Study design

This prospective, controlled, randomized study aims to evaluate the impact of an enhanced personal dental program on OH and DH in cleft patients at the Nantes Cleft Centre using DMF and Silness and Loe index. Data will be collected through practitioner observation, using the subject’s medical records and questionnaires.

Setting of the study

Recruitment will take place at the Nantes Hospital, in the Maxillofacial and Dental Department and its tertiary cleft center. Each enrolled patient will be randomly assigned to the control group or test group. The allocation process is generated by the investigator after consent and clinical examination thanks to an algorithm on the eCRF. The allocation is revealed by the computer once the clinical examination is done. The framework of this trial is superiority.

For the control group, patients and their parents will be given the usual basics OH instructions by the maxillofacial surgeons or the orthodontists during the yearly follow-up. If dental care is needed, patients will be encouraged to contact their own dentist.

Patients in the test group will have a 30–45 min dental consultation added to the annual follow-up visit, during which OH and dietary instructions will be given, dental prophylaxis will be provided, and a professional fluoride treatment will be applied. If necessary, dental care will be provided during the same appointment or will be scheduled at the Nantes Hospital Pediatric Dentistry Department. In addition, patients will be contacted by telemedicine every 2 months to reinforce motivation, and an additional dental appointment will be made at 6 months for dental prophylaxis, application of professional fluoride treatment, and caries treatment. A summary of these different stages is provided in Fig. 1. Dental treatment will be carried out in the Maxillofacial and Dental Department; if necessary, equimolar mixture of oxygen and nitrous oxide (ENOMO) or general anesthesia (OR) will be available, depending on the patient’s level of cooperation.

Fig. 1

Patients in both groups will be scored for caries on day 1, year 1, and 1 year after the end of the study. All dental treatment and assessment of OH levels (DMF index and gingival index [27,28,29]) or carious lesion management for the test group will be performed by 2 dentists. The DMF index is the sum of the decayed teeth, field teeth, and missing teeth based divided by the total number of teeth for permanent and temporary teeth. Prior to the study, the two dentists will be trained in the assessment of OH (DMF index and gingival index) in order to calibrate the assessment method. Intra- and interrater reliability will be determined by weighted kappa scores using a random sample of oral photographs and radiographs from the series.

Objectives and criteria of judgment

The primary objective of this study is to assess the impact of an enhanced dental program with close follow-up of cleft patients on their OH status. The primary outcome is the evolution of the decayed, missing, filled teeth index (DMFT/DMFT) for both temporary and permanent teeth. It will be measured at 1 year.

Secondary objectives are to assess:

The impact of the enhanced dental program on the gingival status of cleft patients

The preferential localization of caries

The influence of orthodontic appliances, syndromes, and other cleft-related conditions such as malocclusion, oral-nasal fistulas, dental anomalies, sweet drugs, or drugs causing hyposialia on caries

THE influence of family dietary and hygiene habits on OH and its evolution during follow-up

The satisfaction of patients and their parents with the dental care provided

The accessibility (geographic and appointment availability) of dental care for cleft patients

The financial implications of this protocol

The evaluation criteria will be based on data collected during the clinical examination, such as the DMF index and Silness and Loe’s index, and on medical records. Parents and patients will also be asked to complete a questionnaire to assess their satisfaction. Finally, the financial impact of this study will be assessed through a comparative analysis of costs and benefits.

Patient recruitment-participants

Patients will be recruited by the primary investigator at their annual follow-up visit according to the following inclusion criteria:

Age between 3 and 15 years

Patients with syndromic or non-syndromic cleft lip and/or palate treated at the Department of Maxillofacial Surgery, Nantes University Hospital

Translation assistance for non-French speakers

The exclusion criteria are:

Patients without health insurance

Not registered with the French social security system

Refusal to participate in the study

Each patient attending their annual follow-up appointment with their maxillofacial surgeon will be offered the opportunity to participate in the study. If the patient meets all the inclusion criteria, the dentist will ask the child and his/her parents or legal guardian if he/she wishes to participate in the study. Clear and appropriate verbal and written information about the study (objectives, scientific interest, and practical procedures) is given. The dentist obtains the patient’s verbal consent (and that of at least one parent or legal guardian) without delay. The lack of delay is due to the design of the study, which has been approved by an ethic Committee for the Protection of Persons (CPP). Enrolment will start immediately after oral consent.

The number of subjects required has been calculated using two studies with the same primary outcome [17, 20]. It was fifty-four patients for the whole study, i.e., twenty-seven patients in the test and control groups. The 1st article used was by Ahluwalia et al.: with the results of Table 1 and the data from DFM index 2.38 ± 0.28 vs 0.62 ± 0.17, the number of patients required would be 54 (27 per arm). The 2nd paper was by Hazza’a et al.: with DFMT data 4.28 ± 4.19 vs. 1.66 ± 1.44, the number of patients required would also be 54 (27 per arm).

