Few educational oral health applications, directed to the preschool children under the age of six years are available world-wide. The overall aim of this study is to evaluate the acceptance and efficacy of a digital application in improving evidence based oral hygiene knowledge among parents of young children to control Early Childhood Caries (ECC).

This study is split into two parts, the first one is aimed to understand the acceptance, usability and parental perception about a digital application being used to promote the evidence based oral hygiene knowledge among parents of young children to control ECC.

In a second phase (randomised clinical trial) the additional effect and acceptance of the digital application, and efficacy in improving parental knowledge, behaviour and self-reported practices/attitudes related to the oral health preventive measures will be presented.

This two arm randomized cohort study is being undertaken at the Department of Preventive and Pediatric Dentistry at the University of Greifswald. Assessment of eligibility and application of intervention will be carried out by a single investigator (JH).

This study is being conducted in total in two phases. In the first, pilot phase - the digital application design, acceptance and parental perception will be assessed with the help of a questionnaire. In the second phase a two-arm controlled randomized clinical trial (RCT) will be conducted to assess the acceptance and efficacy of the application in improving parental knowledge, behaviour and self-reported practices/attitudes related to the oral health preventive measures. Clinically oral hygiene status and caries status of the participant children will be recorded too. The total appointment duration will also be measured.

Intervention:

Pilot study: After receiving the informed consent from the parents, the FU-APP digital application was shown to the parents attending the Department of Preventive and Pediatric Dentistry at the University of Greifswald for an oral health check-up on a tablet-PC. Once the parents have gained the experience of using the application and viewing the content, they were asked to fill out a user-acceptability questionnaire.

RCT: After receiving the informed consent from the parents, the child was seated on the dental chair for a normal check-up and the parents received the intervention according to the assigned arm in the form of information delivered. The information was based on the oral hygiene recommendations that followed the current German guidelines (counselling in diet, brushing instructions, and fluoride varnish application, nutrition and behavioural habits) according to the age of the child (Bundeszahnärztekammer 2020). Subsequently, parents in the test arm received additional information with the help of the web-based application (FU-APP) on a tablet-PC. Once the parents gained the experience of using the application and viewing the content, they were asked to fill out a knowledge-testing questionnaire in order to compare the knowledge at a follow up appointment. Parents in the control group also were asked to fill out the Questionnaire. Clinically oral hygiene status and caries status of the participant child were also recorded. For both arms, the follow-up visits took place 2 to 4 weeks and 3 months later and consisted of the same sequence of steps for the given intervention with modified questions included in the questionnaire to compare the improvement in oral health knowledge and the clinical records were recorded again to assess the improvement levels in the oral hygiene status.

Hypothesis:

The acceptance, usability and parental perception of a digital application (FU-APP) developed to promote evidence based oral hygiene knowledge among parents of young children to control ECC is positive and there is an additional positive effect in improving parental knowledge, behavior and self-reported practices/attitudes related to the oral health preventive measures while testing the efficacy of the FU-APP.

Application development:

An account is made on a certified online web-development platform and an application is developed on it. It will provide information related to oral health care for the parents of children between 6 to 72 months of age. FU application will be a web based application using guidelines and recommendations provided by the current German "Ratgeber 2020".

Sample size calculation:

Pilot study: Purposive sample including N = 20 parents of medically fit children aged between 6 months to 72 months.

RCT: The sample size was calculated assuming a difference of 0,5 between groups at follow-ups, setting α=5% and power (1-ß)=0.80 resulting in 28 children for every group. Adding an expected drop-out of 15%, a total sample size of 33 in every group (test and control) is needed.

Randomisation and allocation concealment:

Participants will be randomised through a computer-generated random-number list with allocation concealment to 1 of the 2 arms. Proper allocation concealment will be assured by a second investigator (RS), different to the investigator in charge of participants recruiting (JH). This investigator will have no possibility of knowing, which participant will go in which group avoiding influence on the randomisation.

Statistical analysis:

Part 1 - Pilot Data was primarily recorded on a spreadsheet Microsoft Excel (2017), then analysed using SPSS version 27. Spearman's correlation coefficient was applied to assess the strength of association between overall satisfaction and usage, acceptance, content and usefulness of the FU-App. Kruskal-Wallis analysis of variance and the non-parametric Mann-Whitney U test were applied to assess differences between FU category and overall satisfaction. P-value≤0.05 was taken as statistically significant.

Part 2 - Normality was checked for quantitative variables. Comparisons between the test and control were done using independent samples t-test, or Mann-Whitney U test for quantitative variables (according to the variable normality), while comparisons of qualitative variables were done using chi-square and Fisher exact tests, with Monte Carlo correction whenever indicated. Comparing the baseline and follow-up in each group was done using Wilcoxon signed rank and Mc-Nemar tests. Significance was inferred at p value <0.05. Data were analysed using IBM-SPSS for Windows (v. 23.0).

Quality assurance information:

Quality Assurance consisted of multiple steps in order to maintain a standard protocol during the study. As a first step, standard guidelines were set up for the data collection process through consensus by FU-Team. Secondly a detailed recruitment plan was developed to strategize and be aligned on the recruitment and data collection. Lastly the final step was to monitor and evaluate the process in the study field during the data collection and along with it identify the areas of improvement to strengthen the study further.

Standard procedures were used to ensure accurate and consistent measurements throughout the study. Standardized training was done in order to be familiar with the navigation of the FU-APP. Principal investigator (JH) was trained to conduct recruitment, measurement, and data collection for the RCT. The Principal investigator (JH) participated in a Quality Assurance (QA) training before starting the recruitment process. The training reviewed all data collection components and consisted of standardized measurements to minimize error. The training held before the follow-up sessions also included a mock data collection session.

The collected data information and documents were stored securely in the cabinets at the University Department. The consent forms and questionaries were filed properly in a customized folder designed and allocated to each recruited study participant. At the follow up appointment further documents were filed in the same individualized folder ensuring that each study participant had a customized protected folder and all quality assurance protocols are met. Only the principal investigator and study supervisors had the access to study participant's customized folders. Each study participant also received a copy of consent form and the confirmation form of willingness to participate in the study.

Inclusion Criteria:

• Parents can fully understand German language.
• Parents of medically fit children aged 6 months - 72 months.
• Parents/children who attend the Department of preventive and Pediatric Dentistry of the University of Greifswald for an oral health check-up.
• Willingness to participate in the study.

Exclusion Criteria:

• Parents who visit the Department of preventive and Pediatric Dentistry of the University of Greifswald for an emergency treatment or pain.
• Parents who decline to participate in the study.