A man was left with a circle-shaped wound on the roof of his mouth after performing too much oral sex, dentists said.

The 47-year-old paid a visit to his dentist after noticing a filling in his tooth was cracked.

While dentists were examining his mouth they noticed a “circular-shaped lesion” on his soft palate — the roof of his mouth.

The man, from Mexico, was unaware of the lesion and said it had not caused him pain.

Confused as to what it might be, dentists took a full history of the patient.

He told dentists he had a history of marijuana and cocaine use and was sexually active with men.

The last time he had performed oral sex on someone was three days before his appointment, according to the BMJ case report.

Dentists concluded the lesion, known as an erythema, was caused by him giving oral sex.

“The contact of the palate with the penile glands may cause a hematoma due to blunt trauma and dilatation of the blood vessels because of the negative pressure created while sucking,” Dr. Luis Alberto Mendez, who treated the patient, wrote in the report.

“With this information, we concluded that the erythema on the soft palate was associated with the practice of oral sex.”

The lesions went away on their own, although he was advised that oral sex was off the cards for a few days.

After 15 days the lesions had completely gone and the man was able to resume his sex life.

It’s not the first time this type of injury has been recorded, although it is rare.

A study of 132 sex workers in Peru noted that 17 of the participants suffered lesions in the mouth due to oral sex, the report notes.

“It is pertinent to consider this practice [oral sex] as a potential cause of oral lesions, particularly on the palate,” Mendez added.

“It is important to obtain a comprehensive history and a detailed oral examination.

“In high-risk patients, we should consider the possibility of sexually transmitted disease.

“As health care professionals, it is our responsibility to provide counseling and reassurance to all patients presenting with these lesions, particularly those undertaking high-risk sexual behavior.”