Abstract

The purpose of this research was to determine if the advancements of cephalometrics and the capacity of the computer to quantify skeletal relationships could help the orthodontist recognize those cases where arch length could be gained through buccal expansion with little risk of relapse. To determine the stability of orthodontic treatment changes, the mandibular arches of 72 patients were studied. The cases were treated by Drs. Bench and Ricketts and were selected on the basis that each case must include three complete sets of frontal and lateral headplates, before and after treatment, and a minimum of two years out of retention.

Measurements were made of the intercanine width from cusp tip to cusp tip. Intermolar width was measured from the widest point on the buccal surface of the molar. The molar to jaw dimension, right and left sides, was measured from the buccal surface of the first molar to a line connecting the jugal process of the maxilla to the trihedral emminence on the body of the mandible. The four measurements were recorded before treatment started, at the end of treatment and a minimum of two years out of retention.

The following conclusions were drawn from this investigation:

  1. The frontal x-ray can be an accurate means of evaluating the dentition and its relation to the jaws.
  2. Serious consideration for intercanine expansion should be given to those cases with an intercanine width of less than 26 mm.
  3. A highly significant relationship was found between two measurements: molar to jaw distance and lower face height, and those cases that relapse in intermolar dimension and those that did not relapse.
  4. In non-extraction cases the intermolar width was expanded an average of .75 mm with very stable post-retention results. Average intercanine width expansion was 2.4 mm which would have a significant effect on arch length gain.

In the past a number of thesis have evolved which completely ruled out the possibility of buccal expansion. In this study a means of classifying individuals into subgroups was proposed to determine the probability of relapse if arch length was gained through buccal expansion.

LLU Discipline

Orthodontics

Department

Dentistry

School

Graduate School

First Advisor

Robert J. Schulhof

Second Advisor

Roland D. Walters

Third Advisor

Steve N. Asahino

Fourth Advisor

Logan W. Barnard

Fifth Advisor

Arthur J. Morgan

Sixth Advisor

Gary G. Morikone

Degree Name

Master of Science (MS)

Degree Level

M.S.

Year Degree Awarded

1975

Date (Title Page)

5-1975

Language

English

Library of Congress/MESH Subject Headings

Orthodontics; Cephalometry

Type

Thesis

Page Count

viii; 66

Digital Format

PDF

Digital Publisher

Loma Linda University Libraries

Usage 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.

Collection

Loma Linda University Electronic Theses and Dissertations

Collection Website

http://scholarsrepository.llu.edu/etd/

Repository

Loma Linda University. Del E. Webb Memorial Library. University Archives

Download

Share

COinS