Biomedical subjects

H W Roberts

Publications and source records attributed to H W Roberts.

10 recordsLinked to original sources

PubMed2001

Cardiac risk stratification for postmyocardial infarction dental patients.

Traditional dental management guidelines of myocardial infarction survivors mandate a 6-month waiting period before elective treatment can be considered. Technological advances in cardiac disease diagnosis, management, and revascularization treatment may make this older mandatory 6-month waiting period obsolete. The purposes of this literature review are to provide an overview of the historical development of cardiac risk stratification and discuss current developments and guidelines in cardiac risk assessment. We hope that this review and update will stimulate the development of updated dental guidelines for treating the cardiac patient.

Clinical Protocols↗

PubMed2001

Potential health and environmental issues of mercury-contaminated amalgamators.

BACKGROUND: Dental amalgamators may become contaminated internally with metallic mercury. This contamination may result from mercury leakage from capsules during trituration or from the long-term accrual from microscopic exterior contaminants that result from the industrial assembly process. The potential health risk to dental personnel from this contamination is unknown. METHODS: The authors assessed used amalgamators from the federal service inventory for the amounts of mercury vapor levels, as well as the visual presence of mercury contamination. They evaluated these amalgamators for potential mercury vapor health risk, using established National Institute for Occupational Safety and Health methods and American Conference of Governmental Industrial Hygienists standards. RESULTS: Ten of the 11 amalgamators assessed had measurable mercury vapor levels. Four amalgamators were found to have internal static mercury vapor levels above Occupational Safety and Health Administration ceiling limit thresholds. During a simulated worst-case clinical use protocol, the authors found that no amalgamators produced mercury vapor in the breathing space of dental personnel that exceeded established time-weighted federal mercury vapor limits. CONCLUSIONS: Amalgamators may be contaminated internally with metallic mercury. Although the authors detected mercury vapor from these units during aggressive, simulated clinical use, dilution factors combined with room air exchange were found to keep health risks below established federal safety thresholds. CLINICAL IMPLICATIONS: Dental personnel should be aware that amalgamators may be contaminated with mercury and produce minute amounts of mercury vapor. These contaminated amalgamators may require disposal as environmentally hazardous waste.

Air Pollution, Indoor↗

PubMed2000

Dental unit waterline antimicrobial agents' effect on dentin bond strength.

BACKGROUND: In response to concerns of bacterial biofilm colonization of dental unit waterlines, a wide range of commercial intermittent and continuous chemical treatments for dental unit waterlines have been developed and marketed. There has been little research on the possible effect of continuous chemical treatment regimens on dentin-bonding agents. The authors evaluate the effect of four proposed antimicrobial agents used in dental unit waterlines on dentin bond strength. METHODS: The authors used a fifth-generation dentin-bonding agent to bond composite cylinders to molar dentin surfaces. They then used selected antimicrobial agents as rinsing agents after conditioning. The composite cylinders were shear tested, and their fracture strengths were compared statistically. RESULTS: All proposed antimicrobial agents reduced dentin bond strength. Proposed waterline treatment regimens of a diluted mouthrinse and chlorhexidine significantly reduced dentin bond strength compared with sodium hypochlorite and citric acid regimens. CONCLUSION: Dental professionals should be aware of potential interactions between dental unit waterline antimicrobial agents and dentin-bonding agents. Further research in this area is warranted, as the clinical implications are uncertain at this time. CLINICAL IMPLICATIONS: Dental unit waterline antimicrobial agents may adversely affect dentin bonding strength.

Adhesives↗

PubMed2000

Coronary artery stents: review and patient-management recommendations.

BACKGROUND: Coronary artery stents are metallic scaffold devices that physically support narrowed coronary arteries to alleviate symptoms of ischemic coronary artery disease. They are placed during invasive procedures similar to that of percutaneous transluminal coronary angioplasty, and patients are maintained with antiplatelet medications to lessen the chances of stent stenosis. METHODS: The authors provide a brief overview of coronary artery stents and discuss the dental management of patients who have received stents. CONCLUSIONS: After stent placement, patients usually are maintained with antiplatelet regimens, which may necessitate choosing medications that do not potentiate their effects. Any discussion as to the possible need for antibiotic prophylaxis of patients with stents largely is missing from the literature. Recent literature, however, indicates that antibiotic prophylaxis, if required, may only be needed during the first few weeks after stent placement. CLINICAL IMPLICATIONS: Dental professionals should become knowledgeable about coronary artery stents. Although these devices have a higher success rate than other procedures in alleviating symptoms of ischemic coronary artery disease, some patients are still at risk of experiencing significant cardiac events.

