I was wondering if placing multiunit abutments on all bar overdenture cases makes for more predicatable results (passive fit of bars) vs having bars fabricated at implant level?
Also are there any concerns with placing angled implants with MUA's on removabale bar overdenture cases? I was thinking this way the patient could upgrade to a fixed prosthetic at a later time.
by Jessey Minhas at Wed, Jul 16, 2014 5:45 PM
1624 Views | 5 Replies
Likes : 0
Mark Kwon Replied at Thu, Jul 17, 2014 6:34 PM
Much easier to put-in and take out bar on MUA then directly over fuxture level , especially during try-in stage. Pt dont apprecate bar "pinching" the gum during the fitting process.
Likes : 0
Jessey Minhas Replied at Thu, Jul 17, 2014 6:05 PM
Great, thanks for the input! All 3 of your comments were really helpful. Jessey
Likes : 0
Bernard Jin Replied at Thu, Jul 17, 2014 2:10 PM
Hi Jessey I agree with both HY and Dr. Kim. MUAs can save your bacon when it comes to achieving good draw and passivity for the final prosthesis. I can personally vouch that trying to keep everything fixture level can be difficult at times - especially when you don't have good draw. With respect to the idea of keeping your options open for the patient (ie. having a locator retained vs. non-removable implant bridge), the angled implant placements could potentially result in you eating up your vertical dimension in the posterior. It's not to say that it cannot be done - but that if your patient has very limited vertical space in the posterior, placing an angled MUA will diminish the space. This, in turn, will compromise your final removable prosthesis' volume for the acrylic and locator housing, etc. If the vertical dimension is very large, than you've got nothing to lose with your proposal. Best wishes!
Likes : 0
Ho-Young Chung Replied at Thu, Jul 17, 2014 5:34 AM
Hi Jessey, Dr. Kim's the expert on MUAs. :) I go fixture level if the implants are parallel. If they are not relatively parallel then it makes your life easier to go abutment level. Cost goes up but headaches go down for the reasons that Dr. Kim outlined. I would also ask your denturist (if you are working with one) how much space she needs and then determine whether you have room for an abutment plus bar plus acrylic. I'm assuming the patient will be getting a milled locator bar. If that's the case then yes, the patient can go fixed at a later time. However, she will still need a new wrap-around bar rather than a milled locator bar. In other words, I think going MUA will not be a factor in whether the patient can have fixed in the future. Hope that helps a bit. Ho-Young
Likes : 0
Danielle S. Kim Replied at Thu, Jul 17, 2014 3:52 AM
Hi Jessey, MUA is a special prosthetic item that provides many advantages (vs fixture level) because of its unique design -- i.e. dome shaped. It really makes your job easier and predictable. 1. You can choose MUAs with different height to bring the margins to the tissue level if implants are placed deep. You may avoid giving l.a. every time. 2. It facilitates certain prosthetic procedures -- taking impression, verification of master model and bar. 3. It can also work as a buffer if perfect passivity is not achieved from minor distortion/discrepancy. Stress induced won't be directly transmitted to the fixture. 4. You can use angled MUAs (17 or 30 deg) to correct the path of insertion when implants are too tilted/angled from each other. Unfortunately MUA is not an option when space is limited. For overdenture cases, you need to consider the height of MUA which will take up the space in addition to the minimum thickness of bar&acrylic required for strength. Hope this helps, Danielle