DISCUSSION
malocclusion, bleeding, redness, inflammation, Calculus, edema, hypertrophy, biasness, Bleeding, calculus
BLEEDING, SUBGINGIVAL CALCULUS, INFLAMMATION, MINOR, EDEMA, RECRUITMENT, HYPERTROPHY, BLIND, PLAQUE, BLEEDING
In this randomized trial, the effects of two frequently used fixed lingual retainers on the periodontium health were determined and compared, using different indices. All cases selected were treated non-extraction in the mandibular arch, to minimize the biasness due to difference in treatment philosophy. When baseline demographic factors such as age, sex and type of malocclusion were compared, no statistically significant differences were found between the two groups, confirming that these factors did not affect the results of the study. FRC is accessible in varying widths and forms, including braided and woven polyethylene fibers. In this study, woven polyethylene fibers were used. The results of this study indicate that at the beginning of the trial (T0) both groups presented similar healthy periodontal status, suggesting adequate oral hygiene at the end of fixed orthodontic treatment. However, a continuous deterioration of periodontal health after placement of fixed lingual retainers was observed in the test period. Prolonged use of these retainers favor and attract plaque, lead to calculus deposition, gingival inflammation and bleeding on probing. Most probably, resin tags that extend gingivally favors the precipitation of biofilm, resulting in deposition of plaque and calculus.When the results were compared between the two groups of retainers, no significant differences were established between them. When plaque index was compared, plaque deposits were detected in both groups on probing the gingival margin (score 1) at T1 and T2, followed by visible plaque deposits on the surfaces (score 2) at T3 and T4. No copious amount of plaque (score 3) was detected in both groups. Calculus was seen only on two third of surfaces (score 1) from T1 to T4 in both groups of retainers. Separate specks or uninterrupted bands of subgingival calculus were not noticed. When gingival index was compared between groups, Group 1 (FRC) indicated mild inflammation with minor alteration in color and surface at T1 and T2, and moderate inflammation with reasonable glazing, redness, edema and hypertrophy at T3 and T4. Group 2 (MSW) exhibited mild inflammation, with minor alteration in color and surface throughout. Bleeding on probing was detected in both the groups. The present findings are in accordance with the study conducted by Artun et al,The present study was performed using a prospective design, allowing to evaluate the results in a reliable manner, as compared to retrospective studies, in which data is insufficient and unpredictable. Moreover, it was a multicentre study, involving the recruitment of subjects from different areas, thus providing a representative sample. The limitations included the follow-up time, which was limited to one year (It was not possible to extend the follow-up time of the tria). It was also not possible to blind the observers and the subjects, due to the visible nature of the intervention. Moreover, the findings of this study are limited to one year post-retention, therefore it could not be predicted whether the plaque and calculus deposits could lead to long-term periodontal problems. Other factors such as level of maintenance of oral hygiene and dietary habits could influence the results.It is recommended to conduct similar studies with increased sample size and prolonged duration. Periodontal ligament width changes and bone level should also be evaluated in future. It is also suggested to evaluate the effects of other types of fiber-reinforced composites, such as nano-filled composites.