When it comes to tactile issues, we don't typically think of the skin inside our mouths, but the truth is that sensory processing differences often cause kids to be oversensitive or under-sensitive in their mouths. Toothbrushing for kids with sensory issues can be very difficult as a result, but there are strategies for making it easier.
First, as with all sensory issues, desensitization can help prepare the child with sensory issues for unfamiliar and unpleasant sensations, so before toothbrushing, you can have your child gently massage her face around her mouth. A handheld vibrator or even a vibrating toothbrush (with the bristle side away from her skin) might help her handle brushing afterward--and a vibrating toothbrush might feel more comfortable to her than a regular toothbrush.
Have your child rinse his mouth after eating and before brushing, especially after eating acidic foods, since toothbrushing immediately afterward isn't good for tooth enamel. You might also have him try tooth pulling with coconut oil, swishing it in his mouth and spitting it out in the garbage afterward (not the sink—it can clog it). According to Ayurvedic medicine, this can reduce bacteria growth. Swishing water or coconut oil in the mouth may be desensitizing enough for your child to be able to handle toothbrushing.
Choose the right toothbrush. Kids can be much more comfortable with a brush they find friendly, perhaps because of the color or the cartoon image on it. Choose a soft head, and when you see the dentist, make sure your child is brushing properly (and if you're doing it for them, make sure you're not missing any spots or brushing too hard). My son with sensory issues prefers three-headed brushes. You may have to try several different types of brushes to find one that will work for your child.
Make brushing fun. Have your child see if she can guess when the two-minute timer goes off and brush for exactly two minutes. For a younger child, sing a two-minute-long song while she brushes, or play a recorded one for her.
The trouble with toothpaste can be the taste or the texture. Try non-mint toothpaste flavors and nonfoaming toothpastes. For example, Orajel toddler training toothpaste doesn't foam, and Tom's of Maine, Burt's Bees, and Tasty Paste makes toothpaste in flavors from strawberry to chocolate.
Talk to your dentist about the use of fluoride on your child's teeth. If your child won't use toothpaste much less a toothpaste with fluoride, you have other options such as fluoride rinses. (If your child uses these, make sure he doesn't swallow and that he doesn't drink water right after using it.) A dentist can coat teeth with fluoride to prevent cavities.
Teach your child how to floss and consider using a high-speed flossing machine such as a Water-Pik. You might be surprised at what your child will tolerate when it comes to sensations in the mouth. Ask your child to describe how a sensation feels and whether it's pleasant, unpleasant, or "in between" (neutral) and why. Could the sensation be adjusted? Could it involve more or less pressure? A different kind of dental floss?
Be flexible about where your child brushes her teeth. Standing on a stool in front of the bathroom sink, where she might feel insecure because she isn't on solid ground, might make her anxious. Bathrooms can be echoey, too. Don't run the faucet while toothbrushing—it wastes water and can create an unpleasant sound as it hits the porcelain. Brushing at the kitchen sink or in a less echo-y bathroom might feel more comfortable for your little one.
Let your child choose the water temperature when brushing.
Consider taking your child to a pediatric dentist who will take extra time with your wary child and thoroughly explain procedures beforehand. Many regular dentists use strategies pediatric dentists do, such as offering the child sunglasses to block the strong exam room light and a lead x-ray bib for comforting deep pressure against the skin even when x-rays aren't being taken. Keep in mind that it might take extra time and practice for your child to master brushing and flossing. Three cleanings a year rather than two might be best.
If you don't have dental insurance through a job, consider buying it privately or buying a dental discount card. Talk to your dentist about your options for keeping your costs down as you support your child in maintaining good oral hygiene and healthy teeth and gums.
For more practical tips for everyday challenges, check out the award-winning Raising a Sensory Smart Child: The Definitive Handbook for Helping Your Child with Sensory Processing Issues by Lindsey Biel, MA, OTR/L, and Nancy Peske.