View the CAT printer-friendly / share this CAT
Title Bisphenol A (BPA) Release From Resin Composite Material is Detectable But Not Clinically Significant
Clinical Question In patients with recently placed composite restorations, is the release of BPA clinically significant?
Clinical Bottom Line Elevated BPA levels in serum or urine are detected immediately after restoration placement, but significantly below the daily recommended allowance for BPA exposure levels by the Environmental Protection Agency (EPA). However, longer-term levels were not measured, which may be important since BPA may be released as a degradation byproduct of dental composites.
Best Evidence (you may view more info by clicking on the PubMed ID link)
PubMed ID Author / Year Patient Group Study type
(level of evidence)
#1) 27083778Maserejian/201691 people, ages 3-17Prospective Cohort Study
Key resultsAn average elevated change in levels of BPA (0.87 ng/ml excluding one outlier) in urine samples was measured one day after placement of a resin composite restoration. The levels returned to baseline by 14 days and remained there at 6 months.
#2) 23204083Kingman/2012172 adultsProspective Cohort Study
Key resultsIncreased salivary BPA levels (0.21 ng/ml) were detected 1 hour after composite restoration placement, but levels returned to baseline by 24 hours. Urine BPA levels increased by 43% compared to baseline at 9-30 hours, but no further measurements were taken.
#3) 21664675Van Landuyt/201122 in vitro studiesMeta-Analysis
Key resultsResin degradation due to the hydrolysis of ester bonds causes failure of the hybrid layer. When ester groups of methacrylate resin composite breakdown, acid is produced, similar to lactic acid-induced demineralization. Measuring out to 1 year, it was found that these processes can lead to failure of the resin composite due to degradation. The implication for BPA release is that longer term studies for BPA release are needed since BPA may be a byproduct of long-term composite degradation.
Evidence Search (("bisphenol A"[Supplementary Concept] OR "bisphenol A"[All Fields] OR "bisphenol a"[All Fields]) AND composite[All Fields] AND restorations[All Fields]) AND ("loattrfull text"[sb] AND "2006/11/12"[PDat] : "2016/11/08"[PDat])
Comments on
The Evidence
Validity: Subjects served as their own controls using pre- and post-treatment measurements. More than 80% completed the treatment. There was no blinding of the patients or providers to the treatment or measurements made. Maserejian had a longer follow-up time (6 months) compared to Kingman (30 hours). Subjects were from a wide age-range between the two studies. Though the Van Landuyt study is a meta-analysis, it reviews only in vitro studies. The majority of studies measuring eluents are in vitro due to the difficulties is measuring released quantities of eluents from composite resin in the oral environment or the unknown potential harm to patients. Perspective: BPA is part of the monomer bisphenol A glycidyl dimethacrylate, which is used in the vast majority of dental composites. Unreacted monomer can be degraded by esterases in the mouth and release BPA. The number and size of composite restorations, in addition to other sources of exposure to BPA, need to be considered to have a comprehensive understanding of the potential harm. Recommended daily allowance for exposure to BPA in a 70-Kg man is 3.5x106 ng/day and 0.5x106 ng/day for a 10-Kg child. Additional long-term research is needed to evaluate potential released levels of BPA due to material degradation and failure and its consequences.
Applicability In children and adults, transient detectable levels of BPA are present in saliva or urine up to 30 hours after placement of a resin composite restoration. The levels are significantly below the recommended daily allowance by the EPA for BPA exposure. Long-term consequences of exposure to BPA due to material breakdown are unknown at this time. Dentists must be aware of the risks and benefits to any material used and be able to discuss this with patients to allow for educated dental treatment decisions.
Specialty/Discipline (General Dentistry)
Keywords Bisphenol A, resin composite
ID# 3105
Date of submission: 11/08/2016spacer
E-mail sathissarat@livemail.uthscsa.edu
Author Jessica Sathissarat, DDS
Co-author(s) e-mail
Faculty mentor/Co-author Kyumin Whang, BS, MS, PhD
Faculty mentor/Co-author e-mail whang@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?)
post a rationale
None available
Comments on the CAT
post a comment
None available

Return to Found CATs list