Bone resorption under chin implants: The orthodontist's role in its diagnosis and management.

Alloplastic chin implants have been a valuable treatment modality for the correction of microgenia. Their use has provided satisfactory esthetic results by improving facial balance. However, bone resorption under these implants can occur. Case reports of 4 patients with the incidental radiographic finding of the presence of chin implants are presented. All 4 subjects had lateral cephalograms and panoramic x-rays taken as part of their orthodontic evaluation. One had a normal mandibular symphyseal contour, and 3 had bone resorption under the implants. One subject had severe resorption. In addition to panoramic and cephalometric x-rays, the subject with severe resorption also had magnetic resonance imaging and computerized tomography as part of the evaluation workup.

Comparison of Corticotomy and Micro-osteoperforation during Canine Retraction: A Split-Mouth Design.

OBJECTIVE: Compare the efficacy of the micro-osteoperforation (MOP) and corticotomy techniques in terms of maxillary canine retraction. METHODS: Thirteen patients (5 females, 8 males; mean age, 18.07 ± 6.74 years) with healthy permanent dentition and requiring the extraction of maxillary first premolars were included in a split-mouth randomized clinical trial. Those subjects with previous orthodontic or endodontic treatment of the canines were excluded. At least 3 months post-extraction, MOPs and corticotomies were performed distal to the canines. Mini-screws with closed-coil springs (150 g) were used for the canine retraction. Dental casts were made at baseline (T0) and 3 months post-intervention (T1). Trained and calibrated examiners measured the distances from the canines to the second premolars on both sides. A signed-rank sum test was used to compare the amount of canine retraction achieved in 3 months (T0-T1) on the 2 sides. RESULTS: Retraction (mm) at the incisal level was similar in the corticotomy (3.34 ± 1.01) and MOP patients (2.74 ± 1.10) (P = 0.11); furthermore, there were no differences in the degree of medial retraction between the corticotomy (2.56 ± 0.67) and MOP (2.27 ± 0.82) (P = 0.31) procedures. No adverse events were observed. CONCLUSION: There were not any clinically or statistically significant differences in retraction between the interventions. At 3 months, a MOP is as effective as a corticotomy in accelerating the rate of tooth movement.

Botulinum Toxin and Smile Design.

Smiles with excessive gingival display exceeding 3 mm are considered unattractive. Excessive muscular contraction of lip elevator muscles is the etiology in most cases, and other factors, such as excessive vertical dimension of the maxilla and altered passive dental eruption resulting in the presence of excessive gingival tissue, account for the etiologic factors in others. Botulinum toxin type A (BTX-A) blocks muscular contraction by inhibiting the release of acetylcholine in muscles' endplates. The author has proven BTX-A to be an effective treatment alternative for the correction of these conditions affecting smile esthetics. This article explains how this is accomplished.

Body dysmorphic disorder: a screening guide for orthodontists.

Body dysmorphic disorder is a psychiatric condition that affects about 2% of the population. The objective of this article was to create awareness among orthodontists of this disorder and offer guidelines for its detection. As clinicians providing cosmetic services, orthodontists are likely to have patients with body dysmorphic disorder requesting treatment.

Botulinum toxin type A (Botox) for the neuromuscular correction of excessive gingival display on smiling (gummy smile).

INTRODUCTION: Previously, botulinum toxin type A (BTX-A) (Botox; Allergan, Irvine, Calif) was shown to be effective in reducing excessive gingival display in 5 patients with gummy smiles. This study was conducted to determine whether the doses and the primary injection sites used in the pilot study for the correction of gummy smiles provide consistent, statistically significant, and esthetically pleasing results. METHODS: Thirty patients received BTX-A injections to reduce excessive gingival display. Gingival display was defined as the difference between the lower margin of the upper lip and the superior margin of the right incisor. Patients were followed at 2, 4, 8, 12, 16, 20, and 24 weeks postinjection, with changes documented by photographs and videos. At week 2, the patients rated the effects of BTX-A. A group of specialty clinicians also evaluated the effects of BTX-A. RESULTS: Preinjection gingival display averaged 5.2 +/- 1.4 mm in the 30 patients. At 2 weeks postinjection, mean gingival display had declined to 0.09 mm (+/- 1.06 mm) in 30 patients (t = 26.01, P <.00001). The average lip-drop at 2 weeks was 5.1 mm for 30 patients. Gingival display gradually increased from 2 weeks postinjection through 24 weeks, but, at 24 weeks, average gingival display had not returned to baseline values. Based on predictions from a third-order polynomial equation, the baseline average of 5.2 mm would not be reached until 30 to 32 weeks postinjection. Patients and specialty evaluators rated the effects of BTX-A as highly favorable. CONCLUSIONS: BTX-A injections for the neuromuscular correction of gummy smiles caused by hyperfunctional upper lip elevator muscles was effective and statistically superior to baseline smiles, although the effect is transitory.

Re: 'Treatment of gummy smile: Nasal septum dysplasia as etiologic factor and therapeutic target'.

An evaluation and commentary of a recently suggested technique for the correction of gummy smiles is presented. A comparison of long-term stability reported with other surgical techniques, is also performed. From the results reported, use of this technique could offer a treatment option for those affected with excessive gingival display on smiling (gummy smile).

Botulinum toxin type A in the treatment of excessive gingival display.

PURPOSE: One cause of excessive gingival display is the muscular capacity to raise the upper lip higher than average. Several surgical procedures have been reported to improve the condition, but surgery always involves risk and is costly. Botulinum toxin type A (BTX-A) (Botox; Allergan, Irvine, Calif) has been studied since the late 1970s for the treatment of several conditions associated with excessive muscle contraction or pain. This clinical pilot study was performed to determine whether BTX-A injections would reduce excessive gingival display. MATERIAL: Five subjects with excessive gingival display due to hyperfunctional upper lip elevator muscles were treated with BTX-A injections. RESULTS: This treatment modality was effective, producing esthetically acceptable smiles in these patients. The improvements lasted 3 to 6 months. CONCLUSIONS: Injection with BTX-A at preselected sites is a novel, cosmetically effective, minimally invasive alternative for the temporary improvement of gummy smiles caused by hyperfunctional upper lip elevator muscles.