<s>[INST] Hello,I was fitted for a dental night guard due to bruxism. I have had it re-fitted several times. Since wearing it, there are times where I lock onto the occlusion and am unable to open my mouth in the morning. One dentist told me to stop wearing it as it could damage my jaw, another told me to continue wearing it. It happens about one in every four times i wear it. I have never had a muscle spasm when not using. I almost think unconsciously I am biting harder as I wake up very aware of the clenching and do not notice this when not wearing the nightguard.  Please advise, and thank you kindly for your time!Shanti Z [/INST] Thanks for your query, I have gone through your query. The limited mouth opening and pain could be because of the bruise and use of the splints leading to disc displacement in the Temporomandibular joint. If the splints are designed properly and if the thickness is too much and if it is hard splint. Consult an oral physician and get it diagnosed. You can stop using the splints for few days. You can take anti-inflammatory Chat Doctor.  Furthermore, you can also take muscle relaxants like chlorzoxazone. Furthermore, you can give hot fomentation over the joints. Do not eat hard things, do not open your mouth too wide. Take soft diet. I hope my answer will help you, take care. </s>