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This study examines the histologic and biochemical features of wound healing in a cleft lip model in the mid-third-trimester fetal rabbit. At days 1, 2, and 4 after the procedure, control, unrepaired, and repaired fetal heads were obtained, sectioned, and stained for histologic examination. The localization of hyaluronic acid in the wound was documented using a cartilage-derived hyaluronic acid-binding protein. In both repaired and unrepaired wounds, the fetal cleft healed without inflammatory cell infiltration or scar formation. Six months after birth, the repaired cleft showed complete regeneration of muscle across the wound and the collagen fibers were of normal density and orientation. Decreased hyaluronic acid deposition was observed in unrepaired clefts as compared with adjacent tissue; no such difference was detected in repaired clefts. Our findings support the hypothesis that a cleft lip repaired in utero heals without the scarring that accompanies postnatal repair. This may explain the lack of maxillary growth restriction after in utero cleft lip repair.

Twelve adults with maxillary width discrepancy of greater than 5 mm were treated by surgically assisted rapid maxillary expansion. The procedure consisted of bilateral zygomatic buttress and midpalatal osteotomies combined with the use of a tooth-borne orthopedic device postoperatively. Mean palatal expansion of 7.5 mm (range of 6 to 13 mm), measured in the first molar region, was achieved within 3 weeks in all patients. Expansion remained stable during the 12-month study period, with a mean relapse for the entire group of 0.88 +/- 0.48 mm. Morbidity was limited to mild postoperative discomfort. The results of this preliminary study indicated that surgically assisted rapid maxillary expansion is a safe, simple, and reliable procedure for achieving a permanent increase in skeletal maxillary width in adults. Further study is necessary to document the three-dimensional movements of the maxillary segments and long-term stability of the skeletal and dental changes.

The bicoronal scalp flap provides an excellent approach to the temporomandibular joint, particularly in cases where bilateral operation is required. It is also indicated when wide exposure is required and when previous surgery may make more conventional techniques difficult. In this report, the anatomy and indications for this approach are reviewed, the operative technique is described and complications are discussed.

The purpose of this study was to determine factors predictive of clinical outcome for pediatric patients with maxillofacial infections. Using linear logistic regression, four important variables, age, admission temperature, admission white blood cell count, and source of infection, were identified. Relevant study variables were abstracted from the records of all children less than 15 years old admitted to San Francisco General Hospital (SFGH) with facial infections between 1982 and 1986 (n = 105). An unfavorable clinical outcome was defined as a length of hospital stay (LOS) greater than or equal to 4 days and/or the need for an operation to resolve the infection. A favorable outcome was a LOS less than 4 days and no operation. To develop and validate the linear logistic model, the original group of patients (n = 105) was divided into index and validation sets. The index set was created by randomly selecting 80 of the original patients. The model was then applied to a validation set of the 25 remaining children. The model predicted that 13.95 of the patients in the validation set would have an unfavorable outcome. The actual number of unfavorable outcomes was 16. To further test the model's validity, a third data set was collected. It was composed of pediatric patients admitted to SFGH between January 1, 1987 and June 30, 1989 (n = 24). The model predicted that 15.99 of these patients would have an unfavorable outcome; 17 patients actually did have an unfavorable outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

It has been previously shown that osteoinduction by demineralized bone powder (DBP) in the rat decreases as the age of the recipient animal increases. In the present study, the effects of age on osteoinduction by DBP were evaluated in the rat by varying the age of the donor and the recipient animal. Cartilage and bone formation in subcutaneous pouches was assessed using a histologic grading technique in which a composite score was derived from analysis of multiple histologic sections from each specimen. The results confirm the previously reported decrease in osteoinduction in middle-aged adult animals compared with younger ones. However, DBP prepared from middle-aged adult rats was more inductive than that prepared from either prepubertal or young postpubertal animals. The latter result contradicts the widely held belief that demineralized bone matrix from younger animals is more inductive than that from older ones. This finding may help to further elucidate the mechanism of ectopic bone formation and lead to more inductive bone graft substitutes for human use.

We have previously described a model for in utero cleft lip repair in rabbits. Cleft lip and alveolus (CL) were created in fetal rabbits at 24 days gestation (term, 31 days). In this study, postnatal maxillary growth was evaluated in three groups of animals: 1) unoperated controls, 2) unrepaired CL, and 2) repaired CL. The animals were killed at 4, 12, and 26 weeks after birth. Direct cephalometry was performed on dry skulls to evaluate premaxillary width, anterior maxillary length and width, and posterior maxillary width. The results of this study indicate that rabbits that undergo an in utero CL procedure, with or without repair, exhibit no significant decrease in maxillary length and width when compared with controls.

