Biomedical subjects

L B Kaban

Publications and source records attributed to L B Kaban.

At least 91 records · Page 5Linked to original sources

PubMed1990

The role of a temporalis fascia and muscle flap in temporomandibular joint surgery.

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.

Cartilage, Articular↗

PubMed1990

A prospective evaluation of the effectiveness of temporomandibular joint arthroscopy.

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.

Adult↗

PubMed1990

Tissue response to composite ceramic hydroxyapatite/demineralized bone implants.

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.

Alveolar Process↗

PubMed1990

Fixation of mandibular fractures: a comparative analysis of rigid internal fixation and standard fixation techniques.

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.

Adult↗

PubMed1990

A protocol for management of temporomandibular joint ankylosis.

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.

Adolescent↗

PubMed1990

Effect of demineralized bone powder on osteoblast-like cells in culture. A potential rapid quality control assay.

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.

Alkaline Phosphatase↗

PubMed1989

Pediatric maxillofacial infections: a retrospective study of 113 patients.

This is a retrospective review of 113 hospitalized children with maxillofacial infections. The upper face (orbits, paranasal sinuses, maxillary teeth, and cheeks) was affected most frequently in younger children (mean age = 4.03 years), and the source of infection was often unknown. The patients were treated empirically with a second-generation cephalosporin. Lower-face infections (mandibular teeth, submental, sublingual, and submandibular structures) occurred more frequently in older children (mean age = 5.56 years) and were likely to be of odontogenic origin. Empiric therapy in lower face infections usually consisted of penicillin.

Adolescent↗

PubMed1989

Effect of Le Fort III osteotomy on mandibular growth in patients with Crouzon and Apert syndromes.

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.

Acrocephalosyndactylia↗

PubMed1989

Central giant cell granulomas of the jaws. Nuclear DNA analysis using image cytometry.

Giant cell nuclear DNA, in 30 giant cell lesions of the jaws, was quantified by computer-assisted image analysis. DNA content was then used to predict clinical behavior and outcome. 4 nuclei in each of 25 giant cells (total = 100 nuclei) were randomly selected and the DNA content was quantified by the Leitz Texture-Analysis-System-Plus. DNA in nuclei of normal appearing stromal fibroblasts (n = 20) was similarly measured. The DNA index was calculated as the mean nuclear DNA content of giant cells divided by the mean DNA content of control fibroblasts. The mean DNA-index of aggressive lesions (1.09, SD = 0.12) was not significantly different from that of non-aggressive lesions (1.18, SD = 0.15) (p = 0.093). The results indicate that the nuclear DNA content of giant cells is not useful as a predictor of the clinical behavior of giant cell lesions of the jaws.

Adolescent↗

PubMed1989

Temporomandibular joint: morphology and signal intensity characteristics of the disk at MR imaging.

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.

Adult↗

PubMed1988

California mandatory seat belt law: the effect of recent legislation on motor vehicle accident related maxillofacial injuries.

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).

Accidents, Traffic↗

PubMed1988

Smooth-muscle tumors of the oral cavity.

Smooth muscle tumors of the oral cavity are rare. The world literature revealed 80 leiomyomas and 21 leiomyosarcomas. We presented one new case of each lesion in this report and discussed diagnostic and treatment considerations and prognosis. Treatment recommendations for leiomyoma and leiomyosarcoma require an en bloc excision with at least 1-cm margins of normal tissue. Both lesions may look alike clinically and may not even be definitively differentiated histologically; therefore, a follow-up period of 5 years is suggested.

Child↗

PubMed1988

Surgical correction of hemifacial microsomia in the growing child.

