Prophylactic antibiotics recommended before orthognathic surgery. Some orthodontic patients require orthognathic surgery as part of their treatment plan. However, with any intraoral surgery, there is the risk for infection. Some surgeons prescribe antibiotics after surgery if an infection develops. Other surgeons recommend prophylactic antibiotics to reduce the risk of infection. Is there any evidence that prophylactic antibiotics are beneficial before orthognathic surgery? A study published in the Journal of Oral and Maxillofacial Surgery (1999;57:1403–1406) evaluated the effect of prophylactic antibiotics on the incidence of infection after orthognathic surgery. This was a randomized, double-blind, placebo-controlled clinical study. The

Abstract

The aim of this prospective longitudinal study of 62 consecutively treated Class II malocclusions was to determine whether bite-jumping causes temporomandibular disorders (TMD). The function of the temporomandibular joint (TMJ) was assessed anamnestically, clinically, and by means of magnetic resonance images (MRIs) taken before (T1), after (T2), and 1 year after (T3) Herbst treatment. Average treatment time with the Herbst appliance was 7.2 months. In all subjects, Herbst treatment resulted in a Class I or overcorrected Class I dental arch relationship. Thereafter, treatment was continued with a multibracket appliance. The condyle was positioned significantly forward during treatment but returned to its original position after removal of the Herbst appliance. A temporary capsulitis of the inferior stratum of the posterior attachment was induced during treatment. Over the entire observation period from before treatment to 1 year after treatment, bite-jumping with the Herbst appliance: (1) did not result in any muscular TMD; (2) reduced the prevalence of capsulitis and structural condylar bony changes; (3) did not induce disc displacement in subjects with a physiologic pretreatment disc position; (4) resulted in a stable repositioning of the disc in subjects with a pretreatment partial disc displacement with reduction; and (5) could not recapture the disc in subjects with a pretreatment total disc displacement with or without reduction. A pretreatment total disc displacement with or without reduction did not, however, seem to be a contraindication for Herbst treatment. In conclusion, bite-jumping using the Herbst appliance does not have a deleterious effect on TMJ function and does not induce TMD on a short-term basis.

Abstract

One of the most important components of orthodontic diagnosis is the evaluation of the patient's soft tissue profile. There have been many attempts to quantify the soft tissue profile based on the lateral cephalogram. Yet, the methodology used to evaluate the profile varies widely among studies, and there has been no consistency in the way straight lines are constructed in the analysis of the soft tissue contours. The purpose of the current study was to compare the values obtained by 2 drawing methods (tangent line and anatomic points) of constructing angles, and to assess the intraobserver and interobserver reproducibility for both methods. There were statistically significant differences between the 2 methods for 9 of the 10 measurements evaluated. In the comparison of reproducibility assessed by Pearson correlation analysis, both methods showed statistically significant correlations between repeated measurements. The anatomic point method, however, showed greater reproducibility by means of a paired t-test. In the analysis of intraobserver reproducibility, 2 measurements showed significant differences with the anatomic point method and 4 measurements demonstrated significant differences when the tangent line method was used. In the analysis of interobserver reproducibility, 5 measurements showed significant differences in the anatomic point method, while 6 measurements represented significant differences in the tangent line method. Our results indicate that a precise description of the methodology used in the analysis of the soft tissue must be provided because of the differences between methods. In the analysis of soft tissue contours, the construction of lines with the anatomic point method is more reproducible than the tangent line method.

Abstract

This study was undertaken to compare the post-treatment and long-term soft tissue profiles of successfully managed and stable Class II, division 1 malocclusions treated with either 4 first premolar extractions or nonextraction therapy. It was hypothesized that, if sound extraction decisions were made according to accepted treatment objectives and successful treatment outcomes were achieved, there should be no differences between groups in soft tissue profiles post-treatment and long-term post-retention. The sample consisted of 63 Caucasian adolescents (23 extraction, 40 nonextraction). Correction of the malocclusion was achieved using a combination of cervical headgear concurrent with mandibular growth and maxillary incisor retraction. Pretreatment, post-treatment, and long-term post-retention lateral cephalometric radiographs were evaluated. The soft tissue facial profiles of the extraction and nonextraction samples were the same following active treatment and long-term post-retention. Progressive flattening of the facial profile was observed in both samples. This flattening was attributed to the maturational changes associated with continued mandibular growth and nasal development and was not influenced by whether or not teeth were removed. Long-term lip positions were more retrusive than the ideals suggested by Ricketts and Steiner, but close to the values reported for normal, untreated adults of similar ages. The pretreatment position and thickness of the lower lip as well as the initial maxillomandibular skeletal relationship may be predictors of post-treatment or long-term lower lip position.

Breast-Feeding, Suckling and the Sucking Urge: Their Development and Their Influence on the Developing Dentition. Larsson, Erik. Bishara, S (ed). 1999, Sweden. 37 pages, $25.00. Available from the author: Tandregleringen, Kottorget 5, S52142, Falkoping, Sweden. (e-mail: Larsson.afzelius@mailbox.calvpso.net).

Dr Erik Larsson, Professor of Orthodontics at the University of Oslo, has written Breast-feeding, Suckling and the Sucking Urge, a short and fascinating book that provides extensive information about breast-feeding, thumb-sucking, pacifier use, and their influence on dental occlusion and facial growth.

Using an anthropologic approach, he reveals how attitudes have changed from unrestricted breast-feeding to highly limited feeding restricted

Lip incompetence resolved by active vertical control in nonsurgical treatment of a protrusion case with vertical maxillary excess

Johnny JL Liaw,

Jae Hyun Park,

Fang Fang Tsai,

Betty MY Tsai, and

Wendy WT Liao

Orthodontic Faculty—A Modest Proposal

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Does Bite-Jumping Damage the TMJ? A Prospective Longitudinal Clinical and MRI Study of Herbst Patients

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A Comparative Study of Two Methods of Quantifying the Soft Tissue Profile

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Long-Term Profile Changes Associated with Successfully Treated Extraction and Nonextraction Class II Division 1 Malocclusions

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Long-Term Prognosis of BSSO Mandibular Relapse and its Relation to Different Facial Types

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External Apical Root Resorption Following Orthodontic Treatment

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A Comparative Clinical Trial of a Compomer and a Resin Adhesive for Orthodontic Bonding

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The Influence of Orthodontic Adhesive Properties on the Quality of Orthodontic Attachment

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Case Report: Orthodontic and Dentofacial Orthopedic Considerations in Apert's Syndrome

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In Memoriam: J. Edward Gilda, DDS, MS

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Lip incompetence resolved by active vertical control in nonsurgical treatment of a protrusion case with vertical maxillary excess

Changes in glenoid fossa of adult female patients with Class II division 1 malocclusion during premolar extraction treatment and mini-implant anchorage: a cone-beam computed tomography study

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Miniscrew-assisted slow palatal expansion with bone borne expander in adult patients: a case control study on consecutively treated patients

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