Giant cell nuclear DNA, in 30 giant cell lesions of the jaws, was quantitated by computer-assisted image analysis. DNA content was then used to predict clinical behavior and outcome. Four.nuclei in each of 25 giant cells (total = 100 nuclei) were randomly selected and DNA content was quantitated by the LEITZ Texture-Analysis-System-Plus. DNA in nuclei of normal appearing stromal fibroblasts (n = 20) was similarly measured. DNA index was calculated as the mean nuclear DNA content of giant cells divided by mean DNA content of control fibroblasts. The mean DNA index of aggressive lesions (1.09, S. D. = 0.12) was not significantly different from that of non-aggressive lesions (1.18, S. D. = 0.15) (p = 0.093). The results indicate that nuclear DNA content of giant cells is not useful as a predictor of clinical behavior of giant-cell lesions of the jaws.

Demineralized bone powder (DBP) has been shown to induce osteogenesis in a variety of bone defects and extra-osseous sites. Previous investigations have been carried out in animal models which are time-consuming and expensive. We studied the effect of DBP on well-established populations of osteoblast and non-osteoblast-like cells in culture to establish an inexpensive, efficient and reliable assay for bone induction. DBP and BP (non-demineralized powder), of particle size 38-53 microns, were prepared from rat long bones. ROS (rat osteosarcoma) 17/2.8 and ROS 24/1 cell lines were subcultured weekly. For both 17/2.8 (well differentiated) and 24/1 (poorly differentiated) cells, proliferation, i.e. cell count, was significantly greater in DBP enriched medium when compared with control or medium with BP. Cell counts for wells with BP were no different from controls. The increased cell count in DBP-enriched medium was significant on days 2-5 (peak effect 2-3 days). Alkaline phosphatase production reached peak levels after day 3 when proliferation was beginning to taper off. In this study a consistent increase in osteoblast proliferation and alkaline phosphatase production under the influence of DBP was demonstrated. The tissue culture assay for proliferation must now be correlated with bone induction in vivo. In future, the method may be useful for investigating the mechanism of bone induction.

A management protocol for temporomandibular joint (TMJ) ankylosis consisting of 1) aggressive resection, 2) ipsilateral coronoidectomy, 3) contralateral coronoidectomy when necessary, 4) lining of the TMJ with temporalis fascia or cartilage, 5) reconstruction of the ramus with a costochondral graft, 6) rigid fixation, and 7) early mobilization and aggressive physiotherapy is presented. The protocol was retrospectively evaluated in the first 14 patients (18 involved TMJs) treated and followed postoperatively for at least 1 year. The facial asymmetries present in all unilateral cases remained corrected. The mean maximum postoperative interincisal opening at 1 year was 37.5 mm (292.36% mean increase), lateral excursions were present in 16 of 18 joints (vs 0 of 18 joints preoperatively), and pain was present in 2 of 18 joints (vs 13 of 18 preoperatively). The results of this study indicate that this protocol is effective for treatment of TMJ ankylosis.

This is a prospective study to evaluate therapeutic arthroscopy for internal derangement of the temporomandibular joint (TMJ). Fifty-nine patients with 76 abnormal joints were evaluated preoperatively for pain, noise, maximal incisal opening (MIO), and deviation on opening. Preoperative and postoperative magnetic resonance imaging (MRI) scans were obtained for 29 joints. Patients were treated by superior joint arthroscopy, lysis of adhesions, lavage, and steroid injection, along with preoperative and postoperative splint and physiotherapy. Pain, noise, and motion were evaluated at three time periods: 1) early (10 to 30 days); 2) intermediate (1 to 6 months); and 3) late (greater than 6 months). At early, intermediate, and late follow-up, increase in MIO was statistically significant (P less than .05). Noise did not return in the majority of patients. Disc position, evaluated by MRI, did not appear to change in 25 of 29 joints and did not correlate with clinical outcome. The results of this study indicate that TMJ arthroscopy is effective in reducing pain and increasing motion in patients with TMJ internal derangement.