American Hospital Association↗

PubMedDate not supplied

Atypical presentation of odontogenic pain.

Pain referral patterns in the head and neck regions can be complex and frustrating for practitioners to diagnose and treat. This clinical case report involves a patient who did not respond to initial medical treatment for headache pain. The pain was found to be referred from a carious and pulpally involved mandibular molar that interestingly responded normal to pulp vitality testing.

Adult↗

PubMedDate not supplied

The use of resin composite pins to improve retention of Class IV resin composite restorations.

This study evaluated the effect of an intracoronal resin composite pin on Class IV resin composite restorations. A control group of 16 bovine teeth was prepared with standardized conventional Class IV preparations. For an experimental group, 16 similar Class IV preparations were made, with the addition of an intracoronal pin channel prepared with a #330 bur into the dentin. All specimens were restored with Herculite XRV and OptiBond according to the manufacturer's recommendations. After one week, specimens were placed in an Instron Universal Testing Machine and loaded at 90 degrees to the long axis until the restorations failed. Results indicated that the mean fracture load of the Class IV restoration group, with the resin composite pin, was 36% higher than the conventional Class IV group (p = 0.02). An intracoronal resin composite pin may aid the retention and resistance form of complex resin composite restorations.

Animals↗

PubMedDate not supplied

Repair of non-carious amalgam margin defects.

This study investigated the microleakage associated with the repair of non-carious amalgam defects using flowable resin composite. Occlusal amalgam preparations were accomplished on 36 non-carious mandibular molars. A standardized 40-micron marginal defect was made by condensing amalgam against a mylar matrix strip. Specimens then underwent a corrosion protocol designed to simulate intraoral corrosion seen with amalgam restorations. The resultant specimens were divided into three treatment groups: 1) No treatment (control); 2) Air abrasion of the amalgam defect surface, acid etching of both amalgam and enamel surfaces, then placement of a flowable composite and 3) Air abrasion of the amalgam defect, application of a fifth-generation dentin bonding agent and placement of the flowable composite. Specimens were thermocycled, sealed with glass ionomer and fingernail polish to within 1 mm of repaired margins, then immersed in basic fuchsin for 24 hours. Specimens were sectioned and microleakage assessed. Results indicated that a flowable resin composite significantly reduced marginal microleakage compared to the control (p < 0.05). There was no difference in microleakage between flowable resin composite repairs done with or without the use of a dentin-bonding agent.

Acid Etching, Dental↗

PubMedDate not supplied

Swing-lock removable partial dentures.

The swing-lock removable partial denture (RPD) is a little-taught RPD concept that offers clinicians additional choices in the treatment of perplexing situations involving periodontally compromised dentitions, missing key abutments, and other clinical situations in which a conventional RPD design may not be feasible. This article reviews past and current literature concerning the swing-lock RPD and provides some clinical and laboratory considerations involving the treatment planning and fabrication of this often-useful RPD.

Contraindications↗

PubMedDate not supplied

The use of dental amalgam in pediatric dentistry: review of the literature.

Dental amalgam is widely used as a restorative material even though it is not esthetic and there has been extensive anti-amalgam rhetoric. Although other materials have improved greatly, amalgam has the proven safety record and best cost-to-benefit ratio. Clinical evidence indicates that, in the posterior permanent dentition--where esthetics is not a primary concern--the small, minimally prepared, amalgam restoration, with its margins and any caries-susceptible fissures sealed with resin fissure sealant, is the restoration with the best survival. Amalgam also remains the best direct restorative option when larger restorations are required. In the primary dentition, the data indicates that resin-based composite and resin-modified glass-ionomer serve very well.

Child↗

PubMedDate not supplied

Clinical consideration for infective endocarditis antibiotic prophylaxis.

American Heart Association (AHA) guidelines to prevent infective endocarditis recommend the use of antibiotic prophylaxis to treat hypertrophic cardiomyopathy caused by mitral regurgitation. The syndrome of congestive heart failure is frequently seen with clinical findings similar to those of hypertrophic cardiomyopathy, but antibiotic prophylaxis is not specifically recommended in the current AHA guidelines for congestive heart failure. Clinicians should be aware of the incidence of valvular abnormalities in congestive heart failure, and other cardiomyopathies, and consider the use of infective endocarditis antibiotic prophylaxis per AHA guidelines.

Antibiotic Prophylaxis↗