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A surgical philosophy of orthognathic surgery is presented. It has evolved over an entire surgical career as orthognathic surgical goals have evolved to become primarily aesthetic. In this context, the occlusal result serves as a means of achieving the aesthetic ends. It relies on the physical examination, using qualitative concepts of facial appearance, to be the most important determinant of treatment plans. It makes a distinction between a quantitatively normal face and one that is visually well proportioned and emphasizes the attributes of the soft tissue. The emotional expression of the patient is also considered in treatment planning. By using surgical tactics that provide control of facial projection and height, this philosophy affords the surgeon an opportunity to manipulate the skeletal elements to the extent that one can simultaneously achieve a well-proportioned face and favorably influence the appearance of the soft tissues and facial countenance.

Orthognathic surgical planning should derive primarily from aesthetic considerations, and these should be based not on rigid cephalometric and anthropometric norms but on the surgeon's aesthetic sense. The historic goals of orthognathic surgery have addressed both stability and aesthetics. Stability relates to establishing a healthy, functional occlusion; aesthetic goals have focused on normalizing facial balance and proportions. With the advent of rigid fixation and bone graft substitutes, sacrificing facial aesthetics to attain stability and achieve a normal occlusion is no longer necessary. Orthognathic surgery now can be envisioned truly as aesthetic surgery.

It has been demonstrated previously that many individuals requesting chin enlargement have small or retruded mandibles. A weak chin may be only one aspect of this particular class II skeletal deformity, the other components being a procumbent, retrusive lower lip, excessive labiomental fold depth, and decreased to normal lower face height. To avoid unaesthetic results, the chin should not be advanced beyond the retrusive lower lip, the only component over which osseous genioplasty has no control. This may result in residual sagittal "weakness" of the lower face, for which visual compensation can be achieved by vertical overelongation of the chin. Thirty-two patients requesting chin enlargement presented with the aforementioned class II deformity. Twenty patients had decreased lower face height and 12 patients had normal lower face height. Preoperative soft-tissue cephalometric analysis documented physical findings. The extent of sagittal chin movement was planned to advance the soft-tissue pogonion no further than the lower lip. Vertical chin movement was intentionally designed to overelongate the lower face relative to the midface in all patients. Radiographs were repeated at a mean 8.2 months following surgery to document skeletal displacements. Mean chin advancement was a modest 4.2 mm (2- to 7-mm range), and chin vertical displacement was a mean 7.9 mm (5.5- to 9-mm range). All patients had residual sagittal disproportion of the pogonion relative to the subnasale (-7.6 mm mean) and newly created vertical disproportion with mean lower face heights of 69.8 mm compared with mean midface heights of 64 mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Patients afflicted with extreme degrees of mandibular micrognathia typically have vertically deficient rami as well as sagittally deficient mandibular bodies. This results in deficient posterior facial height, an obtuse gonial angle, excessively steep occlusal and mandibular planes, and a compensatory increase in anterior facial height. The entire maxillomandibular complex is overrotated in a clockwise direction. Standard orthognathic surgical correction fails to address this rotational deformity. As a consequence, the achieved projection of the lower face is inadequate, posterior facial height is further reduced, and occlusal and mandibular planes remain steep. Eleven patients with severe mandibular micrognathia underwent a surgical correction involving occlusal plane rotation to its normal orientation relative to Frankfort horizontal. This was accomplished by Le Fort I osteotomy to shorten the anterior maxilla (creating open bites in seven patients and making preexisting open bites worse in four patients) and sagittal split ramus osteotomies to advance and rotate the mandibular body counterclockwise, thus closing the surgically produced open bite. Counterclockwise rotation of the mandible afforded significantly greater sagittal displacement at the B point (mean 17 mm) than at the first molar (mean 10 mm) and produced adequate degrees of projection of the lower face when accompanied by a modest sliding genioplasty (mean 6.9 mm). Total advancement at the pogonion was a mean of 25.2 mm. In addition, posterior facial height was preserved, and mandibular and occlusal planes were normalized to mean angles of 27 and 10 degrees, respectively. At follow-up, which ranged from 9 to 24 months with a mean of 14.1 months, the mean sagittal relapse at the B point was 1.9 mm. Although heretofore considered unstable and therefore not clinically accepted, maxillomandibular counterclockwise rotation to normalize the occlusal plane rotational deformity provides stable, aesthetically superior results in patients with extreme degrees of mandibular micrognathia. Extended follow-up will be necessary to document long-term stability.

