Dear friends, thank you for staying with us during Module 4 of our course! This week was a very important week and it is the time when all the pieces of the puzzle start to fall in place. Once you master the principles of implant prosthodontics and rehabilitation, it is then when everything else makes more sense, from diagnosis to patient selection, and the planning of surgeries. As before, we had many interesting discussions this week as well. Much of the discussions evolved around the topics of prosthesis retention and different types of cement retention or screw retention were proposed for our patients. As you have realized by now, there is not absolute right or wrong in this case. The angle of the implant placement is a critical determinant for whether we will be able to use screw retention or not. Nevertheless, in many cases we actually have the option to use both screw retained or cemented reconstructions. In these cases, the selection should be done on an individual basis and there are many factors that we have to take in consideration, such as retrievability of the prosthesis, the available prosthetic space and its characteristics, the ideal emergence profile, aesthetic needs of the patient, and also cost related factors. As some people also discussed, the dilemma between screw retained or cemented prosthesis is not always absolute. At times, we can also use unconventional technological solutions which allow screw retained crowns to be placed even on implants with unfavourable angles of placement. An example of such a solution at the abutment level is the angled screw channel, where a modification of the abutment screw and the screwdriver allows us to place the crown on the implant with an angle as much as 25 degrees. At the implant level, another solution could be the co-axis implant, an implant where the prosthetic platform is actually at an angle with the axis of the screw. This way, a conventional screw retained crown can be placed, even if the body of the implant is at an unfavourable angle. To our patients now, most discussions with regards to Justin and Gina evolved around the temporary crowns. I think most of us agree that temporary implant crowns would be necessary for these two patients. By conditioning the soft tissues with the help of the temporary crowns, we can actually achieve the optimal emergence profile and aesthetics for these two patients and then follow up with permanent crowns. Some debated whether the temporary crowns would be best made at the chair side or at the dental lab. I think it's important to realize that the basic principles and the design of the temporaries are the same, regardless if they are made at the chair side or at the dental lab. Individual factors such as time, costs, and needs for aesthetics might influence our decision to make them chair side or delegate this to the dental lab. Finally, it was agreed that Mary, on the other hand, wouldn't require any temporary restoration on her implants. Instead, some discussion evolved around whether to place single crowns everywhere or splint the crowns where possible. I think today splinting of implant crowns is not necessary, apart maybe from few exceptional cases of compromised bone, such as for example, implant crowns in the posterior maxilla in case of excessive sinus elevation procedures. Much of the osseointegration is taking place in the regenerated bone, while implants in the posterior maxilla are bearing significant load. In such cases, one could consider splinting the implant crowns, aiming for a better distribution of the occlusal load to the bone. In cases, however, like Mary, where implants are placed in native bone, splinting of the implant crowns would not offer any advantage, while on the contrary, it could hinder efficient oral hygiene. Coming to the end of Module 4, you should now have a comprehensive understanding of all the skills, knowledge, and competencies that are required to design and execute successful implant treatments. And maybe we left the best for last, that this, how to ensure that your successful treatments will stay successful for a long time, and that your happy patients will carry on with the smile you recreated for them for the rest of their lives. This, we will discuss next week, in the last part of our course, which is about living with dental implants and also living with dental implant patients. Thank you very much.
