UT Southwestern dental implant study to test bite force, muscle efficiency in lower dentures

Dr. Ron Caloss (left), measures Sharon Lewis' bite force and jaw strength.

DALLAS — July 6, 2006 —  A childhood bicycling accident left Sharon Lewis with a seriously injured jaw and face, and for years her jaw muscles weakened and the condition of her teeth deteriorated.

Mrs. Lewis' dentist had to replace the Waxahachie resident's upper teeth with dentures when she was in her early 40s. And about two years ago, Mrs. Lewis' lower teeth also started troubling her, and they too had to be replaced with dentures.

The dentures in her lower jaw, however, never felt right.

"I was miserable and in pain all the time," said Mrs. Lewis.

After reading about the need for patients for a dental implant study at UT Southwestern Medical Center, Mrs. Lewis sought the expertise of Dr. Ron Caloss, assistant professor of oral and maxillofacial surgery.

"Denture wearers frequently come to our clinic complaining that their lower denture moves around whenever they eat and talk. Their quality of life can really be negatively impacted," said Dr. Caloss. "This only gets worse with time as the lower jaw will atrophy once their teeth are removed and no longer stimulate the bone. Dental implants can be used to stabilize an ill-fitting lower denture and dramatically improve the patient's ability to chew, talk and enjoy life."

A dental implant is a small screw made of a titanium alloy that is inserted into the jawbone. Over time, the bone integrates with the implant.  A bridge, a crown or denture is then attached to the implant, thus allowing the implant to supply the stability previously supplied by the roots of the tooth.

People who qualify for the implant study undergo outpatient surgery. After allowing several weeks for healing, the lower dentures are attached to the new implants. Periodic testing measures the jaw's maximum biting force and muscle efficiency.

Dr. Caloss and Dr. Gaylord Throckmorton, a professor in of cell biology, are currently conducting a study to evaluate whether lower-denture implants can improve biting force and masticatory muscle efficiency.

This will be the first study to correlate the changes in bite force with electromyographic (EMG) activity in the muscles of mastication and to assess muscle efficiency changes in patients with implant-supported overdentures.

Since surgery, Mrs. Lewis returns every three months to UT Southwestern so her bite force and jaw muscle strength can be measured and recorded.  She said undergoing dental surgery and participating in the study has been well worth the result.

"It's been a remarkable journey for me," Mrs. Lewis said. "I feel more confident, and I'm not in constant pain any more. This has improved my day-to-day living."

Participants are still needed for the study. To qualify, patients must be non-smokers and have existing upper and lower dentures in good repair that they have been using for at least six months. All eligible participants receive lower dental implants at no cost to them. For more information contact Elizabeth Muscatell at 214-648-3034.

Visit http://www.utsouthwestern.org/surgery to learn more about UT Southwestern’s clinical services in surgery.


Media Contact: Connie Piloto

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