It has been a very cold winter in Toronto this year and many people in my family have been hit with a flu and so my household has not been very festive this holiday season. In any case, I wish everyone had a great holiday and wish all a great 2018.
As a prosthodontist, it is not unusual that some of my dental colleagues would ask me for guidance in managing their prosthetic cases. I find that many of their questions are quite technical. In fact, it made me realize how much knowledge I had taken for granted. So in this post, I decide to share with you my thinking process that I go through when I restore an implant supported case. It is my hope that my approach will help some of my colleagues avoids nightmares and problems they had in the past for their own implant supported restorations.
So here are some of my advices:
1/Pick a lab that is knowledgeable in implant restoration. I know this is common sense but one of my dental colleagues is having a lot of trouble with her case. In trying to figure out what went wrong, the lab appears to have ordered the totally wrong components for the case. This is something a dentist should not have to worry about but when the lab had completely ordered the wrong components for the cases and didn’t even acknowledge it, I have no confidence in what they do at all. Beware.
2/Avoid making any prosthetic decision until you have taken a fixture level implant impression. The implant world is full of different restorative components to be used for your case. There are prefabricated stock abutments you can use. There are multi-unit abutments that can correct the angulation of your implants for restorative purpose. They are engaging and non-engaging components to be used. The possibilities are endless for many different clinical scenarios. For me, I keep things simple and never make a restorative decision on my implant restorative case until the final implant impression has been taken. All my cases start with a fixture level implant impression. As a result, I only have one type of impression coping: open tray engaging implant impression coping.
3/Personally, I only use open tray impression technique with a custom tray. In the past, as a resident, when I used to pour up all my impressions, I would switch between open tray and closed tray technique depending on the components available. But after being in private practice of many years, I noticed that, whenever I used some readily available closed tray components provided by my colleagues, I had more errors in the model. To me, that is a human error that I didn’t have when I connected all my components and poured up my own impression before. When it comes to closed tray components, it is my suspicion that sometimes the technician may not have repositioned closed tray impression component back in the impression completely and caused an error in the occlusal gingival positioning of the implant. For a single tooth restoration, it may have translated into more occlusal adjustment or proximal contacts that are not quite as good. So it’s possible you can get away with this type of error by making some chairside adjustments. But when you start doing multiple unit cases, this can translate into a bigger problem that takes a lot more work to correct. So in my implant restorative cases, I always order open tray fixture level implant engaging impression copings. In this way, there is less chance that a human error can screw up my impression. And once the impression has been poured up, the case can be analyzed outside the mouth and the restorative design can be made without being committed to any ordered components. To me, this simplifies the decision on what to order, simplifies the inventory need for your office and takes the stress out of your hand to decide what you need for your every case.
I hope you find these tips helpful in your implant cases.
Please check out my other posts too.