The Oral and Maxillofacial Surgery Anesthesia Team Model.

Oral and maxillofacial surgeons have been providing safe anesthesia to their patients using the anesthesia team model; this has allowed access to care for patients that have significant anxiety. The AAOMS strives to maintain the excellent safety record of the anesthesia team model by creating simulation programs in anesthesia, regularly updating the office anesthesia evaluation program, convening anesthesia safety conferences and strengthening the standards in our training programs. Through these efforts, our delivery of anesthesia to our patients will remain safe and effective.

Technical factors accounting for stability of a bilateral sagittal split osteotomy advancement: wire osteosynthesis versus rigid fixation.

OBJECTIVE: Relapse after bilateral sagittal split osteotomy has been attributed to various technical factors that are inherent in the surgical procedure. The purpose of this article was to analyze technical factors that predispose to relapse when wire or rigid fixation is used. STUDY DESIGN: Patients were randomized to either rigid or wire osteosynthesis. Cephalometric radiographs were obtained and digitized at multiple time periods before and after surgery. Data were analyzed through use of 2-sample t tests and stepwise regression analyses. RESULTS: Multivariate analysis indicated that the following factors correlated with relapse: initial advancement, change in ramus in inclination, change in the mandibular plane, and fixation type. CONCLUSIONS: Relapse increased with the amount of initial advancement and, to a lesser extent, with control of the proximal segment and change in the mandibular plane. These factors are similar for wire osteosynthesis and rigid fixation.

Short-term changes of condylar position after sagittal split osteotomy for mandibular advancement.

OBJECTIVE: The goal of this study was to quantify condylar position changes after mandibular advancement surgery with rigid fixation (screws). Radiographic changes in condylar position were determined in all planes (X, Y, and Z). Computed tomography with image reconstruction was used. STUDY DESIGN: A consecutive population of patients who elected to have rigid fixation for surgical stabilization method were studied (n = 21). Computed tomography data were acquired in the axial plane through use of abutting 1.5-mm-thick slices. Data acquisition occurred 1 week preoperatively and 8 weeks postoperatively. Measurements were made from 2-dimensional reconstructions. RESULTS: The averages were as follows: lateral displacement from midline, 1.2 mm (55% of patients); medial displacement from midline, 1.5 mm (45% of patients; range, 3.2 mm); condyle angle increase from coronal plane, 3.5 degrees (60% of patients); condyle angle decrease from coronal, 4.3 degrees (40% of patients; range, 8.5 degrees); superior rotation of proximal segment, 3.2 degrees (39% of patients); inferior rotation of proximal segment, 8.6 degrees (61% of patients; range, 15.6 degrees); superior displacement, 1.2 mm (60% of patients); inferior displacement, 1.0 mm (40% of patients; range, 2.5 mm); anterior displacement, 1.6 mm (33% of patients); posterior displacement, 1.6 mm (67% of patients; range, 2.8 mm). CONCLUSIONS: Changes occurred in all planes, but the most common postoperative condyle position was more lateral; with increased angle, the coronoid process was higher and the condyle was more superior and posterior in the fossa.

Condylar position with rigid fixation versus wire osteosynthesis of a sagittal split advancement.

PURPOSE: In this randomized clinical study, two groups of patients who underwent a bilateral sagittal split osteotomy and either wire osteosynthesis or rigid fixation were compared. PATIENTS AND METHODS: Cephalometric radiographs obtained before surgery, immediately after surgery, and at 8 weeks, 6 months, and 1 and 2 years after surgery were available for 125 of these patients, 63 with wire fixation and 62 with rigid fixation. All were traced by an independent examiner, and vertical and horizontal changes in condylar position were recorded for each period. RESULTS: Condylar movement was slightly different with the two fixation techniques beyond 8 weeks postsurgery, but the ultimate position of the condyle was not different. The condyles in both groups moved posterior and superior. There initially was a correlation between the amount of advancement and the amount the condyle moved inferior in both groups, but this diminished with time. In addition, there was a weak but significant positive relationship between forward rotation of the proximal segment and superior condylar position immediately after surgery, which did not exist at later periods. CONCLUSIONS: Whether wire osteosynthesis or rigid fixation was used, the ultimate condylar position was posterior and superior after a bilateral sagittal split osteotomy to advance the mandible. No single factor could be identified to account for this change. It is suggested that change in mechanical load may have resulted in remodeling and adaptation of the condyles.

Effects of major Class II occlusal corrections on temporomandibular signs and symptoms.

