Motivational interviewing in general dental practice: A review of the evidence.

This is probably the best systematic review we have of motivational interviewing in dentistry and oral health at this time. If you don’t want to read the whole study, I think the last line in the abstract says a lot:

Training in motivational interviewing for dental personnel could be a very useful addition to the skill set of practitioners and dental teams.

https://www.ncbi.nlm.nih.gov/pubmed/27982007