Failure rate of direct tooth restorations placed with conventional glass-ionomers compared to composite [protocol]

This protocol has been registered with the International Prospective Register for Systematic Reviews (PROSPERO) on the 10 July 2012 under registration number CRD42013006487 (Available online from http://www.crd.york.ac.uk/prospero/display_record.asp?ID=CRD42013006487).

REVIEW QUESTION: Do conventional glass-ionomer restorations, in patients with single and/or multi-surface cavities in posterior permanent teeth, have a higher failure rate than direct composite resin restorations?

SYSTEMATIC LITERATURE SEARCH: Databases: MEDLINE accessed via PubMed; CENTRAL accessed via Cochrane Library; Open access sources: Biomed Central, DOAJ; Regional databases: IndMed, SABINET; Grey-Literature sources: OpenSIGLE, Google Scholar.

SEARCH TERM DEVELOPMENT: Strings of search terms (containing MeSH and text search terms) together with Boolean operators will be developed and utilized for searching the databases.

ARTICLE SELECTION CRITERIA: Prospective clinical control trial; clearly reported parallel group design with dichotomous outcome measure; outcome measure: restoration failure due to fracture, wear, secondary caries, retention loss; Intervention in permanent posterior teeth; follow-up period: 1 year or longer with longest comparable result per study; trials comparing: composite versus amalgam, high-viscosity glass-ionomers versus amalgam, high-viscosity glassionomers versus composite. Trial exclusion criteria: Tunnel restoration, preventive resin restoration (sealed restoration) as intervention type; cermet, low-viscosity glass-ionomer cements; chemically cured composite resin, non-hybrid composite resins (macro/micro/midi filled); low-copper amalgam alloys; composite resin and/or amalgam restorations placed with glass-ionomer liner or base; no computable data reported; tooth cavities in anterior teeth, class V cavities or cavities on root/cervical tooth surfaces; tooth cavities extending into enamel, only.

DATA EXTRACTION: The information extracted from selected trials will include general trial information, information regarding bias risk; all data with relevance to the review question will be extracted in form of individual dichotomous datasets.

DATA ANALYSIS AND REPORTING: Relative and absolute point estimates with 95% Confidence intervals will be computed per dataset and statistical heterogeneity investigated; selection-, detection-, performance-, attrition-, publication bias risk will be assessed; a network meta-analyses will be conducted for adjusted indirect comparison of treatment efficacy between conventional glass-ionomer and composite resin on basis of amalgam restorations as the shared control intervention.