ABSTRACT
Our aim was to evaluate symphyseal distraction in relation to duration of expansion, and to propose an optimised procedure. Eighteen patients (mean (SD) age 19 (7) years) with transverse mandibular deficiency were treated by symphyseal distraction osteogenesis. The mean (SD) anterior dental crowding measured was 6.8 (4.2) mm. We retrospectively compared the width of expansion between the canines (ICE) and expansion between the first molars (IFME) after symphyseal distraction according to the distraction time. The median (range) duration of expansion was 13.6 (7-21) days. The median (range) ICE distraction width was 5.5 (3.4-8) mm and IFME width 3.3 (1-7.9) mm (p<0.001). There was a significant correlation between expansion width and distraction time (p<0.001). The transverse anterior and posterior expansion widths differed significantly until 14 days after expansion. The expansion ratio (ICE:IFME) decreased as expansion time increased. The results suggest that the duration of activated expansion can be predicted from the degree of incisal crowding using the formula: distraction time (days)=0.84+3.4×[IC (mm)]-0.2×[IC (mm)](2).
Subject(s)
Incisor/pathology , Malocclusion/surgery , Mandible/surgery , Osteogenesis, Distraction/methods , Adolescent , Adult , Algorithms , Anatomic Landmarks/pathology , Child , Cuspid/pathology , Dental Arch/pathology , Female , Follow-Up Studies , Humans , Male , Mandible/pathology , Molar/pathology , Orthodontic Appliance Design , Retrospective Studies , Time Factors , Young AdultABSTRACT
Because dental dysmorphias make up a large part of the problems we deal with in our daily practices, it is important that we classify them according to their severity. Accordingly, we should define the relevant concepts of norm, anomaly, dysmorphia, and malformation. Over the years these notions have been viewed in a great variety of ways depending on the epoch and the particular society. It seems that nowadays our concepts, enflamed by a relentless media, are orienting themselves toward a more and more narrow concept of what constitutes normality. Our professional attitude is not immune to this societal problem, and many practitioners are tempted to propose treatment when the need for it is uncertain.