Shadow Day with Dr. Shelley and Dr. Fellner

Today I shadowed at Arrowhead Lakes Dentistry, which is conveniently right down the road from Midwestern University. I began the day observing Dr. Shelley's patients. He had a variety of different appointments scheduled such as consultations, cavity fillings, crown work and routine checkups. The first patient need cavities filled on the left mandibular cuspid (for reference I included a diagram with corresponding names below). Dr. Shelley administered two shots to numb the left side of the patient's mouth before beginning removing the decay from the tooth. Then Dr. Shelley primed the surface, where the decay used to be, and added a bonding agent before filling the space with composite resin. The resin was then light cured in order to harden. Dr. Shelley smoothed the surface to the point where the patient felt no rough surfaces. The next patient had a failed crown on the left mandibular 3rd molar. Usually this means the integrity of the crown or the cement was compromised rather than the natural tooth itself allowing for an easy re-cementation procedure to permanently fix the problem. However, this patient only had a minimal amount of natural tooth left because the rest was still cemented inside the crown. Eventually the patient will need a root canal, but due to the patient's current dental condition Dr. Shelley decided it would be more beneficial for the patient to have the crown re-cemented even though the failure probability is high. He hopes it will provide some function between now and the scheduled appointment for the root canal, which is the permanent solution. The really interesting procedure I witnessed today was with Dr. Fellner because he used the CAD/CAM technology to fit a crown. In a later post I will go into a more in depth description on how the CAD/CAM works, but essentially it allows for the dentist to upload a three-dimensional diagram of the patient's mouth onto a computer equipped with software that can fit a crown for the problem tooth. The doctor can then make additional adjustment to the computer's suggestion. To get the actual crown the three-dimensional image is sent to the milling machine that takes a block of zirconia or lithium disilicate and shapes it to match the exact image created on the computer. After manually fitting the crown and making any additional adjustment it is baked in an oven to reach its maximum strength, then cemented into the patient's mouth. Typically, a crown fitting would take about a week and two different appointments because the initial mold would have to be taken and sent to a lab that has the capacities to make the crown, while the dentist fit the patient with a temporary crown in the mean time, then once the permanent crown comes in the dentist must remove the temporary crown and cement the permanent one. This is why the CAD/CAM technology is so fantastic! It can all be completed in one appointment with less moving parts. Overall, it was a really fun day and I learned so much about CAD/CAM technology in private practice.

Diagram of the Human Mouth