This study explored the relationship between malocclusion and signs and symptoms of temporomandibular disorders (TMD) in 124 patients with severe Class II malocclusion, before and 2 years after bilateral sagittal split osteotomy (BSSO). Patients were evaluated with the Craniomandibular Index (CMI), the Peer Assessment Rating Index (PAR Index, to assess gross changes in the occlusion), and symptom questionnaires. The results showed a significant improvement in occlusion; PAR Index scores dropped from a mean of 18.1 before surgery to a mean of 6.1 at 2 years postsurgery (P < 0.001). The CMI and masticatory index (MI) for muscle pain indicated clinically small but statistically significant improvement (P = 0.0001) from before surgery (mean CMI = 0.14, mean MI = 0.15) to after surgery (mean CMI = 0.10, mean MI = 0.08). The number of patients with clicking upon opening decreased significantly from 33 (26.6%) to 13 (10.5%) (P = 0.001). However, the number of patients with fine crepitus increased from 5 (4.0%) before surgery to 16 (12.9%) at 2 years postsurgery (P = 0.005). Significant reductions in subjective pain and discomfort were also found 2 years after surgery. The magnitude of change in muscular pain was not related to the severity of the pretreatment malocclusion, a finding that suggests that factors other than malocclusion may be responsible for the change in TMD.

Health-related quality of life following orthognathic surgery.

A randomized controlled trial was conducted to compare the effects of rigid and wire fixation on health-related quality of life following surgical mandibular advancement in patients with Class II malocclusions. Sixty-four patients randomly selected to receive rigid fixation with bicortical position screws were compared with 63 patients randomly selected to receive nonrigid fixation with inferior border wires. Quality of life was measured using the Sickness Impact Profile, a generic measure of health-related quality of life, and the Oral Health Status Questionnaire, a specific measure of oral health and function designed for use with orthognathic surgery patients. Patients were evaluated prior to application of orthodontic appliances, approximately 2 weeks before surgery, and 1 week, 8 weeks, 6 months, 1 year, and 2 years following surgery. Neither instrument revealed a statistically significant difference in quality of life between wire and rigid fixation at any time period. The health-related disability associated with Class II malocclusion is modest compared to many other medical conditions. Nonetheless, orthognathic surgery patients exhibit progressive and statistically significant improvement in health-related quality of life across a wide variety of functional domains, regardless of the fixation method used.

Effects of hypesthesia on oral behaviors of the orthognathic surgery patient.

PURPOSE: The purpose of this study was to compare orthognathic surgery patients with and without significant hypesthesia with respect to perceived problems with specific oral behaviors. PATIENTS AND METHODS: Data from 116 patients 6 months after bilateral sagittal split osteotomy (BSSO) and mandibular advancement were analyzed. Tactile sensation in the right and left mental nerve areas was determined using monofilaments and brush strokes (von Frey hairs). The right infraorbital region was used as a control. A difference of 450 mg of force between the control and test sites was considered significant hypesthesia. Patients rated their level of subjective problems with swallowing liquids or solids, smiling, spitting, kissing, speaking, eating, and drooling on a scale from 1 (none to mild) to 7 (extreme). A value of 5 or greater was considered significant impairment. RESULTS: Hypesthesia was shown in 23 patients (19.8%) with the monofilaments and in 29 patients (25.0%) using brush stroke direction. In each of these two groups, a significant correlation was observed between hypesthesia and difficulty in chewing and kissing. No correlation was observed between any of the remaining seven oral behaviors and hypesthesia. CONCLUSION: These findings suggest that only certain oral behaviors are affected by hypesthesia of the mental nerve.

Clinical evaluation of hydroxyapatite-coated titanium plasma-sprayed and titanium plasma-sprayed cylinder dental implants: a preliminary report.

OBJECTIVE: The purpose of this article was to present the preliminary results of a prospective clinical trial comparing titanium plasma-sprayed versus hydroxyapatite-coated titanium plasma-sprayed cylinder (press fit) implants in different regions of the mouth. STUDY DESIGN: Sixty-five subjects met the inclusion requirements. Surgery was done in two phases by four experienced surgeons. Implant placement and abutment connection were separated by 3 to 4 months in the mandible, 6 to 7 months in the maxilla. Patients were assigned to either titanium plasma-sprayed or hydroxyapatite-coated implants on the day of surgery. Implant placement was not stratified for the region of the jaws. Outcome assessment was failure (loss) of an implant before or within 3 months of second phase surgery. RESULTS: Three hundred fifty-two implants equally distributed between titanium plasma-sprayed and hydroxyapatite-coated titanium plasma-sprayed implants were placed in four different sites; anterior maxilla, posterior maxilla, anterior mandible, and posterior mandible. There were a total of 15 failures (4.26%). Overall, titanium plasma-sprayed implants showed a higher but not significant failure rate compared with hydroxyapatite-coated implants (p = 0.06). Although not statistically significant, we believe that a smoking history played an important role in the failure of implants. CONCLUSION: This study suggests that an hydroxyapatite-coating of an implant allows superior initial integration when compared with a titanium plasma-sprayed surface.

