‘Well it didn’t start hurting until you started messing with it!’
We get this as dental professionals a lot. And we understand. Let’s talk about why post-operative sensitivity can happen and why it (usually) isn’t something to worry about.
What Is Post-Operative Sensitivity?
A study in 2013 decided to determine what different types of variables contributed to post-operative sensitivity. In their article, they defined sensitivity to be ‘pain in a tooth associated with mastication or with sensitivity to hot, cold, and sweet stimuli that occurs 1 week or more after restoration¹.’
What Causes Post-Operative Sensitivity?
When a filling restoration is performed on a tooth, a surgery is being conducted. The tooth’s decay is being excavated using a high-speed handpiece (drill) that causes heat and friction to occur on the tooth. Many times, this causes an inflammation of the inner layer of the tooth (pulp) known as pulpitis. Often, this resolves without worry or further adjustment. Other forms of post-operative hypersensitivity are due to hyper-occlusion. When the tooth is filled back up, the filling may be too high. Biting on this filling that is too high is like hitting a bruise, and results in pain. Lastly, post-operative sensitivity because the filling material may have gaps in it, which could be due operator error. There’s always the chance the filling can go wrong during the procedure, resulting in a pulp exposure that would illicit pain – but this only occurs rarely and the dentist will tell you during the procedure if this had occurred, so no need to worry about that here.
In the study discussed earlier, 30% of the teeth that were treated for fillings had post-operative sensitivity, and 18% had the sensitivity last more than 4 weeks. The study also found that 10% of those who had the fillings did not have sensitivity before the filling¹.
Should I Be Worried?
You shouldn’t be worried if you exhibit sensitivity to cold/hot, sweets, or even clenching after you have had a filling. You aren’t alone when it comes to sensitivity, and studies show that the only significant factor for not having sensitivity is if you are an older individual (sorry, youngins). Other studies are inconclusive on whether or not the type of filling and size increases or decreases the chance for sensitivity. If sensitivity does arise, wait at least two weeks to see if the sensitivity lessens. A quick call to your dentist after may be necessary to adjust or redo the filling, if necessary.

To Summarize:
- Sensitivity after fillings is common
- Post-op pain could be from a variety of reasons, usually because the bite is too high
- You may be more sensitive after the procedure than before it
- You shouldn’t be worried about post-op sensitivity, though a quick visit back to your dentist might be necessary
References:
¹ Berkowitz, G., Spielman, H., Matthews, A., Vena, D., Craig, R., Curro, F., & Thompson, V. (2013). Postoperative hypersensitivity and its relationship to preparation variables in Class I resin-based composite restorations: findings from the practitioners engaged in applied research and learning (PEARL) Network. Part 1. Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995), 34(3), e44–e52.
Liability Statement:
The medical advice given in this blog should only be utilized by a medical professional who has received a medical degree. I am not responsible for the medical advice given in this blog and each case should be reviewed extensively with sources outside my blog. This blog is for education purposes only and is not meant as a substitute for an academic institution.