Forced-eruption time for palatally impacted canines treated with and without ostectomy-decortication technique

Abstract

Objectives: To compare forced-eruption times for palatally impacted canines treated with and without the ostectomy-decortication technique and to assess the influence of palatally impacted canine pretreatment position and angle on forced-eruption time.

Materials and methods: The sample was composed of 118 patient-subjects with 151 palatally impacted canines treated with the ostectomy-decortication technique (n = 72) and without (n = 79). The orthopantomogram radiographs (OPGs) were analyzed for palatally impacted canine angle and horizontal and vertical position. Recovery time was measured from the start of forced eruption until the canine was within ±1 mm of final dental arch position.

Results: The time of forced canine eruption with ostectomy-decortication technique was significantly shorter than without (6.6 vs 21.0 months). Pretreatment canine position significantly increased forced-eruption time in the ostectomy-decortication group but not in the control sample.

Conclusions: Forced-eruption time of palatally impacted canines using the ostectomy-decortication technique was 3.2 times more rapid than without. Forced-eruption time increased significantly as a function of pretreatment palatally impacted canine position severity in the ostectomy-decortication group but not in the control.

Keywords: Forced eruption; Orthodontics; Palatally impacted canine.

Figures

Figure 1.

Ostectomy-decortication technique: (A) presurgery, (B) full-thickness flap, (C) extracted primary canine, (D) ostectomy-decortication, (E) bracket placement and traction forces, (F) flap closure over surgical exposure, (G) cortical bone penetrations (decortication) surrounding palatally impacted canine (circles in G), and (H) removal of bone (ostectomy) between palatally impacted canine crown and future occlusal position (curved lines in G and H).

Figure 2.

Position of palatally impacted canine was measured by angle of the canine long axis to OPG midline (angle), vertical distance from canine cusp tip to OPG occlusal plane (d1), and horizontal distance from canine cusp tip to OPG midline (d2).

Figure 3.

Forced-eruption times in the experimental group compared by palatally impacted canine position (angle, horizontal, and vertical) as a function of severity (subgrp) demonstrated significantly greater forced-eruption times for the most severe position (subgrp 3).

Figure 4.

Representation of severe palatally impacted canine positions with 63° angle, 3 mm horizontal to midline, and 13.5 mm vertical to occlusal plane illustrated with portion of OPG and diagrammatic overlays. Forced-eruption times for two patients with these nearly identical severe palatally impacted canine conditions were 407 days (13.6 months) for experimental and 956 days (31.9 months) for control—a difference of 2.4 times.