[Prosthetics]  How should I restore this multiunit posterior implants?

Hello Docs. I hope all is well.
I have attached a radiograph where I placed three implants( 1 4.5 and two 5.0 ) in the upper left quadrant.Both posterior implants have ISQ of 82 and the one in position 24 has 76 values.
The patient really wants a screwed in fixed prosthetic. 
My concern with it is the implant to prosthetic length ratio. The crowns in this case would be as much as twice the length as the implants. What do you think. 
I was  thinking more on a bar held partial denture. Your thoughts please.
One more Q. Have you ever had an implant that the ISQ  would not give you a value. I could hear the humming sound but I could not get a value. let me know thanks

by Mark Kwon at Wed, Mar 18, 2015 9:38 PM

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Bernard Jin Replied at Sun, Mar 22, 2015 11:17 PM

Hi Dr. Who I'm in agreement with Drs. Kwon, Lui and Chong. All great ideas and proposals. About the smart peg ISQ - yes you are correct. Sometimes - esp. in the maxillary posterior - I do notice that the ISQ machine will emit 'sonar' pulses but it won't take a registration of the fixture. I believe this happens because of the density of the adjacent bone and the fact that there are stress-absorbing fixtures and sutures nearby; I'm thinking pterygoid plates, fissures, etc. When that happens, I generally perform a torque test with a graduated torque wrench and test the fixture at 35Ncm. If/when it passes, I proceed with the prosthetics. I realize it's a but ballsy and risky - but the best time to know if your fixture Osseointegrated is before you deliver the crown. Hope that helps.

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Ho-Young Chung Replied at Thu, Mar 19, 2015 12:29 AM

Hi Dr. Who, Nice placements and looks like bone has been maintained very well to the top of the first threads. Nice use of the smart membrane as well. Hard to tell on this PA but I'm assuming you did either an SA3 or SA4 for the 27 as well. I agree with a 3 unit implant bridge and a single for the back one. Open tray impressing copings (HiOssen ones are called fixture pick-up impression copings because the impression copings are picked up in the impression) are a must. I agree with Dr. Lui. Bite index will be helpful for SkyCad to mount the case. Dr. Kim has an OPR on this. You want to choose the bite index that is high as possible without actually touching the opposing teeth in MI. If there was only a single implant in quadrant 2, that is when I would do an implant-retained partial using a locator abutment. These work really well for retention and reduce the need for claps especially in the anterior region. Looks great Ho-Young

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Mark Kwon Replied at Wed, Mar 18, 2015 9:40 PM

Hello Dr. Who, Hard for me to tell what the crown to implant length ratio in the PA. If you have good parallrlism, You can go 3u 23-x-26 and individual single 27. Take it out of lateral excursion. If you want to screw retain all 3 fixtures, i would recommend placing straight MUA's, then take mua level impression. Ask Skycad (or your CADCAM lab of your choice) to fabricate screw retained zirconia bridge w titanium base to connect to mua's. This will ensure passive fit. Hope this helps, - mark