Are posts necessary for the restoration of root filled teeth with limited tissue loss? A structured review of laboratory and clinical studies

Abstract

Guidelines for post placement are lacking in respect of the amount of tooth structure, particularly in cases in which ≥50% of coronal structure is preserved. The aim of this review was to provide evidence-based principles for the use of posts in the restoration of root filled teeth with limited tissue loss. A literature search of laboratory and clinical studies published between 2000 and 2014 was conducted in PubMed. Included studies contained at least one study group with root filled teeth restored without a post, presented at least one group with root filled teeth with limited tissue loss, and, in the case of laboratory studies, performed mechanical cycling prior to a fracture resistance test. Based on the evidence from laboratory studies, root filled premolars and molars with limited tissue loss can be restored without posts, particularly when total coverage is planned. However, when no cusp protection is provided, post placement appears to be beneficial in premolars. Evidence regarding the best restoration option for root filled incisors with limited tissue loss remains controversial. When total coverage is intended, reconstruction seems to be successfully performed by restoration with composite. However, some reports consider that post insertion increases fracture loads. The review of clinical studies demonstrated that survival of teeth with substantial tooth tissue is not influenced by the use of posts. Exceptions were found when only premolars were investigated; in these cases, post placement was associated with greater survival rates in crowned teeth and fewer root fractures in teeth without cusp protection.

Clinical performance and failure modes of pulpless teeth restored with posts: a systematic review

“…Ferrari et al 28 and Creugers et al 25 showed that presence of ferrule and preservation of coronal walls increased survival rates of post-restored teeth. Such findings confirm the importance of preserving tooth structure on the performance of endodontically-treated teeth, 41 which may be even more important than the choice of the core.…”

“…In cases of limited tissue loss, post placement does not seem to affect the survival of endodontically-treated teeth. 41 However, when a post is placed, the remaining dental structure influences the performance of root-filled teeth. Ferrari et al 28 and Creugers et al 25 showed that presence of ferrule and preservation of coronal walls increased survival rates of post-restored teeth.…”

A prospective study assessing the effect of coronal tooth structure loss on the outcome of root canal retreatment

“…, Aurelio et al . ), whilst others use more generic terms such as ‘substantial’ or ‘minimal dentine height’ remaining (Creugers et al . , Fokkinga et al .…”

“…There have been several suggestions on how to classify the amount of remaining sound coronal tooth structure in root filled teeth. Some authors refer to the percentage of residual tooth structure without defining how this percentage has been measured (Juloski et al 2014, Aurelio et al 2015, whilst others use more generic terms such as 'substantial' or 'minimal dentine height' remaining (Creugers et al 2005, Fokkinga et al 2007, limited loss of coronal tooth structure in teeth with mesial or distal caries with cusp preservation (Mannocci et al 2002).…”

In vitro methods to evaluate the mechanical behavior of teeth restored with post and core: a structured review

“…By means of in vitro studies, it is possible to standardize and to isolate a variable of interest, elucidating any doubts prior to conducting clinical studies 1 . However, over the past few decades, the validity of some in vitro dental materials studies has been questioned due to the variability in the methodological parameters, the lack of representativeness of the clinical mechanism of failure and the poor correlation with clinical behavior 2,3 .…”