It seems relevant to consider a 10% loss of follow-up in each arm and therefore adjust the number of patients to be included in the study: we will end up with thirty patients per arm, i.e., sixty patients in total (27 × 1.10 = 29.7).

Consent for participation

At enrolment, patients and their parents or legal guardians will receive an information leaflet for their age group. The investigator will record in the patient’s medical record that the patient and parents have been verbally informed, have received the information leaflet, and have given verbal consent to participate in the research. At least one parent of all children, regardless of the age of the child, must be informed and consent.

Calendar  

Control group

Test group

D0

Annual surgical follow-up and orthodontics appointments

Referred to the dentist if needed

Dental check-up:

- DMFT/dmft

- Gingival index

Dental consultation:

DMFT/dmft

Gingival index

Verbal and written explanation for OH and its importance, appropriate brushing technic is taught, and fluoride toothpaste dispensed

Dietetic recommendations

Tooth scaling

Dental treatment if needed

Fluoride coating

M 2- M 4- M 8- M 10

-

Telehealth:

Answering patient or parents’ questions

Questions about the frequency and supervision of toothbrushing

Reminder about OH and dietetic recommendations

M6

-

Dental consultation:

DMFT/dmft

Gingival index

Verbal and written explanation for OH and its importance, appropriate brushing technic is taught, and fluoride toothpaste dispensed

Dietetic recommendations

Tooth scaling

Dental treatment if needed

Fluoride varnish

Y 1

Annual surgical follow-up and orthodontics appointments

Referred to the dentist

Dental check-up:

- DMFT/dmft

- Gingival index

Dental consultation:

DMFT/dmft

Gingival index

Verbal and written explanation for OH and its importance, appropriate brushing technic is taught, and fluoride toothpaste dispensed

Dietetic recommendations

Tooth scaling

Dental treatment if needed

Fluoride varnish

Satisfaction questionnaire for patients and parents about the dental program and the impact on their habits

1 Y after end of study

Annual surgical follow-up and orthodontics appointments

Referred to the dentist

Dental check-up:

- DMFT/dmft

- Gingival index

Annual surgical follow-up and orthodontics appointments

Explanation for OH and its importance

Referred to the dentist

Dental check-up:

DMFT/dmft

Gingival index

Variables and data measurement

Data for the analysis will be collected by the dentist during patient enrolment thanks to an electronic case report form (eCRF) on a secured website; all data will be entered electronically. This may be done at a core coordinating center or at the participating site where the data originated. Original study forms will be entered and kept on file at the participating site. Only authorized personnel can have access to the data. Data integrity will be enforced through a variety of mechanisms. Referential data rules, valid values, range checks, and consistency checks against data already stored in the database will be supported. Additional errors will be detected by programs designed to detect missing data or specific errors in the data. These errors will be summarized along with detailed descriptions for each specific problem in data query reports. The rest of the data collection for the test group will take place during the dentist’s appointment for both the primary and secondary objectives. Data will be collected for both groups on day 1, year 1, and 1 year after the end of the study. For the test group, additional data will be collected at 2, 4, 6, 8, and 10 months.

The data monitoring committee is a part of the clinical research department of Nantes’s Hospital; it is a structure dedicated to applied human research (clinical research); it is independent from the sponsor and competing interests. It monitors trial conduct and safety, assesses risks and benefits, and makes recommendations to protect the participants of clinical trials. All study-related information will be stored securely at the study site. All participant information will be stored in locked file cabinets in areas with limited access.

The primary investigator will have access to the final trial dataset.

Statical analysis

At the end of the study, before the statistical analysis, a data review will take place with the principal investigator, the project manager, the data manager, and anyone closely involved in the study. The aim is to have an overview of the conduct of the study, the problems encountered, and any deviations from the protocol.

A description of the data will be carried out; the quantitative variables will be described by the mean, the standard deviation, and the 1st, 2nd, and 3rd quartiles. The qualitative variables will be described by their respective numbers and percentages.

The analysis of the primary endpoint, the comparison of the difference in progression between enrolment and 2 years for each patient between the two groups, will be examined using Student’s t-test. A sensitivity analysis adjusted for known confounders may be performed by linear regression. An additional sensitivity analysis is performed by comparing the values at enrolment with the values at 6 months and 1 year.

Missing data will be treated with multiple amputation, and non-adherence to the protocol will be treated in intention to treat.

Data monitoring

Through our web-based electronic case report form, the data coordinating center has daily visual cross-validation of the data for complex errors and regular on-site monitoring; the quality and completeness of the data will be reflective of the state of the art in clinical trials. The monitors will review the source documents as needed, to determine whether the data reported in the web-based system are complete and accurate.

Ethics statement

This non-interventional study has been declared to the French Data Protection Authority (CNIL) and received a favorable opinion from the French National Committee for the Protection of Individuals. It has also been registered at ClinicalTrials.gov (NCT05867862).