Abstract
Composite resins for posterior tooth restorations have become a viable alternative to dental amalgam. Failures sometimes cannot be easily explained, and we hypothesize that a genetic component may influence longevity of restorations. We aimed to determine if there is any evidence for a difference in the performance of amalgams versus composite resin in extensive posterior restorations. We also aimed to determine if risk factors such as age, sex, smoking tobacco, alcohol drinking, diabetes status, and periodontal health status may have a role in the failures of extensive anterior composite restorations. Finally, we investigated if genetic variation in matrix metalloproteinases that are present in the mineralized dentin is associated with failure of composite resin. The data used to perform this research were obtained from the Dental Registry and DNA Repository project after screening 4,856 patients. All restorations were evaluated at times of 1, 2, and 5 years after the restoration placement. 6,266 amalgam and 2,010 composite restorations were analyzed in a total of 807 patients in a period of approximately 10 years (period corresponding to the database existence). An additional 443 extensive direct composite resin restorations in anterior teeth were also studied. Failure rates of amalgam and composite restorations are similar, and by the end of 5 years, composites outperformed amalgams slightly. Failures of anterior composite restorations occurred more often in males who smoked tobacco (p = 0.05), despite a similar number of females and males that smoked tobacco in the sample (116 individuals smoked tobacco, 54 females and 62 males). Alcohol drinking increased failure rate within 2 years (p = 0.03). We found a statistically significant association between matrix metalloproteinase 2 rs9923304 and failure of composite restorations (p = 0.007). Composite resins can replace amalgam restorations. Smoking tobacco and drinking alcohol will increase the chance of restoration failure.
Highlights
In 2008, Norway was the first country to completely ban amalgam dental restorations, quickly followed by Sweden and Denmark
Mineralized dentin contains Matrix metalloproteinase 2 (MMP2), MMP3, MMP8, and MMP9 and acidic resin components incorporated into etch-and-rinse adhesives and self-etch adhesives increase collagenolytic and gelatinolytic activities of demineralized collagen matrices
We show for the first time that genetic variation potentially affecting degradation of collagen is associated with failures of more extensive composite restorations
Summary
In 2008, Norway was the first country to completely ban amalgam dental restorations, quickly followed by Sweden and Denmark. This decision was motivated by concerns related to the composition of the amalgam and the existence of viable non-mercury filling substitutes (composite resins for the most part). Despite the evidence showing no health consequences for having dental amalgam restorations, the question persists regarding composites being able to provide the same performance of their metallic counterparts. We aimed to determine if risk factors, such as age, sex, smoking tobacco, alcohol drinking, diabetes status, and periodontal health status, may have a role in the failures of extensive anterior composite restorations. Since dentin MMPs are exposed and activated during the process of restoring a tooth with composite resin, they degrade type I collagen [8,9,10,11], we tested if genetic variation in MMPs are associated with composite restoration failures and show that the matrix metalloproteinase 2 (MMP2) may have a role in the failure of composite restorations
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