This study evaluated the tissue reactions to two materials: ceramic hydroxyapatite (CHA), and a composite material of demineralized bone powder (DBP) and CHA (ratio of 4:1) in a collagen vehicle. The materials were tested in a subcutaneous pocket, a mandibular onlay, and in a calvarial onlay model. Specimens were evaluated histologically at 7, 10, 14, and 21 days postimplantation. Ceramic hydroxyapatite, implanted subcutaneously, elicited a fibrous response with minimal inflammation, but did not induce bone formation. In specimens of subcutaneously implanted composite material, induced bone was evident in association with the DBP. In CHA onlay specimens, there was a small amount of reactive bone extending from the host bone into the implant. In composite onlays, bone filled the entire body of the implant. The results of this study indicate that CHA particles were not osteoinductive in heterotopic sites and that osteoconductive ingrowth was minimal in onlays. Bone was induced by DBP even when mixed with CHA particles and implanted in subcutaneous and intraosseous sites. It was concluded that composite implants may provide a means of combining the osteoinductive properties of DBP with the bulk and structural support of osteoconductive CHA particles.

Recent clinical and experimental data indicate that fetal wound healing occurs without the accompanying inflammation and scar formation typical of postnatal wounds. The lack of scar tissue may have significant implications for craniomaxillofacial surgery. This report documents the development of a model for fetal cleft lip repair in rabbits. The survival rate for the first 47 fetuses was 76.6%.

The continuous refinement and further development of prenatal diagnostics and of anesthesiologic as well as operative techniques have rendered fetal surgery a point of major clinical interest. In view of the present clinical results of prenatal surgery in the human fetus, the question arises, if it is wise to include the correction of craniofacial malformations in the indications for intrauterine surgery and thus to allow the qualitative advantages of fetal wound healing patterns to be utilized. In the present experimental study an animal model using rabbits is presented, which allows successful intrauterine surgery of the craniofacial area.

This study used a prospective design to compare standard therapy (closed or open reduction with 4 weeks of maxillomandibular fixation) to rigid internal fixation (RIF) for the treatment of mandibular fractures. Ninety-two patients with 143 fractures were evaluated and treated. There was no statistically significant difference in the treatment results between the two groups, despite a bias in the distribution of study variables that favored the standard therapy.

Temporalis fascia, with a varying thickness of temporalis muscle, may be harvested as an axial flap based on the middle and deep temporal arteries and veins. The dependable blood supply, the proximity to the temporomandibular joint, and the ability to alter the arc of rotation by basing the flap inferiorly or posteriorly make this a versatile flap for lining the temporomandibular joint. In this report, the anatomy is reviewed, the harvesting technique is described, and multiple uses of the temporalis muscle-fascia flap in temporomandibular joint surgery are described.

Demineralized bone implants were placed as onlays in submucosal pockets on the edentulous segment of the rat mandible, between the incisor and posterior teeth. These implants, predictably, induced osteogenesis. The mass of induced bone and implant was united to the ridge by two weeks, and there was little or no resorption over a six-month follow-up period. This study suggests that demineralized bone implants may be useful for mandibular ridge augmentation.

A biologic classification based on clinical behavior and endothelial cell characteristics is used to divide vascular birthmarks into two groups: hemangiomas and vascular malformations. This system is applied to vascular anomalies of the maxillofacial region and is demonstrated with illustrative cases. The distinction between hemangioma and vascular malformation is important for maxillofacial surgeons because hemangiomas rarely affect bone, whereas malformations affect bone in 35% of cases.

Temporomandibular joint dysfunction is multifactorial in etiology. In many patients, psychological factors contribute to the development of symptoms. This is a retrospective study of 25 patients who had temporomandibular joint dysfunction and facial pain as an early sign of significant primary psychopathology. The diagnoses were: acute depression, manic-depressive illness, hysteria, and schizophrenia. Diagnosis of the underlying psychopathology and recognition of its role in the etiology of temporomandibular joint symptoms permitted more effective treatment.

Computed tomography was found to be useful in identifying complete, unilateral, fibro-osseous ankylosis of the temporomandibular joint in a case of mandibular hypomobility. The scan had increased sensitivity and reliability in studying hard and soft tissues of the TMJ and gave the patient less radiation exposure than conventional tomography or arthrotomography. The current report incorporates the CT scan into a radiographic protocol for the diagnosis of mandibular hypomobility and identifies situations in which conventional tomography can be omitted.

