The role of muscle grafts in temporomandibular joint ankylosis: short-term experimental study in sheep.

The temporalis muscle flap can be used as an inter-positional graft placed into a gap arthroplasty site in temporomandibular joint (TMJ) ankylosis. The purpose of this study was to investigate the role of the muscle graft in sheep. Five pure-bred adult Merino sheep were used and ankylosis was induced in all right TMJs. At 3 months, the ankylosis was released by gap arthroplasty and reconstructed with a masseter muscle graft, because the temporalis muscle is short and poorly vasculized in sheep. The sheep were killed at 3 months after muscle grafting. The maximal mouth opening was recorded before and after operation and at death. The joints were examined radiologically and histologically. In 4 sheep mouth opening remained at the pre-operative level. A clear radiolucent space remained between the smooth temporal and ramus stumps. Histologically, the muscle graft remained vital but with some fibrous tissue formation between the bone ends. One sheep developed an infection at the operative site following the muscle graft; this partly resolved with antibiotics, but the TMJ developed a fibrous reankylosis that was demonstrated clinically, radiologically and histologically. These results indicate that an uncomplicated temporalis muscle graft reconstruction with gap arthroplasty is a successful and stable procedure in human TMJ ankylosis.

Pleomorphic adenoma of the salivary glands: correlation between gallium-67 uptake and histopathological components.

UNLABELLED: We correlated 67Ga uptake and histopathological findings in pleomorphic adenomas of the salivary glands. METHODS: Sixty-two pleomorphic adenomas of the salivary glands were visually graded by degree of 67Ga uptake as negative, weakly positive or strongly positive in comparison to uptake in the nasal cavity. These adenomas were re-examined pathologically and classified as epithelial, intermediate or mesenchymal type according to their dominant histological components. The pathological presence of marginal invasion or associated sialoadenitis was also re-examined. RESULTS: Eighteen adenomas were classified as strongly positive, eight as weakly positive and 36 as negative. Nine (50%) of the 18 strongly positive adenomas were of the epithelial type and the other nine (50%) strongly positive adenomas were of the intermediate type. While none of the strongly positive adenomas were of the mesenchymal type, 27 (75%) of the 36 negative adenomas were of the mesenchymal type. Six (75%) of the eight weakly positive adenomas were of the intermediate type. About half of the adenomas showed marginal invasion regardless of the grade of 67Ga uptake. None of the strongly positive adenomas were associated with sialoadenitis. CONCLUSION: The epithelial component of pleomorphic adenomas may be responsible for 67Ga uptake. The presence of marginal invasion or associated sialoadenitis has little relation to 67Ga uptake in pleomorphic adenomas.

Analysis of genetic alterations in salivary gland tumors by comparative genomic hybridization.

In order to define and map chromosomal copy number alterations in salivary gland tumors (SGTs), a comparative genomic hybridization (CGH) technique was applied to two pleomorphic adenomas (PAs), one adenoid cystic carcinoma (ACC), and one basal cell adenocarcinoma (BCAC). The PAs exhibited regional copy number losses at 5q12.4-q14.1, 9q12-q21.13, and 16q11.2, as well as a gain at 20p12.1; among these, the losses at the 9q12-q21.11 and 16q11.2 regions were common to both PAs. The ACC showed overrepresentations of the entire regions of chromosomes 16 and 20, a regional gain at 22q12.3-q13.1, and no losses. In the BCAC, regional gains at 9p21.1-pter, 18q21.1-q22.3, and 22q11.23-q13.31 as well as losses at 2q24.2 and 4q25-q27 were seen; the gain at 22q12.3-q13.1 was common in both the ACC and the BCAC. These CGH data indicate that different genetic alterations are present in the different types of SGTs, and that the alterations involve several chromosomes. The discovery of common alterations in the same and/or different types of tumors might be important in the understanding of the development and progression of the SGTs.

The limitations of gallium scintigraphy in the differentiation between benign and malignant salivary gland mass lesions.

