The canine jugum is a bony eminence over the maxillary canine root on the facial surface of the maxilla. With the splint wired to the maxillary dentition, place the patient in intermaxillary fixation with a heavy stainless steel wire placed bilaterally. This can lead to a postoperative anterior open bite discrepancy. Although the saws are somewhat quicker, the loss of fine touch in using the saws can be detrimental. 11.1 ). Most of the maxillary bone is light and fragile, the exception being the portion that holds the teeth. David E. Frost, Michael P. Powers, in Maxillofacial Surgery (Third Edition), 2017, The most popular and useful approach to skeletal correction of maxillary deformities is via the total maxillary osteotomy or Le Fort I osteotomy.7-9 The surgical procedure has been developed to allow for multiple modifications to correct three-dimensional deformities of the maxillary complex. Application of the same surgical principles and procedures in patients with anatomic abnormalities that contribute to narrowing or obstruction of the pharyngeal airway during sleep will produce predictable and successful outcomes. This thickened area of bone can be cut with the reciprocating saw or the rotary instrument. This option follows a principle based on scientific rationale rather than trial and error, and, in most cases, will negate the need for multiple surgeries. Anesthetic management of these patients is beyond the scope of this chapter and is not dealt with further. pregnancy. mandible including (fetal hypopharynx is visible). This area is characterized by type D1 bone. Place retraction (toe-in retractors placed on bone) under the flaps to allow for adequate visualization and then apply digital downward pressure to the anterior maxilla. IFA was defined on a sagittal view by the crossing of two lines: The MD and MX were measured Use a small fissure bur, an oscillating saw, or a sagittal saw to complete these interdental cuts. Measure the amount of predicted superior repositioning or inferior repositioning and hold the maxilla in place at this position. If the maxilla is to be repositioned inferiorly to any significant degree, this vessel must be clipped to avoid a possible laceration in the stretching process of inferior repositioning. A CT of the mandible/maxilla can help your physician to assess any injury, infection, or other abnormalities. The maxilla tends to have a high arched palate or cleft (30%). CT scans use X-ray technology and advanced computer analysis to create detailed pictures of the body. Maxillary fractures often present with a history of trauma and clinical signs of epistaxis, facial deformity, malocclusion, and patient discomfort. There does exist more advanced surgical techniques where the implants may extend into the nasal cavity 2 to 4 mm via a subnasal graft; however, these procedures should only be completed in ideal circumstances (Fig. objective determination of fetal jaw size. Traditionally, researchers believed that mesenchymal cells receive signals from the HERS for tooth root elongation (Cate, 1996). To avoid the necessity of a four-piece maxillary osteotomy and to allow for proper posterior and canine expansion, use the osteotomy between the lateral incisor and the canine. The incisive canal is bilobate, opening via the incisive foramen, with each lobe enclosed by one of the maxillae. The osteotome is not intended to cleave off the pterygoid plates at this time, nor is it desirable to traverse through the descending palatine vasculature. Remove the splint and verify the bite with the dentition as well. Identify and relieve any impingements until the vertical position of the maxilla is achieved as dictated by the preoperative planning. Once the reference measurements have been taken and recorded, complete the lateral osteotomy using a reciprocating saw or a rotary instrument (Figure 76-11). Otto C, Platt LD. For this reason, use of a small fissure bur to make the lateral cortical scoring cuts and then use of a small thin spatula osteotome to complete the cuts through to the palate is preferable. Down-fracturing of the, Selecting a suitable site for miniscrew implant insertion, Skeletal Anchorage in Orthodontic Treatment of Class II Malocclusion, Based on these considerations, possible insertion sites in the, The bone of the mandible is more compact than that of the, Misch's Avoiding Complications in Oral Implantology, Cranial bone grafting in maxillary preprosthetic surgery, Le Douarin, Creuzet, Couly, & Dupin, 2004. Fetal mandible length (FML) Anatomy of maxilla and mandible 1. In general, segmentalization is done (1) between the central incisors for a two-piece maxillary osteotomy for expansion, (2) between the canine and the premolar for a three-piece maxillary osteotomy for posterior expansion and differential superior repositioning, or (3) between the canine and the lateral incisor for differential superior repositioning and for expansion including the canines. Bone grafting is appropriate for inferior repositioning and for any substantial gaps between the mobilized inferiorly repositioned maxilla and the stable superior bony base. Small impingements in this area can cause distraction of the condyles when one is rotating the maxillomandibular complex superiorly. Personally, we have not had this problem and think that the attention to prevention of anterior open bite is achieved best when the maxillomandibular complex is passively positioned superiorly. A modified version of this classification, based not only on the ratio of cortical to medullary bone but also on the macroscopic characteristics of the bony tissue, was proposed in 1987 by Misch, who identified five different bone densities (D1–D5) (Fig.