Predicting postoperative nausea and vomiting in patients undergoing oral and maxillofacial surgery.

A common predictive measure of postoperative nausea and vomiting (PONV) is the Apfel score. Although tested in many different operations, it has not been tested extensively in oral and maxillofacial surgery (OMFS). This study was designed to determine whether it applied to OMFS and whether there were other factors in this population that would improve its accuracy. A retrospective chart review was carried out on a randomly selected group of patients who had OMFS during a 10-month period. In addition to the Apfel score risk factors, PONV data were collected in relation to type of anesthetic induction and maintenance, type of surgery, use of maxillomandibular fixation (MMF), use of opioids, and anesthesia and surgery times. One-hundred and sixty-seven patients were included in the analysis; 24% had nausea and 11% had nausea and vomiting. Patients who had orthognathic or temporomandibular joint surgery had the highest rate of PONV. Young age, anesthesia and operation time, and use of MMF were also associated with increased PONV. Adding age, MMF or limited postoperative mouth opening, and surgery type to the Apfel score should make it more predictive in OMFS.

Opinions of American and Swedish orthodontists about the role of erupting third molars as a cause of dental crowding.

OBJECTIVE: To compare the opinions of Swedish orthodontists and American orthodontists regarding the association between third molar eruption and dental crowding. MATERIALS AND METHODS: A survey was distributed to Swedish orthodontists (n = 230) asking their views on the force exerted by erupting third molars, its relationship to crowding, and their recommendations for prophylactic removal. Results were compared with those from a similar study conducted in the United States. Chi square analysis was used to determine differences in responses to questions between Swedish and American orthodontists. P < or = .05 was considered significant. RESULTS: Both Swedish and American orthodontists believed that lower third molars were more likely than upper third molars to cause force (65% and 58% for Swedish and American orthodontists, respectively) and crowding (42% and 40%, respectively). No statistically significant differences were seen between the answers of American and Swedish orthodontists regarding the role of upper and lower third molars in causing crowding. Although only 18% of Swedish orthodontists "generally" or "sometimes" recommended prophylactic removal of mandibular third molars, 36% of American orthodontists "generally" or "sometimes" recommended removal (P < .0001). CONCLUSIONS: Most orthodontists in the United States and Sweden do believe that erupting lower third molars exert an anterior force; however, they also believe that these teeth "rarely" or "never" cause crowding of the dentition. The reason that more American orthodontists recommend prophylactic removal of mandibular third molars remains unexplained.

Comparison of the stress direction on the TMJ in patients with class I, II, and III skeletal relationships.

OBJECTIVE: To assess the relationship between skeletal morphology and stress direction on the temporomandibular joint (TMJ) by a two-dimensional rigid body spring model (RBSM). DESIGN: Lateral cephalograms were analyzed and the information was processed with a fortran analysis program. SETTING AND SAMPLE POPULATION: The subjects were 149 patients (54 men and 95 women, mean age 21.8 +/- 5.9 years) from Kanazawa University Hospital and the School of Dentistry, Virginia Commonwealth University. Of the 149 cases, 48 were skeletal class I, 54 were class II, and 47 were class III. The patients had no TMJ symptoms or abnormalities. OUTCOME MEASURE: The force vector on the condyle, its direction (Ph angle), the degree of the vector (Ph) and the displacement vector (u, v), and the rotational angle (theta) of the mandibular body were calculated by RBSM. RESULTS: The direction of the force vector (Ph angle) on the condyle was 24.83 degrees +/- 4.67 degrees in the class II group, 21.04 degrees +/- 5.59 degrees in the class I group, and 19.58 +/- 7.57 degrees in the class III group. The Ph angle of the class II group was significantly larger than those of the class I and III groups (p < 0.05). CONCLUSIONS: This study suggests that differences in skeletal patterns induce differences in stress distribution on the TMJ; the morphology of the TMJ was also associated with stress direction and distribution on the condyle.

A comparative study of mandibular fractures in the United States and Turkey.

This study compared the data on mandibular fractures that occurred in a city in the United States and one in Turkey between 1991 and 2000. The 210 Turkish patients had 252 mandibular fractures, whereas the 665 US patients had 1042 mandibular fractures. Males accounted for 84% (560 patients) and females for 16% (105 patients) of the cases in the US. The male:female ratio was 5.5:1. In Turkey, males accounted for 76% (160 patients) and females for 24% (50 patients) of cases. The male:female ratio was 3.2:1. Assault (53.7%) was the most common cause of fracture in the US, whereas in Turkey the most common cause was a motor vehicle accident (36.2%). The most common site of mandibular fracture in the US was the angle (27.57%); in Turkey the most common site was the body (28.97%). Many of these variations may be related to socioeconomic, cultural and environmental differences between the two countries.

Depression, pain, exposure to stressful life events, and long-term outcomes in temporomandibular disorder patients.

PURPOSE: This study investigated the role of psychological factors in temporomandibular disorders (TMD). Orofacial pain patients' pretreatment levels of depression, disability caused by pain, and exposure to stressful life events were measured, and differences on these variables between temporomandibular joint (TMJ) disease patients and patients whose pain was of muscular origin (MPD) were evaluated. The use of these variables and patient diagnostic status in predicting response to treatment in a subsample of these patients was also evaluated. PATIENTS AND METHODS: Before undergoing treatment, 258 patients were administered the Beck Depression Inventory (BDI), the Pain Disability Index (PDI), and the Social Readjustment Rating Scale (SRRS). Follow-up data on pain disability, current level of pain, depression, and satisfaction with treatment were obtained on 48 of these patients who were contacted at varying intervals after completing treatment. RESULTS: BDI scores obtained at the outset of treatment were significantly elevated and were positively correlated with SRRS and PDI scores. MPD patients had higher SRRS, BDI depression, and PDI pain disability scores than TMJ patients, and differences between the 2 groups in pain disability were greatest in areas that are often sources of interpersonal stress. Among follow-up patients, PDI scores declined after treatment, with MPD patients showing greater decreases than TMJ patients. Independent of patients' diagnostic status, their pretreatment PDI scores were predictive of their pain level at follow-up and were inversely related to their degree of satisfaction with treatment at follow-up; their pretreatment BDI scores were predictive of their depression level at follow-up. CONCLUSIONS: The findings are consistent with previous research indicating a link between emotional dysfunction and TMD and are largely supportive of the conclusion that psychological factors play a more pronounced role when pain is of muscular origin. Promising behavioral interventions are available for TMD patients in whom psychological factors appear to be playing a significant role.

Upper lip asymmetry in adults during smiling.

PURPOSE: This study examined the incidence of upper lip asymmetry in adults while smiling. PATIENTS AND METHODS: Two-hundred ten students between the ages of 21 and 44 years were examined. Subjects determined to have an occlusal plane cant were eliminated from the study. Repeated smiles were then evaluated in the remaining subjects to check for upper lip asymmetry. RESULTS: Fifteen subjects were observed to have occlusal plane cants and were eliminated from the study. Of the remaining 195 subjects, 17 (8.7%) were found to have an asymmetrical smile secondary to canting of the upper lip. CONCLUSIONS: Although there was not a high incidence, the results of this study indicate there is clinically evident upper lip canting associated with smiling in the adult population that needs to be considered in patients undergoing orthognathic and cosmetic surgery.