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.
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.
","abstract_html":"<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>","abstract_has_math":false,"creators":["Chamberlain, Craig A."],"institution":null,"degree_name":"Master of Science (MS)","degree_level":"Thesis","degree_discipline":"Dentistry","degree_department":null,"school":null,"contributors":["James Farrage","Joseph M. Caruso","David Rynearson","Craig Andreiko"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1993,"date_issued":"1993-06-01T07:00:00Z","date_published":"1993-06-01T07:00:00Z","updated_at":"2026-07-24T02:54:17Z","subjects":["Orthodontics and Orthodontology","Bicuspid; Orthodontics"],"languages":["English"],"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."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholarsrepository.llu.edu/etd/1228","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["James Farrage","Joseph M. Caruso","David Rynearson","Craig Andreiko"]},{"key":"dc:creator","label":"Author","values":["Chamberlain, Craig A."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"thesis:degree_discipline","label":"Discipline","values":["Dentistry"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (MS)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Orthodontics and Orthodontology","Bicuspid; Orthodontics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["English"]},{"key":"dc:rights","label":"Dc Rights","values":["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."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholarsrepository.llu.edu/etd/1228"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["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.
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.
"]},{"key":"dc:title","label":"Title","values":["A Study of Crown and Root Angulation on Maxillary First and Second Bicuspids"]}]}],"canonical_facts":{"dc:contributor":["James Farrage","Joseph M. Caruso","David Rynearson","Craig Andreiko"],"dc:creator":["Chamberlain, Craig A."],"dc:description.abstract":["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.
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.
"],"dc:identifier":["https://scholarsrepository.llu.edu/etd/1228"],"dc:language":["English"],"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."],"dc:subject":["Orthodontics and Orthodontology","Bicuspid; Orthodontics"],"dc:title":["A Study of Crown and Root Angulation on Maxillary First and Second Bicuspids"],"thesis:degree_discipline":["Dentistry"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Science (MS)"]},"updated_at":"2026-07-24T02:54:17Z"}