Dental implants seen as best replacement for old bridges

Dental implants seen as best replacement for old bridges

June 10, 2008 -- According to the American Academy of Implant Dentistry (AAID), aging dental bridges are difficult to floss, often decay, and require replacement with longer bridges. The AAID recommends replacing them with permanent dental implants.

"Many of us have had the same bridges in our mouths for 20 years or more. They were put in at a time when bridgework was considered to be the norm for replacing missing or compromised teeth," said Olivia Palmer, D.M.D., of Charleston, SC, an associate fellow of AAID and diplomate of the American Board of Oral Implantology.

Palmer explained that bridges generally fail after five to 10 years because patients have trouble flossing them. "Because these bridges link missing tooth spaces to adjacent teeth, many patients find it very difficult to floss the bridge," she said. "Therefore, root surfaces below and around bridgework often decay, if not kept meticulously clean by flossing. It is impossible to repair this marginal decay, so the entire bridge must be replaced."

For most patients, implants are a better treatment alternative because they preserve the bone of the jaw, can be flossed easily, do not decay, and function just like natural teeth, she added. Today, highly precise computer-guided dental implant surgery has made the procedure faster, highly predicable, long-lasting, and 97% successful.

Palmer advises anyone with one or more missing teeth who might consider having a first bridge inserted or replacing an old one to weigh the benefits of implants before getting treatment.

Lantis Laser's OCT system moves closer to commercialization

Lantis Laser's OCT system moves closer to commercialization

June 10, 2008 -- Lantis Laser has commenced the final development phase of its optical coherence tomography (OCT) Dental Imaging System.

The OCT Dental Imaging System consists of a small, handheld scanner that uses coherent light to capture hard or soft dental tissue in high-resolution cross-sectional images with up to 10 times the resolution of an x-ray. It can be used for early detection of tooth decay, caries around restorations at an early stage, gum disease, and more.

"The components of the OCT system that needed to be upgraded to meet the requirements of the fast scanning speed enabled by Axsun Technologies' swept source laser are being readied for integration into the OCT beta systems," said Stan Baron, president and CEO of Lantis in a company press release.

In April, Lantis announced a partnership with Axsun Technologies to develop its integrated microelectromechanical systems (MEMs) OCT engines.

The final developmental phase, the last stage before commercial rollout, also involves the design of the OCT system's mobile cart, to be undertaken by Eclipse Product Development.

"We expect to deploy the beta systems for clinical use in the July/August time frame," Baron said. A full commercial rollout is expected in 2009, with a targeted retail price of around $25,000.

Studies show less need for nerve blocks

Studies show less need for nerve blocks

June 10, 2008 -- Numb lips, a bitten cheek, slurred words. For years dentists haven't had much choice about causing such temporary discomforts with a nerve block in patients needing mandibular procedures. But recent research suggests an infiltration will suffice for most restorations.

Infiltrations, which target only the nerves of a specific tooth, work just fine in the maxilla. By contrast, the thick bone in the mandible keeps the anesthetic from getting to its target. So the standard recommendation is to use inferior alveolar nerve block (IANB) for any procedures done on the mandible -- much to the distress of many patients. "The thing that makes the patient fearful is that big injection," says Paul A. Moore, D.M.D., Ph.D., M.P.H., chair of dental anesthesiology at the University of Pittsburgh.

In addition to causing less numbness, using infiltration reduces the risk of adverse events associated with IANB, such as trismus, nonsurgical paresthesia, and hemorrhage in hemophiliacs. It's also simpler to master than some of the other alternatives to IANB, such as intraosseous and intraligamentary injections.

The new hope for mandibular infiltrations comes from experiments with articaine, a relatively new local anesthetic that has beaten lidocaine in recent comparative trials. In fact, at the International Association of Dental Research meeting in Toronto in July, Dr. Moore (previously paid as a research consultant for articaine-maker Septodont and other dental supply companies) will present data from a study showing that articaine is more effective than various formulations of lidocaine, prilocaine, mepivacaine, and bupivacaine.

