Propofol and fentanyl compared with midazolam and fentanyl during third molar surgery.

PURPOSE: The purpose of this study was to measure the safety and efficacy of propofol combined with fentanyl as sedative agents during third molar outpatient surgery. PATIENTS AND METHODS: A double-blind, prospective, randomized clinical trial involving 57 patients undergoing removal of third molars under intravenous sedation between November 1994 and December 1995 was performed. Patients randomly received either propofol and fentanyl (P + F, th = 24) or midazolam and fentanyl (M + F, M = 33). Patient demographics, Corah anxiety scores, and physiologic parameters were determined preoperatively. All medications were titrated to the same clinical end point for sedation. Intraoperative physiologic parameters, cooperation, alertness, and pain scores were assessed. Postoperative recovery and degree of amnesia also were determined. RESULTS: There were no significant differences in either patient demographics or surgical characteristics between groups. The P + F group was significantly less cooperative than the M + F group. Pain during injection of propofol was a significant adverse side effect. Both groups experienced a small percentage of apneic episodes, but mechanical ventilation was never required. There were no differences in recovery between groups as measured by the Treiger dot test and psychomotor recovery scores. The degree of anterograde amnesia was greater for the M + F group, although the difference was not statistically significant. Sedation was rated good to excellent by the patient, surgeon, and observer, and there were no statistically significant differences between groups. CONCLUSION: Propofol appears to be a safe and efficacious drug for use during outpatient oral surgical procedures.

Torque and pullout analysis of six currently available self-tapping and "emergency" screws.

Insertional torque (IT), stripping torque (ST), and uniaxial pullout tests were performed to evaluate the effectiveness of six screw systems (Wurzburg, Techmedica, Synthes, Timesh, Steinhouser, Luhr) in thin porcine rib. The Timesh 2.2-mm self-tapping screw produced the largest insertional and stripping torque of all systems tested as well as the largest difference between the insertional and stripping torque. The Timesh emergency screw also had the largest insertional and stripping torque as well as the largest difference between the insertional and stripping torque. In pullout tests, the Timesh screw was found to be the most retentive. The overall data indicated that the ideal self-tapping screw should have the largest difference possible between drill size and external diameter, a channel, and at least three self-tapping threads for maximum retention.

Comparison between uniaxial pull-out tests and torque measurement of 2.0-mm self-tapping screws.

This study investigates the retentive capacity of 2.0-mm self-tapping screws in porcine rib utilizing axial pull-out tests as well as torque measurements of insertion and stripping. These techniques have been performed independently; this analysis assesses the association between pull-out and torque values. The Goodman-Kruskel correlation coefficient between pull-out and insertional torque is 0.13, while the correlation between pull-out and stripping torque is 0.21. Partial correlation indexes control the thickness of bone, a confounding factor. Nonparametric analysis of covariance showed no significant difference between insertion of screws and pull-out of the screws, but stripping versus pull-out test was significant. Given these findings, it appears that insertional torque may be used as an alternative technique for screw retention analysis. Because insertional torque tests can be conducted in the operating room, results of clinical studies can be compared to laboratory analyses.

Evaluation of emergency screws in nonstripped pilot holes in bone.

Clinicians continue to search for a rigid internal fixation system that will remain stable in thin bone, such as that found in the lateral walls of the maxilla. Insertion of a large-diameter screw in a pilot hole has been suggested to improve screw retention. This study evaluates insertional and stripping torque of six emergency screw systems placed in nonstripped pilot holes of porcine rib (thickness < or = 2 mm). The Timesh and Synthes emergency screws did not properly fit into the nonstripped pilot holes. The Techmedica emergency screw was the most retentive. The Luhr, Wurzburg, and Steinhouser emergency screws were less retentive. The Techmedica emergency screw had the greatest stripping torque in nonstripped pilot holes, but it was not significantly greater when compared to the stripping torque of identical screws placed in 2.0-mm stripped holes. The Luhr, Wurzburg, and Steinhouser emergency screws placed in 1.5-mm pilot holes had significantly less stripping torque when compared to identical screws placed in 2.0-mm stripped holes. It appears the Luhr, Wurzberg, and Steinhouser 2.0-mm self-tapping screws have a greater stripping torque than the corresponding emergency screw when placed in 1.5-mm pilot holes.

Cortical thickness in human mandibles: clinical relevance to the sagittal split ramus osteotomy.

Human cadaver hemimandibles were subjected to sagittal split ramus osteotomy, and the cortical thickness of each mandible was then measured in several areas. A measurable difference in morphology was found in the proximal segment of the mandible. Because cortical bone thickness is directly related to bone-screw holding strength, these results have important implications for the use of rigid internal fixation. The results suggested that the areas that coincide with the most anterior and superior extent of the osteotomy would be the ideal locations for screw placement.

The effect of repetitive screw hole use on the retentive strength of pretapped and self-tapped screws.

Multiple systems for internal screw fixation are presently in use in oral and maxillofacial surgery. These systems differ in screw diameter, material, and design. This study evaluated the uniaxial pullout strength of five screw systems. Two-millimeter, 2.7-mm, and 3.5-mm screws were initially evaluated for pullout strength. Pretapped and self-tapped screws were then inserted into the same hole multiple times before pullout testing. Results of pullout testing revealed no significant difference in pullout strength of pretapped and self-tapped screws of equal diameter (P greater than .05). Increased screw diameter produced increased pullout strength. No significant difference in pullout strength was noted in pretapped or self-tapped screws inserted into the same hole one, two, or three times before pullout testing (P greater than .05).