Forty-three nonconsecutive patients presenting with dentofacial deformity underwent surgical procedures designed intentionally to create skeletal disproportion in the sagittal and/or vertical dimensions. This was accomplished through expansion (enlargement) of the facial skeleton beyond normative standards. At the time of follow-up, which ranged from 14 to 36 months (mean 18.4 months), soft-tissue cephalometric analyses documented facial disproportion to exist in 37 of the 43 patients treated. Thirty-two patients had excessive anterior divergence (facial protrusion) at pogonion, and 17 patients had excessive lower face height as measured from subnasale to menton. All patients were judged to have had a favorable aesthetic outcome. This philosophy of facial skeletal expansion is predicated on two concepts: The first of these is that facial proportions and dimensions beyond those which are considered normal may be extremely attractive in a given individual. Second, the soft-tissue response to skeletal expansion is more favorable and predictable than it is to skeletal contraction in providing for well-supported soft tissues. This treatment planning approach is based on the dynamic interrelationship between the skeletal foundation and the soft-tissue facial mask. It relies on physical examination as the major determinant of aesthetic surgical options.

Two patients are presented in whom severe clinical infection developed in tissue adjacent to and contiguous with previously implanted blocks of porous hydroxyapatite. Both infections resolved with appropriate antibiotics, debridement, and drainage of infected tissues. Hydroxyapatite blocks were left in situ. This unusually favorable response of an alloplast to infection is attributable to the abundant vascular supply of this porous implant. Although reliable dogma can hardly be concluded from two clinical examples, these experiences suggest that once ingrown, porous hydroxyapatite does not behave in a fashion that is typical of foreign bodies in the midst of infection. For the first time, clinical evidence has been offered to support the experimental data that vascularized hydroxyapatite has the ability to resist infection.

The vast majority of patients requesting aesthetic enlargement of their chins have a class II skeletal deformity secondary to a small mandible. Class II skeletal patterns are frequently associated with abnormalities of lower face height, which, in turn, affect labiomental fold morphology. Of 68 patients who were to undergo sagittal advancement of their chins, 88 percent were considered to have abnormal labiomental fold morphology that was closely related to abnormalities of the facial height. Patients with decreased lower face height (40 percent) had exaggerated, deepened folds with acutely closed angles between the lower lip and chin pad, whereas those with increased lower face height (25 percent) had shallow, effaced folds. Patients with normal lower face height had variable fold morphology. Isolated sagittal advancement and/or simultaneous advancement and vertical shortening deepened the labiomental fold and closed the angle between the chin pad and lower lip. Simultaneous advancement and lengthening tended to deemphasize the fold, making it appear less deep in 20 of 34 patients, or at least mitigated further accentuation of the fold in 14 of 34 patients. Altered labiomental morphology and its relationship to the class II skeletal deformity is discussed. Treatment planning decisions are suggested, taking into account labiomental aesthetics and how they are influenced by advancement genioplasty.

Seventy-six nonconsecutive patients undergoing orthognathic surgery, in whom blocks of porous hydroxyapatite were implanted into osteotomy gaps in lieu of autogenous bone grafts, are the subjects of this report. Surgical procedures include inferior maxillary repositioning (10 patients), maxillary advancement (24 patients), transverse maxillary expansions (17 patients) and inferior repositioning of the chin (25 patients). A total of 140 anatomic sites were implanted. Eleven patients later consented to open biopsy of the implant material at a mean 10.2 months following implantation. At the time of follow-up, mean 16.3 months, excellent osseous stability was observed. Three patients developed complications relative to the presence of the implant. Twenty-one of 24 biopsy specimens demonstrated an osseous union of implant to bone with osseous deposition within the implant pores. Radiographic follow-up revealed implant blocks to maintain their volume with no change in density or discreteness. The biological behavior and biomechanical properties of porous block hydroxyapatite are discussed. These implant characteristics make it a feasible bone graft substitute in orthognathic surgery and justify its continued use in this context.

