Morphologic and immunohistochemical observation of explanted proplast-teflon temporomandibular joint interpositional implants

Purpose: The objective of this study was to investigate the cellular tissue response to temporomandibular joint (TMJ) Proplast-Teflon disc material by morphologic and immunohistochemical means. Patients and Methods. Twelve patients who had been subjected to TMJ discectomy combined with insertion of a Proplast-Teflon interpositional implant (PTIPI) were recalled for removal of the alloplastic disc. The time elapsed between the Proplast-Teflon disc implantation and its removal varied between 13 and 71 months (mean, 54.6 +/- 5.8 [SEM]) The implants and periimplant tissues were examined by light microscopy and immunohistochemically using a panel of monoclonal antibodies reactive with different subclasses of leukocytes, The sections were immunostained using the alkaline phosphatase-antialkaline phosphatase (APAAP) technique. Results: Fibrosis and a massive foreign body giant cell reaction were seen inside the heavily disrupted alloplastic implants and in the periimplant tissues, CD68-positive monocyte-derived cells dominated the reactive infiltrate in the implants and surrounding tissue, The CD68-positive cells also were partly positive for lysozyme. The lymphocytic infiltration contained no B cells, Conclusions: This study of the PTIPI-induced tissue reaction gave no indication of a toxic or an immunologic pathogenesis. Mechanical stress seems important in the fragmentation of the implant and induction of the foreign body reaction. It is not yet known if this fragmentation is the major contributing factor.