Silicone-induced foreign-body reaction after temporomandibular joint arthroplasty. Case report

Suture-induced arthritis as a clinical mimicker of septic arthritis

Foreign body-induced arthritis is a rare etiology of mono-arthritis. It should be suspected in the case of postoperative arthritis, even if some decades have passed since surgery. Histopathology of the tissues is required for a definitive diagnosis, and debridement is essential for complete recovery.

Outcomes of treatment with custom-made temporomandibular joint total joint prostheses and maxillomandibular counter-clockwise rotation

The first 25 consecutive patients with high occlusal plane angulation, dysfunction, and pain who were treated with temporomandibular joint (TMJ) total joint prostheses and simultaneous maxillomandibular counterclockwise rotation were evaluated before surgery (T1), immediately after surgery (T2), and at the longest follow-up (T3) for surgical movements and long-term stability. Subjective ratings were used for patients' facial pain/headache, TMJ pain, jaw function, diet, and disability, and objective functional changes were determined by measuring maximum incisal opening and lateral excursive movements. Results showed that the areas of greatest surgical change included an average decrease in the occlusal plane of 13.3 degrees with advancement at point B of 13.4 mm and at the genial tubercles of 16.3 mm. At longest follow-up, relapse was 0.7 degrees, 0.8 mm, and 1.2 mm, respectively, with no statistically significant changes. Significant subjective pain and dysfunction improvements were observed (P ≤ 0.001). Maximum incisal opening increased, but lateral excursion decreased. Those who had two or more previous TMJ surgeries showed greater levels of dysfunction at T1 and T3 than those who had one or no previous surgeries, but otherwise patients presented similar amounts of absolute changes. In conclusion, end-stage TMJ patients can achieve significant improvement in their pain, dysfunction, dentofacial deformity, and airway problems in one operation with TMJ reconstruction and mandibular advancement using TMJ custom-made total joint prostheses and simultaneous maxillary osteotomies for maxillomandibular counter-clockwise rotation.

Long-term outcomes after total alloplastic temporomandibular joint reconstruction following exposure to failed materials

PURPOSE

Total alloplastic temporomandibular joint (TMJ) reconstruction is often necessary because of the significant bony destruction resulting from failed Proplast-Teflon (Vitek, Houston, TX) and/or Silastic (Dow Corning, Arlington, TX) foreign body inflammatory reactions. Multiply operated and functionless, TMJ patients likewise have undergone total alloplastic reconstruction. Many of these patients were also exposed to failed TMJ implant materials. It was the purpose of this study to evaluate a population representative of both these groups of patients reconstructed with the Techmedica (now, TMJ Concepts, Ventura, CA) Total TMJ System to determine whether the long-term subjective and objective outcomes were affected by either the presence of the previously failed TMJ implant materials, the number of prior procedures, or both.

PATIENTS AND METHODS

One hundred ninety-eight patients who had been implanted with 332 Techmedica System total joints between 1990 and 1994 where divided into 4 groups based on their prior exposure to failed TMJ implant materials: group I, Proplast-Teflon (82 patients, 135 joints); group II, Silastic (28 patients, 46 joints); group III, both Proplast-Teflon and Silastic (25 patients, 46 joints); and group IV, no prior exposure to Proplast-Teflon or Silastic (63 patients, 105 joints). The mean follow-up was 60.2 +/- 40.3 months (range, 2 to 120 months). To determine whether exposure to either or both failed implant materials affected the long-term subjective and objective outcome variables, the groups were compared statistically using multivariate mixed modeling with age, sex, number of prior operations, years with TMJ problem, prior implant type, and implant sides as independent variables, and the relevant baseline measure as covariates.

RESULTS

For the subjective variables, patients exposed to Proplast-Teflon or Silastic had significantly higher mean pain scores long-term. The type of prior failed TMJ implant material was not statistically significant with regard to function. Patients exposed to Proplast-Teflon reported poorer diet consistency scores long-term. Objectively, patients with 5 or fewer prior TMJ surgeries exposed to neither failed implant or Silastic reported better long-term mean maximum interincisal opening than did those patients exposed to Proplast-Teflon or both failed materials. However, for patients with 6 or more prior TMJ surgeries, those exposed to Proplast-Teflon or both failed materials reported less decrease in mean maximum interincisal opening over time.