The surgical correction of mandibular prognathism has traditionally involved posterior repositioning of the mandibular body. This treatment approach corrects the skeletal disproportion at the expense of reducing facial skeletal volume and can unpredictably result in inadequately supported soft tissues with loss of skeletal definition. In an effort to avoid these sequelae of mandibular reduction, 18 patients diagnosed as having mandibular prognathism were treated with maxillary advancement surgery at the Le Fort I level. Mean patient SNB angle was 85.2 degrees, as compared with a normal 79 +/- 3 degrees. Maxillae were documented to be in normal position relative to both cranial base and Frankfort horizontal. The mean maxillary advancement was 6.9 mm, with a range of 4.5 to 8.8 mm. All patients required genioplasty to reduce vertical chin height and/or to laterally shift the chin. At the time of follow-up (mean 16.2 months), all patients retained cephalometric data suggestive of enlarged mandibles and excessive anterior facial divergence. However, maxillomandibular harmony and facial convexity had been restored without sacrificing skeletal volume. Treatment results demonstrated these faces to be skeletally well proportioned despite lower face protrusion that was beyond "normal." Postoperative appearances were characterized by a well-supported soft-tissue envelope and a highlighted skeletal foundation, creating angular, well-defined lower faces. These findings support the credibility of maxillary advancement as the procedure of choice in selected individuals with mandibular prognathism. Indications and an aesthetic rationale for this surgical approach are presented.

Osteotomy at various levels of the facial skeleton is entirely justified in selected aesthetic surgical patients. By the very nature of aesthetic surgery, the morbidity potential associated with such osteotomies must be extremely low. Accordingly, osteotomy at the symphyseal level and the LeFort I level are the most commonly performed procedures in the aesthetic surgical patient. Aesthetic changes required in the vertical plane of space will require osteotomy, because these cannot be reliably and consistently achieved through changes in skeletal surface contour. Lastly, when the extent of change required is greater than what can be naturally achieved with surface augmentation, osteotomy must be considered. This last indication is frequently found in the aesthetic surgical patient presenting with a facial skeletal imbalance that has been previously treated with orthodontics to correct a skeletally based malocclusion. Recent technical advances have markedly reduced the associated morbidity of facial osteotomies and, therefore, have made this treatment option more acceptable to aesthetic surgical patients. Ceramic orthodontic brackets and surgical hooks and lingual orthodontic appliances have made presurgical orthodontic preparation more aesthetic and socially acceptable for LeFort I osteotomy patients. The use of rigid fixation, obviating the need for any postoperative intermaxillary fixation, has also made this treatment approach more appealing to aesthetic patients. Lastly, the efficacy of nonresorbable bone substitutes--in particular, porous, block hydroxyapatite--has, to a significant extent, obviated the need for harvesting autogenous bone grafts, further reducing surgical morbidity.

A case is presented of lactation occurring ten days after mastopexy with augmentation mammaplasty. Milk-draining sinuses involving the operative incisions necessitated prompt diagnosis and treatment to avoid breast implant loss. Bromocriptine, an ergot derivative, was used to suppress a pathologically elevated prolactin level and successfully effect a rapid resolution of lactation.

