An immunohistochemical study was performed on the articular disk and periarticular tissues of the temporo-mandibular joint (TMJ) in order to ascertain the presence of neuroreceptors (NRec) in these sites. The study was carried out with the APAAP technique on tissue samples obtained from 10 subjects without known TMJ disease and from 5 patients with severe TMJ arthritis or arthrosis. The antibodies used were directed against the following antigens: Gliofibrillary Acidic Protein (GFAP), Leu-7, Myelin Basic Protein (MBP), Neurofilaments 68 kD (NF), Neuron Specific Enolase (NSE), S-100 protein (S-100) and Synaptophysin (SYN). This study revealed that Ruffini's-like, Pacini's-like and Golgi's-like receptors can be demonstrated in TMJ periarticular tissues and that free nervous endings are present in the subsynovial but not within the articular disk. In the latter, elongated cytoplasmic processes of chondrocytes demonstrated strong S-100 immunoreactivity but they were unreactive with all other antibodies. These cytoplasmic processes were more abundant and thicker in the samples obtained from patients with diseased TMJ. The results of this study confirm that different NRec are detectable in TMJ periarticular tissues but they are absent within the articular disk. In the latter site, only chondrocytic processes are evident, especially in diseased TMJ, and they might have been confused with nervous endings in previous morphological studies. Nevertheless the absence of immunoreactivity for NF, NSE and SYN proves that they are not of neural origin.