Edition V16N03 | Year 2019 | Editorial Artigo Inédito | Pages 22 to 54
Introduction: This is the fourth article of a series of six manuscripts about composite resins in the last 10 years. The polymerization shrinkage is part of photopolymerization process and may cause shrinkage stress. It may be related to microleakage, enamel cracks, postoperative sensitivity and secondary caries. The aim of this literature review is to synthesize shrinkage polymerization data of different composite resins and discuss the postoperative sensitivity results of several clinical studies. Methods: A search in PubMed database was performed and 25 and 24 articles were select for polymerization shrinkage and postoperative sensitivity, respectively. Results: Polymerization shrinkage, shrinkage stress and post-gel shrinkage are directly related. Factors such as resin composition, polymerization conditions and restorative technique influenced these properties. Bulk fill composites presented lower or similar values to conventional composites for both polymerization shrinkage and shrinkage stress. Fluid conventional composites showed the highest values for both properties. Postoperative sensitivity ranged from 0 to 52%. In general, composite resins and adhesive systems showed no difference in clinical performance. Conclusion: Bulk fill composites usually have a lower polymerization shrinkage and shrinkage stress. Postoperative sensitivity is related to several factors. Therefore, to avoid such discomfort, all steps of restoration must be carefully performed.
Wobido AR, Cardoso IO, Reis BR, Machado AC, Soares PV. Composite resin in the last 10 years – literature review. Part 4: polymerization shrinkage and postoperative sensitivity. J Clin Dent Res. 2019 Sep-Dec;16(3):22-54.