Eleven patients who previously had undergone elective facial osteotomy and in whom blocks of porous hydroxyapatite were implanted into osteotomy gaps later consented to open biopsy of the implant material. A total of 24 biopsies were harvested at a mean time of 10.2 months following implantation. Gross anatomic findings were recorded at the time of biopsy. Specimens were harvested from the zygomatic buttress of the maxilla (12), the piriform buttress of the maxilla (4), the maxillary interdental premolar region (2), and the anterior mandible (6). Histologic sections were examined undecalcified using a modified trichrome stain. Eight of the 11 patients were followed radiographically for a minimum of 24 months. In the absence of infection, there was rapid fibrovascular ingrowth and, provided there was contact with host bone, bone ingrowth. This was observed in 21 of 24 biopsy specimens. The extent of bone ingrowth, as judged qualitatively, was highly variable and did not correlate with the time interval from implantation, anatomic site, or surface area of bone-implant interface. A healing process involving an osteoid phase of bone maturation and suggestive of continued net bone production was consistently found. The gross anatomic, radiographic, and histologic findings are discussed and provide further insight into the biologic behavior of porous block hydroxyapatite implanted into the maxillofacial skeleton.

Inferior repositioning of the maxilla to correct vertical maxillary deficiency has been associated with variable degrees of instability and subsequent relapse. Resorption of bone-graft material has been incriminated as the primary cause of postoperative instability. This paper reports on nine patients who have undergone inferior maxillary repositioning resulting in no residual bone contact between the down-fractured maxilla and superior midface. Mean inferior maxillary repositioning was 6.2 mm. Osteotomy gaps were implanted with porous block hydroxyapatite (Interpore 200), and maxillae were rigidly fixed in position with miniplates. No postoperative intermaxillary fixation was utilized in any patient. Follow-up ranged from 11 to 28 months, with a mean of 19.6 months. Cephalometric analyses at follow-up revealed excellent stability of the repositioned maxillae, with a mean vertical relapse of 4.3 percent. No complications were associated with this procedure. The biomechanical rationale contributing to the success of this operative technique is discussed.

Forty-one patients undergoing Le Fort I osteotomy for superior and/or anterior repositioning of the maxilla were prospectively studied for changes in soft-tissue morphology of the nasomaxillary region. Nasal parameters studied were changes in interalar rim width and nasal tip projection. It was observed that alar rim width increases with anterior and/or superior repositioning of the maxilla, but increases in nasal tip projection occur only when there is an anterior vector of maxillary movement. These nasal changes could not be quantitatively correlated to magnitude of maxillary movement. Lip changes studied were the horizontal displacement at the vermilion border and subnasale versus that of the incisal edge and point A, respectively, when the maxilla is sagittally advanced and the vertical shortening of the lip versus that of the incisal edge when the maxilla is shortened. Using linear regression analysis, horizontal displacement of the upper lip at the vermilion border was 0.82 +/- 0.13 mm for every 1 mm of maxillary advancement at the incisal edge (p less than 0.001) and 0.51 +/- 0.13 at the subnasale for every 1 mm of maxillary advancement at point A (p less than 0.001). Eighty percent of patients undergoing maxillary intrusive procedures had lip shortening ranging from 20 to 50 percent of the vertical maxillary reduction. Surprisingly, no statistically significant correlation could be demonstrated for lip shortening versus extent of vertical maxillary reduction. Previous literature in disagreement with these findings is discussed. Guidelines for treatment planning utilizing these data are suggested.

Surgical correction of the vertically deficient chin has received relatively little attention. This paucity of information is most likely related to the failure to diagnose vertical microgenia and the questionable stability of its surgical correction utilizing autogenous bone grafts. This paper reports on eight patients who have undergone vertical augmentation genioplasty utilizing a transverse symphyseal osteotomy and interpositional implantation of porous, block hydroxyapatite. All patients had preoperative measured decreases in lower face height. Mean vertical lengthening of the chin was 5.3 mm. Seven of the eight patients had class II occlusions and underwent simultaneous sagittal advancement of the chin. Follow-up at a mean time of 11.1 months revealed complete stability of the vertically repositioned symphyseal segment. Mean ratio of the vertical soft to hard tissue augmentation was 0.89:1. There were no instances of operative complications. Vertical facial aesthetics and their application in the evaluation and treatment of patients with vertically deficient lower faces and chins are reviewed.

