Occlusion for All on Four against Natural Teeth During Transitional Phase?

Research shows less longevity with this particular combination. So possible: bocortical stability, maximum a-p spread, osteotomes, longer integration time, no second molar occlusion. All stuff you already know. 5 implants: lose an implant but not the case??

Great question. There are a number of occlusal schemes that exist but I believe a balanced occlusion is ideal for immediate loaded prostheses. From a biomechanical standpoint, this is the way to minimize forces in any one particular area of the prosthesis at any one time. It is quite difficult to achieve a balanced occlusion. It takes time and patience to achieve it. Additionally, immediate prostheses are often fabricated using denture teeth and acrylic. I have found canine guidance leads to fracture or delamination of the canine denture tooth. Occlusion on only the anterior is the worst occlusion, in my humble opinion. We must remember that although implants are biological, they are first and foremost mechanical screws so always think about the mechanics when dealing with implants and occlusion.

It is challenging to get it right, but it's the right way to go. We usually recommend anterior guidance with very fast posterior disclusion to keep the patient from being able to put max forces on the anterior teeth. If the patient is a heavy bite then you will have to watch for more rapid deterioration of the posterior occlusal surfaces in the 3-4 year mark. This can lead to a ground-in anterior bite that will lead to breakage.

Have you thought of using Locators and fabricate an implant retained overdenture?

Hi Good question For upper jaw it is recommended to go for 6 implants with tilting the last distal implants. During temporary restoration stage go with balanced occlusion. Final t Restoration go with group function Thank you

In addition to other good comments and especially if this is a new protocol to you: 1. immediate load: cut posterior teeth back to the posterior temp cylinder-no cantilever during healing. Any cantilever will put too much sheer on angled implant and the cantilever will fracture leaving you and your patient immediately stressed and need a complete new conversion needed. 2. After cutting cantilever, you don't have many occlusal contacts, Point contact group function and patient on soft diet one month 3. Plastic against natural teeth: a full denture opposing natural teeth is never good but the denture Moves so this prevents breakage for a while. fix the denture to implants in same case and plastic/ti frame may fracture quickly if there is not excellent space for parts an materials . 4. 15mm rule: if you don't have 15 mm from occl/Incisal edge to implant platform, the acrylic cases are susceptible to fracture regardless of occlusal set up. Especially opposing natural teeth, start to offer better more predictable options as to number of implants and restorative materials. 5. AO4. Is not one size fits all. True AO4 treatment has very specific guidelines. If you want a real honest assessment of success vs failure call some larger labs in the country that specialize in AO4 talk to lab manager about the failed cases they are sent to bail Doctor out Sincerely. Leonard