My pup did not like to have her teeth brushed but I was tenacious. Now anytime anyone in the family goes to the dentist and they don't want the tooth brush the dentist always offered (because they use the electric toothbrushes) I have them get me that baby/child brushes. I push the tooth paste deep into the bristles, let her have a whiff of it and she gets so excited chewing in the bristles she kind of ends up brushing her own teeth.
Someone else on YT clued me into this method.
Then I top it off with a bit of manual brushing from me that she is fine with tolerating at that point.
Got to watchmthat they don't eat the bristles, but mine does not chew that hard. The brushes do not last long though, so the family and dentist keep me supplied for free