Preischemic perfusion washout with an acellular physiologic solution delays the no-reflow phenomenon and improves tissue survival in rat epigastric free flaps following 18 and 24 hours of normothermic ischemia. This implies that stagnating blood may be a causative agent in the no-reflow phenomenon. A possible mechanism for this is capillary endothelial damage secondary to the presence of formed blood cells or their products of hemolysis. Perfusion washout may improve ischemic tolerance by preventing this blood cell-induced endothelial damage and by the prevention of sludge and thrombus. Whether any of the metabolic components of the perfusate actively enhance ischemic tolerance cannot be definitively stated.

Congenital craniofacial asymmetry has two dominant causes: isolated synostosis and craniofacial clefts. Treatment considerations in these problems differ from those with isolated cranial or isolated facial defects. Isolated cranial defects are most frequently treated by the neurosurgeon with craniectomy alone. Isolated facial asymmetry when congenital in origin usually manifests as hemifacial microsomia and based on our experience with 40 such patients, is best treated in later childhood. Treatment timing of craniofacial asymmetry varies with the cause, but is best done in the first two years of life. Nasofrontal encephaloceles are usually best treated in the first few weeks of life; synostosis syndromes are treated at six months of age after the facial sutures have had time to stabilize sufficiently for adequate dissection and mobilization; and other craniofacial clefts at approximately two years of age following descent of the teeth and better homeostatic capability of the patient. Based on our series of 58 patients, 40 treated with isolated synostosis at less than one year of age, eight at more than one year of age, and ten patients with craniofacial clefts, the guidelines for timing and methods of treatment have evolved. Liberal use of craniectomy bone with expected regrowth is possible in the first year of life, and more limited use in the second year of life. This bone is used to hold the repositioned orbit, augment hypoplastic zygomas, and reconstruct noses, or for other uses. In isolated synostosis, repositioning provides a form of immediate catch-up growth then proceeds normally. In craniofacial clefts, repositioning puts structures into normal relations and growth likewise proceeds normally. The isolated synostosis syndromes treated at a later age are done with more difficulty, though may be effectively cared for. Complications other than incomplete structural correction have been nonexistent in the group two years of age and less.

The Health Care Financing Administration recently released a list of hospitals with allegedly excessive mortality rates. This paper examines and explains several flaws in the mortality study that are important to consider for proper interpretation and understanding of the HCFA results.

The principles and techniques of the surgical management of malignant cranio-orbital tumors are discussed in this article. Emphasis is placed on soft-tissue reconstructive requirements of the cranial base. Only in this way can operative morbidity and mortality be minimized.

Forty-six nonconsecutive patients undergoing orthognathic surgery in whom blocks of coralline, porous hydroxyapatite (Interpore-200) were used in lieu of interpositional bone grafts are the subjects of this report. Surgical procedures included inferior repositioning of the maxilla (7) and chin (12), maxillary advancements in cleft (4) and noncleft individuals (13), and transverse maxillary expansions (12). Patients included in this study were only those in whom bone grafts would have been harvested had hydroxyapatite not been available. A total of 93 anatomic sites were implanted. The complication rate attributable to the use of the implant was 4.3 percent. Follow-up period ranged from 6 to 20 months, with a mean of 9.3 months. At this time, osseous stability was confirmed cephalometrically in all but two patients undergoing maxillary expansions. The biologic behavior and mechanical properties of coralline-derived, porous, block hydroxyapatite are discussed. These implant characteristics make it a feasible bone graft substitute for interpositional use in orthognathic surgery. Proper indications for its use as well as technical details to minimize complications are stressed.

A seminar in quality of care analysis was developed with three objectives in mind: (a) to familiarize health administration students with methods for measuring the quality of health care (b), to sensitize students to complexities of the medical care process, and (c) to provide a setting where students interact directly with physicians in dealing with a common problem. Students developed individual evaluation projects at participating institutions in cooperation with faculty of the program and staff at the institutions. Evaluation of the seminar in terms of state objectives was performed both quantitatively and qualitatively. Indications are that the course was well accepted by students and achieved its major goals.

