“All Porcelain Restorations”-Occlusion on second molars
By: Dr. Neeraj Khanna
There are many clinical challenges in everyday practice that can create a lot of fr ustration for Dentists. One common challenge that occurs more often is the difficulty of fabricating a crown on a second molar. For example, your crown preparation has adequate reduction , and when your patient closes into maximum intercuspation, there is barely enough interocclusal space for you to fabricate a provisional. Why does this happen? What is the cause of this dilemma?
Before we answer these questions, most dentists will either continue to reduce the preparation or simply fabricate a very thin provisional. The crown restoration in these cases is usually “very high” in occlusion. The frustration continues as you spend a large amount of time adjusting the restoration in order to make the occlusion “fit”. The end result is a crown with no anatomy and is very thin resulting in fracturing of a restoration. Over time, the thin crown will be perforated and then you have another problem - no interocclusal space to work with. I have personally experienced this myself and did not understand why this was occurring until I decided to understand and study how dental occlusion really works.
Occlusion really starts with understanding joint (TMJ) position and how teeth articulate with each other when the joints are in their most stable position. Understanding this aspect alone will solve 95% of the frustrations encountered with restoring second molars. My suggestion for you is to learn and understand occlusion from a joint position, and start restoring teeth (especially second molars) when the occlusion is stable. Practicing dentistry this way will produce more predictable results, create more efficiency and decrease your frustrations. When preparing your next IPS e.max crown on a second molar, I hope you think about occlusion first.
Dr. Khanna grew up in Toronto, Canada where he attended the University of Toronto and completed his Bachelor of Science degree (1989). He then continued post graduate school at the University Of Detroit Mercy- School Of Dentistry and earned is D.D.S. degree (1993). Dr. Khanna has completed training at the prestigious DAWSON ACADEMY (St. Petersburg, FL). He has been faculty with the Dawson Academy since 2010, and is now a Senior Faculty member. His training at the Dawson Academy has inspired him to dedicate his practice to excellence in comprehensive restorative and aesthetic dentistry. Dr. Khanna’s philosophy involves treating every patient in the four aspects of complete dentistry.