CONCLUSION

These data confirm what has been observed clinically, that in the population studied, multiply operated patients previously exposed to failed Proplast-Teflon alone or both failed Proplast-Teflon and Silastic have poorer reported long-term outcomes with alloplastic reconstruction. However, the total alloplastic TMJ reconstruction devices used in this study remained functional.

Gelatin-glutaraldehyde cross-linking on silicone rubber to increase endothelial cell adhesion and growth

Silicone is a biomaterial that is widely used in many areas because of its high optical clarity, its durability, and the ease with which it can be cast. However, these advantages are counterbalanced by strong hydrophobicity. Gelatin cross-linking has been used as a hydrophilic coating on many biomaterials but not on silicone rubber. In this study, two gelatin glutaraldehyde (GA) cross-linking methods were used to coat a hydrophilic membrane on silicone rubber. In method I, gelatin and GA were mixed in three different proportions (64:1, 128:1, and 256:1) before coating. In method II, a newly formed 5% gelatin membrane was cross-linked with a 2.5% GA solution. All coatings were hydrophilic, as determined from the measurement of contact angle for a drop of water on the surface. Bovine coronary arterial endothelial cells were shown to grow well on the surface modified by method II at 72 h. In method I, the cells grew well for gelatin-GA proportions of 64:1 and 128:1 at 72 h. No cell attachment on untreated silicone rubber was observed by the third d of seeding. The results indicated that both methods of gelatin-GA cross-linking provided a hydrophilic surface on silicone for endothelial cell adhesion and growth in vitro.

Surgical treatment of TMJ ankylosis: our experience (60 cases)

Limitation of mouth opening can be caused by bony or fibrous ankylosis of the temporomandibular joint as sequela to trauma, infection, autoimmune disease, or failed surgery. Various procedures have been reported for treatment of temporomandibular joint (TMJ) ankylosis; this article aims to describe the diagnostic protocol and the surgical procedures adopted at the department of Maxillo-Facial Surgery of Rome University "La Sapienza". Between 1980 and 2000, 123 patients affected by TMJ ankylosis came under our observation; 60 of them (25 females and 35 males of 30 years average age) underwent surgery; bilateral TMJ ankylosis was observed in 21 cases, right-sided in 20 cases, left-sided in 19 cases. In 12 cases coronoid processes were involved. Etiopathogenesis was traumatic in 48 cases, septic in 5 cases, auto-immune (RA and seronegative spondyloarthropathies) in 5 cases; after block removing, arthroplasty was performed with pedunculated flap of temporal muscle (10 cases), Silastic material (11 cases), or lyophilized dura mater (2 cases). Simple condylar shaving was used in the remaining 36 cases. All patients under treatment showed a distinctive improvement both in articular functionality and symptoms; secondary surgery was necessary in seven cases due to the onset of articular complications from previous surgery. Silastic removal was necessary in five cases due to its inducement of foreign body granuloma. Follow-up was performed at 12, 24, and 48 months and 5 years postoperatively. In our opinion the gold standard surgery of TMJ ankylosis today is represented by shaving of articular surfaces and subsequent arthroplasty with or without temporal muscle myofascial flap interposition, whereas the use of Silastic as alloplastic material could be associated to an increased persistence of the local symptoms and a higher risk of foreign body granuloma and it may favor ankylosis relapse and hinder rehabilitation.

Silicone-associated tissue reaction: a dilemma for oral and maxillofacial surgeons

A case report of cystic encapsulation of a silicone elastomer (Silastic: Polydimethyl Siloxane, Dow Corning Ltd) orbital floor implant is described. This is a known, but poorly understood complication of implanted silicone elastomer. Comparison is made with other complications associated with Silastic, and attention drawn to the phenomenon of excessive collagen formation demonstrated by the thick collagen cyst lining, analogous to fibrous 'cricket ball' breast implant encapsulation, which may be peculiar to certain predisposed individuals.

