Quintessence International, 08/1992

Through the report of a clinical case, the feasiblity and advanatages of repair and recontouring of complex amalgam restorations are discussed. In this patient, the kind of alloy used for the fractured restoration and the age of the restoration were known factors. Additional mechanical retention was prepared in both the old amalgam and the dentin, and the reapir was made with a high-copper alloy. The bond at the repair site was stable at the 2.5-year recall examination.

Many clinical applications have been recommended for glass-cermet cement because of its improved properties compared to the original glass-ionomer cements. It has also been accepted as a dentinal substitute that can strengthen teeth. In this paper, an additional clinical application for glass-cermet cement, the reinforcement of weakened endodontically treated roots, is suggested. This technique is in keeping with the trends of tooth conservation and the use of an adhesive restorative material in the restoration of severely damaged teeth by a conservative approach.

Administration of tetracycline to children or pregnant women is known to adversely affect the color of developing teeth. This case report suggests the possibility that discoloration from tetracycline may not be limited to tooth development in the child, but may also affect the adutl dentition. When give over long periods of time in adults , the tetracycline molecule is incorporated into the continuously forming secondary dentin. It is possible that chronic sun exposure of the incorporated tetracycline may cause the formation of areddish-purple oxidation product, resulting in discoloration of the permanent teeth.

This report describes a technique for repairing a fractured porcelain-fused-to-metal pontic by using an overcasting made from a castable ceramic material.

Dentists may want to consider using an update of a unique complete denture technique that saves total chair time and, therefore, decreases cost. The technique combines appointments two and three, during which time the dentist both makes the master impressions and records the maxillomandibular relationships. In the past, protection of the maxillomandibular relationship records during the subsequent laboratory work was a problem. By applying new, tough, and thin denture base materials to thetechnique, the dentist will be less likely to distort the maxillomandibular records while boxing and pouring the impressions.

Several recently marketed dentinal bonding agents modify, but do not remove, the smear layer. Some controversy exists as to whether the smear layer should be left in place or completely removed from preparations to be restored with composite resin systems. This study utilized scanning electron microscopy with energy dispersive x-ray analysis to evaluate the pathway of microleakage in a composite resin restorative material that utilizes a smear layer-mediated dentinal bonding agent. Microleakage occurred at the smear layer-dentin interface and progressed into both the smear layer and dentinal tubules, suggesting that the smear layer acts as a pathway for microleakage.

An anterior composite resin was evaluated in a clinical study of 93 Class III and Class IV restorations placed in patients aged 12 to 50 years. The restorations were evaluated at baseline, 6 months, and 1 year. Sixty-four (79%) of the 91 restorations examined at the 1-year recall were unchanged. Marginal discoloration and changes in surface appearance and marginal adaptation accounted for most of the changes. All changes appeared in patients younger than 14 years, which may indicate that the patiends had problems

The shear bond strength between enaeml and composite resin placed with an unfilled resin layer was tested under several conditions: The unfilled resin layer was either blown thin or left unthinned, and pre-cured alone or cured with the compsoite resin. Shear testing showed that the bond to enamel was slightly enhanced for Pekalux and was significantly enhanced for Durafill VS when the unfilled resin was not pre-cured. Thinning of unfilled resin slightly increased the bond strength of Pekalux and decreased the bond strength of Durafill VS. A majority of the specimens fractured at the composite resin-unfilled resin interface, and more than half of all interface failures occurred in specimens in which the unfilled resin had been pre-cured. The results indicated that the link between composite resin and the unfilled resin layer was enhanced by simultaneous curing.

To determine whether the use of intraligamentary anesthesia increases the incidence of dry socket, results of 305 extractions of mandibular molars in two groups of patients were studied. In the first group, inferior alveolar nerve block was applied, and, in the second, intraligamentary anesthesia was applied. A solution of 2% lidocaine with 1:80,000 epinephrine was used. Statistical analysis of the postoperative occurrence of dry socket indicated that the use of intraligamentary anesthesia did not result in a higher frequency of dry socket than did conventional anesthesia.

The aim of this study, which was conducted in a refugee camp of the African National Congress in Tanzania, was to analyze the caries experience in relation to perceived stress and sleeping problems and stressful experiences among South African political refugees. A sample of 194 persons, aged 11 to 39 years, was examined clinically and interviewed. There was a consistent association between caries experience and the different parameters for estimating perceived and experienced stress. In particular, the aggregation of different stress indicators seemed to be strongly related to higher caries experience.