Digital vs Conventional VFR in Post-Orthodontic Retention

Orthodontic retention is essential to prevent relapse following active orthodontictreatment, and vacuum‐formed retainers (VFRs) are widely used due to their aesthetics andease of fabrication.Conventional VFRs are fabricated over a plaster model derived from alginate impressions,while digital VFRs are fabricated over a 3D‐printed model generated from an intraoralscan.This randomized clinical trial compares periodontal health outcomes; Plaque Index,Gingival Index, and Periodontal Pocket Depth, between the two fabrication methods.Fifty‐two participants (26 per arm) aged 15‐30 years who have completed non‐extractionfixed orthodontic treatment on both arches within the last month will be enrolled vianon‐probability consecutive sampling. Group A will receive digitally fabricated VFRs;Group B will receive conventionally fabricated VFRs, both made of 1.5 mm PETG material.Participants will wear retainers 22 hours daily and follow standardized oral hygieneinstructions.Periodontal parameters will be assessed on index teeth 16, 21, 31, and 46 at baseline(T0) and at 1, 3, and 6 months (T1‐T3) post‐placement. Gingival Index will follow the Loeand Silness method; Plaque Index will follow the Silness and Loe method; pocket depthwill be measured with a UNC‐15 probe at six sites per tooth.Data will be analyzed in SPSS v27 using independent‐sample t‐tests/Mann‐Whitney U testsfor between‐group comparisons and paired t‐tests for within‐group change from baseline,with stratification for age and gender as effect modifiers.