Temporomandibular joint dysfunction with myofascial pain, a well-known clinical disorder in adults, is reported in children. In a series of 400 patients, 40 children less than 16 years of age were seen. Of these pediatric patients, 35% had a reactive depression as primary psychopathology. The multifactorial nature of the disorder is described. The need to differentiate this syndrome from recurrent otitis media and other pain syndromes is emphasized. A combined medical, oral surgical, and psychiatric management program is outlined.

Chin trauma, mandibular fracture, and cervical spine injury are often progressive components of a single injury pattern. Knowledge of a commonly occurring sequence of damage in patients who have sustained minor head trauma helps to minimize diagnostic omissions and provides a rational basis for deciding how extensive the patient's evaluation should be. Chin laceration associated with underlying skeletal damage has been described previously, but its diagnostic significance seldom has been appreciated. This report describes representative patients with fractures of the cervical spine and of the mandible secondary to chin trauma and suggests a protocol for efficient diagnosis.

Based on our experience with 40 patients with hemifacial microsomia (first and second branchial arch deformity), we have developed a three-dimensional analytic approach to the skeletal deformity. The sagittal plane x-ray views (lateral cephalogram and panorex) demonstrate the anatomy of the temporomandibular joint as well as the shape and height of the mandibular rami. The frontal plane is demonstrated by the anterio-posterior (A-P) cephalogram, which shows the discrepancy in ramus height and the abnormal arc of mandibular rotation toward the affected side. The transverse plane is evaluated with a submental vertex radiograph, which shows the shape of the mandibular body and medial displacement of the temporomandibular joint. Three-plane radiographic analysis demonstrates the total anatomic distortion and the abnormal growth vectors. We hypothesize that abnormal mandibular growth is of primary importance in this deformity. Application of this analysis has influenced the timing of intervention and the design of corrective procedures.

Draining skin lesions in the face are a common problem in head and neck surgery. The differential diagnosis includes various types of skin infection as well as infected tumor. Often overlooked is the possibility of a chronically infected tooth. The patients in this report illustrate cutaneous drainage in five locations from different teeth. The anatomic basis for these drainage tracts and the diagnostic workup have been described. We advise that these patients have a dental evaluation.

Our experience over the past 25 years leads us to conclude that hemifacial microsomia is a progressive skeletal and soft-tissue deformity with the earliest skeletal manifestations in the mandible. We find that not only does the mandibular asymmetry become worse with time, but as the contralateral side grows, the deformed mandible also increases ipsilateral secondary deformation of the maxilla, nose, and orbit. We also find that there is virtually no "catch up" growth on the affected side of the face and that these patients always become more deformed with age. The psychological problems also increase with time and progression of the facial deformity. Based on our experience with correction of end-stage deformities, we now treat these patients at the earliest possible age, as determined by the patient's skeletal classification. We treat the mandible first in the hope that this repositioning in a more physiologic position will unlock the growth potential of the adjacent structures, minimize secondary deformity, and improve function and appearance to the greater benefit of the skeletal and psychological growth of the patient.

Accurate assessment of facial skeletal growth remains a major problem in craniomaxillofacial surgery. Current methods include 1) comparisons of chronologic age with growth histories of the patient and the family, 2) hand-wrist radiographs compared with a standard, and 3) serial cephalometric radiographs. Uptake of technetium-99m methylene diphosphonate into bone is a reflection of current metabolic activity and blood flow. Therefore, scintigraphy with this radiopharmaceutical might serve as a good method of assessing skeletal growth. Thirty-four patients, ranging in age from 15 months to 22 years, who were undergoing skeletal scintigrams for acute pathologic conditions of the extremities, were used to develop standards of uptake based on age and skeletal maturation. The results indicate that skeletal scintigraphy may be useful in evaluation of mandibular growth.

A model for the diagnosis and treatment of temporomandibular joint dysfunction and facial pain in children is presented. Emphasis is placed on systematic assessment of physical, psychologic, and behavioral factors when conservative medical therapy is inadequate for symptom relief. The model represents a multidisciplinary approach to patient care which is described through case presentations. The results of research on the incidence of primary psychopathology in 53 children and 322 adults evaluated during a 3-year period for temporomandibular joint dysfunction and facial pain are also presented. It was found that children were more likely to be psychiatrically impaired (25%) than adults (7%). Children had a variety of psychiatric diagnoses including depression, conversion and adjustment disorders, overanxious behavior, and anorexia nervosa. The benefits of a multidisciplinary approach are discussed in terms of the efficacy of this coordinated treatment effort in ameliorating symptoms.

