Crowns and other extra-coronal restorations: cores for teeth with vital pulps.

Cores for teeth with vital pulps is the seventh in the series of crowns and other extra-coronal restorations. A core is defined as 'that part of a preparation for an indirect restoration consisting of restorative material'. This article questions the need for routine pin placement and addresses the following issues--removal of existing restorations, the need for a core, core materials, core retention, and problem solving.

The relevance and effect of amalgam replacement in subjects with oral lichenoid reactions.

In this study we examined the prevalence of mercury hypersensitivity in patients with oral lichenoid reactions (OLR) and the effect of amalgam replacement in subjects with amalgams adjacent to OLR irrespective of their mercury sensitivity status. One hundred and ninety-seven patients with oral problems were examined: 109 with OLR, 22 with oral and generalized lichen planus, and 66 with other oral diagnoses, including aphthous ulcers and orofacial granulomatosis. Nineteen per cent of patients with OLR reacted to mercury on patch testing, significantly more than in those with generalized lichen planus (0%) and in those with other oral diagnoses (3%). Twenty-two patients with OLR and adjacent amalgams had amalgam replacement and, in 16 of 17 mercury-positive subjects and three of four mercury-negative subjects, the OLR resolved after amalgam removal. In conclusion, we found a significantly increased prevalence of mercury hypersensitivity in patients with localized OLR in comparison to subjects with other oral problems. Amalgam replacement resulted in resolution of OLR in the majority of patients with amalgams adjacent to OLR irrespective of their mercury sensitivity status.

Resolution of lichen planus following removal of amalgam restorations in patients with proven allergy to mercury salts: a pilot study.

Thirteen patients with symptomatic oral lichen planus had been shown by patch testing to be allergic to ammoniated mercuric chloride. Replacement of amalgam restorations in these patients effected an improvement in all but one case. In some cases the resolution of symptoms was dramatic following the replacement of one or two fillings. The authors feel that the removal of all amalgam fillings need not be necessary except in the most intractable case.

Allergic reactions to rubber gloves in dental patients: report of three cases.

Three cases of allergy to rubber are described, in which the patients exhibited peri-oral rashes following dental treatment by personnel wearing latex rubber gloves. Two of the patients were aware of possible allergy to domestic rubber products but did not reveal this as part of their medical history. With the increase in numbers of dentists wearing rubber gloves it is probable that there will be many more such cases reported in the future. Rubber products must then be added to the list of potential allergens which may be of some import to the practice of dentistry.

The clinical performance of a posterior composite resin restorative material, Heliomolar R.O.: 3-year report.

A posterior composite resin restorative material was evaluated over a 3-year period by means of a controlled clinical trial. A total of 52 composite resin restorations and 52 amalgam alloy restorations were included in this trial, and were examined with regard to marginal integrity, surface texture, anatomical form and proximal contact with adjacent teeth. There were no significant differences in clinical performance between test and control materials, which both gave good service over the period of evaluation. Only five restorations (one of amalgam and four of composite resin) failed during the trial. Plastic replica dies were used to support the clinical examinations of the restorations, and such dies were found to be helpful.

Tissue necrosis after using an arsenical endodontic preparation: a case report.

A case is reported of severe loss of alveolar bone in the maxilla, as a result of leakage into the tissues of an arsenical paste from the pulp chamber of an endodontically 'treated' tooth. The history of the use of arsenic in dentistry is discussed, as are the hazards inherent in the use of this outmoded and dangerous medicament.

Composite resin as a means of improving the appearance of periodontally involved teeth.

Composite resin has become established not only as a material for restoring carious teeth, but also as a means of veneering discoloured or misshapen teeth. This case report describes how composite resin was used to improve the appearance of a tooth which had become unsightly as the result of a combination of gingival recession and attrition. This was done by veneering both the root surface and the cervical area of the crown.

The use of an analog type apex locator to assess the position of dentine pins.

An analog type apex locator was used to check the position of dentine pins. The teeth restored with the pins were reviewed. The analog type apex locator was easy to use and the readings obtained correlated well with the presence or absence of later symptoms from the tooth. This electrical method of checking pin position was more discerning than the method of direct observation.

The role of closed circuit television in the teaching of operative dentistry.

Closed circuit television has been used in the Department of Operative Dental Surgery of the University of Newcastle-upon-Tyne since 1966. The medium has played an increasingly important role in the teaching of technique courses, especially after 1978 when the large 80-place teaching laboratory of the newly-built Dental School was commissioned.

Mercury vapour levels in a domestic environment following breakage of a clinical thermometer.

Following the breakage of a clinical thermometer in the kitchen of the author's own home, mercury vapour was found to be present in most rooms, but not in concentrations which exceeded the current threshold limit value (TLV). However, assuming a more stringent standard of safety, based on continuous exposure to mercury vapour, it was noted that some of the readings could be considered to be excessive, although these were of a freakish and transient nature. In reality the overall time-weighted average exposure of the occupants was within reasonable limits. Lack of ventilation was a major factor in maintaining discernible levels of vapour over a 3-week period. However, the advent of mild weather was instrumental in dispersing the vapour, by allowing the opening of windows. The residual mercury on the floors would seem to have evaporated, so that no long-term health risk ensued. Cross contamination of the hallway carpet was noted indicating that mercury had been transported on the soles of feet and shoes.