Constructing 5 unit implant retained bridge on 2 implants: too long a span?

Place an implant at 9.

You may get some bleeding but the nasopalatine canal can also be grafted routinely. If your worried do it guided to avoid the canal. It sound be fine.

You may consider blade form implants. You will have to ramp down a little to get them started. You may have to expand the ridge a little to use blades or root forms. Remember to cover the osteotomy with OsteoGen after expansion. It would be nice to see radiographs and photographs of the area and patient in centric etc.

I will definitely place an additional fixture on site number 9 to secure my prosthesis from a bio mechanical viewpoint. I do understand the patient desire not to undergo bone grafting procedure on site 7 and 8 and therefore my secured and only solution in this case would be 3 fixtures on which is fitted a five unit bridge. The interesting questions here would be: Is an internal connection type of implant better option than a n external one? Is a cemented type of prosthesis better option than a screw type? What is the minimal dimensions of fixtures required both in length and width?

With the basic questions you need answered, is it in the patients best interest to have you place the implants?

I would ask myself a number of questions before deciding: 1) Is there a solid and stable posterior occlusion? 2) Is the anterior arch shape acutely ovoid or is it more gently rounded? 3) Are the proposed implants at least 11.5mm long? 4) Is the patient an "aggresive" chewer, bruxer, or generally use high masticatory forces? My personal concern would no be so much whether the bone would hold up, which it should with longer implants, but rather would the abutment screws withstand the constant torqueing because of the curved shape of the bridge. The patient could be warned of having to replace abutment screws from time to time.

The long span over an arch form will provide for high cantilever forces over the central incisor areas. Not a good idea (see Misch et al). I would always place three implants in this instance. Ridge split or bone graft. Avoid the NP canal if possible as this reduces osseointegration in this part of the implant and can lead to failure. Mesial torquing on the implants is better than distal but unless incisal forces are very light I would go for the increased mechanics of three implants in this situation.

Any dental reconstruction, whether tooth or implant borne needs to by engineered for longevity. With that in mind, you absolutely need a third implant. I disagree with a blade implant, they are not proven so don't expose your patient to something that you probably wouldn't put into your own mouth. I tell my patients they have two choices, a removable prosthesis (yes, conventional dentistry is still viable) or we do implants the right way; three implants, ideally with a bone graft to get an implant in #8 but otherwise #9. I'm not sure why anyone would recommend a blade implant since they haven't really been used for many years. Make sure your treatment is based on sound mechanical and biological principles. Don't have a long span. Make sure you use proven implant systems. Remember, do only to your patients what you would do on your family member. Your patients trust you so when in doubt, overengineer your implant treatment or go to conventional removable prosthodontics and don't do implants at all.

Dr Johnson, For your information blade implants have been reclassified to the same status as root forms by the FDA. I have blade cases in uncomplicated function for over 18 years. I will say that they are not for every doctor. The doctor needs new skills and has to understand the concepts of immediate and progressive loading. I placed 10 blades last week on four patients. I do agree to over engineer the case. Removable is an option.

Yes, you're right, I have heard blades have been reclassified. Do you know of any research that shows long term results? I'm still not convinced they are as successful as root forms. I'm still remembering the 50% success rates of the old ramus frames, subs and blades before root form implants came to market. Are these new blades two piece? what research was presented to the FDA to reclassify them? If you have blades in function for over 18 years, how many failed over the same time? I have restored staple implants, subperiosteal implants and ramus frames which have been successful but they're the happy 50% not the unhappy 50% As you can tell, I've been at the implant game a long time and the older I get the more failures I see so I get more and more conservative. Please let the readers know your success rate and I'd love to see the info. that shows long term success. Thanks for your input! M

I just sent a reply to Dr. Hughes. You refused to post it. Is this website run by Dr. Hughes? My comments were not inflammatory or in any way demeaning. I simply asked for information regarding research on blades. Please respond as to why osseonews thought my post was inappropriate. There should be shared information between parties and not filtering by one side if they don't agree with the post. There should be dissemination of information bilaterally so that posters can be questioned as to the rationale behind their posts. Otherwise misinformation can too easily be spread.

Dr Johnson, You maw want to do an online search as per the FDA hearing of this last July. The FDA did literature searches for blade form implants. I was not familiar with the data from the FDA. In my practice, I have nice results. I was trained by Drs Linkow and Roberts. I think a lot of the failures of others resulted from several factors. Such as not fixating the blade ASAP resulting in fibro- osseousintegration, overloading, placing the blades to buccal and using poorly designed blades that do not transmit forces well and some were to flimsy. Taking advantage of new surface tech, current concepts of progressive loading and immediate loading, staying away from poorly compliant patients etc improves results. The 50% failure rates that you refer to are doubtful. The success rates are much higher with subs, ramus frames and blades. You have to keep in mind that there are learning curves and these modalities require that the doc understands a lot more and has a different set of skills. There are problems with root forms. Just look at some of the post on this blog! If there were not any problems there would not be any postings! How many times do abutments come lose? The ubiquitous implant out of alignment. The issues with bone grafting, periimplantitis etc. the list goes on. There was a post about a root form implant in a max cuspid site. This can be a tricky area with any type of implant. The poster had the honesty to post the problem with dehiscence at the apex. All this stuff works and yes there are some failures. These issues are situational. When you get down to it. We have to ask , just why did a patient lose their teeth? And what now gave them this come to Jesus moment? I'm not being flip with you. All these modalities work under the right conditions. They fail for common reasons.

When it comes to the treatment of the atrophic posterior mandible, the use of certain blades (used correctly) go along way to uncomplicate and reduce the cost of treatment. The ramus blade from Pacific Implants, Inc. are fantastic for the Mandibular distal extension. The preanfled STR and hockey stick design implants are great for the maxilla. These two designs for the post maxilla can reduce the need for sinus lifts by 90%. There is up to a 20% failure rate with root forms in the grafted sinus. These implants are not placed into grafted bone!

Thank you for your more in depth info. on blades. I agree there's situations that are difficult with conventional root forms so alternative implant systems may be a solution to bone grafting. I'll look into the companies you mentioned. I will also do a lit. search to see what is out there. I don't have a 20% failure rate in grafted sinuses so, like your blade success, success rates in more complicated implant surgical situations are extremely dependent on the skill and experience of the surgeon.

FDA approval simply means they are safe to put in the alveolar bone. It says nothing about efficacy. I personally need more information to help out in this case. Bv

Dr Johnson, You are correct, fibroosseous integration is not the interface of choice. An osseointegration is essential for all Endosseous implants ( blades, root forms, disc, 3D). Sorry that I did not answer this sooner!