UL Smile app to improve oral health in Portuguese teens

UL Smile - Mobile Application for Oral Health Promotion: Development and Effectiveness Evaluation in Adolescents Living in Portugal: A Randomized Controlled Field Trial

Not applicable Interventional University of Lisbon · NCT07276191

This project will test whether the UL Smile mobile app can improve toothbrushing habits and oral health self-care in Portuguese adolescents aged 15 to 18.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment150 (estimated)
Ages15 Years to 19 Years
SexAll
SponsorUniversity of Lisbon Academic / other
Locations1 site (Lisbon, Lisbon District)
Trial IDNCT07276191 on ClinicalTrials.gov

What this trial studies

The UL Smile program developed a personalized mobile app using a multidisciplinary team and behavior-change frameworks (Behaviour Change Wheel and BCTTv1) to support adolescent oral hygiene. The app includes interactive toothbrushing guidance with audio, video and 3D animations, educational content, gamified badges and achievements, reminders, motivational messages, and a clinician portal for tailored advice. After app development, a parallel-group randomized controlled field trial will be conducted in secondary schools in the Lisbon metropolitan area with entire classes randomly assigned to the app or usual oral hygiene consultations. Outcomes will focus on oral health behaviors, self-efficacy and related clinical indicators among Portuguese-speaking students aged 15–18 who have internet access and agree to use the app.

Who should consider this trial

Good fit: Ideal candidates are Portuguese-speaking adolescents aged 15–18 who have regular access to a smartphone or tablet with internet and are willing to use the app as instructed.

Not a fit: Those unlikely to benefit include adolescents outside the 15–18 age range, individuals not responsible for their own oral hygiene, people without internet-enabled devices, or anyone already using another oral health app.

Why it matters

Potential benefit: If effective, the app could help teenagers build and maintain better toothbrushing routines and reduce future risk of cavities and gum disease.

How similar studies have performed: Previous small trials and pilot studies of mHealth interventions for oral hygiene show promising improvements in brushing behavior and knowledge, but large school-based randomized trials remain limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Be aged between 15 and 18 years at baseline.
* Be fluent in Portuguese.
* Have access to a mobile phone or computer/tablet with internet.
* Be willing to participate in the study by providing signed assent/consent. For participants under 18 years old, consent must be signed by a legal guardian.
* Use of the app at least twice during the first month of the study.

Exclusion Criteria:

* Current or previous use of any oral health-related mobile application.
* Not being responsible for their own oral hygiene.

Where this trial is running

Lisbon, Lisbon District

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Oral Health CareOral Health Behavior ChangeOral Health Self-efficacyAdolescentMobile ApplicationsOral HealthHealth PromotionMHealth
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.