Salivary pH changes under the effect of stainless steel versus elastomeric ligatures in fixed orthodontic patients: A single-center, randomized controlled clinical trial
Abstract BackgroundFluctuations in pH of saliva during a prolonged treatment course influences the enamel demineralization progress, which is one of the complications of fixed orthodontic treatment. This randomized clinical trial aimed to evaluate and compare the short-term effect of stainless steel (SS) versus elastomeric (EM) ligatures on salivary pH in patients scheduled for fixed orthodontic treatment.MethodsSeventy participants were enrolled in the study (54 females, 16 males) aged 19–36 who met specific inclusion criteria. They were randomly selected and allocated into two equal groups through a computer-generated randomization. All patients received fixed orthodontic treatment using conventional brackets. Two commonly used archwire ligature methods were used: stainless steel and elastomeric modules. An unstimulated (resting) salivary sample was collected before tying of the ligatures at T0 (baseline), 2 weeks, 6 weeks and 12 weeks. Salivary pH was measured using a digital pH meter. The level of significance was set at p value < 0.05.ResultsThe salivary pH level was stable between T0 and T1 (6.72 ± 0.14), then significantly and progressively increased from T1 to T2 (6.78 ± 0.13) and from T2 to T3 (6.81 ± 0.14) with (P < 0.05) in the SS group. In the EM group, the salivary pH level was significantly decreased in all follow-up periods; T0 (6.77 ± 0.16), T1 (6.72 ± 0.14), T2 (6.67 ± 0.13) and T3 (6.64 ± 0.13).ConclusionEM ligature showed a significant decrease in salivary pH to an unfavorable level, which increased the risk of enamel demineralization. Therefore, EM as ligature material is not recommended in patients with high caries index or inadequate oral hygiene.Trial RegistrationANZCTR.org. (ACTRN12618001647224). Registration Date: 5/10/2018, “Retrospectively registered”