Abstract

This study compared the mandibular radius (center of the condyle to gnathion) with the mandibular planes (lower border and GoGn) utilizing serial lateral cephalograms on orthodontically treated and nontreated individuals. Three groups were employed as follows: Group 1 of 38 untreated individuals for serial data on growth alone; Group 2 of 13 patients with Class II, high angle, open bite malocclusions that had been treated with high pull headgear and the edgewise appliance (control representing the least amount of mandibular rotation during orthodontic treatment); and Group 3 of 54 randomly selected orthodontic patients to represent the average mandibular rotation during orthodontic treatment.

The data from the serial cephalograms was statistically tested by computer.

The following conclusions were drawn from this study:

  1. The Y axis appeared better than the mandibular radius for predicting the direction of mandibular growth. They both appeared better than the facial axis. The mandibular planes had the least predictive value.
  2. The mandibular radius was more stable than the mandibular plane during growth.
  3. The mandibular radius was a more sensitive indicator of mandibular rotations than the mandibular planes while the facial axis was the most sensitive measure of mandibular rotations.
  4. The mandibular radius consistently showed smaller standard deviations than the mandibular planes in all measurements used in this study.
  5. The Frankfort horizontal was a more stable reference line than sella-nasion.
  6. During retention the ANB angle continued to decrease an average of .76 degrees.
  7. It is feasible to use the mandibular radius in cephalometric analyses for a more accurate assessment of the mandible and resultant changes during growth and orthodontic treatment.

LLU Discipline

Orthodontics

Department

Dentistry

School

Graduate School

First Advisor

Roland D. Walters

Second Advisor

Judson Klooster

Third Advisor

Alden B. Chase

Fourth Advisor

Lloyd E. Gauntt

Fifth Advisor

Lee E. Olsen

Degree Name

Master of Science (MS)

Degree Level

M.S.

Year Degree Awarded

1971

Date (Title Page)

5-1971

Language

English

Library of Congress/MESH Subject Headings

Mandible; Cephalometry

Type

Thesis

Page Count

vi; 44

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

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