Biomimetic Approach in Tooth Conservation and Fracture Resistance: A Short Descriptive Review of Current Biomaterials and Techniques

Background: New concepts such as biomimetic dentistry, minimally invasive approach, and the understanding of tooth biomechanics have changed the paradigm on how teeth need to be restored. The emergence of new biomaterials has allowed to improve bonding capacity, as well as the ability to reduce loading stress transmitted to the remaining tooth structure, making it possible to extend the life of a restoration and give the compromised tooth a second chance. To date, several studies have demonstrated the fracture resistance under uniaxial loading of restored Class II mesial-occlusal-distal (MOD) dental cavities in posterior teeth using different restorative biomaterials; however, many of those materials have not yet been compared with each other regarding fracture resistance. Objectives: A literature review was undertaken to revise current research focusing on the fracture resistance of MOD cavity preparations restored with different filling techniques, including microhybrid and nanohybrid composite resin, short discontinuous fiberglass reinforced composite resin, long continuous polyethylene fiber, fiberglass reinforced net, and the combination of these materials. Conclusion: This literature review offers information regarding currently used restorative biomaterials’ fracture resistance in restored MOD teeth. Most studies were conducted in vitro, demonstrating that fracture resistance under uniaxial load was higher in MOD cavity preparations restored with a combination of polyethylene fibers and composite resin (nanohybrid), followed by a combination of fiberglass and composite resin (nanohybrid). The reviewed information also revealed that the use of composite resin as a single material has the lowest fracture resistance and the highest percentage of catastrophic failures. Given the limited information regarding the combination of these biomaterials in a clinical setting it is suggested to perform controlled clinical trials by using the proposed combinations to demonstrate their clinical relevance and success ratio. Nonetheless, initial data suggests that a biomimetic restorative approach using biomaterials that connect and replace the missing tooth structure and redistribute biologically the loading stress may have a positive impact in terms of tooth preservation in MOD cavities.