Amputated rat hindlimbs were subjected to either normothermic (26 degrees C) or hypothermic (4 degrees C) ischemia. Experimental limbs had their microcirculation washed out (either before or after the ischemic insult) with a physiologic acellular plasma substitute previously reported to enhance flap survival following extended periods of warm ischemia. Control limbs were not washed out; i.e., stagnant blood remained in these limbs. Following the ischemic interval, amputated limbs were replanted. Monastral blue B, a colloidal pigment capable of labeling leaky blood vessels, was administered systemically to all rats just prior to vascular declamping. Limb biopsies of skin and muscle were harvested 30 minutes following revascularization in order to assess Monastral labeling and, therefore, the functional integrity of the microcirculation. Results confirm that stagnant blood under conditions of warm ischemia is detrimental to the functionality of the microcirculation in both skin (p less than 0.03) and muscle (p less than 0.007). Accordingly, perfusion washout, when performed prior to the ischemic period, enhances limb survival following 6 hours of warm ischemia (p less than 0.01). Hypothermia protects against the detrimental effects of stagnant blood; perfusion offers no benefit if hypothermic conditions prevail. Physiologic mechanisms responsible for these findings are discussed.

Operative morbidity, including osteomyelitis and meningeal and cerebral sepsis, remains high among patients undergoing the composite (bony and overlying soft tissue) resection of malignant skull base tumors. This is in part because of the poor wound healing afforded by free skin grafts and the poorly vascularized pericranial flaps routinely used to resurface the operative defect. In an effort to reduce the operative morbidity, single stage resection and reconstruction with distant vascularized flap tissue was performed in five consecutive patients who presented with malignant skull base tumors. We think that immediate flap reconstruction will allow skull base lesions previously considered unresectable or associated with a prohibitive complication rate to be safely resected. Case presentations illustrate operative techniques. The potential disadvantage of masking a tumor recurrence with immediate flap coverage is discussed.

We asked whether surgical process and outcome differ for physicians in postgraduate training supervised by attending surgeons compared with attending surgeons alone. All appendectomies performed during a 2 year period in a 320 bed voluntary hospital where either the admitting diagnosis or the preoperative diagnosis suggested acute appendicitis were included in the study. Data were abstracted from medical records and pathology reports. One hundred fifty-four cases of primary appendectomy were reviewed. In 97 cases, 1 of 9 attending physicians was listed as chief surgeon; in 57 cases, 1 of 15 resident physicians was listed as chief surgeon. There were no significant differences between the two patient groups according to age and sex. There was no difference between attending resident physicians in accuracy of diagnosis. Despite a pathologically normal appendix, attending surgeons in six cases and residents in two cases listed a discharge diagnosis of appendicitis. The average length of stay was 8.8 days for attending surgeons' cases and 7.1 days for residents' cases (t = 1.09, p = 0.29). The postoperative complication rates were 24 percent for attendings' cases and 12 percent for residents' cases (chi-square = 2.31, p = 0.16). We conclude that there is no appreciable difference in either the process or the outcome of care for patients undergoing appendectomy whether the operation is performed by an attending physician or a resident physician supervised by an attending physician.

A case of osteomyelitis of the forefoot is presented. The defect was unusual in that both medial and lateral wounds were larger than the osseous tunnel that connected them. A double skin island latissimus dorsi vascularized flap utilizing larger skin islands than the diameter of the muscle pedicle perfusing them allowed for wound closure. The high density of musculocutaneous perforating vessels of this muscle-skin unit permit such a technique to be safe and effective.

Capitation reimbursement has been an integral part of prepaid group practices in both medicine and dentistry, and claims have been made for its ability to influence the delivery of services favorably. Experts have suggested that if capitation is implemented, more preventive care will be provided, more diagnostic services will be provided, there will be better continuity of care, utilization of high-cost services will be reduced, and clinical outcome will be improved. This study focused on the dominant mode of practice in dentistry, the general, solo practitioner, to determine if these contentions held. A sample of 245 patients whose care was paid for by a capitation mechanism was matched to a sample of 245 similar patients whose care was paid for on a standard fee-for-service basis--all from three dentists' practices. All services in all years of care for each patient were analyzed. It was determined that the rate of restorations was lower, while rates of diagnostic testing and prophylaxis were higher for capitation patients. Continuity was also better under capitation, but rates of extractions were virtually identical for the two groups.

