Long-term implant maintenance and tissue management
A report from Europerio 7 June 2012 by Juliette Reeves
The Messe Wien Exhibition and Conference Centre opened its doors on a beautiful sunny morning in Vienna last June to host the 7th Conference of the European Federation of Periodontology.
One of the key sessions regarding current understandings of peri-implant diseases took place on the Friday afternoon program.
A joint symposium which included presentations from Professor Mariano Sanz and Professor Stefan Renvert looked at risk factors and treatment modalities associated with peri-implant diseases.
Professor Mario Sanz began his presentation by highlighting the fact that there are more than 145 implant manufacturers worldwide providing 600 different implant systems.
Only six of these systems are supported with more than 20 published studies and of those only three systems were supported by more than five years of published data (Branemark, Straumann, Astra Tech).
He surmised that 90% of the systems available do not have clinical documentation of 5 years or more.
He quoted short and medium term implant survival rates of between 98-94%, pointing out that long term results still await the accumulation of accurate data.
These results are not only highly successful in themselves but in comparison to other implants in the body such as knee, hip, cardio vascular stents and heart valves, represents an extremely high rate of success.
However the data also highlights that with time complications arise both in the tissues surrounding the implant as well as in the implant restorations themselves.
The signs of disease in the peri-implant tissues are mostly infectious in nature and both local and patient risk factors intervene in the occurrence of these complications.
In addition to implant design, surgical technique, loading and occlusion, the main risk factors identified in implant survival rates included: systemic factors such as immunity, healing rate and adverse medical history, genetic factors, previous history of periodontal disease, smoking, nutrition, oral hygiene, patient compliance and implant maintenance techniques.
Professor Sanz also went on to discuss the composition of biofilms that accumulate around the implant itself, with some studies identifying different bacterial strains to periodontal infections.
On the whole however, he concluded that the main bacterial pathogens remain the same for peri-implant diseases as for the periodontal diseases.
The risks for the implant tissues lie in the fact that there is less resistance to bacterial colonisation, due to the lack of protection afforded by the periodontal ligament and crevicular fluid.
The peri-implant environment therefore is more conducive to destruction of the tissues with less resistance to microbial challenge.
The bony lesions associated with peri-implantitis are different to those seen in periodontitis in that the crestal height of the bone remains with circumferential bone loss around the length of the implant itself. In addition inflammation and oedema are not always present and can disguise an underlying lesion, emphasising the importance of correct probing techniques.
The presence of plaque biofilm and bleeding on probing increases the risk of peri-implant diseases by 30% and poor access for plaque control around the supra structure also decreases the odds of survival.
Professor Sanz concluded his presentation by summarising the basis of prevention, namely control of risk factors both local and systemic, effective maintenance, regular surveillance of the surrounding tissues and underlying bone with early non-surgical therapy when required.
Management of peri-implant infections
Professor Stefan Renvert has published more than 100 papers in international journals and at present his research focuses on the diagnosis and treatment of peri-implantitis, risk assessments and the associations between periodontal disease and cardiovascular disease.
Professor Renvert quickly pointed out the importance of early diagnosis and treatment of infection around implants. Infection control and the avoidance of re-infection is a necessary component of therapy if it is going to be successful.
This presentation focused on the different approaches to mechanical non-surgical treatment of peri-implant infections and clinical indications for the use of surgical intervention.
Professor Renvert looked at early complications in implant placement such as surgical trauma, post operative infection and dehiscence along with functional factors such as overload and excess cement remaining after placeOment of the supra structure.
He again highlighted the differences between the pathology of periodontitis and peri-implantitis and defined peri-mucositis as having clinical signs of inflammation, bleeding on probing and/or exudate, however the supporting bone remains intact. Conversely peri-implantitis involves bone loss, which is not always obvious from probing depths alone.
Probing techniques are extremely important as there is no clinical attachment between the implant and soft tissues. This means that the probe can descend all the way down to the crestal bone. He stressed the importance of employing both probing techniques and radiographic assessment in the surveillance of peri-implant infections.
For example if there is bone loss to the buccal or palatal walls this is not seen using radiographic techniques alone, it can only be fully determined in conjunction with peri-implant probing techniques.
A non surgical approach can be very successful with the correct techniques and adjunctive materials. The key is infection control, removal of biofilm and/or calculus from the implant surface and disinfection of the surrounding tissues.
When using hand instruments it is important to bear in mind the lack of fibrous attachment surrounding the implant structure itself, as the fibre arrangement in the tissues do not engage with the implant surface but are simply in close contact. It is important therefore to adopt a mechanical technique that strikes the correct balance between the removal of microbial accretions with minimal disturbance of the tissues.
Professor Renvert cited his findings in a clinical study he conducted using a glycine air polishing technique as being effective in the treatment and disinfection of the peri-implant site as the use of an Er:YAG laser.
This technique affords effective disinfection with minimal disturbance to the surrounding tissues. Using adjuncts such as chlorhexidine and/or local antibiotic therapy is also valuable when treating peri-implant diseases.
In more advanced cases a surgical approach is necessary, exposing the implant surface, removing granulation tissue and mechanically cleaning the implant surface. Where 3 or 4 wall defects are present he suggested bone regenerative therapy.
It is clear that in the treatment and prevention of the peri-implant diseases specific management techniques and protocols are important. Once surgical placement is successful, the hygienist is the key to the long-term survival of the implant and preserving osseointegration.
Understanding and identifying the signs and symptoms of peri-implant infection combined with early intervention and treatment of disease can maximise the long-term success of implant placement and function.
Juliette is presenting a full day hands on Master Class for Dental Hygienists on Saturday February 23rd 2012 at the Optident International Development Centre The course hosted by Optident and supported by American Eagle Instruments, EMS, Philips Oral Healthcare will focus on the essentials of implant care and maintenance of the surrounding soft tissues.
This hands on course will include the latest film release from Europerio 7, plus guest lectures, radiographic diagnosis, probing demonstrations and hands on sessions using some of the latest materials and instrument techniques in implant maintenance.
Participants will have the opportunity to use and evaluate new materials in implant maintenance and soft tissue management, pressure gauged implant probes plus new titanium hand instrument tip designs including the latest piezo-ceramic instrumentation and air polishing techniques for implant maintenance.
Places are limited to ensure individual attention. For more information visit www.perio-nutrition.com/Courses.html
Juliette Reeves is a dental hygienist and trained nutritionist with over thirty years experience. She writes regularly for the international dental press and is an editorial advisor to a number of dental journals. Juliette is a media spokesperson for Wrigley, a Key opinion leader for Philips Oral Healthcare, senior UK tutor to the Swiss Dental Academy and clinical director of Perio-Nutrition. Juliette regularly presents post graduate seminars in the UK and internationally. Juliette was recently elected ADI DCP Committee Member.