A Mobile App (WhiteTeeth) to Promote Good Oral Health Behavior Among Dutch Adolescents with Fixed Orthodontic Appliances: Intervention Mapping Approach

Background The insertion of fixed orthodontic appliances increases the risk of dental caries, particularly in adolescents. Caries can be prevented through good oral health behavior. To support adolescents with fixed orthodontic appliances and for promoting oral health behavior, we developed a theory- and evidence-based mHealth program, the WhiteTeeth app. Objective The objective of our paper was to describe the systematic development and content of the WhiteTeeth app. Methods For systematic development of the program, we used the intervention mapping (IM) approach. In this paper, we present the results of applying the first 5 steps of IM to the design of an mHealth program: (1) identifying target behaviors and determinants through problem analysis, including a literature search, a survey study, and semistructured interviews, to explore adolescent oral health behavior during orthodontic therapy; (2) defining program outcomes and objectives; (3) selecting theoretical methods and translating them into practical strategies for the program design; (4) producing the program, including a pilot test with 28 adolescents testing the acceptability and usability of the WhiteTeeth app; and (5) planning implementation and adoption. Results On the basis of our literature search, we identified fluoride use and control of dental plaque levels (eg, tooth brushing and proxy brush usage) as target behaviors for preventing caries. Next, we identified important and changeable determinants of oral health behavior that fitted the theoretical concepts of the Health Action Process Approach (HAPA) theory. The HAPA theory, the self-regulation theory, and the results of the semistructured interviews were used to define the program objectives, that is, the performance and change objectives. After defining the objectives, we identified multiple behavior change techniques that could be used to achieve these objectives, such as providing oral health information and feedback, prompting self-monitoring, coaching of set actions and coping plans, and sending reminders. We translated these methods into practical strategies, such as videos and a brushing timer. Next, we combined these strategies into a single program resulting in the WhiteTeeth app (which is available on both iTunes and Google Play stores as “Witgebit”). Adolescents with fixed orthodontic appliances and dental professionals were included in the development process to increase the success of implementation. The pilot test revealed that the app users appreciated and liked the app. The WhiteTeeth app can be integrated into current orthodontic care. Conclusions IM allowed us to identify multiple techniques that have been shown to be the most effective in initiating behavior change, but have not yet been incorporated into existing orthodontic apps. The WhiteTeeth app contains all these techniques, which makes it a unique and promising home-based app for promoting oral health in adolescents with fixed orthodontic appliances.

-Using disclosing tablets to visualize and evaluate dental plaque [3].
-Providing feedback on outcome (BCT 2.7): i.e., monitoring and providing feedback on the outcome of the behavior [1,2].
Adolescents need to possess some sub-skills (they need to know how to use the disclosing tablets and take a selfie).
Feedback needs to be personal and specific.
In the orthodontic clinic (upon installing the app), a dental hygienist demonstrates how to use the disclosing tablets to visualize plaque and how to take a selfie.
To provide feedback, information on adolescents' oral health behavior and dental plaque levels will be collected. Adolescents will first be asked to answer to questions with regard to their oral health behavior. Next, adolescents are asked to use disclosing tablets to visualize the dental plaque. After they use the tablets, they are asked to take a selfie of their teeth with the visualized plaque (red color). The app presents an example of a selfie and the selfie will be stored on the main page of the app. The app asks them to click where the plaque is present on the selfie. Based on the number of clicks and registration questions, the app provides feedback on their dental plaque levels and oral health behavior, and provides oral health advice. Adolescents know what good oral health is and its association with dental plaque (knowledge).
Adolescents acknowledge the risk of not brushing teeth as recommended and its consequences (risk-perception & outcome expectancies).
Adolescents know the benefits of maintaining good oral health (outcome expectancies).
-Belief selection: i.e., using messages designed to strengthen positive beliefs, weaken negative beliefs, and introduce new beliefs [1].
-Providing scenariobased risk information: i.e., providing information that may aid the construction of an image of the ways in future loss or accident There must be a plausible scenario with a cause and an outcome.
The message must be easy to understand: any use of imagery or movies must be relevant and must not diverge too much from the target group's experience.
The app provides information on the importance on tooth brushing as recommended in a short animated movie. The movie explains that not brushing teeth can increase the risk of getting dental diseases (how plaque can cause dental diseases) and can also affect appearance. The movie provides information on the positive outcomes of maintaining good oral health. It shows two scenarios: (1) bad oral hygiene causes white spot lesions/dental caries; (2) good oral hygiene causes white and beautiful teeth. might occur [1].
-Providing reinforcement: i.e., linking a behavior to any consequence that increases the rate, frequency and probability of the behavior [1]. Adolescents know how to brush teeth according to the 5step method (knowledge).
Adolescents feel able to prevent dental diseases and gain confidence in ability to brush teeth twice daily according to the 5step method (action selfefficacy) Adolescents develop toothbrushing skills (5step method) to remove all dental plaque (skills).
-Providing instructions on how to perform the behavior (BCT 4.1): advise or agree on how to perform behavior (includes "skills training') [2].
-Demonstrating the behavior (BCT 6.1): i.e., providing an observable sample of the performance of the behavior, directly in person or indirectly (e.g. through film) (includes "modeling" [1,2]. The adolescents must identify with the model (use a coping model instead of mastery model).
The app provides a movie in which a peer model (adolescent with fixed orthodontic appliances) demonstrates how to brush teeth correctly twice daily according to the 5-step method. The demonstration is tailored to the kind of toothbrush they use, i.e., electric or manual.

PO2
Adolescents choose/plan how to improve their tooth-brushing behavior.

