Changes in essential salivary parameters in patients undergoing fixed orthodontic treatment: A longitudinal study

Objective: Orthodontic treatment using fixed appliances is known to alter the oral environment and encourage plaque retention around orthodontic brackets and bands, resulting in enamel demineralization and gingival inflammation. This study aimed to evaluate the changes in essential salivary parameters in patients undergoing fixed orthodontic treatment. Materials and Methods: Saliva samples were collected from 60 patients before and 2 months after commencing fixed orthodontic treatment. The salivary flow rate, pH, buffering capacity, and levels of amylase, total protein, and glucose were determined. Parametric and nonparametric tests for paired samples were used for comparing the mean differences before and after commencing treatment. Results: Significant reductions in the salivary flow rate, pH, and buffering capacity were noted 2 months after commencing treatment (P < 0.05). Total protein concentrations and calcium levels decreased significantly and amylase and glucose levels increased after commencing treatment (P < 0.05). Significant correlations were observed between salivary total protein concentrations and buffering capacity as well as calcium levels (P < 0.05). Conclusion: These findings indicate that the biochemical properties of saliva are altered after introducing fixed orthodontic appliances into the oral cavity, thereby promoting plaque retention and increasing the susceptibility to tooth demineralization and gingival inflammation.