUSIONS

Class II malocclusion camouflage treatment with excessive proclination of the mandibular incisors was associated with an increase in mandibular arch length, negatively influencing the anterior arch length ratio and the final canine relationship. Mandibular anterior arch length reduction by interproximal stripping may be necessary in moderate to severe skeletal Class II malocclusion orthodontic treatment.

Adult orthodontic retreatment of severe root resorption by skeletal anchorage: A case report

The presence of root resorption and its correlated factors are concerns that must be considered in orthodontic planning. This case report describes the orthodontic retreatment of a patient with a dental to facial midline discrepancy, a severe apical root resorption, and with maxillary and mandibular incisors presenting accentuated labial tipping and protrusion. The treatment included self-ligating brackets, maxillary unilateral distalization with skeletal anchorage and a mandibular extraction, followed by retraction. The orthodontic planning was based on simple and efficient mechanics and the treatment duration was of 19 months. Based on the acceptable final results it can be assumed that the treatment choices enabled a successful approach, maintaining a stable root condition.

Treatment times of Class II malocclusion: four premolar and non-extraction protocols

The purpose of this study was to retrospectively compare the treatment times of Class II division 1 malocclusion subjects treated with four first premolar extractions or a non-extraction protocol and fixed edgewise appliances. Eighty-four patients were selected and divided into two groups. Group 1, treated with four first premolar extractions, consisted of 48 patients (27 males and 21 females) with a mean age of 13.03 years and group 2, treated without extractions, consisted of 36 patients (18 males and 18 females) with a mean age of 13.13 years. Group 2 was subdivided into two subgroups, 2A consisting of 16 patients treated in one phase and 2B consisting of 20 patients treated in two phases. The initial and final Treatment Priority Index (TPI), initial ages, initial mandibular crowding, and treatment times of groups 1 and 2 were compared with t-tests. These variables were also compared between group 1 and the subgroups with analysis of variance followed by Tukey's tests. The treatment times for groups 1 and 2 and subgroups 2A and 2B were 2.36, 2.47, 2.25, and 2.64 years, respectively, which were not significantly different. Treatment times with non-extraction and four premolar extraction protocols are similar.

Orthodontic treatment time in 2- and 4-premolar-extraction protocols

INTRODUCTION

The purpose of this study was to compare the treatment times of complete Class II malocclusions treated with 2- and 4-premolar-extraction protocols.

METHODS

Ninety-seven patients were selected and divided into 2 groups, according to the 2 extraction criteria. Group 1, treated with 2 maxillary premolar extractions, consisted of 49 patients (30 male, 19 female) with a mean age of 14.35 years. Group 2, treated with 4 premolar extractions, consisted of 48 patients (27 male, 21 female) with a mean age of 13.03 years. Treatment times of the groups were compared with the t test.

RESULTS

Treatment times were significantly shorter with the 2-premolar-extraction protocol compared with the 4-premolar-extraction protocol.

CONCLUSIONS

Treatment time will be shorter and the occlusal results more predictable with a 2-premolar-extraction protocol compared with 4 premolar extractions.

Extreme dentoalveolar compensation in the treatment of Class III malocclusion

The orthodontic treatment of an adult patient with a skeletal Class III malocclusion, increased anterior facial height, negative overjet, and bilateral posterior crossbite is presented. Treatment options included mandibular first premolar or third molar extractions with dentoalveolar compensation or combined surgical-orthodontic treatment. Mandibular third molar extraction with dentoalveolar compensation was the treatment choice. Biofunctional brackets, with accentuated lingual crown torque on the maxillary incisors and accentuated buccal crown torque on the mandibular incisors, were used. The anterior crossbite was corrected with intermaxillary elastics from the palatal aspect of the maxillary incisors to the labial aspect of the mandibular incisors. Class III elastics moved the maxillary teeth mesially and assisted in retruding the mandibular teeth. Patient compliance with the elastics was excellent, and satisfactory dentofacial esthetics were achieved. This treatment protocol has rigorous indications, and it is not a routine plan. The mechanotherapy and the pros and cons of this approach are discussed.