My dentist says I need a root canal on my left incisor before beginning Invisalign treatment. I was concerned about needing a crown on a front tooth that would turn yellow or dark around my gums. But my dentist explained that she does not need to place a crown after the root canal; she will fill it instead. I wonder if the tooth will break because it is weak after the root canal treatment. And with Invisalign repositioning my teeth, isn’t it just a matter of time before the tooth breaks? Thanks. Jamison from NY
Thank you for your question, Jamison. Although Dr. Brooksher would need to examine your tooth for an accurate diagnosis, we will offer some basic information about root canals and orthodontic treatment.
Does Root Canal Treatment Weaken Teeth?
Teeth that require root canal treatment are already weak from decay, trauma, or extensive fillings. And root canal treatment can weaken them. But whether a dentist places a crown on the tooth depends on the tooth’s condition and position.
- Back teeth – Back teeth must withstand the forces of chewing and grinding food. So, dentists protect the teeth with crowns after root canal treatment.
- Front teeth – Fewer forces affect front teeth. It is unlikely for an incisor to split vertically, but sometimes it can break horizontally. But preparing an incisor for a dental crown can weaken the tooth near the base before its roots. If you have lost most of your tooth structure or the tooth is already cracked. A dentist can reinforce your tooth with a flexible post and fill the tooth with a dental composite. Removing root canal filler material will prevent your tooth from turning dark.
Will Invisalign Break Your Root Canal Tooth?

Invisalign
Your dentist will begin Invisalign treatment when your root canal tooth is stable to prevent any trauma during treatment. Healing time can take one to two months, but each patient’s case is different, so your dentist will explain what you can expect. Also, Invisalign and other alternatives for clear braces move teeth with precision and gently apply force on your teeth.
If you are hesitant about your dentist’s treatment recommendation, ask questions to ensure you understand them. And you can consider getting a second opinion.
Baton Rouge accredited cosmetic dentist and Fellow of implant dentistry Dr. Steven Brooksher sponsors this post. Read about his efforts to offer some of the best dental care in Baton Rouge.