A comparison of questionnaire versus monofilament assessment of neurosensory deficit.

PURPOSE: Because neurosensory deficit is commonly reported by patients after orthognathic surgery, it is important to know how accurately patients can report their own sensory deficit. This analysis compares the results of objective neurosensory tests with the results of a subjective patient questionnaire. MATERIALS AND METHODS: Before and 6 months after bilateral mandibular sagittal ramus split osteotomy, 101 patients with class II facial deformities were asked to rate sensations of numbness or tingling in the area of the mental nerve. Simultaneously, they were objectively tested using monofilament neurosensory tests (light touch and brush stroke direction). RESULTS: More than 70% of patients subjectively reported neurosensory problems, but objective assessment identified neurosensory deficits in less than 60% of the patients. The sensitivity and specificity of the patients' subjective assessments were 75.3% and 52.8%, respectively, for the light touch test, and 77.9% and 59.8%, respectively, for the brush stroke test. CONCLUSIONS: It was concluded that when monofilament neurosensory testing is used as the gold standard, patients appear to overreport neurosensory problems; ie, the positive predictive value of patient reports is only 63.2%, resulting in frequent false positives.

Comparison of cephalometric analysis with ethnicity in obstructive sleep apnea syndrome.

Many studies have documented significant craniomandibular abnormalities in obstructive sleep apnea syndrome (OSAS) patients. Recent literature clearly describes the cephalometric abnormalities commonly associated with OSAS. Studies have not evaluated specific cephalometric abnormalities that may contribute to OSAS by various ethnic groups. Data were collected on 48 patients (20 Caucasian, 15 Black and 13 Hispanic) with completed cephalometric analysis and polysomnography. Cephalometric landmarks, angles and measurements [angle measured from sella to nasion to subspinale point (SNA), angle measured from sella to nasion to supramentale point (SNB), difference between SNA and SNB (ANB), perpendicular distance from gonion to gnathion to hyoid (MP-H), distance from posterior nasal spine to tip of soft palate (PNS-P) and posterior airway space (PAS)] commonly used in the evaluation of OSAS patients were recorded. Measurements were normalized by dividing the observed value by the mean value for the ethnic group. Statistically significant differences in normalized SNA and SNB appeared in the Black and Hispanic groups when compared to the Caucasian group. For both SNA and SNB, Blacks averaged approximately 3.5% above their ethnic mean, whereas Hispanics averaged 1.8-2.8% below their ethnic mean. There was a statistically significant correlation between respiratory distress index (RDI) and MP-H. These baseline cephalometric differences in the ethnic groups studied suggest that surgical intervention might be approached differently in various ethnic groups. Further studies that evaluate the surgical success achieved by various procedures among different ethnic groups may help define surgical protocol in various ethnic groups for OSAS.

Stability of simultaneous modified LeFort III/LeFort I osteotomies.

The objective of this study was to examine maxillary skeletal stability after simultaneous modified LeFort III/LeFort I osteotomy in patients who presented for the simultaneous correction of midface and maxillary hypoplasia. Eleven patients underwent simultaneous modified LeFort III/LeFort I osteotomies using transoral and transconjunctival surgical approaches. The mean net surgical movement at A point (A pt) was 5.2 mm anteriorly and 2 mm inferiorly. Titanium mini-plates were used to stabilize both the midface component and the LeFort I segment; iliac crest or calvarial bone grafts as well as freeze-dried cancellous blocks were used at the zygoma and lateral orbital rim regions. All patients had lateral cephalometric radiographs taken immediately postoperatively, and at their sixth week, sixth month, and one year follow-up visits. Five maxillary landmarks (CI, A pt, ANS, PNS, and 2M) were used to examine the horizontal and vertical changes occurring at each time period. The central incisor relapsed vertically 2.8 mm at six months, A pt relapsed vertically 2.3 mm at six months, ANS relapsed posteriorly 1.6 mm at 6 weeks, PNS relapsed 1.5 mm anteriorly at one year. This study demonstrated that the maxilla moved anteriorly 1.5 mm and superiorly 2.8 mm in simultaneous modified LeFort III/LeFort I osteotomies performed with mini-plate fixation and bone grafts. This movement should be considered when planning and performing simultaneous surgical movement of the maxilla and midface using modified LeFort II/LeFort I osteotomies. Appropriate occlusal overcorrection at the time of surgery is necessary.

Surgical correction of facial deformities in a patient with cleidocranial dysplasia.

A one-stage procedure for correction of the maxillofacial skeletal deformities associated with cleidocranial dysplasia is presented. The common bony abnormalities are discussed, and the combined surgical and orthodontic management over an 8-year period is outlined.