In April 2006, researchers from the University of Newcastle upon Tyne (Journal of Endodontics, April 2006, Vol. 32:4, pp. 296-298) reported some of the first success anesthetizing lower teeth with an articaine infiltration. They were able to numb about 65% of mandibular first molars with articaine, compared to only 39% with lidocaine.

But the study left open the question of how these rates might compare in a matched group of patients getting IANB. Now the same group has reported on such a trial, in the May 2008 Journal of Endodontics (Vol. 34:5, pp. 514-518).

The researchers administered IANB using a solution of 2% lidocaine (1:80,000 epinephrine) to a group of 27 volunteers. Then they zapped the volunteers' first molars with an electronic pulp test. They considered subjects successfully anesthetized if they didn't feel anything at the electrical dose (80 A) on two consecutive tries. Fifteen of the volunteers (55.6%) achieved that level.

Later, the researchers performed another experiment on the same volunteers, giving them an infiltration of 4% articaine (1:100,000 epinephrine). This time 19 (70.4%) were successfully anesthetized. The difference between the success rate with IANB and rate with infiltration was not significant (p = 0.60).

Mall teeth whitening under scrutiny in New Mexico

Mall teeth whitening under scrutiny in New Mexico

June 9, 2008 -- The New Mexico Board of Dental Health Care believes that mall teeth-whitening businesses could be detrimental to public health, the Cibola County Beacon recently reported.

DrBicuspid.com recently highlighted some of the dental industry's concerns regarding this trend and what several states are doing to improve regulation of these facilities.

In New Mexico, tooth whitening is classified as a dental procedure that can only be performed by a licensed dentist or licensed dental hygienist under the supervision of a licensed dentist and after the patient has been examined by a licensed dentist.

"The Board of Dental Health Care has directed the Regulation and Licensing Department to take appropriate measures to ensure that all teeth-whitening services offered to the public are in full compliance with state law and federal regulation," reported the Beacon.

Toothbrushing causes bacteria to enter bloodstream

Toothbrushing causes bacteria to enter bloodstream

June 9, 2008 -- NEW YORK (Reuters Health), Jun 9 - Brushing one's teeth is nearly as likely as removing a tooth to temporarily cause bacteria to enter the bloodstream, according to a report in the journal Circulation. This finding is concerning because bacteria in the blood can lead to a rare but potentially serious heart problem called infective endocarditis, the infection of the heart valves and chambers.

The risk of infective endocarditis with toothbrushing relative to dental procedures is unknown, Dr. Peter B. Lockhart, from Carolinas Medical Center in Charlotte, NC, and colleagues note. Although tooth removal is among the most likely of dental procedures to cause bacteria to enter the blood, toothbrushing can disrupt a larger amount of gum tissue.

To investigate these effects, Lockhart's group randomly assigned 290 patients scheduled for tooth extraction to toothbrushing followed by tooth extraction; tooth extraction with an antibiotic given beforehand; and tooth extraction with inactive "placebo" beforehand. None of the patients required antibiotics to prevent infection based on current guidelines.

Blood samples were drawn prior to toothbrushing or tooth extraction, then at 1.5, 5, 20, 40, and 60 minutes after the beginning of the procedures. Blood samples were cultured for bacteria.

Of 98 types of bacteria found in the blood samples, 32 were considered to be potential causes of infective endocarditis. One or more of these 32 microbes were found in 23% of patients in the toothbrushing group, 33% of those in the extraction/antibiotic group, and 60% of those in the extraction-placebo group.

At the 60-minute blood draw, 5% of the extraction-placebo group and 2% of the brushing group still had potentially disease-causing bacteria in their blood.

These findings suggest that brushing poses a risk for bacteria in the blood similar to that of a dental extraction, the authors note, and that antibiotic treatment beforehand is only partially effective in preventing this.

Source: Circulation, June 17, 2008.

Last Updated: 2008-06-09 17:07:48 -0400 (Reuters Health)