This case was completed a few years ago. I learned a lot while doing this case. I learned even more following up on this case years later. When this patient came to me, she had a lot of issues. To name a few, she had an occlusal problem with a large CR/MIP discrepancy, a set of ill-fitting cast RPDs, and the teeth were just in the wrong place in the mouth.
Her chief concern was to improve the aesthetics of her smile. And she was not interested in having implants.
She was also a very active person in the community…always in a hurry and we talked about her treatment options several times…and finally we started working on the maxilla.
But before I can work on that, I had to get her a new transitional lower acrylic partial denture and performed some selective occlusal grinding on her mandibular teeth. This was to decrease the amount of CR/MIP discrepancy, an effort to start deprogramming her to get her in a more favourable jaw relationship. The existing lower cast RPD was not fitting well at all and at the time we haven’t finalized the treatment option for that arch but needed to have something to stabilize her occlusion, to replace her missing mandibular teeth, while I was working on the maxilla.
After much discussion, the patient and I decided to give her a fixed removable solution for the maxilla: a fixed solution to splint all the remaining anterior teeth, and a removable solution to replace her posterior teeth. To me, it solved her many issues. If you look at her maxilla, she had many lone standing teeth, which were not quite spaced ideally in the arch to have a pleasing aesthetic appearance. Minor re-contouring would be needed and a uniform full coverage of these abutment teeth with a fixed partial denture would provide the much needed aesthetic improvement for the patient.
But there was another reason why I decided to design this bridge the way I did. This FPD also eliminated the modification spaces this case may have had when it was time to design the cast RPD. By having a solid FPD that closed all the anterior modification spaces, the cast RPD becomes a very simple tooth supported RPD with favourable biomechanics. The fulcrum lines all work with one another and the elimination of modification spaces also eliminated other potential fulcrum lines that may have worked against the potential RPD movement.
After seeing how this patient could adapt to her poor-fitting cast RPDs, I knew she will adapt to the fixed removable solution I designed for her. And I was right. She was fine with the bridge and the cast partial denture. And she loves the new smile.
Now when it was time to work on the mandibular arch, I actually thought of removing all her mandibular teeth and to consider implant supported prosthesis. But she was not interested in any extensive surgery and wants to have a similar type of solution for the mandibular arch.
Her clinical crowns were not great abutments but she insisted on having a similar prosthetic solution. I told her that I was worried that the fixed removable solution would not have a great long term success. I was worried she will end up losing these teeth few years later. She told me she was willing to take that risk.
So I ended up also splinting the anterior abutment with a FPD and providing her a Kennedy Class I RPD. Remembering that she had a large MIP/CR discrepancy at the beginning, I was naturally worried that if I didn’t develop the anterior guidance properly, she may be at risk of porcelain fracture. While working on the mandibular arch, I was able to witness how she went from constantly protruding forward, a habit she got used to in order to adapt to her ill-fitting cast RPDs, to slowly someone who learned to close repeatedly in the position that I developed for her which I believed to be a more favorable position for her joints.. It was a transformation that allowed me to understanding the importance of occlusion…..
And to finish her off with a Kennedy Class I RPD, I told her that the denture will not be as stable as the maxillary one. But contrary to that, the cast RPD was really stable and the built in cingulum ledge in the FPD provided the additional support and resistance to anterior posterior rotation. This was also something I did not expect.
This case had been in completion for a few years now. The outcome was actually much better than I anticipated. Time will tell how this case will develop. But this was the one case that exceeded my expectation. The patient was able to eat corn on the cob. There hasn’t been any porcelain fracture at all and both dentures are still in very good condition. And most impressively to me was that she closes so predictably well without any deviation which was what I was most proud of on this case.
I hope by sharing my thought process in tackling this prosthetic case, you will gain a better understanding of prosthetic dentistry. Thank you for reading.