Uptake of a bone-seeking radiopharmaceutical is correlated with growth changes in the rat mandible. Uptake was highest in newborn rats, decreasing with increasing age.

In 1973 methods for diagnosing and treating zygomatic complex fractures were reviewed, with emphasis on the lateral eyebrow incision for access to the zygomaticofrontal region. The following clinical update reviews alternative approaches to the zygomatic complex (coronal incision, upper eyelid incision), and current concepts of treatment for acute injuries and late deformities secondary to malunion.

In studying macroglossia, no one has described normal tongue size or applied direct measurement to the pathologically enlarged tongue. Since macroglossia is primarily a condition that requires treatment on a symptomatic basis, definition of the problem in clinical terms is the most useful form for the practitioner. Based on published reports and our clinical experience, a classification scheme for macroglossia has been formulated. The concept of true macroglossia and relative macroglossia form a framework that categorizes acquired and congenital forms of tongue enlargement. True macroglossia exists when histologic abnormalities correlate with the clinical findings of tongue enlargement. Vascular malformations, muscular enlargement, and tumors are the most common forms of true macroglossia. Relative macroglossia includes those cases of apparent tongue enlargement in which the histology does not provide a pathologic explanation. Down's syndrome is a commonly quoted cause for tongue enlargement and is a form of relative macroglossia. The development of this classification system establishes an approach and common terminology on which therapy, research, and communication can be based.

Mandibular hypomobility may be the result of a number of intra- and extra-articular conditions. Its treatment, predicated on an accurate diagnosis, varies from minor manipulative maneuvers to several surgical procedures. The applicability of coronoidectomy, in certain conditions, has become increasingly important.

This report illustrates the spread of odontogenic infection to the orbit and the usefulness of the CT scan for the differential diagnosis of periorbital vs orbital cellulitis and abscess. It shows the necessity for close follow-up of patients with odontogenic infection so that life-endangering complications may be treated promptly. Finally, this patient illustrates the fact that, in some cases, a dental infection may be so virulent that drainage through the tooth and antibiotics do not provide control. Tooth removal and prompt incision and drainage are required for adequate treatment.

Demineralised bone implants were used for cranio-maxillofacial reconstruction and construction in 34 patients, 28 with congenital deformities and 6 with acquired defects. The patients' ages ranged from 15 months to 59 years (mean 18 years). In 33 cases, the implants were obtained from cadaver femurs; in 1 case, the implant was prepared from the patient's own skull. Early healing was assessed by clinical and radiographic examination and, when appropriate, by biopsy. Longer follow-up will be required to determine whether resorption has been avoided. The clinical advantages are rapid union, healing of large defects, avoidance of harvesting procedures, and the potentially unlimited supply of banked material.

The most difficult problem in the treatment of ankylosis of the temporomandibular joint is to maintain the immediate jaw mobility gained by surgery over a long period of time. This article describes a spring-loaded device for physiotherapy which provides an active opening force from the mandibular splint, distributed against a splint on the maxillary teeth and hard palate. Because the force is continuous and broadly distributed, patients have been able to exercise with minimal discomfort, and they have been able to maintain their initial postoperative mobility.

Nineteen of 30 patients who had midface advancement procedures between 1972 and 1980 had sufficient cephalometric data to be included in this retrospective study. The position of the midface in relation to the cranium and mandible was evaluated immediately postoperatively and for a period of 2 to 11 years (mean 5.8 years). At 1 year, midface position after LeFort III advancement was stable in 12 of 19 patients. Of these 12 patients, 8 showed some evidence of downward and/or forward movement of the midface. The remaining 7 patients showed a minor degree of midface relapse in the first year of follow-up. In 15 of 19 patients, at 2 years or more postoperatively, the final position of the midface was either at, anterior to, or inferior to its immediate postoperative location. Correction of exorbitism remained stable in all but one patient, who required a second advancement of the orbital segment. Three patients required subsequent LeFort I osteotomy to correct class III occlusion. Prognathism was determined to be secondary to mandibular growth, not midface relapse.

Based on longitudinal observation of more than 80 patients, we concluded that mandibular hypoplasia is the earliest skeletal manifestation of hemifacial microsomia. The clinical defect becomes worse with time as a result of continued asymmetric growth and progressive secondary deformation of the midface. We hypothesize that midface growth is restricted by the hypoplastic mandible. Therefore, early elongation of the mandible should result in a more symmetrical growth pattern by eliminating mandibular restriction and creating a space for vertical midface growth.

