The effect of morphine on orthodontic tooth movement in rats.

Objectives: To investigate the effect of morphine as an exogenous opioid on orthodontic tooth movement. Naltrexone will be used as an opioid antagonist to confirm the results.

Methods: Forty rats were randomly divided into four equal groups.

Comparison of occlusal balance contacts in patients treated with standard edgewise and preadjusted straight-wire appliances.

This study investigated the functional occlusion in two groups of patients treated to a Class I canine and molar relationship by fixed appliance therapy. Group A consisted of 24 patients treated with standard edgewise appliances, whereas the 15 patients in group B were treated with a straight-wire appliance. The occlusal contacts were assessed intraorally with articulating ribbon of 8 microns thick.

Comparison of wire loop and shear blade as the 2 most common methods for testing orthodontic shear bond strength.

Introduction: The purpose of this study was to compare 2 common methods of measuring orthodontic shear bond strength.

Methods: Brackets were bonded to 40 bovine incisors, and the teeth were mounted in a jig. The teeth were paired for symmetry, and the pairs were divided into 2 groups for debonding.

Introduction of a new orthodontic treatment planning software; a fuzzy logic expert system.

General practitioners can learn the mechanical aspects of orthodontics quickly. But they are not usually sure about the treament plans they propose. In this article, new software is described that proposes treatment plans fornon-surgical orthodontic cases.

Orthodontic treatment planning software.

A new software is described that can receive patient data in both graphic and numeric forms and then propose a treatment plan for nonsurgical orthodontic patients. The concepts of fuzzy logic enable the software to work with nominal parameters; the human brain is naturally accustomed to fuzzy variables. The computer program can propose treatment for some special cases, such as incomplete dentition.

Prediction of arch perimeter changes due to orthodontic treatment.

A borderline orthodontic case with mild to moderate space deficiency can be treated without extractions. Expansion can be used to relieve space deficiency. The prediction of arch perimeter change for a given amount of expansion is helpful in planning the treatment of a patient who needs expansion, and it can facilitate nonextraction orthodontic treatment.

Extrusion-based leveling with segmented arch mechanics.

Leveling of the dental arch may be accomplished through anterior intrusion, posterior extrusion, or a combination. Posterior extrusion is usually preferred in vertically balanced adolescents and in surgical-orthodontic treatment of adults suffering from deep bite and mandibular deficiency. A major disadvantage of posterior extrusion, when accomplished by continuous archwires, is incisor flaring.