Original scientific paper

Cephalometric Point “A” Position Following Palatal Expansion

Allan G. Farman ; The University of Louisville Scholl of Dentistry, Louisville, Kentucky 40292, USA
Paul M. Cottone ; The University of Louisville Scholl of Dentistry, Louisville, Kentucky 40292, USA

Abstract

Objectives: Palatal expansion is used to treat severely constricted maxillary arches associated with a posterior unilateral o f bilateral crossbite. The purpose of this study was to evaluate the affects of such treatment on the position of the “A ” point. Material and Methods: Ninety six cases where palatal expansion was the first orthodontic treatment were retrospectively analyzed using lateral cephalographs taken before and after the expansion phase. Vertical movement of “A ” point was assessed relative to the perpendicular distance from the Frankfort Horizontal Plane and from the anterior cranial base (Sella-Nasion). Horizontal movement o f “A ” point was measured parallel to the Frankfort Plane using a line tangenital to the posterior limit of the pterygomandibular fissure and also parallel to the anterior cranial base from point Sella. Subgroups o f “rapid” and “slow” palatal expansion were compared. Results: Here was a mean downward and forward movement o f point “A ” during palatal expansion, with displacement being greater on average with rapid than with slow palatal expansion therapy. The mean vertical component changes relative to speed of palatal expansion was statistically significant (p<0.1). The horizontal component averaged > 1 mm more with rapid palatal expansion compared to slow expansion; however, no statistical significance was proven. Mean increase in the mandibular plane angel was 1.4° to 2.0°. Conclusions: Palatal expansion is generally associated with a downward and forward movement o f point “A ” which is greater on average with rapid than with slow activation therapy.

Keywords

cephalometrics; orthodontic therapy; palatal expansion therapy

Hrčak ID:

99386

URI

https://hrcak.srce.hr/99386

Publication date:

15.6.1997.

Article data in other languages: croatian

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