top of page

“Proving The Groove”


dentist showing x-rays on the tablet

Q: My husband and I are the parents of four children. Three weeks ago, our youngest daughter, age 25, saw a new dentist. She has always had perfect teeth. She finished university two years ago and is working.

On her recent visit, she mentioned that she had not seen the dentist since her third year of university over three years ago. She has no insurance so we said make an appointment and get your teeth cleaned. When she visited the dentist, he took many x-rays and did a thorough exam. When her x-rays came up, the dentist was surprised. He said it looked like she had massive decay. Our daughter was stunned. She’s been a good flosser and brushes twice a day. The only thing she didn’t like about her teeth was the dark grooves in her molars. The dentist said that he’d never seen anything like this. He said the clinical exam could not have detected the problems the x-rays revealed.

She needs two root canals and five crowns. How can this be? He said that small fillings placed at the right time would have prevented this. We’re blown away by the extent of the problem and of course the cost. Have you ever heard of this before? We need to understand.



A:Over fifteen years ago a research team investigated stained grooves in molar and bicuspid teeth. They discovered a 100% correlation between dark stain and decay in non-smokers. In other words, if you were a non-smoker and displayed dark stain in your molars there would be decay under that stain. With smokers, the decay rate went to 65%.

Since that time, devices more sensitive than x-rays have been developed to discover decay in molars in its earliest stage. In my office, we discuss this problem with parents of children and if we find dark stain we encourage a procedure we call “proving the groove”. In this procedure, a dental drill tip smaller than the tip of a fine point ball point pen, is used to trace the deep grooves of the teeth. Most of the time “freezing” is not needed. The stain and any initial decay may be removed and then closed with a special technique that sterilizes the tooth and prepares it for a “micro” filling.

Yesterday I saw a young adult (non-smoker). I investigated three teeth. Of the three, two teeth had a small amount of decay but the third had decay that extended to the nerve. If we had not “proved” the groove on that tooth she would have ended up with a root canal and crown. Remember “a stitch in time saves nine”.



If we can help, we’d like to. Call 778-410-2080 for a consultation or visit us today.

Based on actual patient cases

 Calvin Ross Crapo

Ask The Dentist

Dr. Crapo gives his readers free dental advice.

Blog Entries

Read more on various topics relating to dental and oral health.

bottom of page