It is normal for teeth that have recently received dental treatment to be slightly sensitive. Sensitivity may result from eating or drinking hot and cold things. Pain may also occur when pressure is applied to the tooth when chewing. There are a few different things that may be leading to this type of sensitivity.
The tooth may be slightly traumatized. When a filling is performed, it can be slightly irritating or traumatic to the nerve or pulp of the tooth. This can cause inflammation of the nerve leading to sensitivity in the tooth. This type of sensitivity is normal and usually subsides within 2 weeks.
The bite may be high. When you have a filling placed, the tooth is numb so it is often hard for the patient to tell if the bite is correct. If the bite is not balanced properly, it can focus too much biting force on one tooth, causing sensitivity. A slight adjustment will usually correct this.
Another cavity nearby. If you have multiple unfinished fillings or active periodontal disease in the area it is not always easy to tell which area is causing the sensitivity. This is because all the teeth are linked by branches of the same nerve. So it can be hard to tell which tooth it is. As a result, you may be feeling pain on one tooth, but it may be caused by a cavity or problem in another tooth.