Intraoral monocortical miniplating of mandible fractures.

OBJECTIVE: Intraoral monocortical miniplate fixation of mandibular fractures provides simultaneous visualization of the fracture and occlusal relation, while almost eliminating external incisions and potential compromise of the marginal mandibular nerve. We sought to analyze the outcome of our patients treated with this technique and compare this with literature standards for mandible fracture repair outcome. DESIGN: A retrospective analysis of outcomes for a case series. SETTING: All treatment performed in inner city, level 1 or 2 trauma rated, teaching hospitals. PATIENTS: During a 5-year period, 287 patients with 499 mandible fractures were treated with intraoral miniplates. Follow-up criteria was available for a retrospective analysis of 246 patients with 432 fractures of the mandible. INTERVENTION: Intraoral monocortical plating techniques were used to treat 313 of these 432 mandibular fractures. MAIN OUTCOME MEASURES: All complications of bone union, occlusion, wound infection, and dehiscence were graded and tabulated. RESULTS: On analysis of the miniplated fractures, 1.2% of the patients had delayed union, 0.4% had non-union, 6.5% had postoperative wound infection develop, and 4.1% had varying degrees of malunion. Complication rates are comparable with most reported studies of bicortical and monocortical plating of mandible fractures. CONCLUSIONS: Monocortical miniplate fixation is a reliable method of providing rigid fixation. It offers a reasonable alternative to bicortical plating in most mandible fractures.

Effect of a bioresorbable film on regeneration of cranial bone.

Regeneration of cranial bone is usually accomplished with autografts, banked bone, or both. The effect also may be obtained by using a properly engineered alloplastic barrier. Our group assessed histomorphometrically the capacity of a bioresorbable film to promote repair of cranial bone in critical-sized defects in 50 rabbits divided over four time periods (4, 8, 16, and 24 weeks). A single circular defect 15 mm in diameter was prepared in each rabbit and either covered with films of polylactic acid (21 mm in diameter, 150 microns thick) durally and pericranially or left untreated. Only after 24 weeks was there a significant difference (p < or = 0.05) between defects covered with polylactic acid films and those untreated. We conclude that after shorter periods, regardless of covering, prolapse of soft tissue into defects prevented osseous regeneration. We speculate that at 24 weeks, defects treated with films generated new bone as a result of changes in the local milieu conducive to osteoblastic expression.

Modification of inflammatory processes by phenobarbital in rats.

Enzyme-inducing drugs such as phenobarbital (PB) increase serum concentrations of an acute-phase protein, alpha 1-acid glycoprotein (AGP), in man, dogs, and rats via an unknown mechanism. We studied the effects of PB on components of an acute inflammatory reaction in rats in order to determine if PB acts only on this biological marker of inflammation or is capable of altering the clinical course of inflammatory processes. Local carrageenan injection induces a similar time-dependent plantar edema and increases serum AGP levels in Sprague-Dawley (SD) and Dark Agouti (DA) rats. Pretreatment with PB for seven days modified neither parameter in SD rats while plantar edema was aggravated and serum AGP levels were increased in DA rats. The sedative-hypnotic properties of PB were not involved, since a single administration of this drug had no action in DA rats. On the other hand, chronic PB administration reduced the severity of an autoimmune disease, type II collagen-induced arthritis, in DA rats. These data indicate that PB, a potent inducer a cytochrome P-450-dependent enzymes, modifies the course of the inflammatory process. Preliminary results with macrophage transfer experiments suggest that this response to PB could be mediated by stimulated macrophages.

Invasive Chrysosporium infection of the nose and paranasal sinuses in an immunocompromised host.

Aggressive fungal rhinosinusitis with Chrysosporium sp. occurred in a patient with acute lymphocytic leukemia. The infecting organism is an exceedingly rare human pathogen. Usually, human chrysosporial infections are mild and unmarked by symptoms. Most case reports appear in the pathology literature and describe the incidental finding of adiaspores in the pulmonary parenchyma at autopsy. Clinical disease from active growth of chrysosporial mycelia in human tissues has been noted on a porcine aortic valve prosthesis and in a tibial abscess. Hyphal elements were not recovered from any other body parts of these patients. Histopathologic and microbiologic studies permitted the identification of this rarely encountered organism. Our patient experienced systemic spread of Chrysosporium organisms. Treatment of this pathogen is the same as for other opportunistic fungal infections.

Monocortical miniplate fixation of mandibular angle fractures.

Noncompression monocortical miniplate fixation of mandibular fractures has become a reliable method of providing rigid fixation and eliminating the need for intermaxillary fixation. Recent studies, using a variety of internal fixation techniques, have described high complication rates at the mandibular angle. This article compares the use of one miniplate vs two miniplates in treatment of angle fractures. Since September 1985, 61 patients with 63 mandibular angle fractures have been treated with miniplates. Forty-four fractures were fixed with two miniplates. Six complications (3.1%) occurred, five of which were in the one-miniplate group. The complication rate in the double-miniplate group is the lowest reported of any plating technique. The use of two miniplates has proved to be an effective method of treating mandibular angle fractures.

Effect of repetitive lidocaine infusion on peripheral nerve.

Neurotoxicity in rat tibial nerve was assessed following injections of lidocaine through implanted catheters. Doses of 1 to 4% lidocaine in volumes sufficient to inhibit motor nerve function, were infused three times a day for 3 days. When 4% lidocaine was infused into a Silastic cuff surrounding the sciatic nerve, all function was lost and there was considerable nerve fiber degeneration. When 4% lidocaine was infused within the muscle pocket surrounding the nerve, but at some distance from the nerve, there was no measurable permanent loss of motor function, but occasional nerve fiber degeneration. In contrast, 1% lidocaine appeared to cause no neurotoxicity, even when infused within a surrounding cuff. In addition, 1% lidocaine injection did not cause damage to the underlying muscle. Therefore, intermittent nerve block with low concentrations of lidocaine appears to be nontoxic to nerve and muscle when administered during 3 days. However, long-term studies are needed before clinical usage can be considered, because there is the potential for nerve and muscle damage.