Recent experimental data have demonstrated improved flap survival following perfusion washout with a synthetic, chemically defined, mammalian plasma. In an effort to define the physiology responsible for the efficacy of perfusion, the method of "labeling" hyperpermeable blood vessels with Monastral blue B in rat epigastric vascular island flaps was utilized. Results confirmed that capillary and venular hyperpermeability is an early and progressive pathophysiologic event in ischemic flap tissue and one which is reversible prior to a critical ischemic period. Perfusion washout with a physiologic, acellular plasma substitute delays the onset of vascular hyperpermeability. This may be a mechanism responsible for improving tissue survival following extended periods of warm ischemia (12 hours). It is implied that stagnant blood and products of hemolysis in the microcirculation may be detrimental to the functional and anatomic integrity of the endothelial wall.

Previous work from this laboratory has suggested that the plasma amino acid pattern, known to be deranged in hepatic encephalopathy, may be related causally. In order to test this hypothesis, 23% dextrose and a special amino acid solution whose components were calculated to normalize the plasma amino acid pattern were infused in 11 patients, eight with chronic cirrhosis and acute exacerbation (Group 1) and three patients with fulminant hepatitis (Group 2), in amounts of up to 120 Gm. of protein equivalent per 24 hours. Plasma amino acids were abnormal but different in both groups. In Group 1 (cirrhosis) changes in plasma amino acid pattern including elevated phenylalanine, tyrosine, glutamate, aspartate, and methionine and decreased valine, leucine, and isoleucine. In Group 2 all amino acids were elevated, with the exception of the branched chains which were normal. Hepatic encephalopathy improved in all patients in Group 1 and in one of three patients in Group 2 following the infusion. The ratio (see article) showed an excellent correlation with a grade of encephalopathy. When this ratio, previously 1.0 in the presence of encephalopathy, returned to the normal value near 3.0 to 3.5, encephalopathy improved. An excellent correlation was obtained between the ratio and the grade of encephalopathy and was dose related as well. The results suggest that different amino acid patterns in hepatic encephalopathy of differing etiologies require treatment modalities which may differ for the two types of encephalopathy. Whereas amino acid infusion appears to be a valuable, efficacious way of providing nutrition in treating hepatic encephalopathy in patients with cirrhosis and acute deterioration and coma, other means of therapy such as plasms "laundering" appear to be necessary in patients with fulminant hepatitis.

Multiple segment Le Fort I osteotomies provide the maxillofacial surgeon with the capabilities to treat complex dentofacial deformities existing in all three planes of space. Sagittal, vertical, and transverse maxillomandibular discrepancies as well as three-dimensional abnormalities within the maxillary arch can be corrected simultaneously. Accordingly, optimal aesthetic enhancement of the facial skeleton and a functional, healthy occlusion can be realized. What may be perceived as elaborate treatment plans are in reality conservative in terms of osseous stability and treatment time required. The close cooperation of an orthodontist well-versed in segmental orthodontics and orthognathic surgery is critical to the success of such surgery. With close attention to surgical detail, the complication rate inherent in such surgery can be minimized and the treatment goals achieved in a timely and predictable fashion.

The use of the extended posterior trapezius muscle skin flap for cranio-orbital facial reconstruction is presented. Its enormous arc of rotation allows it to reliably reconstruct massive defects of the upper face with the orbit at the center of the defect; i.e., this flap will reach well beyond the supraorbital rim and across the midline. Its application for the immediate reconstruction of massive deformities following resection of tumors of the orbit and cranial base appears justified and helps avoid the major morbidity normally associated with such resections.