The aim of this study was to evaluate the ability of gallium scintigraphy to differentiate between benign and malignant salivary gland mass lesions and to identify what types of lesions surpass its diagnostic utility. By considering the uptake of 67Ga, 193 salivary gland masses were graded visually as negative, weakly positive, moderately positive or strongly positive in comparison to the uptake in the nasal cavity and the liver. The uptake was compared with histopathological findings. Among 39 malignant tumours, uptake was positive in 31 (79%) (strongly positive in 18, moderately positive in seven and weakly positive in six) and uptake was negative in eight (21%). Adenoid cystic carcinoma was the most common malignant tumour in our study (11/39), and uptake was negative in five (45%) of these tumours. Malignant tumours did not differ significantly in size despite differences in uptake. Among 154 benign lesions, uptake was negative in 101 (66%) and positive in 53 (34%) (strongly positive in 12, moderately positive in 19 and weakly positive in 22). Out of 88 pleomorphic adenomas, 41 (47%) showed positive uptake. Sensitivity, specificity and accuracy for gallium study were 80%, 66% and 68%, respectively, when the malignancy criterion was weakly positive uptake. Accuracy was greatest (83%) when the criterion was strongly positive uptake, but this criterion failed to detect more than a half of malignant tumours (46% sensitivity). In conclusion, gallium scintigraphy had limitations in differentiating between benign and malignant salivary gland mass lesions. Adenoid cystic carcinomas and pleomorphic adenomas were the principal sources of false negative and false positive results, respectively.

The effect of occlusal loss on normal and pathological temporomandibular joints: an animal study.

The effect of unilateral posterior malocclusion on temporomandibular joint intra-articular pathology was studied in sheep. In Group I, osteoarthritic changes were induced in the left temporomandibular joint by gentle scraping of the articular surface (Ishimaru and Goss, 1992). Group II had the same procedures as Group I, with concurrent extraction of all the left maxillary posterior teeth. Group III had a different osteoarthritic precondition in the left temporomandibular joint, allowing synovial fluid to contact the condylar marrow (Ishimaru et al., 1992). Group IV had the same procedure as Group III, with concurrent extraction of all the left maxillary posterior teeth. Group V had unilateral maxillary molar teeth extraction in the left side. At 3 months, the animals were sacrificed and the joints examined histologically. There were no significant differences between normal control joints and those with unilateral tooth extraction (Group V). Similarly the degree of osteoarthritic change was the same between Groups I and II. Significant differences (p < 0.05) were seen between Groups III and IV with tooth extraction increasing the osteoarthritic effects. Hence it was concluded that in sheep, malocclusion had no effect on the normal temporomandibular joint and on one type of experimental osteoarthritis, but accelerated osteoarthritic change in another model.

Kabuki make-up syndrome (Niikawa-Kuroki syndrome) with cleft lip and palate.

Kabuki make-up syndrome (Niikawa-Kuroki syndrome), recognized in Japan in 1981, is characterized by mental and growth retardation with specific craniofacial malformation such as lower palpebral eversion and depressed nasal tip. In this paper we describe a case associated with cleft lip and palate. Attention should be paid by maxillofacial surgeons to this syndrome, since 41% of the cases have been associated with cleft lip and palate (Niikawa et al., 1988; Tonoki and Niikawa, 1988).

A simple cryosurgical method for treatment of oral mucous cysts.

A simple and easy cryosurgical method to treat intraoral mucous cysts is described. Twelve female and six male patients, with mucous cysts on the lower lip and the tip of the tongue, were treated by direct application of liquid nitrogen with a cotton swab. Each lesion was exposed to four or five cycles composed of freezings of 10-30 s and thawings of double the freezing times. No anesthesia was required. All lesions had disappeared completely 2-4 weeks after one or two treatment courses of cryosurgery. In all cases, neither scarring nor recurrence was noted during the 6 months to 5 years of follow-up.

Effect of experimental disc perforation in sheep temporomandibular joints.

The effect of surgical perforation of the disc on intra-articular morphology was examined using sheep. Eight sheep had bilateral perforations and 2 animals were used as controls. After 8 months the sheep were killed and the joints examined radiologically and histologically. Osteophytes were seen on all the condylar radiographs. Histologically, there were proliferative changes in both the condylar and temporal surfaces adjacent to the disc perforations.

Effect of marrow perforation on the sheep temporomandibular joint.

The effect of surgically perforating the mandibular condyle to allow synovial fluid to contact the marrow was examined in 5 sheep temporomandibular joints. The surgical defect showed replacement of the marrow with fibro-osseous tissue and subcortical cysts. A vertical, central osteophyte emerged from the perforation, causing attenuation or perforation of the disc and temporal surface proliferation. These changes were radiographically and histologically similar to advanced osteoarthritis. This supports the concept that intraarticular micro or macrofracture may result in osteoarthritis.

The effect of an intra-articular bone fragment in the genesis of temporomandibular joint ankylosis.

