movie help needed

I too am looking for a movie in which a guy has a computer chip or something placed in his tooth by a dentist so that someone can control his memory. I remember he witnesses a murder and with this chip in his tooth he is trying to remember the details but is have trouble because of someone controling his thoughts with this chip.

Well, I went ot Google and typed 'movie "computer chip" teeth murder witness' and got some promising leads.... but no cigar

If I remeber correctly the guys wife or girlfriend was an artist who would paint picture while sitting on the beach and I believe the movie was made sometime in the 80's

I still need help finding this movie