The objective of this study is to test a personalized oral hygiene instruction form (POHIF) elaborated after oral examination by a dentist and implemented by caregivers in nursing homes or similar medicalized homes.

The study aims to test whether a newly developed tool can help caregivers improve the oral health indices of institutionalized residents.

Caregivers of the institution will be identified by the medicalized home and will be asked to answer a questionnaire pertaining to various aspects of oral health care. The questionnaire is divided into 5 themes, the first section will collect general information on the caregiver and will comprise 3 questions about age range, years of professional experience and current position. The investigators will not be able to identify the caregivers out of the 3 questions. The second theme will request information on the knowledge and clinical practices related to the oral care of dependent and independent in-residents. Caregivers will also rate the perceived importance of oral care in relation to general health on a Visual Analogue Scale (VAS) from 0 to 100. Other questions will inquire about tooth brushing, intraoral inspection, cleaning of prosthetic appliances and storage habits. The third theme consists of a closed check-list of instruments, asking if they were known to the caregivers and if they used it in their institutional setting. The fourth theme covers the caregivers' perception of oral care and potential barriers to its provision. The fifth and last theme related to the perceived barriers concerning institution logistics and resident-related factors. At the end of the fifth section, an open question will be added for a qualitative description of any additional barriers to oral care that were not covered by the previous questions.

The questionnaire will be filled in a focus group should the sanitary situation related to the pandemic permits; if necessary, the questionnaire can be administered online as well. The questionnaire will comprise 20 questions and one open ended question, and takes an average of 6-8 minutes to be completed. All caregivers in a unit will receive a theoretical oral health provision training, followed by a hands-on session. After the training, the caregivers will be asked to fill the same questionnaire and the answers/ scores will be compared before and after the training.

Resident living in an institution will be screened and included if fitting the inclusion and exclusion criteria. 46 participants will be recruited. After recruitment, all participants will receive an oral examination and an oral hygiene kit. The oral examination will record plaque index (PI) by O'Leary, denture cleanliness index (DCI) by Ambjornsen and tongue coating index (TCI) by Shimizu.

The participants will also be asked to fill a questionnaire about their own perception of their oral health related Quality of Life (General oral health assessment index, GOHAI). The oral examination will be conducted in the resident's room.

The investigators will then customize the POHIF for all participants. After the completion of all the examination in all recruited participants, participants then will be randomized into two groups. The randomization will be done in clusters according to the geographic location of the resident room so that bundles of rooms will be in one group and another bundle of rooms will be in another group. Investigators will ensure that the residents in the different units are not all dependent on care or independent and that they are representative of the institution population.

This bloc randomization will insure that participants that are in the same room belong to the same group. Randomization sequences will be obtained from www.randomizer.org. The sequences will be kept in sealed opaque envelopes.

The investigator that will conduct the first examination and elaborates the POIF will be blinded to the participant group allocation.

For participants in the intervention group, the personalized oral instruction form will be handed to the independent residents along with a hygiene kit comprising the necessary tools to conduct oral hygiene by the second investigator (N.M). For dependent residents, the personalized oral instruction form will be handed to the caregivers along with the personalized oral hygiene kit.

In the control group, independent and dependent residents will receive a hygiene kit, independent resident will continue to conduct their own oral care as usual, and for dependent residents, caregivers will provide the oral care as usual.

The duration of the study will be 3 weeks from the day of provision of the oral hygiene kit and the start of the intervention for every cluster of participants.

After 3 weeks, all included residents will get a second oral examination by the same investigator who conducted the first one.

Oral health indices will be again recorded.

Inclusion Criteria:

• Living in an institution for more than 6 weeks
• Understand French
• Give written informed consent or consent can be obtained from their next of kin or legal representative if necessary

Exclusion Criteria:

• Non-cooperative participant
• Having an infectious disease (according to a medical report)
• Are undergoing currently dental treatment or need urgent treatment in next 3 weeks

Data will be made available upon reasonable request

The investigator conducting the oral examination was masked to the group allocation of the patient.