“What are the lumps inside my mouth?”

tori

Many things can cause lumps inside the mouth, ranging from normal anatomy to dental infection to forms of cancer. I recommend you see your dentist or an Oral and Maxillofacial surgeon for an evaluation.

Consult your dentist.

The most common "bumps" I am questioned about occur on the boarder of the lower jaw on the inside. These are called "torus mandubularis" and are a fairly common variation of normal. It is not uncommon for a patient to have lived with these bumps for years and not noticed them until some event such as some trauma draws attention to them. Generally they are of no consequence.
On occasion, I have seem these boney protuberances become so large that they nearly touch in the middle of the mouth but they are usually much smaller. I personally have small to moderate sized ones that are the most bothersome when I have to have dental X-rays taken. Then they get bumped or abraded and are uncomfortable for awhile.
One time when I was in the service I had a young dental assistant who had tori (plural for torus) that nearly touched and there was barely room for the frenum (the little tissue band that holds the tongue to the floor of the mouth and inside of the front of the lower jaw) to pass through. She asked me to remove the bone and initially I declined as they really were not causing any problems that I could document. A few weeks later she came to me with tears in her eyes and she wrote on a piece of paper that she had a peanut stuck under the bumps that she could not get it out. I removed the peanut and she informed me that I was going to remove the tori. I did and she was greatly relived.
There is another type of torus that occurs on the roof of the mouth or hard palate. It is called a torus palatinus and is also harmless. These generally are not removed unless they interfere with the fit of a denture or other appliance that must fit over the palate. They vary in size but again are harmless.
Both the mandibular and palatal tori are cover by relatively thin soft tissue and are, therefore, fairly easy to abrade or rub if irritated. Because of this characteristic often when a denture must be placed over these areas the bone needs to be removed. Usually the bone growths does not recur after removal but form time to time they may at which point they must again be removed.
There is another type of boney bump that can occur on the outside of the upper or lower jaw. For some reason these boney protuberances are call "exostoses" (exostosis, singular). They may actually appear as a boney ledge or ridge on the side of the jaw proper at or very near the crest of the gum tissue near the teeth. Again these can be removed if they present a problem. They may or may not recur after their removal.
I have made some vigorous assumptions related to the initial question and perhaps have jumped to some erroneous conclusions because of those assumptions. There are obviously other types of "bumps" that can occur in a patient's mouth.
There are soft tissue bumps and swellings that can be neoplastic (tumors both benign and malignant) and reactive (infections and irritations). These can occur virtually anywhere in the mouth. They can be firm or fluctuant (squishy). These need to be evaluated by a dentist or physician and diagnosed based upon their findings.

Lumps could be a lot of things. If they are coming from the bone, they are most likely toris or torus, which is just excessive normal bone tissue, considered normal bone. They need to be removed o my if they are on the way for dentures or having constant trauma while eating because of their size. If the lumps are in the floor of the mouth or any other soft tissue, they could be any mass or enlarged salivary gland. The best way to know if those lumps are normal or abnormal is visiting your local oral surgeon.

That would require a clinical evaluation. You need to contact a local oral surgeon and set up an appointment.

You should first see your dentist. Then if he cannot diagnose your lumps, see an oral surgeon.