Potential side effects of dental amalgam restorations

The aim of this study was to explore a possible association between health status and self-reported adverse effects related to dental amalgam restorations. A group of 50 consecutive patients (index group), referred for complaints self-related to dental amalgam restorations, was compared with a control group of individuals matched by age, sex and postal zip code. The patients underwent an oral, stomatognathic, medical and clinical chemistry examination. Mercury levels were examined in blood, urine and hair. The results revealed that somatic diseases were more common in the index group (38% versus 6%). Symptoms related to cranio-mandibular dysfunction were reported by 74% of the patients in the index group versus 24% in the control group, and were diagnosed in 62% and 36%, respectively. The oral health status and the number of amalgam surfaces were similar in the 2 groups. No positive skin patch test to mercury was found in any of the groups. The estimated mercury intake from fish consumption, occupational exposure, and mercury levels in blood and urine were also similar and far below levels, where negative health effects would be expected. The correlation between the number of amalgam surfaces and mercury levels in plasma and urine ( r = 0.43) indicated a release of mercury from dental amalgam restorations in both groups. Since the mercury levels were similar among index patients and controls, mercury was not a likely cause of the impaired health reported by the patients.     

Antibiotic prophylaxis in intraoral orthognathic surgery

A prospective randomized double-blind study was conducted to evaluate two prophylactic antibiotic regimens in a population of 40 patients undergoing intraoral orthognathic surgery. All patients received one intramuscular dose of 600,000 units procaine penicillin G and 400,000 units aqueous penicillin G preoperatively. Two million units aqueous penicillin G were administered intravenously every three hours intraoperatively and postoperatively three hours after the last intraoperative dose. One group of 20 patients then received 2 million units aqueous penicillin G intravenously every four hours for a total of 12 doses (two days) postoperatively. The second group of 20 patients received a placebo intravenously every four hours for a total of 12 doses (two days) postoperatively. Three infections occurred in the group of patients receiving the placebo postoperatively and none in the group of patients receiving the antibiotics postoperatively.     

Opinions of dentists and directors of nursing concerning dental care provision for Adelaide nursing homes

BACKGROUND: The complex oral health problems of nursing home residents have been well documented. However, the influences on residents' oral health status, including opinions and experiences of dental professionals and nursing home staff, have not yet been adequately investigated. METHODS: The baseline questionnaire component of this longitudinal study was mailed to all registered dentists practising in Adelaide and Adelaide nursing home directors of nursing (DONs). RESULTS: 413 dentists and 97 DONs indicated that Adelaide dentists' interest and training in nursing home dentistry was low. Dental service provision for nursing home residents was very low and dentists preferred to provide treatment at their dental practices. Few dental hygienists were working in nursing homes and dental professionals provided little educational assistance for nursing home staff. Dentists and DONs held several common and many varying perceptions of the problems associated with dental care provision in nursing homes. Both identified a group of nursing home environmental constraints and a lack of portable dental equipment. DONs further identified a group of resident related problems, and dentists a group of dental practice-related problems. CONCLUSIONS: These study results provide important information concerning problems with nursing home dentistry for dental service providers, educators, policy-makers, administrators and nursing home staff.     

Bonding of plastic teeth to denture base resins.

This study evaluated the bond strengths of some new and traditional resin denture teeth and denture base resins. It included regular monolithic acrylic resin teeth (Bioform), monolithic acrylic resin-IPN teeth (Bioform IPN), and multilithic acrylic resin-composite resin teeth (Vivosit), with relatively new light-activated resin (Triad), conventional heat-cured resin (Lucitone 199), and autopolymerizing resin (Hygenic) denture base materials. The results of four-point flexure testing showed that the traditional materials gave the highest bond strength values. The autopolymerizing resin systems demonstrated interfacial failure with all resin denture teeth, showing that the common practice of treating teeth with the respective autopolymerizing monomer failed to produce adequate bond strength. Combinations of acrylic resin, IPN, and multilithic denture teeth with light-activated resins gave results calling for improvements in basic bonding system design, since interface debonding was prevalent. No failures occurred between the lap-ridge region of the multilithic tooth system and conventional heat-cured denture base resin.     

The relationship between biologic concepts and fabrication of surgical guides for dental implant placement

This article reviews guidelines for construction of surgical guides to direct dental implant placement. Biologic principles are discussed with regard to the mesiodistal, buccolingual, and apicocoronal insertion of implants. The application of these data to develop surgical guides is discussed. Also, with respect to specific prosthetic reconstructions, a variety of guides are described that can be fabricated for partially and fully edentulous arches.     

Deformational posterior plagiocephaly: diagnosis and treatment.

OBJECTIVE: This study was designed to evaluate the effectiveness of helmet therapy (DOC band) in the correction of patients with moderate to severe posterior deformational plagiocephaly. DESIGN: In this prospective study, the infants were evaluated using 18 anthropometric measurements. PATIENTS: The charts of 248 patients seen between August 1, 1995, and July 31, 1999, were reviewed, and 125 met the criteria for inclusion in the study. All the patients had posterior deformational plagiocephaly with no other craniofacial deformities or medical conditions. Treatment was instituted prior to 1 year of age, and all patients were compliant with DOC band usage and had complete anthropometric measurements. RESULTS: The study recorded a 41.56% (p < .001) reduction in cranial vault asymmetry and a 40.23% (p <.001) reduction in cranial base asymmetry. Orbitotragial asymmetry was improved 18.72% (p = .0738). The age at which treatment was begun was not a significant factor in predicting treatment outcomes.     

Effect of pH on element release from dental casting alloys

Statement of problem. Dental casting alloys are subjected to transient acidity in the oral environment, yet most studies have not investigated the effects of these transient environments on elemental release from alloys. Elemental release is important because it plays a significant role in alloy biocompatibility. Purpose. It was hypothesized that acidic environments would increase elemental release from dental alloys during exposure and after the acidic environment was removed. This hypothesis was based on the known increase in release of nickel from nickel-based alloys in an acidic environment. Material and methods. High-noble, noble, and base metal casting alloys were exposed for 30 minutes to solutions with pH ranging from 1 to 7. Elemental release of representative elements was measured by means of atomic absorption spectrometry during the exposure and in the week after the exposure. This release was compared with elemental release in the week before the exposure. Results. High-noble and noble alloys were resistant to acidic environments. A pH of 4 did not increase elemental release during or after exposure. A pH 1 environment slightly elevated release of Ag, Cu, and Pd in some alloys. However, a Ni-based alloy released large amounts of Ni during the acidic exposure of pH 1 or 4, and more importantly, in the week after the exposure as well. Increased time of exposure to acid did not alter elemental release from noble or high-noble alloys, but markedly increased release from the Ni-based alloy. Conclusions. Transient exposure of casting alloys to an acidic oral environment is likely to significantly increase elemental release from Ni-based alloys, but not from high-noble or noble alloys. (J Prosthet Dent 1998;80:691-8.)