CCL28, IL-8, IL-1β and TNF-α may play key roles in the host response to inflammation in periodontal diseases. As the severity of periodontal diseases increases, destruction of periodontal tissues also increases. Inflammation is one among many factors that trigger periodontal tissue destruction. Identification of the mediators that influence the development and progression of inflammation in periodontal diseases may be very important in understanding the prognoses of periodontal diseases.

As a result of the observed vascular and cell activity changes that occur within patients diagnosed with DM, periodontal diseases become more severe. These changes hinder the migration and the ability of chemotactic factors and leukocytes to protect periodontal tissues from the effects of microorganisms. In order to eliminate microorganisms, the epithelial cells in patients with DM may release more hBD-1 and hBD-3 into the gingival crevicular fluid. Determining the amount of hBD-1 and hBD-3 in the gingival crevicular fluid of patients with and without DM will help to elucidate the relationship among hBD-1, hBD-3, DM and periodontal disease.

This study examined the effects of different levels of chronic restraint stress on bone–titanium implant contact in rats. This study included 32 adult female Sprague–Dawley rats. The machined surface titanium implants were surgically placed into the metaphyseal region of the rat tibias. Next, the rats were divided randomly into 4 groups, namely, control (CNT) (n = 8), low-restraint stress (LRS) (n = 8), medium-restraint stress (MRS) (n = 8), and high-restraint stress (HRS) (n = 8) groups. The rats in the CNT group received only the titanium implants surgically but did not receive any further treatment during the experimental period of 30 days. The rats in the LRS, MRS, and HRS groups were applied restraint stress for 1, 2, and 4 hours, respectively, daily for 28 days starting from day 2 after the surgery. At the end of the study period, the rats were sacrificed and their implants and the surrounding bone tissues were harvested for performing nondecalcified histological analysis. Moreover, blood samples were collected from the rats and were centrifuged for analyzing serum cortisol levels. Serum cortisol levels of the rats in the LRS, MRS, and HRS groups were higher than those of the rats in the CNT group (P < 0.05). Moreover, serum cortisol levels of the rats in the HRS group were higher than those of the rats in the MRS and LRS groups (P < 0.05). The extent of bone–implant contact was lower in the rats in the HRS group than in the rats in the CNT and LRS groups (P < 0.05). These data suggest that the application of 4-hour chronic restraint stress during the 28-day experimental period impaired the bone–implant contact.