This study evaluated the effects of the California mandatory seat belt law on prevention of motor vehicle accident (MVA)-related maxillofacial injuries. The records of 950 MVA-related injury victims treated at San Francisco General Hospital during comparable 3-month periods in 1985 (451) and 1986 (499) were reviewed to assess the effect of seat belt legislation on reduction of maxillofacial trauma. No significant difference was found in the injury severity scores between the two study periods. In addition, this study did not confirm the reported beneficial effect of seat belt legislation on reduction of MVA-related facial injuries in California. This finding was attributed to poor compliance with the law (50.3% compliance rate).

We have analyzed 404 patients with a wide variety of maxillary and craniofacial deformities. These do not include head and neck cancer patients as generally defined. Satisfaction has been high as judged by the patients, surgeons and psychiatrists. The complication rate has been significant, approximately 30%, the most common being infection or loss of bone grafts. As experience accumulated, the concept of earlier operative intervention has emerged as an aid in unlocking growth potential, diminishing secondary deformity and improving the development of body image.

Morbidity following 104 bone graft harvesting operations (60 iliac, 44 rib) in 72 patients is documented. Early morbidity of iliac donor sites was found, as expected, to be far greater than that of rib donor sites. However, long-term follow-up reveals that while hip symptoms largely resolve, a significant number of chest-wall sites cause persistent, unpleasant pain. Technical ways of minimizing problems are also discussed. When procuring an iliac graft, a lateral skin incision and a medial bony approach are used if possible. If full-thickness ilium is required, the crest should be left intact or raised and replaced as a trapdoor .

Hemifacial microsomia (HFM) is not a fixed dysmorphic deformity, but rather a progressive, complex deformation, involving the soft tissues and skeletal structures derived from the first and second branchial arches. Secondary growth distortion is seen particularly in the failure of midface growth, because of inadequate mandibular vertical growth on the involved side. Based on this concept of a dysfunctional matrix, we treat HFM in childhood according to the severity of the mandibular hypoplasia. In the type I and type IIA children seen in the deciduous stage, we recommend use of an activator or functional appliance. The more severe type IIB and type III children with absent structures need early construction of the mandibular ramus, glenoid fossa, and temporomandibular joint. In so doing, we convert the severely hypoplastic mandible into a more symmetric and functional type IIA status. Correction of the mandible appears to maximize potential growth and minimize the documented secondary distortion in the maxilla. Preliminary study confirms that early correction minimizes the need for maxillary and orbital osteotomies as these patients enter adulthood. We have briefly outlined our approach to soft-tissue hypoplasia and neuromuscular deficiency in HMF. Further refinements are needed in these areas.

Midface advancement by Le Fort III osteotomy is a common procedure in craniofacial surgery. However, little data exist concerning the effect of midface advancement on mandibular growth. This is a retrospective study of 38 patients from two craniofacial centers who had Le Fort III osteotomy. The aims of this investigation were to document the size and shape of the mandible in Crouzon and Apert syndromes and to determine the effect on these parameters of downward and forward movement of the midface. The syndrome patients had increased gonial angle, increased MP-SN, increased ramus height, and increased ratio of ramus height to body length when compared with normal standards. Patients operated during growth and those operated when growth was completed had similar mandibular size and shape indicating that Le Fort III osteotomy had no measurable effect on these parameters. Inclination of the mandible to the anterior cranial base was increased by the operation and remained unchanged during the follow-up period. The results of this study indicate that the size and morphology of the mandible are similar in Crouzon and Apert syndromes. The pattern of growth is more vertical in the syndrome patients than in normals. Le Fort III osteotomy in growing children does not result in altered mandibular size and shape despite backward rotation of the mandible as a result of midface advancement.

Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement.

A shortened prophylactic regimen of antibiotics for maxillofacial and craniofacial surgery is evaluated. Eighty-five patients were divided into two groups on the basis of the type of incision used. Forty-nine patients undergoing intraoral procedures received penicillin perioperatively and were given one postoperative dose (regimen A). Thirty-six patients undergoing extraoral or combined intraoral and extraoral procedures received penicillin and oxacillin perioperatively, with nine receiving one postoperative dose and 27 receiving an average of seven postoperative doses (regimen B). One infection was observed in the regimen A group, and three were observed in the regimen B group. This infection rate compares favorably to that encountered in the authors' previously reported study on longer prophylactic courses of antibiotics.