The goal of this clinical trial is to learn if a personalized Digital Oral Health Intervention (DOHI) improves how well adults follow recommended tooth brushing routines. Researchers also aim to understand which factors influence the success of the intervention.

The main questions this study will answer are:

Does using the DOHI lead participants to brush twice daily for two minutes, covering all four quadrants (the 2x2x4 routine) more consistently than traditional oral hygiene instructions alone?

Which participant characteristics, such as demographics or baseline oral hygiene habits, affect how well the DOHI helps people improve their brushing?

How does engagement with the digital coaching and technology impact adherence to recommended oral hygiene practices?

In this study:

230 adults receiving care at community dental clinics in California will participate.

Everyone will begin with a 2-week run-in period using traditional oral care instructions.

Afterward, participants will be randomly assigned to one of two groups:

The control group will continue with traditional oral hygiene instructions.

The intervention group will receive traditional oral hygiene instructions plus personalized digital coaching delivered through a mobile app and an electronic toothbrush system.

The DOHI provides personalized feedback, educational content, and motivational prompts that adapt over time based on each participant's brushing behavior and engagement.

Both groups will use an electronic toothbrush to objectively record when, how long, and how well they brush.

Participants will:

Follow the assigned oral hygiene instructions for 19 weeks.

Use an electronic toothbrush and mobile app as instructed.

Have their brushing data automatically collected and analyzed by researchers.

The study will look at changes in brushing frequency and duration from before to after the intervention. Researchers will also explore how personal characteristics and engagement with technology influence outcomes.

The results of this trial will help community dental clinics know if personalized, digital coaching can help more adults maintain healthy habits and achieve better oral health, and guide future improvements in digital health interventions for oral hygiene.

This multisite randomized controlled trial is designed to evaluate whether a personalized Digital Oral Health Intervention (DOHI) can improve adherence to recommended oral hygiene behaviors compared to traditional oral hygiene instruction alone. The study addresses the persistent challenge of maintaining long-term oral hygiene habits by utilizing technology-facilitated coaching, adaptive intervention delivery, and reinforcement learning algorithms that respond to each participant's real-time brushing behaviors.

A total of 230 adults (aged 18 years and older) will be recruited from three community dental clinics in California: Dientes Community Dental Care (Santa Cruz County), Petaluma Health Center (Sonoma County), and University of California, Los Angeles (UCLA)Dental Clinics (Los Angeles County). Following baseline education in the recommended 2x2x4 brushing protocol (brushing twice daily for two minutes, covering all four dental quadrants) and a 2-week run-in period to ensure comfort with the electronic toothbrush system and study procedures, eligible participants will be randomized in equal numbers to either the intervention or control group.

Participants in the control group will continue with traditional oral hygiene instruction and receive standard feedback on their brushing patterns over the 19-week intervention period. The intervention group will also receive traditional instruction and standard feedback, but in addition they will be provided with personalized digital coaching through the DOHI platform. The DOHI integrates an electronic toothbrush and the Oralytics mobile application to deliver tailored feedback, educational resources, and motivational strategies such as micro-incentives. The system uses reinforcement learning algorithms to dynamically adjust the timing, frequency, and content of coaching prompts based on each participant's brushing data and engagement patterns, aiming to optimize involvement and support sustainable behavior change.

The primary outcome of the study is the change in participants' adherence to the recommended brushing frequency and duration, objectively measured from baseline through 19 weeks using data collected by the electronic toothbrush system. Secondary outcomes include analyses of individual-level factors-such as demographics, initial oral hygiene behaviors, and patterns of technology use-that may influence the effectiveness of the DOHI for promoting oral self-care.

The results of this trial are expected to provide evidence for the implementation of adaptive digital interventions to support oral health, with the potential for broad application in community dental care settings.

Inclusion Criteria:

• Adults aged 18 years and older
• Fluent in English (speaking, reading, writing)
• Dentulous or partially edentulous (minimum 2 teeth per quadrant)
• Own and regularly use a smartphone (iOS or Android) with active data plan
• Receiving dental care at a participating study site
• Willing to use electronic toothbrush and mobile application for 19 weeks
• Able to provide informed consent

Exclusion Criteria:

• Edentulous (no natural teeth)
• Fewer than 18 teeth or fewer than 2 teeth in any quadrant
• Unable to use mobile devices due to cognitive or physical impairments
• Unwilling to comply with study procedures
• Current participation in another oral health intervention study

A de-identified dataset will be made available to the research community 12 months after publication of primary analyses. External data requests require written proposals and institutional oversight documentation, subject to confidentiality agreements and Principal Investigator approval.

Data will be available beginning 12 months after publication of primary results and ending 5 years after article publication

Requests for data access require written scientific proposals, institutional oversight documentation, and signed data use agreements. Requests will be reviewed by the Principal Investigator and institutional data sharing committee."