A Study of Crown and Root Angulation on Maxillary First and Second Bicuspids

<p>Pre-adjusted bracket systems offer the clinician the convenience of working with both fewer in number and smaller in magnitude adjustments of an archwire. The purpose of this in vitro study was to examine the normal variations in crown angulation of individual maxillary bicuspids, in a simulated flat plane of occlusion, and how this relates to marginal ridge discrepancies. A second purpose of this study was to examine these same teeth for the angulations of the roots. Fifty maxillary first bicuspids and thirty eight second bicuspids from the Loma Linda University Dental School restorative dentistry department were, in a flat plane of occlusion, examined. These teeth, with respect to variation in angular measurements of the roots and crowns, were measured at the level of the marginal ridges. From these measurements, the data analysis calculated the mean and standard deviation for angulation, mean difference of measurements, a linear regression relating crown angulation to root angulation, and a millimeter measurement for marginal ridge discrepancy.</p> <p>Conclusions are presented showing the first maxillary bicuspid to have a mean negative crown angulation of 0.52 degrees, mean distal root tip of positive 8.08 degrees, and a marginal discrepancy of only 0.072mm. The second maxillary bicuspid exhibited mean measurements of 3.70 degrees of positive crown angulation, distal root tip of positive 3.68 degrees, and a marginal ridge discrepancy of 0.48mm.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Dentistry

Year

1993

Author dc:creator

• Chamberlain, Craig A.

Contributors dc:contributor

• James Farrage
• Joseph M. Caruso
• David Rynearson
• Craig Andreiko

• Orthodontics and Orthodontology
• Bicuspid; Orthodontics

Statement dc:rights

• This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Language dc:language

English

Repository record dc:identifier

https://scholarsrepository.llu.edu/etd/1228

OAI identifier oai:identifier

oai:scholarsrepository.llu.edu:etd-2765