It has been over 40 years since direct posterior composite resins were introduced as an alternative to metallic restorations, most specifically amalgams. During that time, they have been met with doubt and skepticism, which was borne out by myriad shortcomings such as poor wear resistance, microleakage, bodily fracture, marginal breakdown, recurrent decay, post-operative sensitivity, inadequate interproximal contacts and contours, color degradation and inability to polish or maintain polish. Couple these physical and mechanical failings with erroneous placement techniques and lack of knowledge as to how these materials would respond in the posterior segment of the mouth, and one can readily see the potential for success by the early adapters of composites was greatly challenged.
Today it would be hard to imagine being able to meet the restorative demands of our patients without the use of resin-based materials. Specifically, direct composites offer the dental professional one of the most cost-effective methods to restore a patient’s dentition in an aesthetically pleasing manner. Although the profession has managed to conquer many of the shortcomings, several of these issues still remain a challenge to us in placing posterior composites: Obtaining a good marginal seal, the role of bases and liners, creating tight interproximal contacts and the dreaded “post-operative” sensitivity just to name a few.
It is my hope to explore some of these issues to combine science, materials and practicality to stimulate some thoughts as we search for solutions to these dilemmas.
Before we even pick up a handpiece, let’s start by examining the tooth that requires restorative treatment. If we create a “mental checklist” to evaluate the situation, perhaps the issue of post-op sensitivity would be diminished. Ask yourself the following questions:
What is the current condition of the tooth? Does it have a large existing restoration that is failing? Recurrent decay? Visible cuspal cracks? Is it sensitive to hot and/or cold temperatures or chewing? A tooth that is already displaying one or more of these symptoms may or may not have these symptoms rectified with a direct composite – no matter how well it is placed! Addressing the issue of post-operative sensitivity begins at the beginning, and taking the time to evaluate the pre-op condition of the tooth and discuss these issues with the patient before moving forward with treatment might help avoid second-guessing later on.
As we continue to evaluate the many facets of posterior composites, we will try to build a plan or “recipe for success” that will make their use predictable and efficient for our practices. One of the key considerations in our “recipe” would be how to choose an adhesive system between the etch-and-rinse, self-etch and the new universal bonding agents. We will explore that topic next time!