Failed Implant: At What Point Is This a Consideration?

Any degree of clinically noticiable mobility is not a good indication. This means that fiberous area is developing between the recently placed fixture and the bone as a result of inflammation or trauma during surgery. better to remove now verses waiting and lettign more bone be lost. currette the site and graft and allow 6-8 weeks to heal before placing another fixture.

You mention that you placed the implant with standard surgical protocols. If that is the case, why did you use antibiotics if there was no infection present? If there was infection present, why did you place the implant? Standard of care dictates that antibiotics should be used where indicated and NOT prophylactically for routine elective procedures.Routine elective procedures should not be performed where there is active infection present. Assuming there was no infection present and the surgery healed uneventfully, how do you know whether the implant is mobile as standard protocol dictates a 2 stage approach and the implant should not be exposed. If this is the case, how do you know the implant is mobile? If the implant is exposed, therein may be you problem.

Dr.GJ Berne, It is standard protocol to prescribe antibiotics after a routine placement of an implant. And 2-stage approach is not the sole standard protocol - the need for location sensitive soft/hard tissue preservation calls for various 'standard protocols'. Dr.B, implant failures are a regular part of implant dentistry (ie. no one has 100% success). If you have implant mobility post-6 weeks, I would 'unscrew/finger-exo' the implant, degranulate and place a wider and/or longer implant immediately.

REmove, curette and reinsert in 6-8 weeks. It will take the second time - bone will be soft when it goes in

Dr Kong, With all due respect, the standard implant placement protocol is a 2 stage procedure. That doesn't mean there aren't other protocols, such as a 1 stage, or immediate load protocol. When you depart from the standard protocol(ie 2 stage procedure) the the risk factor increases. Certainly in my hands the 2 stage protocol is used most frequently and failure to integrate using this protocol is rare indeed. When a 1 stage protocol is used then there is an increased risk for failure because of a number of additional factors, such as an increased likelihood of infection and trauma during the healing phase. Certainly I do not routinely use antibiotics and my infection rate is as low as anyone's. I do use a sterile procedure,however, with care to start with a clean mouth (no active infection), care with cleaning adjacent appendages such as beards and moustaches (very significant sources of infection) and careful rinsing with Chlorhexidine mouthrinse prior to surgery. Antibiotics should NEVER be a substitute for good surgical practice. Anyone who uses a protocol which advocates routine prophylactic use of antibiotics for elective surgical procedures is playing with fire. Just have a look at the problems that antibiotic resistant microbes cause in hospitals and you might appreciate what I am saying.

Dear sirs -- i quote these papers to show the efffectiveness of pre-operative antibiotics. i always give antibiotic cover before placing an implant. Dent CD, Olson JW, Farish SE, Bellome J, Casino AJ, Morris HF et al. The influence of preoperative antibiotics on success of endosseous implants up to and including stage II surgery: a study of 2,641 implants. J Oral Maxillofac Surg. 1997;55:19-24. Laskin DM, Dent CD, Morris HF, Ochi S, Olson JW. The influence of preoperative antibiotics on success of endosseous implants at 36 months. Ann Periodontol. 2000;5:166- 74.

If the implant shows mobility, it is a failure. Remove it and try to remove all soft tissue and place a larger implant. Or, remove the failed implant and wait 6 weeks and place another implant. Third possible solution is to remove the failed implant, regenerate the bone, wait 3 months and place another implant. The clinician must make the decision at the time of surgery. But of all things, remove the mobile implant, it is a failure. True, there are no 100%'s.

This clinical manifestation is certainly an implant failure. But it is unlikely a result of infection given the combination of antibiotics used. First, what type of implant was used? Certain implant architectures are more prone to this type of early failure. There is an initial catabolic phase that most implants go through where, for the first 2-3 weeks, the bone to implant contact is significantly weaker than at the time of placement. If you have a highly compressive implant design, there can be excessive bone microfracture which accelerates this phenomenon. Second,you describe the use of a COX1/2 anti-inflammatory. It has been demonstrated the excessive use of anti-inflammatories post-operatively inhibits the production of prostoglandins, a vital initiator of osteoblast metabolism. Third, was this a grafted site. If so, what is the percentage of vital bone in the site? If a non-resorbable graft (i.e. BioOss) was used, there will be a critically low percentage of vital bone cells for integration. Last, you describe the use of a 4.2mm implant in a mandibular molar region; a very narrow diameter for this site. Was the ridge narrow bucco-lingually? If so, there is a diminished zone of medullary bone. If the implant is in contact with cortical bone on both plates, there is a dramatic increase in implant failure rates as there is an insufficient percentage of bone cells in cortical bone for osseointegration. RJM

Implant failures can be caused by a wide spectrum of reasons and infection is one of them. Dr. B, have a few questions to ask... 1)Was the patient medically fit with no systemic conditions that contraindicate implant therapy? 2)Does the patient have any periodontal disease... which leads to ask if the molar u replaced with an implant was extracted due to caries of periodontal disease.? 3)Highly motivated patient with no history of contraindicating medications and good oral hygiene? 4)Is the patient a smoker? 5) Was there a removable prosthesis given immediately after the implant surgery?(trauma to underlying soft tissue) The failure you described is classified as an early failure. Most often the failure occurs due to any of the above violations, poor seating of the cover screw (harbor micro-organism) poor surgical procedure and finally poor sterilization protocol. A clinically mobile implant is considered as a "failed implant". Do retrospectively analyze and pin point on the cause, this will help in avoiding it in the future. In case you do, please comment on this.Good luck.

The cause of mobility different if you used one stage dental implant or 2 stages dental implant. In case of one stage implant the cause of mobility was premature loading before the osseointgration occur and not infection. In case of 2 stages implant the cause of mobility was physical trauma at time of operation,may be over speed or over pressur, so you get primary stability at first and with the time bone resorption occur and then replaced by fibrous tissue. In both possibilities you need to remove the dental implant and then either augment the site of implant with bone graft and you wait 6 months, or you can do new drilling for the previous implant site and insert new implant with diameter and length according to new drilling. Please NEVER insert new implant without new drilling because you end with new failure and mobility impant

sounds like you had and immidiate loaded implant....(you din't specified)Since you said, that initially the stability was good but six weeks later, you noticed increased mobility......is evident that the implant was exposed to the oral environtment...and by that, I mean to occlusal forces, etc, ect....which may have had an impact on integration...If not it sounds like tissue invasion of your site....

In those papers that recommended preoperative antibiotics, what did they recommend?

According to Esposito's meta-analysis 2008 there is evidence for less implant failures if 2gr of Amocillin are given 1 hr before surgery "There is some evidence suggesting that 2 g of amoxicillin given orally 1 hour preoperatively significantly reduce failures of dental implants placed in ordinary conditions. It remains unclear whether postoperative antibiotics are beneficial, and which is the most effective antibiotic. It might be recommendable to suggest the use of one dose of prophylactic antibiotics prior to dental implant" placement.

DR B, 1. IT IS NOT CLEAR WHETHER 1 OR 2 STAGE? 2. WHEN IT IS LOADED