2. Use a properly sized, quality canine toothbrush.
This can be tricky, since the Maltese breed is so tiny. Some larger adults (6 or 7 lbs.) may do well with a brush sized for toy breed dogs.
So another option is to use a finger-toothbrush. This is a small rubber piece that slips over your pointer finger, often allowing an easier way to scrub.
You will want to brush your Maltese's teeth on a regular basis. The more you do this, the more accustomed your dog will become to it. Ideally, you'll want to have a daily 3 to 5 minute session.
If your Maltese shows an intolerance to having his teeth brushed, start slowly. Choose the same time each day to handle him. Find a quiet spot without disturbances. For the first week or two, just hold him in your lap and gently run a finger over his teeth.
The next week, add a dollop of your chosen toothpaste, still using your finger. After another week, you should be able to graduate to the finger-brush or a small toothbrush.