Evidence summary: which dental liners under amalgam restorations are more effective in reducing postoperative sensitivity?

Abstract

Since August 2009, members of the Primary Care Dentistry Research Forum (www.dentistryresearch.org) have taken part in an online vote to identify questions in day-to-day practice that they felt most needed to be answered with conclusive research. The question that receives the most votes each month forms the subject of a critical appraisal of the relevant literature. Each month a new round of voting takes place to decide which further questions will be reviewed. Dental practitioners and dental care professionals are encouraged to take part in the voting and submit their own questions to be included in the vote by joining the website. The paper below details a summary of the findings of the ninth critical appraisal. In order to address the question raised by dentistry research forum, first a search was conducted for systematic reviews on the topic. There was one systematic review retrieved comparing bonded amalgam restorations versus non-bonded amalgam restorations. However, there was no other systematic review identified assessing the effectiveness of dental liners under amalgam restorations in general. Therefore, a search was conducted for any randomised controlled trial (RCT) comparing use of a lining under amalgam restorations versus no lining or RCTs comparing differing lining materials under amalgam against each other. There were eight relevant RCTs identified. Due to the low quality, small sample sizes or lack of adequate reporting of the outcome data, the evidence is inadequate to claim or refute a difference in postoperative sensitivity between different dental liners. Further well-conducted RCTs are needed to answer this question. These RCTs would be preferably included and synthesised in a systematic review.

Awareness Regarding Use of Lining Under Posterior Composite Restorations Among General Dentists of Lahore

“…The use of liners and bases is traditionally associated with amalgam, mainly because these materials are necessary to provide thermal insulation between amalgam and underlying vital dentine 12 . Operative Dentistry textbooks provide us with guidelines for placement of liners under posterior restorations.…”

Analysis of amalgam restorations done in class 1 cavities in a private dental college - A retrospective study

“…The varnish is natural gum, also known as a synthetic resin which is dissolved in the organic solvent (Edwards, 1978). It reduces leakage around the margins and prevents the microleakage of amalgam into dentin (Nasser, 2011). Twenty-ive patients had varnish as their pulp protecting agent which is most likely due to the shallow nature of the cavity.…”