RESUMO
Purpose: This study aimed to evaluate age-stratified radiographic features in temporomandibular joint osteoarthritis using cone-beam computed tomography. Materials and Methods: In total, 210 joints from 183 patients (144 females, 39 males, ranging from 12 to 88 years old with a mean age of 44.75±19.97 years) diagnosed with temporomandibular joint osteoarthritis were stratified by age. Mandibular condyle position and bony changes (flattening, erosion, osteophytes, subchondral sclerosis, and subchondral pseudocysts in both the condyle and articular eminence, thickening of the glenoid fossa, joint space narrowing, and joint loose bodies) were evaluated through cone-beam computed tomography. After adjusting for sex, the association between age groups and radiographic findings was analyzed using both a multiple regression model and a multinomial logistic regression model (α=0.05). Results: The prevalence of joint space narrowing and protruded condyle position in the glenoid fossa significantly increased with age (P<0.05). The risks of bony changes, including osteophytes and subchondral pseudocysts in the condyle; flattening, erosion, osteophyte, and subchondral sclerosis in the articular eminence; joint loose bodies; and thickening of the glenoid fossa, also significantly rose with increasing age (P<0.05). The number of radiographic findings increased with age; in particular, the increase was more pronounced in the temporal bone than in the mandibular condyle (P<0.05). Conclusion: Increasing age was associated with a higher frequency and greater diversity of bony changes in the temporal bone, as well as a protruded condyle position in the glenoid fossa, resulting in noticeable joint space narrowing in temporomandibular joint osteoarthritis.
RESUMO
Glucosyltransferase-B (GTFB) of Streptococcus mutans is considered a virulence factor because of its activity in the production of insoluble glucan, which is key to the bacterial attachment onto dental surfaces, leading to the formation of dental caries. Local passive immunization with monoclonal antibodies against GTFB is considered to be an effective way to prevent dental caries. Here we amplified a 1.3 kb fragment of the N-terminal half of the gtfB gene (193-1530) of S. mutans by PCR and expressed the truncated protein (GTFBN). The expressed, purified protein was used as an immunogen in BALB/c mice. We selected and established one hybridoma (HBN8) that was capable of producing anti-GTFBN using ELISA, dot blot, and Western blot analyses. The monoclonal anti-GTFBN antibody was purified by affinity chromatography and its isotype was confirmed as IgG2a. The anti-GTFBN antibody inhibited the enzymatic activity of crude glucosyltransferase of S. mutans GS-5 in a dose-dependent manner. These data suggest that the anti-GTFBN antibody could be used as a vaccine to prevent the aggregation of S. mutans on tooth surfaces, and thus prevent the formation of dental caries.