Your veterinarian will want to do a full and thorough examination of your dog’s mouth. Depending on how cooperative your dog is, she may be able to look at him while he is awake. If not due to reluctance or pain, she may want to sedate him in order to give her a proper look. This will allow the vet to look at and under his tongue, throughout his gums and under his lips. Most dogs do not allow this while awake, especially if the mouth is painful, hence the sedation.
She will continue by performing a full physical exam on your dog. She will take special care to palpate his mandibular lymph nodes to check for enlargement. While the issue may be exclusive to his mouth and throat, the full exam will allow her to check over your dog entirely for other subtle symptoms he may be experiencing.
If there is a mass or abnormality in the mouth, your veterinarian may recommend taking a sample for biopsy. This will be able to determine if the mass is malignant or benign. She will also look for sources of trauma or some sort of foreign object that could have caused his condition such as a grass spur lodged in his cheek mucosa which lead to the development of an abscess.
General blood work may also be recommended to evaluate your dog’s blood production and general internal health. A complete blood cell count can indicate if your dog is experiencing any type of infection or anemia. The chemistry panel will give levels of the internal organs such as the liver and kidney enzymes. Blood work gives a good look at your dog’s overall health which is helpful for your veterinarian.