The Effect of an Early Le Fort III Surgery on Permanent Molar Eruption

Abstract

The purpose of this retrospective study was to evaluate the extent to which an early Le Fort III osteotomy affects the position and eruption of the permanent maxillary first and second molars. To test the null hypothesis that there are no changes in eruption patterns, 31 patients diagnosed with craniosynostoses (13 with Crouzon's syndrome, nine with Apert's syndrome, eight with Pfeiffer's syndrome, and one with Carpenter's syndrome) with a mean age at the time of surgery of 5.3 +/- 1.3 years were studied. All patients underwent a Le Fort III osteotomy performed by a single surgeon to correct the anatomical deformity for functional and psychosocial reasons. Eighteen patients with craniosynostoses who had not been operated on (11 with Crouzon's syndrome, four with Apert's syndrome, and three with Pfeiffer's syndrome) served as controls; they had a mean age of 21.2 +/- 9.5 years. First and second molar positions and eruption patterns were assessed separately on panoramic radiographs by three observers. For the patients who underwent surgery, long-term evaluation showed that although 79 percent of all first molars erupted compared with 100 percent for the control group (p < 0.001), only 18 percent of all second permanent molars erupted compared with 89 percent for the control group (p < 0.0001). The authors conclude that in a significant minority of cases, early Le Fort III osteotomy affects first molar eruption, whereas the probability of second molar eruption is significantly decreased in the majority of cases. Therefore, Le Fort III osteotomy sites should be positioned distal to the second molar tooth buds. If this is not possible, patients, parents, and dental professionals should be made aware of these early postosteotomy sequelae so that later treatment planning can be enhanced.

Evaluation of Maxillary Permanent Molars in Patients With Syndromic Craniosynostosis After Monobloc Osteotomy and Midface Advancement With Rigid External Distraction (RED)

“…Surgeons need to carefully complete the pterygomaxillary disjunction and, in certain instances, help themselves with endoscopic techniques. This study is in agreement with that of Santiago et al (2005), in which surgical disruption of the teeth occurred mainly in patients under 5 years old. On the other hand, the observed changes in the position of the second and third molars may not be totally related to surgical trauma but to the rapid creation of space.…”

“…In this study, changes in the maxillary permanent molars after monobloc advancement with RED were analyzed. Our goal was to investigate whether monobloc advance- ment with RED was a safer surgical protocol in regards to preservation and integrity of the maxillary molars than conventional Le Fort III and monobloc advancements (Jensen et al, 2007;Santiago et al, 2005).…”

“…This procedure and the Le Fort III osteotomy have been associated with molar tooth damage in the tuberosity region. Disruption of a normal tooth bud at any stage of development may have a significant effect on its final form and function as a component of the masticatory system (Santiago et al, 2005). Recently, monobloc advancement utilizing rigid external distraction (RED) has been successfully used for the correction of severe midface deficiency in cleft and craniofacial syndromes (Figueroa and Polley, 2007;Figueroa et al, 2001;Jensen et al, 2007;Polley and Figueroa, 1998;Polley et al, 1995;Satoh et al, 2003).…”

A Survey of Orthodontic Treatment in Team Care for Patients With Syndromic Craniosynostosis in Japan

“…Abnormalities of maxillary molars were frequently (58.3%) found in patients who had undergone midface surgery below the age of 6 years ( Figure 6B). This seemed to be caused by injury during midface surgery, and previous reports noted the increased risk of midface advancement in early mixed dentition (Santiago et al, 2005;Sant'Anna et al, 2010). From the point of view of orthodontists, midface advancement should be carried out after age 6 years if other circumstances allow it.…”

“…Early midface advancement sometimes injures tooth buds, and tooth formation is arrested. This finding is usually found in the tooth buds of maxillary molars (Santiago et al, 2005; Sant’Anna et al, 2010).…”