Theoretical methods/ BCTs
Theoretical requirements

Practical strategies
Adolescents choose a change about which they feel selfefficacious (goalcommitment & action selfefficacy).
-Prompting intention formation: i.e., encouraging the person to decide to act or set a general goal [27].
-Setting graded tasks: i.e., setting easy tasks, and increasing difficulty until target behavior is performed [1].
The target behavior can be reduced to easier but increasingly difficult subbehaviors.
The app allows the adolescents to choose the tooth-brushing duration and/or frequency they would like to change and they think they can change.
Adolescents state a clear toothbrushing or oral hygiene goal (skill).
-Goal-setting (behavior) (BCT 1.1): i.e., setting or agreeing a goal defined in terms of behavior to be achieved [2].
Guided by questions in the app, adolescents set a clear goal. The answers are presented as clear goals, which are stored on the main page of the app.

PO3
Adolescents prepare strategies to establish how they will change their tooth-brushing behavior. The app incorporates a program that helps the adolescents to form action plans. Guided by questions in the app, adolescents can specify when and where they will brush their teeth. The answers are presented as their action plan, which will state where and when they will brush their teeth. This includes implementation intentions: prompting making if-then plans that link situational cues with responses that are effective in attaining goals or desired outcomes [1]).
action plan is formulated as an implementation intention ("If situation X arises, then I'll do Y") (The action plan is linked to the option for setting reminders).
Adolescents show commitment to their goals (attitude).
-Behavioral contract (BCT 1.8): i.e., creating a written specification of the behavior to be performed, agreed by the person, and witnessed by another [2].
The app get the adolescent to sign a contract with the toothbrushing goals formulated at a previous stage. This goal (i.e., action plan) will be stored on the app's main page.

PO4
Adolescents change their tooth-brushing behavior. Cues work best when people are allowed to select and provide their own cues.
The app has an option for setting reminders, which are sent as push-notifications that function as "cues to action". The adolescents will be reminded to brush their teeth at a time that fits in with their daily routine.

PO5
Adolescents evaluate their tooth-brushing behavior, their dental plaque levels, and the effect of brushing on these levels. Change objectives (determinant)

Theoretical methods/BCTs
Theoretical requirements

Practical strategies
Adolescents monitor their toothbrushing behavior and dental plaque levels (awareness, self-regulatory skills/action control).
-Self-monitoring of the behavior (BCT 2.3): i.e., the person monitors and records their behavior as part of a behavior change strategy [2].
-Self-monitoring of the outcome of behavior (BCT 2.3): i.e., the person monitors and records the outcome of their behavior as part of a behavior change strategy [2].
Commitment and motivation are required to use the selfmonitoring part of the app.
The data must be interpreted and used.
Upon installing the app in the orthodontic clinic, a dental hygienist briefly shows the adolescent how to monitor their tooth-brushing and dental plaque levels.
Adolescents fill out their toothbrushing frequency in the app every day. If they fail to complete the monitoring, a prompt message is sent the next day. goal(s) jointly with the person and considering modifying goal(s) or behavior change strategy in the light of achievement. This may lead to re-setting the same goal, to a small change in that goal, or to setting a new goal rather than (or in addition to) the first; or to no change [2].
Discrepancy between the current behavior and goal (BCT 1.6): i.e., drawing attention to discrepancies between a person's current behavior (in term of the form, frequency, duration, and intensity of that behavior) and the person's previously set outcome goals or action plans (goes beyond self-monitoring of behavior). recommendation s.
the app provides personal feedback once a week on whether the person's performance corresponds to the agreed goals and asks them to consider modifying goals accordingly.
Adolescents monitor their dental plaque levels (awareness, self-regulatory skills) and compare it with goal (awareness, self-regulatory skills).
-Using disclosing tablets to visualize and evaluate dental plaque [2].
-Prompting selfmonitoring of the outcome of the behavior (BCT 2.4): i.e., establishing a method for the person to monitor and record the outcome(s) of their behavior as part of a behavior-change strategy [2].
-Providing feedback on the outcome of behavior (BCT 2.7): i.e., monitoring and providing feedback on the outcome of the behavior [1,2].
Adolescents need to possess the sub-skill: identifying which dental surfaces are clean and which are covered with dental plaque.
Once a week the app asks adolescents to use disclosing tablets to visualize the dental plaque and to take a selfie of the results (this is the same procedure as during registration). It then asks them to designate the position of the dental plaque on the selfie by clicking on the screen. Based on the number of clicks, the app compares the number of clicks (plaque levels) with the results of the previous week, and provides feedback accordingly. Adolescents feel positive about tooth-brushing (outcomeexpectancies).

PO6
Adolescents believe that longterm benefits can be achieved by maintaining tooth brushing over time (attitude).
-Belief selection: i.e., using messages designed to strengthen positive beliefs, weaken negative beliefs, and introduce new beliefs [1].
-Framing: Using gainframed messages emphasizing the advantages of performing the healthy behavior [1].
Before choosing the beliefs on which to intervene, the individual's current attitudinal, normative, and efficacy beliefs should be investigated. Gain-framed messages are more readily accepted and prevent defensive reactions.
The app provides positive personal text-messages about favorable outcomes and the benefits of tooth brushing, (i.e., personal motives which are asked by the app when starting the app).
BCT: Behavior Change Technique; PO: Performance objectives. * Many methods have clearly been defined, linked with theories of behavior change and classified into internationally recognized taxonomies of behavior-change techniques [1,2]. These taxonomies were used to code the content of the program with standardized definitions of the behavior-change techniques (BCT's) classified by these taxonomies [2].