The aim of this study was to examine the effect of an intra-articular bone fragment on the genesis of temporomandibular joint (TMJ) ankylosis. Twenty-two adult sheep had a unilateral operation of removal of the temporal and condylar articular surfaces, plus discectomy with or without insertion of an intra-articular bone fragment. Functionally, radiologically, macroscopically and histologically, in the group with the intra-articular bone fragment, the joints showed more advanced ankylosis both at one and three months after the operation, as compared to the group with no intra-articular bone. This study shows that the bone fragment increases the extent of ankylosis in the sheep model. The clinical significance of the various experimental findings of this study and others in the same series is presented.

Short-term effect of deep-frozen stored auricular cartilage allograft repair on the osteoarthritic sheep temporomandibular joint.

The initial effect of deep-frozen stored auricular cartilage replacement was tested on the progression of experimentally induced osteoarthritis in sheep. Bilateral osteoarthritis was induced in the sheep temporomandibular joint. Three months later, discectomy and deep-frozen auricular cartilage allograft repair were performed unilaterally, with the other side being left as a control. Six months post induction of osteoarthritis, 3 months post repair, the sheep were killed. The stored auricular cartilage allografts were not firmly attached to the surrounding tissue and tended to be markedly thinned and perforated. The effect of storage detrimentally affected the properties of the graft.

An infected congenital commissural lip fistula. Report of a case.

A case of infected congenital commissural lip fistula is presented. It appeared as a cheek swelling associated with inflammation due to infection. This case was treated with antibiotics and surgical drainage through the fistula. Our experience suggests that the possibility of infection of the fistula should be considered particularly in cases involved with angular stomatitis and/or scratching injury close to the commissure of the lips.

The role of the disk in sheep temporomandibular joint ankylosis.

OBJECTIVE: The purpose of this study was to determine the role of the disk in intraarticular ankylosis of the temporomandibular joint. STUDY DESIGN: Twelve adult sheep were divided into 2 groups. In group 1, removal of the temporal and condylar articular surfaces was performed on the right temporomandibular joint and the disk was maintained; in group 2, removal of the articular surfaces and diskectomy were performed on the right temporomandibular joint. One sheep from each group was killed just after surgery and 5 sheep from each group were killed at 3 months. The joints were examined radiologically, macroscopically, and histologically. The range of jaw movements was recorded preoperatively and at sacrifice. RESULTS: Each of 2 sheep in group 2 had lost 4% of their body weight by 3 months; all of the other sheep maintained or increased their weight. The range of jaw motion to the right was significantly lower in group 2 than in group 1 (P<.01). In group 1, fibrous repair of the articular surface and regeneration of the condylar head was seen. In group 2, each of the joints showed a total fibrous ankylosis with some calcification. There was a statistically significant difference in radiologic score between the groups (P<.0001). Histologic scores for group 1 demonstrated significantly lower scores on the degree of ankylosis scale and degree of calcification scale (P<.0001). CONCLUSIONS: This study showed that the presence of the disk prevented the development of fibrous intraarticular ankylosis of the temporomandibular joint.

Osteosarcoma metastatic to the mandible: a case report.

A case of osteosarcoma that metastasized to the mandibular ramus from the femur in a 36-year-old man is presented. The patient was referred to us for the diagnosis and treatment of swelling of the left cheek. Radiologic examination showed a radiolucent lesion containing radiopaque areas within the left mandibular ramus. The patient previously suffered from a femoral small cell osteosarcoma, which was resected 71 months before our first examination. After induction of general anesthesia, a unilateral mandibulectomy and a simultaneous reconstruction using a titanium plate and an artificial condyle were performed. The postoperative course was uneventful, with satisfactory facial appearance and jaw function. The histopathologic features of the mandibular tumor were identical to those of the femoral tumor. Thus the mandibular lesion was diagnosed as a metastatic small cell osteosarcoma. At 27 months after the operation there had been no recurrence.

An unusual foreign body in an unerupted supernumerary tooth.

A case of an unusual foreign body (a tip fragment from a plastic chopstick) embedded in one of two unerupted supernumerary teeth in the premaxillary region of a 12-year-old Japanese boy is presented.

Comparison of different methods of temporomandibular joint disc reconstruction--an animal model.

The optimum method of temporomandibular joint (TMJ) reconstruction has not been defined despite numerous surgical treatments and several well controlled clinical trials. Animal models offer an experimental method allowing direct comparison of standardized surgical techniques. Advanced osteoarthrosis was induced bilaterally in 12 mature merino sheep. Three months alter unilateral surgical reconstruction was performed. Four sheep had discectomy alone, four discectomy with fresh TMJ disc grafts, and four discectomy with fresh auricular grafts. All three surgical methods resulted in some reversal and repair of the osteoarthritic process, with the best result being from the auricular graft, next discectomy alone, next the disc graft, with the untreated osteoarthritic joint showing the most advanced pathosis. This study supports the role of surgical reconstruction in advanced degenerative disease of the temporomandibular joint, in particular, auricular graft reconstruction.

