Do laboratory results concerning high-viscosity glass-ionomers versus amalgam for tooth restorations indicate similar effect direction and magnitude than that of clinical controlled trials? - A meta-epidemiological study [protocol]

A large percentage of evidence concerning dental interventions is based on laboratory research. The aim of this metaepidemiological study is to establish whether valid clinical inferences and recommendations can be made on basis of the current laboratory evidence concerning high-viscosity glass-ionomer cement (HVGICs) versus amalgam as materials for placing restorations in permanent posterior teeth for daily dental practice. HVGICs may offer a suitable clinical alternative to amalgam for placing permanent restorations in load-bearing posterior teeth. If such statement is true then invalid negative clinical inferences from poor in-vitro properties of the material may lead to erroneous rejection of HVGICs in clinical practice. However, if negative clinical inferences from in-vitro evidence against the material are valid than the rejection of HVGICs will be justified and consequently protects patients from unwarranted restoration failures, treatment expenses and discomfort. This meta-epidemiological study may assist in establishing the current evidence in regard to the question, whether valid clinical inferences and recommendations can be made on basis of the current laboratory evidence to this topic.