Procera all-ceramic crowns: a new approach to an old problem?

The effect of endodontic access on all-ceramic crowns: A systematic review of in vitro studies

OBJECTIVES

The aim of this systematic review was to identify from in vitro studies the effect of endodontic access on the fracture resistance and damage around the access cavity of all-ceramic crowns.

DATA

The articles identified were screened by two reviewers according to inclusion and exclusion criteria. The reference lists of articles advanced to second round screening were hand searched to identify additional potential articles. The risk of bias for the articles was independently performed by two reviewers.

SOURCES

An electronic search was conducted on PubMed/Medline, Web of Science, Scopus and Embase databases with no limitations.

STUDY SELECTION

383 articles were identified, of which, eight met the inclusion criteria and formed the basis of this systematic review. Factors investigated in the selected articles included the, presence of microcracks at the access cavity, repair protocol, ceramic type, crown fabrication method, luting agent and grit size of the diamond bur. The risk of bias was deemed to be high for three, medium for two and low for three of the reviewed studies. The high level of heterogeneity across the studies precluded meta-analyses.

CONCLUSION

Based on the currently available scientific evidence, a 'best practice' protocol with regard to improving the fracture resistance of endodontically accessed and repaired all-ceramic crowns cannot be conclusively identified. However, some key factors which potentially impact on the fracture resistance of endodontically accessed and repaired all-ceramic crowns have been isolated. Cautious clinical interpretation of these factors is concluded for the maintenance of the crown as a permanent restoration.

CLINICAL SIGNIFICANCE

Key factors which impact on the fracture resistance of endodontically accessed and repaired all-ceramic crowns have been isolated from in vitro studies. Cautious clinical interpretation of these factors is advised for the maintenance of the crown as a permanent restoration.

Ceramic dental biomaterials and CAD/CAM technology: state of the art

PURPOSE

Ceramics are widely used as indirect restorative materials in dentistry because of their high biocompatibility and pleasing aesthetics. The objective is to review the state of the arts of CAD/CAM all-ceramic biomaterials.

STUDY SELECTION

CAD/CAM all-ceramic biomaterials are highlighted and a subsequent literature search was conducted for the relevant subjects using PubMed followed by manual search.

RESULTS

Developments in CAD/CAM technology have catalyzed researches in all-ceramic biomaterials and their applications. Feldspathic glass ceramic and glass infiltrated ceramic can be fabricated by traditional laboratory methods or CAD/CAM. The advent of polycrystalline ceramics is a direct result of CAD/CAM technology without which the fabrication would not have been possible.

CONCLUSIONS

The clinical uses of these ceramics have met with variable clinical success. Multiple options are now available to the clinicians for the fabrication of aesthetic all ceramic restorations.

First impressions count

The art and craft of recording intra-oral anatomy successfully with dental impressions relies on the interaction of three critical factors--the 'golden triangle of impression-taking': an appreciation of the anatomical features to be recorded, the material used to take the impression and the clinical handling/operative technique applied. This paper aims to discuss the three factors and their inter-relationships, detailing clinical tips for successful, reproducible and consistent outcomes.

CLINICAL RELEVANCE

Obtaining accurate dental impressions is the key to success in a wide range of clinical restorative procedures. This paper offers clinical advice to practitioners to plan and then take predictable, good quality impressions for their restorative cases.

Crowns and extra-coronal restorations: materials selection

Materials selection is the second in the series on crowns and other extra-coronal restorations. Some of us are less than inspired by dental materials science. Nevertheless, many of the things that concern us clinically with crowns and their alternatives are based on material properties. We worry about the strength of the restoration, how well it fits and its aesthetics. We also worry about wear, occlusal control and biocompatibility. Not least of our concerns are dental laboratory charges, which inevitably have to be passed on to the patient.