IDEM Singapore 2012: Papillas, platform switching, extractions and immediate placement

A truly outstanding line-up of top speakers will headline the Scientific Program of IDEM Singapore 2012, themed Advances and Controversies.

In addition to the plenary sessions in one hall, intensive full day programmes will run concurrently in another.

On Saturday, April 21, Prof. Dennis Tarnow will deliver a full day programme on Immediate versus Delayed Socket Placement and the Interdental Papilla Dilemma.

Dr Tarnow is currently Clinical Professor of Periodontology and Director of Implant Education at Columbia School of Dental Medicine. He has a certificate in Periodontics and Prosthodontics and is a Diplomate of the American Board of Periodontology. He is a recipient of the Master Clinician Award from the American Academy of Periodontology and Teacher of the Year Award from New York University. Dr Tarnow has a private practice in New York City and has been honoured with a wing named after him at New York University College of Dentistry. He has published over a hundred articles on perio-prosthodontics and implant dentistry and has co-authored three textbooks including one in 2008 titled Aesthetic Restorative Dentistry.

Good afternoon Professor Tarnow and thank you for your time. We're excited about your upcoming program in Singapore in April and have prepared some questions for you about your programme and the latest advances in implant dentistry.

Q:Firstly, do immediate implants placed into extraction sockets have a higher failure rate?

A:There has been clear research that immediate implants have the same high success rate as implants placed into healed sites. However, it is always about case selection and execution. The buccal plate must still be present after the extraction and there ideally should be at least three to five millimeters of bone apical to the socket to lock the implant in firmly.

Q:When you place implants immediately into extraction sockets, do you always place a bone graft into the "jump gap"?

A:I place a small particle mineralized bone graft into the buccal gap. Our research, which I am presenting at IDEM Singapore 2012, shows that the shape of the ridge six months post-extraction is least changed if a graft is placed along with a provisional out of occlusion. My preferred graft material, as mentioned previously, is small particle mineralized bone. We are presently looking into which graft material is better - bovine or allograft.

Q:Do you then place a barrier membrane after the graft?

A:I never place a membrane over the gap. The provisional is the only protection over the gap graft. I never open a flap so a membrane is not used.

Q:What are your key clinical/patient selection criteria when considering immediate implant placement?

A:The key clinical ingredient for immediate socket placement in the aesthetic zone is that the facial plate of bone must be present. The second important part is enough bone both apically and laterally to stabilize the implant into its proper position.

Q:What are the advantages of undertaking immediate implant placement and loading as a flapless procedure?

A:Immediate implant into fresh extraction sockets should always be done flaplessly. If the flap is opened, then the buccal plate of bone is subject to increased resorption. In fact, most research shows this to be about 4-5mms in a horizontal dimension. Without a flap, the amount of buccal lingual dimension change is only about 1 mm. This is because the facial periosteum covering the facial plate of bone is the only significant blood supply left after the ligament blood vessels are removed as a result of the extraction that was just done.

As for loading, single implants should never be placed into occlusion during the first two months of healing. The remaining teeth should be allowed to take on the forces of occlusion. We need to prevent any more than 150 microns of lateral motion occurring during this early healing phase.

Q:Do you still undertake immediate implant placement and loading in cases where there is loss of labial bone?

A:I never do immediate placement in the aesthetic zone when the labial plate is missing. My rule is very simple in the aesthetic zone: No Buccal Plate then No Implant Today.

Q:Can immediate implant placement be undertaken in infected tooth sites? What is the evidence?

A:Immediate placement can definitely be placed into infected sights. However, meticulous debridement must be performed. This sometimes means that a submarginal incision (to protect against recession of the facial gingiva) is performed if the apical tissues cannot be completely cleaned out through the socket opening. This is particularly true if there is a large granuloma or cyst at the apex before extraction.

Q:When immediately placing implants into extraction sockets, what specific clinical steps do you undertake to preserve the inter-dental papilla?

A:The papilla is never touched during the extraction. This means that no flaps are raised at all. This is the key to minimizing recession of the facial tissues as well as the papilla.

Q:Can we predictably regenerate papilla between two dental implants?

A:We are still not able to predictably regenerate a papilla between two implants. The reason is that we must be able to get supra-crestal biologic width on the implants and/or abutments. This is what most of our research along with others in the world are focusing on at this time. We are working towards using ovate pontics into ridges that have been built up between implants.

Q:Do platform switching implants provide more predictability in maintaining inter-dental papilla between implants?

A:Platform switching allows us to get implants closer together without losing the inter-implant bone. This is certainly helpful but not the entire story. Just placing two platform switched implants next to each other does not mean that the papilla will be the normal height that it is between two healthy teeth. As mentioned before, we also need to have the epithelial attachment and the connective tissue adherence in a supra-crestal position. This needs attention to detail both surgically and restoratively.

Q:Does planning staged extractions for multiple implant placement in the anterior aesthetic zone allow for more control of the gingival tissues? Does a sequential extraction and implant placement protocol significantly enhance the long-term aesthetic result?

A:Doing sequential placement has been reported to help two maxillary centrals in some case reports. However, there is no standardized controlled study to prove this yet. It certainly may be helpful but once both adjacent teeth are removed then the papilla normally shrinks down. This is particularly true between a central and lateral incisor where if recession takes place, then the difference with the contra lateral side becomes very obvious. When it is between two centrals, then we "get away" with this because the recession is in the mid line and therefore there is no asymmetry to the smile, even if the papilla is a little shorter then normal.

Q:What are the key features of an immediate provisional implant restoration that help maintain gingival aesthetics facially and interproximally?

A:The key ingredient for immediate provisionalization is proper contour subgingivally. The provisional should be similar in shape to the tooth that was extracted. There should be no ridge laps in the provisional and the contact point should be at the same height as the tooth that was there before it was extracted.

Q:Finally, has orthodontic extrusion of a tooth prior to extraction and immediate implant placement been superseded by GBR and soft tissue grafting?

A:Orthodontic extrusion is a wonderful tool that will never be completely replaced by any type of grafting. If the tissue and bone is missing on the tooth that you need to remove, then extrusion can bring down the bone and the soft tissue around the tooth. This is particularly key in cases where the interdental papilla is missing or short before extraction. There is no predictable way to surgically regrow a papilla. The only short proof way is to erupt the tooth and let the papilla come with it. After movement, one should also hold that tooth in its new position if you want to develop more coronal bone, since it will take about that time for the tension on the ligament fibers created by the eruption to allow for bone to be deposited to shorten the ligament back into its normal length. In today's high level practices around the world, it should be clear that one must have access to an excellent orthodontist that understands how to deal with adults and knows what the restorative dentist and implant surgeon is looking for. This is in contrast to orthodontists that only handle children and don't understand what the goals of their treatment is for the adult "sight development" patient.

IDEM Singapore 2012 conference and trade exhibition is being staged from April 20-22. For more info, visit www.idem-singapore.com.