Segmental Maxillary Osteotomies in Conjunction With Bimaxillary Orthognathic and Intranasal Surgery: Indications - Safety - Outcome

 

            The purpose of this study was to assess the: indications; safety; and results of maxillary segmental osteotomies used to manage arch form anomalies as part of the patient’s orthognathic correction. 

            The authors executed a retrospective case series derived from patients treated by a single surgeon between 2004 and 2013.  A consecutive series of subjects with both chronic obstructed nasal breathing and a dentofacial deformity (DFD) scheduled for simultaneous Le Fort I; sagittal ramus osteotomies; septoplasty; inferior turbinate reduction; and osseous genioplasty procedures were identified.  Demographic variables included age and gender.  Other variables included the pattern of presenting DFD and the orthodontist providing care.  The outcome variables studied were:  presence of arch form anomalies; occurrence of maxillary complications; and need for re-operation.  Assessment of treatment outcome as judged by each subjects treating orthodontist was documented through a questionnaire completed at > one year after surgery.  The data was entered in a database using Microsoft Access.  This included information from standardized pre and post-operative photographs and radiographs.  Descriptive statistics were computed for all variables.

            During the study period, 262 subjects met the inclusion criteria.  Their age at operation averaged 25 years  and included 134 females (51%).  The pattern of presenting DFD includes:  long face (27.8%); maxillary deficiency (27.9%); asymmetric mandibular excess (18.7%); mandibular deficiency (12.6%); short face (11.5%); and bimaxillary dental protrusion (1.5%). 

Thirty percent of subjects presented with an arch width skeletal anomaly benefiting from a 2-segment Le Fort I.  Thirty-four percent presented with both arch width and curve of Spee skeletal anomalies requiring a 3-segment LeFort I.

            In no case (segmental or non-segmental) was there direct surgical injury to a dental root or perforation through the lamina dura.  Analysis of periodontal status after maxillary segmental osteotomies included 1,002 sites.  The findings include 14/1,002 sites with reduced gingival levels (1.4%); We also analyzed the periodontal status after non-segmental LeFort I as a comparison group.  The findings include 10/564 (2%) sites with reduced gingival levels.  In 1,572 teeth at risk, 3 sustained a pulpal injury (segmental- nonsegmental).  In each case, root canal therapy was successfully accomplished.  There were no cases of wound infection, fibrous union or aseptic necrosis in the maxillary region.  Two of the segmental osteotomy subjects sustained a persistent oronasal fistula. Each were successfully closed with palatal flaps.  Only 2 of the 262 subjects required hardware removal.

            The treating orthodontist’s assessment of occlusal outcome after segmental LeFort I rated: 92% of subjects as favorable; 5.6% as having a less than ideal occlusion; and 2.4% with an unfavorable occlusion.  Assessment of facial aesthetics confirmed a favorable result in 98% of study subjects.  The orthodontist’s found improved efficiency of care provided segmental LeFort I in 98% of subjects.  Only one of the subjects were considered by their orthodontist to have sustained a dental injury and only 3 were believed to have a degree of periodontal deterioration as a result of the maxillary surgery.

            A majority of DFD patients presenting for bimaxillary orthognathic correction will have skeletal arch form anomalies. Segmentation of the LeFort I is a safe method of addressing skeletal arch form anomalies.  Orthodontists report a high level of satisfaction with the occlusion and facial aesthetic results after orthognathic surgery that includes maxillary segmental osteotomies.  Orthodontists also report improved efficiency of care delivered with few dental injuries or periodontal sequela. 

1.  Ho MW, Boyle MA, Cooper JC, Dodd MD, Richardson D: Surgical complications of segmental Le Fort I osteotomy.  British J. Oral Maxillofac Surg. 49:562, 2011

2.  Mordenfeld A, Andersson L: Periodontal and pulpal condition of the central incisors after midline osteotomy of the maxilla.  J. Oral Maxillofac. Surg: 57:523, 1999