Welcome to the lecture on implant supported provisional restorations. In this series, we will discuss about the significance of placing provisional restorations in implant dentistry in daily practice. First of all, what is the definition? We know from dental school that a provisional restoration can be fabricated of composite or acrylic material. The provisional restorations on implants can be supported by a plastic or a metal abutment. These restorations are serving as temporary solutions until the implant has achieved osseointegration. Why are provisional restorations important? The ability to accomplish a successful implant placement followed by an implant-supported restoration in the aesthetic area relies on the knowledge of critical surgical and prosthetic parameters. Creating a favourable aesthetic result in the three-dimensional peri-implant and soft tissue surroundings is not only dependent on bone reconstruction techniques and implant positioning, but also highly dependent on a well-performed tooth-like restoration. In this context, fabricating a precise temporary crown, also called provisional, becomes an extremely important step in the contemporary implant-restorative dentistry where patients are demanding more and more aesthetic results in all phases of their treatment. And we're also trying to minimize the number of surgical procedures performed. When can we place them? This moment relies on the implant placement. Ideally, we would like to place them simultaneously with the implant. In this way, we minimize the number of surgical procedures the patient will go through. Sometimes if the implant doesn't have appropriate primary stability, we need to wait until the implant is osseointegrated in order not to compromise this process. Some authors prefer to condition the soft tissue before the implant placement with the use of a pontic, especially if that particular area received a bone regeneration procedure. There are different techniques and materials that we have to take into consideration. Choosing the appropriate combination of materials and methods for the fabrication of a provisional restoration with high quality is crucial to guide the tissue and predict the final aesthetics. A precise technique provides restoration that fulfill the peri-implant tissue and aesthetic requirements needed to achieve an excellent final restoration. We can have screw retained or cement retained provisional restoration. For the screw retained ones, the type of abutment can be either plastic or metal. For the crown, we can either use a prefabricated shell that we can fill in with acrylic, we can duplicate a wax up and have an acrylic shell done in the lab, or we can use a denture tooth that we can adopt and reline with acrylic. For this presentation, we will use the last technique, the denture tooth technique, as this provides higher aesthetic results. There are some key principles that we need to take into consideration. Implant stability, measured by ISQ. This is important because an implant that is spinning and will receive a provisional restoration immediately has high chances of failure. Occlusion. This can also affect the osseointegration of the implant as if the forces are high can produce micro-movements that later on will jeopardize the osseointegration. Ideally, we release the provisional restoration and is out of any occlusion forces in all lateral and protrusion movements. Space maintenance. For an area that will receive the implants later on, we do know that there is a risk for malposition of the teeth due to tooth migration or extrusion. Provisional restoration can be a good solution to help maintain the space until the final restoration is in place. Stability of the soft tissue. Dr Chu and Dr Tarnow worked extensively on providing more information regarding the soft tissue stability during various moments of connecting the implant with the provisional restoration, specifically, looking at the papilla preservation. Healing time - soft tissue conditioning. For tissue re-modeling, provisional implant crowns should be used for approximately three months prior to the final restorative procedure. This can vary based on the tissue biotype of the patients. Interdisciplinary planning. The planning of such a procedure should be done interdisciplinary, taking into account the position of the final prosthesis and the location of the implant placement. Don't hesitate to ask a prosthodontist colleague for any questions. Patient compliance. I always tell my patient, "This is team-work.” I will try my best to give you the best treatment, but please take care of it at home and follow all the post-operative instructions. Let's review together a clinical case. We can notice on this slide, the edentulous area - maxillary central incisor” is missing and is at the moment restored with a removable partial denture, also called ‘the flipper”. A CBCT was exposed, and in order to evaluate the ridge morphology and digitally plan the implant. This slide identifies the need for bone augmentation during the implant placement. This slide identify basic steps of the procedure. Flap elevation, implant placement, adding bone graft and membrane. For this particular case, we used a collagen membrane because it will impede the invagination of the epithelial cells and also provide a better quality of the regenerated bone. Primary closure, also as you can see, very important. Since the patient needed a fixed restoration on the adjacent tooth, we used that as an asset to start soft tissue re-modeling around the implant area. You can see that we reinforced the provisional bridge using a wire for the pontic side. We made sure to create a convex profile condition the inter-proximal papilla. Implant uncovery - minimal exposure, and then replacing the cover screw with a healing abutment. Starting to prepare the provisional, we place the temporary abutment, we expose a radiograph, make sure it's seated completely. We adjust the abutment based on the height available and then we're starting to prepare the veneer of the denture tooth. We reline it with acrylic and then we make sure we respect critical and subcritical contours, concepts that were presented by Dr. Su and Dr. Weisgold. As mentioned earlier, polishing is very important, and leave some space for soft tissue to crawl and fill in the space left. This is a direct comparison between before and after treatment, and you can appreciate the amount of soft tissue conditioning obtained with the use of provisional restorations. This slide identifies a final implant-supported prosthesis. There are some future thoughts that we might want to consider. The research has evolved in a manner that more and more studies that take into consideration patient experiences and expectations are now valued. The topic of patient centred outcome research will certainly look into ways to evaluate the aesthetics achieved with provisional restorations. In order to facilitate an excellent aesthetic outcome, interdisciplinary collaboration should be highly considered as part of daily practice activities. That's all we wanted to discuss about the provisional restorations in implant dentistry. Thank you for your attention.
