A Comparative Mixed Longitudinal Evaluation of Doxycycline Solution as an Aligner Rinse Compared With Conventional...

Clear aligners are vulnerable to microbial colonization, discoloration, and inflammation-associated delays in orthodontic tooth movement. This study explores the use of sub-antimicrobial-dose doxycycline as a novel aligner disinfectant, owing to its combined antimicrobial, anti-inflammatory, and osteogenic effects.

This study aims to compare the clinical, microbiological, and biological efficacy of 0.1% doxycycline solution versus 0.2% chlorhexidine gluconate in aligner therapy.

A mixed longitudinal cohort design was employed, enrolling 60 patients undergoing aligner therapy. Participants received alternating aligners soaked in doxycycline (group A) and chlorhexidine (group B). Clinical indices, colony-forming units (CFUs), gingival crevicular fluid (GCF) alkaline phosphatase (ALP), and aligner transparency were evaluated at baseline, two weeks, one month, three months, and six months. Random allocation was performed using a computer-generated sequence. Outcome assessors were blinded. Microbial cultures, ALP assays, and spectrophotometric evaluations were conducted using standardized protocols.

Group A exhibited significantly lower plaque and gingival indices, reduced CFUs, enhanced aligner clarity, and elevated ALP levels compared to group B (p < 0.01). Pearson's correlation showed a strong inverse relationship between ALP and both CFUs and the gingival index.

Doxycycline demonstrated superior microbial control, esthetic maintenance, and biological stimulation, supporting its potential role as a dual-action adjunct in aligner-based orthodontics. Further multicenter studies are recommended to validate these findings.