Table 1.

Inclusion and exclusion criteria.

Inclusion criteria	Exclusion criteria
i) This study limited the search to empirical studies (qualitative, quantitative and mixed methods). Qualitative studies included interviews, focus groups or surveys, and quantitative studies focused on clinical trials, cross-sectional studies, randomised controlled trials, non-randomised trials with or without control groups, cohort or case control studies and surveys.	i) Non-empirical works, systematic reviews, textbooks and theses were excluded from the study.
ii) Only primary data from the articles were included.	ii) People who affected by mental health disorders were not included. Also, people with SHCN who remain at home within a supportive living environment were excluded.
iii) This study focused on individuals with different types of disabilities such as physical, developmental, intellectual, autism spectrum disorder (ASD), hearing impaired and others.	iii) Individuals with visual impairment were excluded as well, as conventional teaching methods such as visual aids and disclosing agents are not useful for them to maintain oral hygiene. Alternative teaching aids such as an OHE booklet in Braille and audio narration of the booklet need to be used to educate them.
iv) Articles written in the English language from 1st January 2011 to 31st December 2020 have been included.	iv) Papers written in the languages other than English were excluded, as we did not have access to them, and studies published before 2011 were excluded as well.
	v) Hospital-based studies were excluded.