The effect of first premolars extractions on the lower anterior facial height.

Flávio Marcos de ALMEIDA, Vania Célia Vieira de SIQUEIRA

Premolar extractions are often utilized as part of orthodontic treatment to solve a wide range of problems. However, its use to control vertical dimension is still controversial. This retrospective study investigated the lateral cephalometric measurements of 30 dolichocephalic girls, with Class II division 1 malocclusion. These patients were treated with edgewise appliances and high traction headgear. From the whole group 15 had four first bicuspids extractions and 15 had no extractions. The mean age was 12.3 years, ranging from 9 to 17 years. The cephalometric measurements N-Me, N-ANS, ANS-Me, S-Go, Ar-Go, 6-PP, 6-ANSperp, 6-GoGn, 6-Pogperp, SN.GoGn, SN.PP, PP.GoGn, ANS-Me/N-Me, S-Go/N-Me, and Go-Ar/S-Go were used in the study. The study revealed that: 1) the extraction of the first premolar associated with extrusion of the first molars and growth did not cause any difference in the lower anterior facial height between the two groups; 2) both upper and lower first molars moved mesially in the extraction group; 3) the increase in the lower anterior facial height was similar for both groups; 4) the total anterior facial height was larger in the non extraction group due to a higher increase in the upper anterior facial height; and 5)- the angular measurements did not change significantly in both groups during treatment, most likely because growth between the posterior and the anterior vertical dimension were balanced.

Keywords: Anterior facial height. Extractions. Premolars.

Saturday, November 23, 2024 09:47