Discoloration of primary incisors (front teeth) may be extrinsic or intrinsic. Extrinsic discoloration is stain that can be removed by the toothbrush or a professional cleaning. Intrinsic discoloration is usually caused by a blow to the tooth.
Some apple juices, grape juice and tea may stain the teeth. If the teeth are exposed to these liquids too often, the enamel may begin to break down. A flat appearance of the enamel is followed by white spots that can progress to decay. Juices should be limited to mealtime only.
Bacteria, known as chromogenic bacteria, leave a dark brownish black stain on the primary teeth near the gum line. We do not know the cause of this problem and this stain cannot be removed with a toothbrush. A professional cleaning is usually necessary to remove this type of stain. Toothpaste flavored with xylitol instead of sorbitol may be helpful.
Intrinsic discoloration cannot be removed by cleaning the teeth. If the enamel layer did not form properly, the teeth may be pitted or discolored. These teeth are usually more susceptible to decay.
Intrinsic Discoloration due to Trauma
A blow to an incisor, or a concussion injury, may result in intrinsic discoloration. This discoloration may range from variations in shade of grey or brown. The blood vessels inside the tooth in the pulp chamber break and the blood is absorbed into the tiny tubes (dentinal tubules) that travel from the pulp chamber to the enamel. Enamel is translucent, so the blood pigments in the tubules reflect through the enamel. This may resolve without any treatment, but should be evaluated. If an abscess is considered a possibility, a painless procedure to remove the dead tissue from inside the tooth may be recommended. The discoloration will not be reversed by the procedure, but there may be some improvement in the appearance. This is primarily an esthetic problem and more than 80% of discolored primary incisors exfoliate (fall out) without any intervention.
Extrinsic Discoloration due to Medications
Liquid and chewable medicines may contain large amounts of sugar and many are colored with dye. A yellow-brown film may cover the teeth, particularly the bottom front teeth. Bedtime brushing after the bedtime dose of medicine will minimize this problem.