Rare but Harmless Jaw Anomaly Can Be Misdiagnosed as Serious Condition

BUFFALO, N.Y. -- When dentists see an unusual shadowy area of bone loss on an X-ray of the lower jawbone, they may be concerned and order a biopsy.

In dental parlance, this strange formation may represent an "anterior variant of the mandibular lingual bone depression," a condition that may look serious, but actually is a harmless bone depression, a rare congenital anomaly that needs no further treatment.

"It's important to know that it's a benign developmental condition," said Lynn Solomon, D.D.S, first author on a paper discussing this "diagnostic challenge" in the September-October issue of General Dentistry.

"Some dentists order a CT scan or surgery when confronted with this unusual formation, but it can be diagnosed easily through an occlusal X-ray view, which is not used routinely," said Solomon, assistant professor in the Department of Oral Diagnostic Sciences in the University at Buffalo School of Dental Medicine.

"This type of X-ray requires a larger piece of film, and the beam of radiation is aimed from below the jaw. This anomaly was first reported in 1942, but a whole new generation of dentists comes along and people tend to forget things."

Only 47 clinical cases, including one Solomon describes, have been reported in the literature since then, according to the paper, and men are twice as likely as women to have the anomaly.

A CT scan exposes patients to unnecessary radiation and surgery is invasive and comes with risks, as well as unnecessary expense. Taking annual occlusal X-rays can confirm that there is no change in the depression over time, ruling out a serious condition, she noted.

"It does keep the cost of health care down when people use available tools instead of 'fancy' interventions."

Additional authors on the paper are Eugene A. Pantera, Jr., D.D.S., and Edward Monaco, D.D.S., from the Departments of Periodontics and Endodontics, and Restorative Dentistry, respectively; Stuart S. White, D.D.S., Ph.D., from the UCLA School of Dentistry, and Lakshmanan Suresh, BDS, MS, FDSRCPS an oral pathologist in private practice in Buffalo.