Internal screw fixation: comparison of placement pattern and rigidity.

Multiple screw placement patterns and techniques have been described for fixation of the sagittal split ramus osteotomy. This study evaluated transverse strength (rigidity) of six groups of simulated sagittal osteotomies fixed with different screw patterns and placement techniques. Osteotomies fixed with screws placed in an inverted L pattern were significantly more rigid than those fixed with screws placed in a linear pattern or K-wires placed in a triangular pattern (P less than .05). No significant difference in rigidity was noted between compression and bicortical screws placed in identical patterns.

Uniaxial pullout evaluation of internal screw fixation.

Multiple techniques of internal screw fixation are being used in clinical oral and maxillofacial surgery. This study evaluated the uniaxial pull-out strength of five commonly used screws and Kirschner pins placed by five different techniques. The pull-out strength of the Kirschner pins was significantly less (P greater than .0001) than that of the screws. The screw techniques did not differ significantly.

Comparison of the use of nalbuphine and fentanyl during third molar surgery.

In a double-blind, randomized plan of drug administration, nalbuphine, fentanyl, and a placebo were compared for efficacy in sedation and analgesia during third molar removal. Fifty-eight patients participated in this study. Using accepted intravenous sedation and surgical techniques, fentanyl and nalbuphine were found to be better than placebo for anxiety and pain control in third molar surgery. Fentanyl had a longer duration of pain relief postoperatively than did nalbuphine. The study confirmed the need for a narcotic supplement to sedation techniques for third molar surgery.

Evaluation of hydroxylapatite particles in repair of alveolar clefts in dogs.

Twelve adult mongrel dogs were used to evaluate the use of hydroxylapatite (HA) in the closure of alveolar clefts. Bilateral alveolar clefts were surgically created in each animal. After healing, they were implanted randomly with either HA or particulate cancellous bone and marrow (PCBM). The results were evaluated clinically, radiographically, and histologically for healing, acceptance of the implant, closure of the fistula, and bony ingrowth. The results show that HA was as successful in closure of the fistulas and re-establishing an intact maxilla as PCBM. Minimal osteoid and bone was interspersed in the HA implant sites. No complications resulted from the HA graft.

Ultrasound as a diagnostic aid in maxillofacial surgery. Report of a case.

Ultrasonographic examination of masses in the neck can be a valuable diagnostic aid. It has the advantages of being noninvasive, rapid, easily repeated, and relatively inexpensive. Ultrasound is also a particularly convenient means of localizing lesions for percutaneous biopsy and for serially monitoring the response of a lesion to therapy. As experience increases and equipment improves, ultrasound will gain an even greater role as a diagnostic aid. A case is reported in which a mucus-retention phenomenon was evaluated, managed, and followed with the aid of B-scan ultrasonographic and real-time imaging.

Nursing care of patients in intermaxillary fixation.

Often patients in IMF are healthier, tend to be more independent, and have shorter hospital stays than many patients hospitalized for other reasons. This is by no means any indication that they do not require close assessment and skilled nursing care. While recovering from anesthesia, airway obstruction and vomiting are real dangers. Although wire cutters are a necessary safety precaution and a part of the legal standard of practice, nurses and patients should not rely solely on them in the incidence of shortness of breath or vomiting. Nurses and patients should know the proper technique for clearing the mouth and airway of a patient in IMF. Hemorrhage evaluation and secretion control also require skilled observation and assistance by the nurse. Patients in IMF benefit from a decrease in anxiety levels when they are educated in airway clearance, secretion control, comfort measures, and diet. The nursing care of patients in IMF is rewarding and challenging for many areas of nursing.

Evaluation of metacarpal bone plates in the mandibular fracture.

Of 1587 mandibular fractures, 75 (4.7 per cent) were treated by open reduction with metacarpal bone plates. The plated fractures were reviewed and evaluated for failure. Seventeen plates of the 96 placed were removed (17.7 per cent). Infection was the major cause of failure (9.4 per cent). Operator error played a role in the failure of eight out of 17 plates (47.1 per cent). Various aspects were studied in order to find the significant factors present, and these are discussed.

Alternative stabilization of the maxilla during simultaneous jaw-mobilization procedures.

A technique involving a bone plating system for stabilization of the maxilla in simultaneous surgery on both upper and lower jaws is presented. The alternatives to this method of stabilization are discussed. The literature on the use of miniplates in midface surgery is reviewed. The use and adaptation of readily available orthopedic metacarpal plates is discussed. Familiarization with this system is recommended.

Revascularization and healing of onlay particulate allogeneic bone grafts in primates.

Particle size of allogeneic bone grafts was investigated to determine its effect on revascularization and healing. Freeze-dried chips of different sizes were placed on the monkey lateral mandibular cortex, and the subsequent healing and revascularization were studied by histologic, autoradiographic, and microangiographic techniques. It appears that allogeneic bone is a reasonable substitute for autologous bone in mandibular ridge augmentation procedures.