Thesis (M.Sc.D.)--Boston University School of Graduate Dentistry, 1973. Orthodontics. / Bibliography included. / In a departure from the notion that the Begg appliance does not disturb the patterns of typical growth changes, 21 untreated and 20 "Begg-treated” Class II, division 1 individuals were analyzed and compared through the use of serial, longitudinal cephalometric measurements. The age range of 10 to 14 years presumably includes a parapubertal growth rate acceleration for each sample. Various angular and linear measurements were determined. In addition, intragroup treatment behavior was observed in the Begg sample.
Among the untreated controls, the chin point grew forward with age and thereby reduced the facial convexity. The maxilla (SA) was found to be relatively stable. ANB closure approached 1.0 degree both for this group as well as in the treated sample. However, the closure in the Begg patients appeared to result solely from point A retraction or SNA reduction since the chin points and SNB showed no forward migration in the presence of therapy. The speculation occurs, then, that had not the chin been so restrained, there would have been more profile fattening and apical base alignment.
Regarding the spatial position of the chin, another observation was that "counter clockwise" rotation of the mandibular plane presented in the control group. At best, the mandibular plane showed no change for overall treatment, which by comparison to the controls effectively designated disturbance of the growth pattern. Correlations between pogonion, mandibular plane and SNB were quite significant in both groups.
Finally, it was determined that intra-group Begg treatment changes expressed tendencies generally found in the literature. These changes, too, were discussed and evaluated against the control sample. Interestingly enough, for example, the upper first molar protracted no further mesially in Begg treatment than it would have migrated if left undisturbed.
| Identifer | oai:union.ndltd.org:bu.edu/oai:open.bu.edu:2144/29787 |
| Date | January 1973 |
| Creators | Eddy, S Grayson |
| Publisher | Boston University |
| Source Sets | Boston University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
| Rights | This work is being made available in OpenBU by permission of its author, and is available for research purposes only. All rights are reserved to the author. |
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