Effect of a Modified Surgical Protocol for Immediate Dental Implant Placement on the Oxidative–nitrosative Balance of Human Saliva

Objective. To evaluate the effect of a modified surgical protocol for immediate dental implantation using a collagen cone on the oxidative–nitrosative balance of patients’ saliva. Materials and methods. The study involved 46 patients divided into four groups: a control group, patients with dentition defects requiring prosthetic rehabilitation, patients who underwent immediate dental implantation using the conventional protocol, and patients treated using the modified protocol. Samples of unstimulated whole saliva were analyzed to determine total nitric oxide synthase (NOS) activity, inducible and constitutive NOS activities, arginase activity, nitrite concentration, superoxide dismutase and catalase activities, as well as malondialdehyde and hydrogen sulfide levels. Results. Dentition defects were found to be associated with the development of oxidative–nitrosative imbalance, manifested by decreased total NOS and inducible NOS activities, reduced antioxidant enzyme activity, lower nitrite and hydrogen sulfide concentrations, and increased malondialdehyde levels. The conventional immediate dental implantation protocol resulted in partial restoration of antioxidant defense, as evidenced by increased catalase activity, decreased malondialdehyde concentration, and elevated hydrogen sulfide levels; however, it did not provide significant recovery of L-arginine-dependent nitric oxide production. The modified protocol using a collagen cone produced a statistically significant increase in total and inducible NOS activities, arginase activity, nitrite concentration, superoxide dismutase and catalase activities, together with a more pronounced reduction in malondialdehyde levels compared with the conventional technique. In addition, a substantial increase in hydrogen sulfide concentration was observed, indicating enhanced antioxidant defense and normalization of local regulatory mechanisms involved in tissue repair. Conclusions. The modified immediate dental implantation protocol incorporating a collagen cone restores NO-mediated regulation and antioxidant defense of the oral cavity more effectively than the conventional technique. Further research should focus on investigating the relationship between the observed biochemical changes and long-term clinical outcomes, as well as the processes of osseointegration.