Paramedian unilateral Le Fort I osteotomy.

A novel maxillary osteotomy is designed which is a technical modification of the standard Le Fort I osteotomy, termed the paramedian unilateral Le Fort I osteotomy. This technique has been used to correct an anterior open bite in a given patient based on the current clinical scenario as described, secondary to post ankylosis surgery. Its use may be extrapolated to various clinical situations to correct occlusal discrepancies including distraction osteogenesis.

INTRODUCTION

Orthognathic surgery of the maxilla was first described by Von Langenbeck (1859) for the removal of nasopharyngeal polyps.[1] Wassmund (1927) first described the Le Fort I osteotomy for the correction of mid-face deformities.[2] Obwegeser (1965) précised the operative technique and suggested complete mobilization of the maxilla.[3] Several surgeons followed the suit and further developed and refined the technique of Le Fort I osteotomy. Ever since its inception, the Le Fort I osteotomy has evolved through various modifications such as the high Le Fort I, pyramidal, middle, intermediary, quadrangular, horseshoe, and maxillo-malar-infraorbital osteotomies.[4] Even today, the technique of Le Fort I osteotomy is under constant modification and revision and is tailored to different clinical situations, treatment objectives, and surgeon's experience. This paramedian unilateral Le Fort I osteotomy is a modification that has been carried out to address a given clinical scenario and may be extrapolated to various other clinical situations as well.

A 21-year-old male patient presented with a complaint of difficulty in chewing and inability to close the mouth. History revealed a gap arthroplasty for a right temporomandibular joint ankylosis at 17 years, a failed and eventful tissue expansion procedure for the right cheek defect at age 18 and a consequent cervicofacial flap and skin graft for oral lining followed by a mandibular osteotomy (right sagittal split and left intraoral vertical ramus osteotomy) for correction of the facial deformity at age 19. Currently presented with the following clinical scenario [Figure 1].

Figure 1

Preoperative view of the patient – (a) Right lateral oblique view; (b and c) Intraoral view

An anterior open bite (AOB) of 18 mm and a mouth opening of 34 mm

A severe posterior gag in the left 2nd and 3rd molar region

Severe supra eruption of the lower anterior teeth producing a gross distortion in the mandibular occlusal plane

Loss of all posterior teeth in the right mandibular quadrant

Loss of all the teeth in the maxillary right quadrant except 11 and 16

Severe fibrosis of the right cheek with loss of upper and lower vestibules

Paresis of the lower division of the right facial nerve.

TECHNIQUE

In view of the current clinical scenario and the past surgical history, the case was taken up for correction of the AOB by addressing the maxilla. In view of the absence of teeth in the right maxillary quadrant (except first molar) and the severity of fibrosis in the right bucco-vestibular region, a paramedian unilateral Le Fort I osteotomy was contemplated.

Under standard general anesthetic operative conditions via a maxillary translabial vestibular approach the maxilla was exposed keeping the incision restricted up to the canine region on the right side just adequate to expose the pyriform aperture. On the right, a 1 cm crestal incision was made distal to the existing right central incisor to facilitate elevation of the mucoperiosteum of the hard palate all the way down to the soft palate junction about 10–12 mm away from the midline. In situations where a full complement of teeth is present the labial, and the palatal mucoperiosteum may be elevated using a gingival crevicular incision both in the labial and palatal aspects. Standard osteotomy cuts were employed to disarticulate the maxilla on the left side and from the nasal septal articulations. On the right a vertical osteotomy cut was made from the lateral limit of the pyriform aperture down to the residual alveolus and was carried out posteriorly to the posterior edge of the hard palate along the floor of the nasal cavity using a guarded osteotome [Figure 2a]. Due caution was exercised to protect the tissues of the nasal floor and the palatal mucoperiosteum using malleable retractors. The maxilla was now completely disarticulated and mobilized using a spreader and a hook [Figure 2b]. The osteotomized unilateral maxilla was now differentially repositioned to occlude with the mandible in the best intercuspation possible by eliminating the bony interferences along the septum and the posterior maxilla. This reasonably favorable occlusal intercuspation was facilitated by an antero-inferior tip of the maxilla by 4–5 mm and a posterior intrusion by 7–8 mm. Fixation was carried out using 1.5 mm stainless steel plates and screws (6 mm) [Figure 2c]. Wound closure was accomplished with 3–0 vicryl sutures after thorough wound debridement and hemostasis [Figure 2d]. A standard extubation protocol and routine postoperative care were followed until discharge. The preoperative and postoperative radiographs of the patient have been illustrated in Figure 3, and the postoperative view of the patient has been illustrated in Figure 4. The Paramedian unilateral Le Fort I osteotomy has been depicted with the help of line diagrams from the nasal and palatal views for easy understanding in Figures 5 and 6.

Figure 2

Intraoperative view – (a) Design of the paramedian unilateral Le Fort I osteotomy; (b) Unilateral disarticulation of the maxilla; (c) Fixation of the osteotomized unilateral maxilla; (d) Postoperative intraoral view of the patient showing anterior open bite correction

Figure 3

Preoperative and postoperative radiographs of the patient – (a) Preoperative cephalogram of the patient; (b) Postoperative cephalogram of the patient; (c) Preoperative OPG of the patient; (d) Postoperative OPG of the patient

Figure 4

Postoperative view of the patient – (a) Frontal view; (b and c) Intraoral view

Figure 5

Paramedian unilateral osteotomy cut shown from the nasal view

Figure 6

Paramedian unilateral osteotomy cut shown from the palatal view

CLINICAL APPLICATIONS

This technique may be employed and extrapolated to various clinical situations where occlusal discrepancies occur secondary to trauma and in other various syndromic and nonsyndromic facial deformity corrections. Furthermore, the use of paramedian unilateral Le Fort I osteotomy may be extended to maxillary distraction osteogenesis.