Matrix metalloproteinase and tissue inhibitor of metalloproteinase in serum and lavage synovial fluid of patients with temporomandibular joint disorders.

We measured matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMP) in temporomandibular joint (TMJ) disorders. All patients were fully investigated, by visual analogue pain scores, plain radiographs and double-contrast arthrotomograms. The patients were grouped according to whether or not they were in pain. There were 35 patients with painful joints; 16 painless crepitating joints and 10 with chronic closed locked joints. A further group of 9 volunteers with no symptoms of TMJ abnormalities were used as controls. We found that synovial fluid concentration of MMP-3 was significantly increased (1117.2 (164.0) ng/ml) (P< 0.05) in the painful group compared with controls (436.2 (94.8) ng/ml) and with the two groups with painless TMJ (475.0 (113. 0) ng/ml/crepitation, and 516.0 (115.1) ng/ml/closed locked joints). MMP-1 and TIMP-1 were not recordable in most joints, and the serum concentrations of MMP-1, MMP-3, and TIMP-1 were similar to those in controls in all groups. There was no correlationship between MMP-3 concentration and joint morphology as shown by plain radiographs and double contrast arthrotomograms. These findings indicate that the synovia of painful joints are inflamed.

Matrix metalloproteinase-2 in synovial lavage fluid of patients with disorders of the temporomandibular joint.

We examined the matrix metalloproteinase-2 (MMP-2) activity in synovial lavage fluid of patients with disorders of the temporomandibular joint (TMJ) and explored the possible correlationship between MMP-2 activity and radiological changes. We studied 86 patients and 10 healthy volunteers. An arthrogram and a double contrast arthrotomogram were taken to evaluate intra-articular morphological changes. The patients were divided into three groups: no abnormality (n = 36), internal derangement (n = 39), and osteoarthritis (n = 11). Samples of synovial fluid were studied by gelatin zymography, and we sought a correlation between the band detected and radiological findings. ProMMP-2 was detected in all samples and active MMP-2 was detected in 9/36 with no abnormality, 14/39 with internal derangement and 5/11 with osteoarthritis. No active form of MMP-2 was detected in the control group. The incidence of active MMP-2 was high in the internal derangement group and highest in the osteoarthritis group, which suggests that active MMP-2 plays an important part in the development of conditions of the TMJ.

Effect of partial immobilization on reconstruction of ankylosis of the temporomandibular joint with an autogenous costochondral graft:an experimental study in sheep.

The purpose of this study was to show the effect of partial immobilization of a costochondral graft reconstruction of an ankylosed temporomandibular joint (TMJ) in five adult sheep. Ankylosis was induced in all right TMJs. At three months, a graft was inserted and partially immobilized. Three months after the second operation, four sheep were killed by an overdose with pentothal. One sheep was killed at one month because of infection. Functionally, the body weight, which decreases with ankylosis, did not recover after insertion of the graft and the range of jaw movements got worse. Histologically, the grafts were well attached to the mandibular rami in three of four joints. In one joint, the graft showed signs of resorption and a foreign body reaction. We conclude that, if the reconstructed joint is partially immobilized, then there will be a degree of reankylosis. There was also a high failure rate.

Effects of a single arthrocentesis and a COX-2 inhibitor on disorders of temporomandibular joints. A preliminary clinical study.

Our aim was to examine the short-term effect of combined treatment with single arthrocentesis and a COX-2 inhibitor on 26 patients with severe symptoms of temporomandibular joint (TMJ) disorders. The severity of the disorders was graded according to the degree of restriction of mouth opening and pain score on a visual analogue scale. Synovial fluid was collected from the superior joint space of the affected TMJ, and arthrocentesis was done with isotonic saline, 200ml. Subsequently, etodolac, 400mg/day, was given for 2 weeks. At 14 days, patients were re-examined and further specimens of synovial fluid were collected. Patients generally lost their symptoms and the severity of the disorders improved significantly (P<0.01). The concentrations of total protein and albumin in synovial fluid decreased with no statistical significance. However, the concentration of matrix metalloproteinase-3 and its ratios to total protein and albumin did decrease significantly (P<0.05). Our results suggest that a larger controlled study is necessary to clarify the contributory effect of arthrocentesis and etodolac for patients with severe symptoms of TMJ disorders.