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J C Setcos

Publications and source records attributed to J C Setcos.

45 records · Page 3Linked to original sources
PubMedDate not supplied

Dental materials: 1995 literature review.

This critical review of the published literature on dental materials for the year 1995 has been compiled by the Dental Materials Panel of the United Kingdom. It continues the series of annual reviews started in 1973 and published in the Journal of Dentistry. Emphasis has been placed upon publications which report upon the materials science or clinical performance of the materials. The review has been divided by accepted materials classifications (fissure sealants, glass polyalkenoate cements, resin composites, dentine bonding, dental amalgam, endodontic materials, casting alloys, investment materials, resin-bonded bridges and ceramo-metallic restorations, all ceramic restorations, denture base and soft lining materials, impression materials, dental implants, orthodontic materials and biomechanics). Three hundred and thirty articles published in 68 titles have been reviewed.

Biomechanical Phenomena↗
PubMedDate not supplied

Bonding of amalgam restorations: existing knowledge and future prospects.

A number of laboratory and clinical studies over the last 15 years have explored the potential advantages of bonding amalgam to tooth surfaces. Bond strengths have been reported to range from 2 to 20 MPa, with higher bond strengths reported for filled adhesives. Most studies agree that the use of bonding results in a considerable reduction of microleakage, when compared with copal varnish or no lining. The use of bonding provides retention in vitro that is equivalent to, or better than, the use of mechanical undercuts. Most studies on strength of restored teeth report an improvement in resistance to fracture or cuspal flexing as measured by strain gauges. Penetration of secondary caries along the interface has been found to be inhibited by bonding. The mode of failure of bonded amalgams has generally been reported to be mixed, but predominantly between the resin and amalgam. In vitro studies have reported one potential problem in the incorporation of resin into amalgam, which may cause a decrease in strength of the restoration. The clinical studies of bonded amalgams that have been published to date are of short duration, indicating that when traditional preparations are used, no problems are seen with bonding, but also no advantages, as measured by clinical assessment criteria. However, some studies show that bonded amalgam may be useful for procedures where non-bonded amalgams would be expected to be lost, namely in preparations with little, if any, mechanical retention. It was concluded that, while there are various in vitro studies demonstrating that bonded amalgams have advantages of improved retention and tooth reinforcement and decreased marginal microleakage and secondary caries, the operative technique is more complicated and there are few advantages yet evident from clinical studies in conventional preparations having mechanical retentive features. However, there is evidence accruing from clinical studies that bonding of amalgam can be favorably used to extend the range of usage of amalgam to non-retentive conservative preparations, and toward the other extreme, as an adjunct to other forms of retention in large compound restorations.

Adhesives↗
PubMedDate not supplied

Treatment selections for fissured grooves of permanent molar teeth.

Twenty dentists from selected dental school departments were asked to examine thirteen areas of fissured grooves or pits in extracted molars, and select a treatment from a list of options for each designated groove area, as if each was on a separate tooth. There was a wide variation in initial treatment selections with (29 percent) amalgam and (25 percent) resin sealants being the most common. Pediatric dentists were significantly more conservative in both their original and later diagnoses than were the other dentists in this study.

Decision Making↗
PubMedDate not supplied

Resin denture bases: review of accuracy and methods of polymerization.

Traditional compression molding and heat-activation methods for polymerization of denture base resins have been widely used. Studies have shown that stresses introduced during processing can lead to the distortion of denture bases. Chemical-, microwave-, and light-energy activation, and various combinations (including polymerization under pressure) have been offered as alternative ways to make dentures. These methods have been attempts to improve the accuracy of fit of the dentures, but sometimes the goal has also been to provide a more convenient laboratory technique. This extensive review covers studies that have investigated the accuracy of acrylic and other types of resins for making dentures using the known range of fabrication methods.

Acrylic Resins↗
PubMedDate not supplied

The sealed composite resin restoration.

This composite restoration-sealant combination is only to be considered for the small pit and fissure caries lesion. Bitewing radiographs should indicate no smooth surface interproximal caries in the teeth to be restored in this manner. All teeth treated with the composite restoration-sealant combination should be carefully evaluated at periodic recall visits. There is no single perfect conservative restoration for the young patient. Each of us must decide, on an individual basis, the appropriate type of procedure we elect to use. The sealed composite resin restoration can be very effective in carefully selected cases.

Composite Resins↗
PubMedDate not supplied

Noise levels encountered in dental clinical and laboratory practice.

PURPOSE: The aim of this study was to determine the noise levels made by different clinical hand-pieces, laboratory engines, and other significant equipment such as ultrasonic scalers, amalgamators, high-speed evacuation, and other items. MATERIALS AND METHODS: Sound levels were measured at four dental practices and three dental laboratories selected as representative of a variety of workplaces to reveal a range of noise. The noise levels were determined using a precision sound level meter, which was positioned at ear level and also at 2 meters distance from the operator. RESULTS: Virtually all noise levels at the dental clinics were below 85 dB(A). The noise levels in the dental laboratories had much higher maxima, with some cutting activities, steam cleaning, and sandblasting up to 90 dB(A), and compressed air blasts with a maximum of 96 dB(A). CONCLUSIONS: The noise levels in the dental clinics are considered to be below the limit of risk of hearing loss. However, technicians and other personnel who spend many hours in noisy dental laboratories may be at risk if they choose not to wear ear protection.

Dental High-Speed Equipment↗