Plasma amino acids were measured in 18 patients with hepatic encephalopathy on a protein-restricted diet of 20 g or less daily. Plasma aminograms tended to group into two distinct patterns depending on the etiology of the patients' hepatic pathology. Patients with chronic liver disease with superimposed acute insults, i.e., gastrointestinal bleeding, infection, alcoholic hepatitis, had elevated levels of the aromatic amino acids, phenylalanine, tyrosine, and tryptophan, as well as methionine, glutamate, and aspartate, whereas levels of the branched chain amino acids, valine, leucine, and isoleucine, were consistently depressed. Those patients with previously normal livers and acute hepatic necrosis, i.e., "fulminant hepatitis," had grossly elevated levels of all amino acids except the branched chain amino acids, which were normal. Elevations of amino acid levels in this patient group tended to correlate with extent of hepatic necrosis and hence had prognostic significance. Additionally, the different patterns seen in these two groups tend to suggest the indicated therapy as well as predict its efficacy.

Two matched samples of 245 patients were drawn from solo dental practices which contained both capitation and fee-for-service components. All services rendered to patients during their entire time under care of the practice were recorded and analyzed. Results indicate different styles of care under the two payment mechanisms. An improved preventive style was associated with capitation, as well as fewer fillings. Outcome measured by a modification of the DMF (decayed-missing-filled) Index was also more favorable under capitation.

In an effort to determine the sum of the factors influencing the plasma and brain concentrations of aromatic amino acids in rats with liver disease, rats with end-to-side portacaval shunts and their sham-operated controls were placed on various oral and intravenous diets by the techniques of parenteral nutrition. In sham-operated animals with normal hepatic function, the source of amino acids and their composition appeared to play little role in the plasma and brain aromatic amino acids and a derivative of brain tyrosine, octopamine. After end-to-side portacaval shunt, however, plasma and brain concentrations of aromatic amino acids were responsive to exogenous intake in the presence of hepatic impairment. In a group of rats with end-to-side portacaval shunt and presumed hepatic impairment, graded increments of protein equivalent were given with isocaloric hypertonic dextrose by the techniques of parenteral nutrition. When the animals achieved positive nitrogen balance, there were decreased levels in plasma and brain of the aromatic amino acids, phenylalanine and tyrosine, and a derivative of tyrosine, octopamine. A clear statistical relationship between plasma and brain tryptophan and nitrogen balance was not observed. The results suggest that in animals with hepatic impairment secondary to end-to-side portacaval shunt both exogenous intake and the level of catabolism (nitrogen balance) influence plasma and brain aromatic amino acids.

Cephalometric analyses of twenty-one patients with Crouzon's disease were undertaken to correlate the cranial base abnormalities to altered facial morphology. Angular deformities of the cranial base, i.e., the vertical sloping of the anterior cranial fossa and the angulation of the cranial base flexure were found to correlate well to observed exorbitism and midface retrusion , respectively. Normal craniofacial growth and clinical implications of these data are discussed.

We present a case report of symptomatic, spontaneous subdural hygromas complicating craniofacial resection of a malignant skull base tumor. This complication occurs after prolonged spinal drainage instituted to prevent cerebrospinal fluid fistulas secondary to insecure dural repair. We believe that this complication may be seen repeatedly as indications for craniofacial surgery in the elderly continue to expand.

The use of rigid, internal, three-dimensional fixation using vitallium bone plates in 28 consecutive Le Fort I osteotomies is presented. A minimum follow-up period of 6 months was required for inclusion in this patient group. Maxillary movements included advancements (17), intrusions (9), lengthenings (5), and retrusions (2). The majority of maxillae were moved in more than one plane of space. Technical details, complications, and relapse potential are discussed. Advantages of rigid plate fixation include marked reductions in the length of intermaxillary fixation with light training elastics only. Immediate postoperative airway problems are thereby eliminated. Six months of follow-up would appear to indicate a low potential for osseous relapse when compared to wire osteosynthesis, regardless of the direction of maxillary movement. The major disadvantage is the decreased ability of postoperative orthodontics to move dento-osseous segments if skeletal occlusal disharmony persists postoperatively. For this reason, close attention to preoperative planning and operative technique is critical for the success of this fixation method.