A randomized controlled trial of home-applied dual-light photodynamic therapy during supportive periodontal care (HOPE-CP study)

Background: Periodontitis is a common, chronic inflammatory disease that relies heavily on effective daily oral hygiene for long-term control. Light-based therapies have demonstrated strong antibacterial potential; however, their effectiveness in regular home use remains unexplored. Methods: Two hundred stage I–III periodontitis maintenance patients were randomized for supportive periodontal care (SPC) or SPC combined with adjunct home-applied dual-light therapy. Bleeding on probing (BOP), visible plaque index (VPI), and the number of sites with ≥4 mm periodontal probing depth (PPD) were measured at the baseline, at 3 and 6 months. Results: Of the 200 randomized patients, 184 completed all visits. At baseline, the groups were similar for BOP, VPI, and pocket depth. At 3 and 6 months, adjunctive dual-light therapy achieved lower BOP (12.6 ± 0.7% and 12.0 ± 0.8%) than SPC alone (17.8 ± 0.8% and 17.3 ± 1.0%); p < 0.0001 and p = 0.0002 and lower VPI (8.5 ± 0.7% and 9.7 ± 0.8%) vs. (13.3 ± 0.8% and 14.2 ± 1.0%); p < 0.0005 and 0.0142. The dual-light group also had fewer sites with PPD ≥ 4 mm (5.6 ± 0.7 and 5.3 ± 0.6) vs. (7.6 ± 1.2 and 7.8 ± 0.9); p = 0.02 and p = 0.02. Conclusion: Regularly home-applied dual-light therapy may represent a promising addition to existing home-care strategies and a potential advance in adjunctive periodontal maintenance. Plain language summary: Periodontitis is a common disease that damages the tissues supporting the teeth. Daily brushing and cleaning between the teeth are essential, but even with good routines, people can still develop plaque and gum inflammation. Light-based treatments are known to eliminate plaque bacteria effectively, but until now, they have mostly been used in dental offices, and their potential for home use has not been tested. In the HOPE-CP study, we enrolled 200 adults with periodontitis to receive routine supportive periodontal care. Half of them were randomized to use a light-based antibacterial device to support their daily oral hygiene at home. After 3 and 6 months, those using the device had less gum bleeding, less visible plaque, and fewer sites with deeper periodontal pockets than those who used routine care alone. These results show that using a daily antibacterial light treatment at home may help people better control inflammation and maintain healthier gums between dental visits.