Abstract
Aim: To compare marginal seal at tooth-material and material-material interfaces in the proximal box in combined amalgam/composite resin restorations. Methods: Mesio-occlusal-distal (MOD) cavities were prepared in 35 premolars and permanent molars with carbide bur. The distal proximal box was restored with amalgam (Permite, SDI) until reaching the height of pulpal floor. Dental tissues were etched with 37% acid and a bonding agent (Bond 1-SF, Pentron) was applied and cured. Composite resin (Filtek Z250, 3M-ESPE) was placed in layers in the mesial proximal box and occlusally, and light cured. Marginal adaptation was evaluated at the following interfaces: amalgam-tooth (A), amalgam-composite resin (AC) and composite resin-tooth (C). Microleakage was evaluated by means of methylene blue infiltration after 7-day water storage and thermocycling regimen (1500 cycles). Microleakage was assessed as percentage depth of horizontal dye penetration. Results: ANOVA showed statistically significant difference between A-AC and A-C (p 0.05). Mean microleakage values were A (73.529/28.71), AC (34.118/34.6) and C (40.435/ 34.965), according to Tukey’s test. Conclusions: Although the bonding mechanism between amalgam and composite has not yet been completely explained, amalgam/composite resin interface exhibited the lowest microleakage scores. Since amalgam/composite resin restorations exhibited lower microleakage scores than composite resin on the cervical surface, combined restorations can be considered as a biological and aesthetic alternative to conventional Class II composite or amalgam restorations.
Highlights
Received for publication: February 09, 2013Accepted: May 22, 2013Correspondence to: Christina BoutsioukiKallidopoulou Str.54642, Thessaloniki, GreecePhone: +30 6945822764Fax: +30 2310863631Braz J Oral Sci. 12(2):[100-104]Secondary caries is still cause for composite resin restoration failure[1]
Marginal adaptation was evaluated at the following interfaces: amalgam-tooth (A), amalgam-composite resin (AC) and composite resin-tooth (C)
Teeth restored using composite resins are especially prone to this phenomenon due to stress generated within the tooth-restoration interface following resin contraction during polymerization, known as polymerization shrinkage 2
Summary
Secondary caries is still cause for composite resin restoration failure[1]. Should the accumulated polymerization contraction stress result in tooth-composite adhesive failure 3-4, bacterial aggregation at the disrupted tooth-restoration margin may occur resulting in microleakage and later secondary caries. Lower level of dentin mineralization, challenging moisture control for application of adhesive system, presence of tubular fluid and bonddegrading matrix-metalloproteinases hinder bonding to dentin 5, making composite placement a technique-sensitive procedure 7. Thereby, both polymerization shrinkage and quality of the bond seem to be responsible for the degradation of marginal adaptation.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
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 call
