Title There is No Difference Between Cement-Retained and Screw-Retained Implant Supported Crowns in Developing Marginal Bone Loss, but Screw Retained Crowns May Have a More Favorable Soft Tissue Response
Clinical Question For a patient receiving a crown restoration on a dental implant, will a screw-retained implant supported crown, as compared to a cement-retained implant supported crown, have a lower risk of marginal bone loss or soft tissue inflammation?
Clinical Bottom Line For a patient receiving a crown restoration on a dental implant, screw-retained, implant supported crowns and cement-retained, implant supported crowns appear to have similar risks for marginal bone loss and soft-tissue recession, but cement-retained crowns may have a greater risk for peri-implant soft tissue inflammation.
Best Evidence  
PubMed ID Author / Year Patient Group Study type
(level of evidence)
23297703de Brandao/2013Nine studies met the inclusion criteria.Meta-Analysis
Key resultsNine studies showed minimal differences in the marginal bone loss around dental implants restored with cement and screw retained crowns. “Pooled mean marginal bone loss was 0.53 mm (CI 95%, 0.31-0.76 mm) for cement-retained prostheses and 0.89 mm (CI 95%, 0.45-1.33 mm) for screw-retained prostheses.”
16907767Weber/2006152 ITI dental implants placed in 80 patients in the maxillary anterior region.Prospective Cohort Study
Key resultsThe study failed to identify differences in soft tissue recession or keratinized tissue levels between cement and screw retained crowns in three years after loading. Plaque and bleeding indexes were higher for the cement-retained crowns compared with screw-retained crowns.
Evidence Search ("bone screws"[MeSH Terms] OR ("bone"[All Fields] AND "screws"[All Fields]) OR "bone screws"[All Fields] OR "screw"[All Fields]) AND retained[All Fields] AND ("dental cementum"[MeSH Terms] OR ("dental"[All Fields] AND "cementum"[All Fields]) OR "dental cementum"[All Fields] OR "cement"[All Fields] OR "dental cements"[MeSH Terms] OR ("dental"[All Fields] AND "cements"[All Fields]) OR "dental cements"[All Fields]) AND retained[All Fields] AND ("bone diseases, metabolic"[MeSH Terms] OR ("bone"[All Fields] AND "diseases"[All Fields] AND "metabolic"[All Fields]) OR "metabolic bone diseases"[All Fields] OR ("bone"[All Fields] AND "loss"[All Fields]) OR "bone loss"[All Fields])
Comments on
The Evidence
Validity: Overall, the validity of the finding is limited. The systemic review identified nine studies meeting inclusion criteria, with only two having a direct comparison between treatment approaches. Also, a number of factors of potential importance to the outcomes assessed, such as sulcus depth, were not considered. The cohort study did not have randomization or standardization of treatments indications. It is entirely possible that differences seen in soft tissues may be related to different indications across the 5 study sites for single or multiple implant restorations. This was not addressed in the study analysis. Also, this study is based on secondary analysis of a longitudinal study lessening the value of the statistical findings. Perspective: There is limited high quality evidence to address this question. While these two studies, in particular the systematic review, begin to address this issue, the answer to this question is incomplete and the role for many of the factors with potential to impact these clinical outcomes remains unresolved.
Applicability This information may benefit a practitioner in deciding to restore a dental implant with a screw- or cement-retained implant supported crown.
Specialty (Periodontics) (Prosthodontics) (Restorative Dentistry)
Keywords Cement-Retained crown, Screw-Retained crown, Dental implant
ID# 2744
Date of submission 06/24/2014
E-mail saadalmojel@yahoo.com
Author Saad Almujel
Co-author(s) Abdulmohsen Alqasir and Teresa Nguyen
Co-author(s) e-mail abood6000@gmail.com, NguyenT16@livemail.uthscsa.edu
Faculty mentor Thomas Oates, DMD, PhD
Faculty mentor e-mail OATES@uthscsa.edu
Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)
None available
Comments and Evidence-Based Updates on the CAT
None available