New technique for creating permanent experimental alveolar clefts in a rabbit model.

Alveolar bone grafting is an adjunctive procedure that has become increasingly popular in the rehabilitation of patients with cleft lip and palate. A histologic basis of the performance of bone grafts is required to evaluate properly different grafting materials. This, however, cannot be provided by clinical studies on humans.

Arch length considerations due to the curve of Spee: a mathematical model.

Arch length analysis should consider discrepancies not only within the sagittal plane but also within the vertical and transverse planes. The vertical deviation of the occlusal plane from a flat plane is known as the curve of Spee. The purpose of this study was to produce a mathematical model of the mandibular arch form in three planes of space and to determine the effect that the curve of Spee has on arch circumference.

A comparison of the effects of first premolar extractions on third molar angulation.

The effect of third molars on the stability of orthodontic treatment has been studied extensively. Yet the effect of orthodontic treatment, particularly premolar extractions, on third molars has not been substantially studied. The purpose of this investigation was to compare the changes in third molar angulation in patients treated with and without extractions.

Increase in arch perimeter due to orthodontic expansion.

A mathematical model was developed to compare quantitatively the effects of various types of orthodontic expansion on mandibular arch perimeter. Mandibular arch form was modeled with spline interpolation to fit a smooth curve between assigned molar, canine, and incisor positions. Starting with average arch dimensions, intermolar width, intercanine width, and midline arch length were increased individually and in combination in millimeter increments up to 5 mm, and the consequent changes in arch perimeter were measured.

Tooth diameters and arch perimeters in a black and a white population.

This study was undertaken to test the hypothesis that a sample of black patients will have larger mesiodistal tooth diameters and larger dental arch perimeters than a corresponding sample of white patients. In this study, the black sample's mean canine, first and second premolar, and first molar mesiodistal diameters were significantly larger than those of the white sample. The dental arches of the black patients were significantly wider and deeper but did not show significantly more crowding.

Development of supernumerary premolars in an orthodontic population.

Seven cases exhibiting supernumerary premolar development were detected during a 2-year period during the routine care of approximately 1,100 orthodontic patients. This 0.64% prevalence is more than twice as high as has been previously reported and represents an occurrence rate of 1 per 157 patients.

Influence of vertical growth pattern on faciolingual inclinations and treatment mechanics.

Control of faciolingual tooth inclinations is obtained by using rectangular wire with third-order bends and standard edgewise brackets or by using a straight wire in a preadjusted appliance system. Ideal faciolingual inclinations have been determined previously by measuring facial surface contours relative to coronal long axes. This study evaluates faciolingual inclinations based on occlusal table inclinations relative to occlusal planes.

Frictional resistance of ceramic and stainless steel orthodontic brackets.

Frictional resistance of orthodontic appliances is recognized by most clinicians to be detrimental to tooth movement. The purpose of this study was to compare planar, static frictional forces among stainless steel and ceramic brackets. Both nitinol and stainless steel rectangular arch wires were passed freely through the slots of a pair of brackets from each type.

The morphology of canines in relation to preadjusted appliances.

The canine occupies the transition from anterior to posterior occlusion. Following orthodontic treatment the canine's incisal edge occlusion demonstrates the tip and torque present in the appliance that was used. The effective torque of the bracket, however, is influenced by the tooth morphology at the bracket's base.

Three biologic variables modifying faciolingual tooth angulation by straight-wire appliances.

The facial surface contours of 600 maxillary and mandibular teeth, including 50 of each type of tooth from central incisors to first molars, were measured. Facial contours present at the same location, facial contours from occlusal/incisal to gingival surfaces and the angle formed by the coronal and radicular long axes varied among teeth of the same type. The magnitude of the variation found was so great as to suggest that differences between patients or differences in height of bracket placement are greater than the differences between the standard torque prescriptions now used in orthodontics.

The effects of forceps delivery on facial growth.

Postnatal growth of the face is a composite function of genetic and environmental factors. A sudden traumatic insult due to the use of forceps at birth could have long-term effects which could detrimentally influence growth and development. This study examines the development of the skeletal and dental components of forceps vs.

3-Phenyl-5-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]indole-2-carbonitrile, a potent inhibitor of prostaglandin synthetase and of platelet aggregation.

A number of indoles containing the 2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl side chain have been prepared by standard methods. Alternate, novel syntheses of indole-2-carboxamides and indole-2-carbonitriles have been developed. The title compound, 7e, was found to be a potent inhibitor of bovine prostaglandin synthetase in vitro and to lower serum prostaglandin levels after oral or intraperitoneal administration to rats.