In vivo experimental analysis of silicone implants on bone and soft tissue

We report experimentally produced silicone microparticles (synovitis) in 47 white rabbits and discuss the implications for clinical practice. Silastic HP100 (Dow Corning Wright, Arlington, TN) finger hinges (size 5) were inserted in 20 rabbit's knees. The upper tibia was replaced with Swanson design great toe implants in another 15 rabbits; articular cartilage was removed and endosteal drilling was performed in 6 animals as a "sham" arthroplasty. Small silicone blocks were inserted in the proximal tibial endosteal canal of 6 others. Animals were followed by monthly x-ray films and killed at 2, 4, 6, 12, and 16 months. Implant wear, bone surfaces, and soft tissue were examined under the operating microscope and by light microscopy; implant surfaces were examined with scanning electron microscopy. X-ray changes included reactive endosteal bone formation around implant stems as early as 1 month postoperatively; at 2-3 months the new bone line was clearest but it became progressively homogeneous and less evident. Extensive cortical erosion around the stems was observed in one third of the animals. Neither ossification nor lysis was observed around the silicone block. Proliferative synovitis was found at post-mortem examination beginning after 4 months; femoral condylar erosions were observed in most animals after 12 months. Wherever there was bone destruction, silicone particles were confirmed by x-ray spectrography.

Temporomandibular joint reconstruction of the complex patient with the Techmedica custom-made total joint prosthesis

A study of 56 patients (55 female, one male) with 100 reconstructed temporomandibular joints (TMJ) using the Techmedica custom-made total joint system (Techmedica Inc, Camarillo, CA) is presented. The patients ranged in age from 15 to 61 years (average, 39 years) and had 16 to 46 months' follow-up (average 30 months). Outcome groups were categorized as good, fair, or poor, based on clinical assessment. Results show that 35 patients (63%) with 58 joints (58%) had a good outcome, and 13 patients (23%) with 26 joints (26%) had a fair outcome, and 8 patients (14%) with 16 joints (16%) had a poor outcome. Patients with one or no previous temporomandibular joint surgeries had 86% in the good group, 14% in the fair group, and no patients in the poor group. In patients with two or more previous surgeries, the success rate decreased to 55% with good results, 26% with fair results and 19% with poor results. Long-term morbidity included five ramus prostheses that were removed or revised. Seventeen patients (30%) received further operations because of heterotopic bone formation, fibrosis, calcification, inflammation, and/or pain which occurred mostly in patients with previous Proplast/Teflon (Vitek, Inc, Houston, TX) implants. Continued pain has been associated with the poor group, which may be related to problems such as cervical neuropathy, sympathetic dystrophy, a residual inflammatory or immunologic reaction to Proplast/Teflon or silastic particles, fibrosis, calcification, heterotopic bone, or other unidentified factors.

Temporomandibular joint diskectomy. No positive effect of temporary silicone implant in a 5-year follow-up

The purpose of this study was to evaluate the long-term clinical and radiologic effects of a temporary silicone implant after diskectomy of the temporomandibular joint. Forty-three temporomandibular joints in 43 patients with painful disk displacement underwent a diskectomy. A sheet of medical-grade silicone was temporarily placed in 22 patients; 21 patients did not receive an implant. The patients were clinically and radiologically examined 5 years after surgery. On the basis of symptoms and jaw function, they were classified as having good (30 patients), acceptable (8 patients), and bad (5 patients) results. All the patients with bad results and five of the eight patients with acceptable results had received implants. Erosive changes of the condyle or fossa were seen radiographically at follow-up in eight patients, each of whom had received an implant. No positive clinical or radiologic effects of the implants could be identified. The use of a temporary silicone implant after diskectomy of the temporomandibular joint in patients with internal derangement should be seriously questioned.

The treatment of temporomandibular joint internal derangements using a modified open condylotomy: a preliminary report

A modified open condylotomy was used to treat 44 patients who presented with painful temporomandibular joints, and in whom the clinical and arthrographic findings were indicative of disc displacement. A total of 64 joints (20 bilateral) were operated on. Postoperatively, the patients showed an overall improvement in their functional symptoms. Ninety-one percent of patients had improvement in clicking and popping, and 96% reported decrease in locking. Complaints related to pain and headache were improved 85% and 95%, respectively. The modified technique, as well as the anatomic basis for its use, are discussed.