The effect of preheating resin composites on surface hardness: a systematic review and meta-analysis
- Author:
Ali A ELKAFFAS
1
;
Radwa I ELTOUKHY
;
Salwa A ELNEGOLY
;
Salah H MAHMOUD
Author Information
- Publication Type:Meta-Analysis
- Keywords: Composite temperature; Meta-analysis; Microhardness; Microhybrid; Preheated composite; Systematic review
- MeSH: Hardness; In Vitro Techniques
- From:Restorative Dentistry & Endodontics 2019;44(4):e41-
- CountryRepublic of Korea
- Language:English
- Abstract: OBJECTIVES: This paper presents a systematic review and meta-analysis of the effect of preheating on the hardness of nanofilled, nanoceramic, nanohybrid, and microhybrid resin composites. MATERIALS AND METHODS: An electronic search of papers on MEDLINE/PubMed, ScienceDirect, and EBSCOhost was performed. Only in vitro studies were included. Non-English studies, case reports, clinical trials, and review articles were excluded. A meta-analysis of the reviewed studies was conducted to quantify differences in the microhardness of the Z250 microhybrid resin composite using the Comprehensive Meta-Analysis software. RESULTS: Only 13 studies met the inclusion criteria for this systematic review. The meta-analysis showed that there were significant differences between the non-preheated and preheated modes for both the top and bottom surfaces of the specimens (p < 0.05). The microhardness of the Z250 resin composite on the top surface in the preheated mode (78.1 ± 2.9) was higher than in the non-preheated mode (67.4 ± 4.0; p < 0.001). Moreover, the microhardness of the Z250 resin composite on the bottom surface in the preheated mode (71.8 ± 3.8) was higher than in the non-preheated mode (57.5 ± 5.7, p < 0.001). CONCLUSIONS: Although the results reported in the reviewed studies showed great variability, sufficient scientific evidence was found to support the hypothesis that preheating can improve the hardness of resin composites.