This is a follow-up study of 20 children who had surgical correction of hemifacial microsomia in an effort to improve facial growth and minimize secondary distortion. In group 1 (skeletal types I and IIA), 10 children underwent elongation and lengthening of the mandible. In group 2 (skeletal types IIB and III), 10 children had total construction of a new temporomandibular joint and mandibular ramus with rib grafts and costochondral junction. In both groups, an open bite was created on the affected side to provide space for tooth eruption and downward growth of the middle face. The mean follow-up was 50.9 months (18 to 117 months) in group 1 and 45 months (18 to 50 months) in group 2. Analysis of our early results showed that all patients have had downward growth of the midface on the affected side. All five patients in group 1, followed to complete closure of the surgically created open bite, have maintained a level occlusal plane. In group 2, the one patient followed to completion of facial growth continues to have a level occlusal plane and facial symmetry. Appropriately timed mandibular construction and/or elongation in children with hemifacial microsomia is safe and effective. There is a decrease in secondary deformity on the affected side, and the eventual overall facial growth is optimized. Some group 2 children will need secondary elongation and augmentation of the mandible. Nevertheless, this study demonstrates that early mandibular correction may obviate the need for maxillary and orbital procedures in adulthood.

Bone Transplantation↗

PubMed1987

Central giant cell lesions of the mandible and maxilla: a clinicopathologic and cytometric study.

Computer-assisted image analysis was used to measure four histopathologic parameters (number of giant cells, mean number of nuclei per giant cell, fractional surface area, and relative size index) in two groups of patients with central giant cell lesions in a search for possible histologic predictors of clinical behavior. The lesions of 22 patients were classified clinically into nonaggressive and the lesions of 10 patients were classified into aggressive categories in accordance with the method of Chuong and Kaban. The majority of patients with aggressive lesions had recurrent tumors within 2 years and/or experienced pain, root resorption, and cortical perforation. Giant cells were selected in 25 random high-power magnification (X400) fields and measured by means of the Leitz Texture Analysis System-Plus. Linear stepwise discriminant analysis was applied to each parameter studied. Clinically aggressive giant cell lesions were characterized by a higher number of giant cells and greater fractional surface area when compared with the nonaggressive tumors. With the use of the "jackknife" classification procedure, the accuracy of the two statistically significant parameters (number of giant cells and fractional surface area) in predicting the aggressiveness or the nonaggressiveness of our group of central giant cell granulomas was, respectively, 70% and 82%. This study provides further evidence that the use of cytometric analysis of giant cells may be helpful in predicting prognosis and in planning treatment for these often difficult-to-manage lesions.

Adolescent↗

PubMed1987

Fragmented care of facial fractures.

The treatment of facial trauma currently falls within the purview of several surgical subspecialties, including plastic surgery, oral and maxillofacial surgery, otolaryngology, ophthalmology, and neurosurgery. The complexity of facial anatomy and the newer techniques for skeletal and soft-tissue reconstruction demand interdisciplinary, rather than multidisciplinary, care for these injuries. Interdisciplinary cooperation benefits the patient with a complex facial fracture by: minimizing chances for inadequate primary therapy, promoting discussion of controversial therapy, and providing the optimal therapy. Examples are given of unfavorable results following treatment of facial fractures. Recommendations are made to foster communication between the concerned surgical subspecialties.

Adolescent↗

PubMed1987

Temporomandibular joint dysfunction and facial pain in children: an approach to diagnosis and treatment.

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.

Adolescent↗

PubMed1987

Analysis and treatment of hemifacial microsomia in childhood.

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.

Adolescent↗

PubMed1986

Central giant cell lesions of the jaws: a clinicopathologic study.

The biologic behavior of central giant cell lesions of the jaws ranges from quiescent to aggressive with destructive expansion. To date, these variations have not been explained by the findings of routine histologic examination. This retrospective clinicopathologic study of giant cell lesions was performed to search for histologic correlates of biologic behavior. Lesions in 17 patients were classified clinically as nonaggressive (group I) or aggressive (group II). In general, group II lesions affected children at an earlier age, were larger at the time of diagnosis, and recurred more frequently. The following histologic parameters were assessed: fractional surface area occupied by giant cells (FSA), relative size index of giant cells (RSI), stromal characteristics, mitotic index, inflammatory cells, and hemosiderin content. Histologic differences between the two groups were not as clear as the differences in biologic behavior. However, aggressive lesions had a higher RSI, and recurrent giant cells lesions had a higher RSI and FSA; these parameters warrant further study. In addition, electron microscopic differences in a small number of aggressive and nonaggressive lesions were documented.

Adolescent↗