AimTreatment of periodontitis, a chronic inflammatory disease driven by biofilm dysbiosis, remains challenging due to patients' poor performance and adherence to the necessary oral hygiene procedures. Novel, artificial intelligence‐enabled multimodal‐sensing toothbrushes (AI‐MST) can guide patients' oral hygiene practices in real‐time and transmit valuable data to clinicians, thus enabling effective remote monitoring and guidance. The aim of this trial was to assess the effect of such a system as an adjunct to clinical practice guideline‐conform treatment.Materials and MethodsThis was a single‐centre, double‐blind, standard‐of‐care controlled, randomized, parallel‐group, superiority trial. Male and female adults with generalized Stage II/III periodontitis were recruited at the Shanghai Ninth People's Hospital, China. Subjects received a standard‐of‐care oral hygiene regimen or a technology‐enabled, theory‐based digital intervention consisting of an AI‐MST and targeted doctor's guidance by remote micromessaging. Additionally, both groups received guideline‐conform periodontal treatment. The primary outcome was the resolution of inflamed periodontal pockets (≥4 mm with bleeding on probing) at 6 months. The intention‐to‐treat (ITT) analysis included all subjects who received the allocated treatment and at least one follow‐up.ResultsOne hundred patients were randomized and treated (50 tests/controls) between 1 February and 30 November 2022. Forty‐eight tests (19 females) and 47 controls (16 females) were analysed in the ITT population. At 6 months, the proportion of inflamed periodontal pockets decreased from 80.7% (95% confidence interval [CI] 76.5–84.8) to 52.3% (47.7–57.0) in the control group, and from 81.4% (77.1–85.6) to 44.4% (39.9–48.9) in the test group. The inter‐group difference was 7.9% (1.6–14.6, p < .05). Test subjects achieved better levels of oral hygiene (p < .001). No significant adverse events were observed.ConclusionsThe tested digital health intervention significantly improved the outcome of periodontal therapy by enhancing the adherence and performance of self‐performed oral hygiene. The model breaks the traditional model of oral health care and has the potential to improve efficiency and reduce costs (NCT05137392).