Fixed Orthodontic Retainer

After completion of orthodontic treatment, a retention phase is required to prevent relapse of tooth malposition. Fixed retention in the mandibular anterior region is commonly used. This type of retainer is bonded to the lingual surfaces of the canines and incisors and may hinder oral hygiene, thereby promoting bacterial plaque accumulation and gingival inflammation. Currently, probably due to the increasing use of clear aligner therapy, clear removable Essix-type retainers are becoming more widely used. Since these retainers can be removed by the patient, they may facilitate oral hygiene. However, studies assessing gingival health and the composition of the subgingival microbiota in patients wearing orthodontic retainers remain scarce. Therefore, the aim of this study will be to assess the composition of the gingival sulcus microbiota and gingival health in patients wearing fixed or removable orthodontic retainers. Ten adult patients who have completed orthodontic treatment will be recruited and divided into two groups: 1. Fixed retention group. 2. Removable retention group. Periodontal parameters will be assessed, and bacterial plaque samples will be collected from the gingival sulcus at five time points: T0: Bracket removal and dental scaling appointment. Periodontal parameters will be assessed, and plaque samples will be collected before bracket debonding and dental scaling. T1: Retainer placement appointment, three days after T0. Periodontal parameters will be assessed, and plaque samples will be collected before retainer placement. T2: One month after retainer placement. T3: Three months after retainer placement. T4: Six months after retainer placement.

The main goal is to test the differences between the retentive capacity of fixed retainer, vacuum-formed retainer \& combination of both; and recommend the most effective protocol for retention of lower incisors crowding treated by non-extraction treatment plan The main question is: In patients with lower incisors crowding treated by non-extraction treatment plans, what is the difference in retentive capacity between fixed retainer, vacuum formed retainer and combined bonded and vacuum retainers in maintaining corrected lower anterior segment crowding? After enrolment, each participant will have the orthodontic appliance debonded, the adhesive remnant removed and the enamel surface polished. An alginate impression will be taken to be poured into a study model which will be scanned to obtain STL files for digital models. All patients will have periodontal charting and probing depths recorded for the lower anterior segment. According to the randomization, each patient will be assigned to a group to receive the retainer. All patients will be called for follow-up after 1 week, 1 and 3 months.