My dog has a gum growth. Is it serious or will it disappear on its own?

Masses within the mouth, much like other parts of the body, have the potential to be troublesome or of little consequence. Typically, the older the animal the more likely we are looking at something concerning. The most common benign finding often found within the mouth on the gumlines are epulis, which is simply a benign gum tumor. In some instances they require removal in order to facilitate food consumption or provide generalized comfort, but in many cases particularly when they are not growing in size, they can be left alone and can even spontaneously resolve. In other instances, masses in the mouth can be malignant and show up in the form of melanomas or squamous cell carcinomas. If this is the case, complete removal of the mass and the surrounding tissue is always recommended, followed by potentially other ancillary treatments. The only way to know for sure however would be with cytology or removal / biopsy. At six years of age, there is a pretty good chance Phoenix would likely benefit from a dental cleaning and x-rays regardless of the presence of this mass. If placed under anesthesia for this procedure, you can talk with your veterinarian about how you'd like to proceeded regarding potentially removing / biopsying the area. Hope this makes sense.