2017 Symposium Q&A
With a comprehensive range of presentations, many clinical and business management topics were covered at the symposium — and educators were available to answer attendee questions submitted during the event. Read on for answers to questions about implant treatment options, veneer cementation techniques, restorative solutions, bone grafting procedures, and more.
Dr. Chad Duplantis
Dr. Timothy Kosinski
Why is more distance needed mesiodistally between adjacent implants than between an implant and an adjacent natural tooth?
- A living tooth has a periodontal ligament around the root structure and thus has blood supply. An implant has no PDL and has bone integrated to the surface. Thus, blood has to come from the living tissue of the surrounding anatomy. It is best to space implants at least 3 mm from each other, but an implant can be a little closer to a tooth. The 3 mm separation between implants and the 2 mm separation between an implant and a tooth are minimum numbers, of course.
Why do you need more interocclusal space for a cementable implant restoration than for a screw-retained crown?
- Interocclusal space of 7 mm is needed to successfully retain a cemented-on crown. A height less than this may result in inadequate retention of the cementable crown upon the abutment. When the interocclusal space is 5 mm or less, a screw-retained implant crown is suggested because less clearance is needed because there is no abutment.
What dictates the papilla level around single-tooth implant restorations?
- The interdental papilla is supported by interseptal bone. Without interseptal bone support the interdental papilla is not maintained.
How long after implant placement do you place the temp crown?
- There are several clinical studies clarifying this issue. If a minimum of 25 Ncm of initial torque is achieved in the placement of a dental implant, a healing abutment can be placed, which extends out of the soft tissue and eliminates the need for an additional surgical procedure to expose the cover screw once healing and osseointegration are complete. If less than 25 Ncm is achieved, I suggest hand-tightening a cover screw into the implant, which allows the tissue to cover over the implant during the period of osseointegration. When 35 Ncm or more of primary stability is achieved, then the implant can be loaded immediately after placement. Although I personally do not immediately load my implants regardless of the torque achieved, if primary stability of 25 Ncm is present, I will place a healing abutment, congratulate my patient on his or her bone quality and tell them that there will be no need to anesthetize the tissue for final impressions after integration.
In the case you presented, if there had been periodontal issues or if the patient was a heavy smoker, would your choice of treatment had changed?
- Smoking always creates a problem. The heat generated from a cigarette or cigar can damage the implant, and the smoke, tar and nicotine can penetrate through the soft tissue, creating potential problems with integration of bone to the surface of the implant. When placing an implant for an active smoker, I recommend always burying the implant to try to get primary closure. Smokers also have significant changes in the blood supply to the soft tissue. Bleeding is important in primary implant healing. Although we advise our patient not to smoke during the healing stage, the effects of smoking in the past can last many years. If we do not have proper interseptal bone due to any periodontal condition, it is best to know it preoperatively and treatment plan accordingly. It may change the design of the final prosthesis and can have a negative impact on emergence profile and smile design. Crowns may need to be done on the adjacent natural teeth for esthetics, and the interdental papilla may be minimized.
Dr. Charles Schlesinger
When completing a bone grafting procedure, how do you decide if you need to use a membrane, or just a collagen plug?
- I will use a membrane if there is a missing wall or if I am placing an implant at the same time in a molar region.
Why do you recommend allograft and not xenograft?
- Xenograft can take 6 months or more to resorb and in some studies has shown an increased inflammatory response. In contrast, allograft will usually regenerate bone within 3–4 months.
For rehydrating the alloplast putty, do you prefer to use blood or saline?
- Both will work, but blood will add the advantage of platelets and other live cells that will kick-start the osseointegration process.
What do you carry the graft with? It’s hard to handle for me.
- There are bone carriers available through many companies. You can also use small, 1 cc tuberculin (TB) syringes without the needle. Make sure to rehydrate the material, too.
How are you preventing epithelial downgrowth with a collagen plug? Wouldn’t a PTFE (polytetrafluoroethylene) membrane be better?
- Soft tissue will only grow across something. If you fill the socket with bone and then place a collagen plug, the soft tissue will migrate laterally across the site. The key is having the graft material incorporated into the forming clot. PTFE membranes can be problematic with regard to bacterial infiltration, non-closure of the site and having to remove the membrane. In my experience, the plug has been a predictable procedure with good results.
Can you hydrate bone grafting material with peridex?
- I would not recommend it. Peridex contains alcohol and other ingredients. It is OK to rinse the site with peridex, but use saline, sterile water, anesthetic or blood to rehydrate your graft.
Dr. Jack Hahn
I just switched to a tapered implant. Sometimes after I use the final shaping drill, the implants don’t go all the way into place, especially in type 2 and type 1 bone. Why is that, and what should I do?
- With the Hahn™ Tapered Implant System, the tapered shaping drills are 3/10 mm narrower than the implants. In other words, they are the diameter of the implants between the threads. In type 3 and 4 bone, the aggressiveness of the Hahn implant threads allows the implant to be self-tapping and should take it to full placement.
- Type 1 and 2 bone are more dense. Therefore, I make several entries into the osteotomy with the final shaping drill until the drill is passive in the osteotomy. You should be able to push the drill to place without the hand piece running. After doing that, then use the screw tap and the implant should go into place perfectly and will have a good chance of achieving initial stability of 35–45 Ncm.
In your hands-on experience, what is the most predictable bone graft material?
- I have used most every kind of bone graft material that is on the market. I started using bone substitutes as early as 1977. It was tricalcium phosphate and turned out to be very unpredictable. About 10 years ago, I started using mineralized cortico/cancellous allograft particulate and it has never disappointed me. I still try other products with the hope that they would be even better, and I find out that they aren’t. Therefore I end up staying with the mineralized cortico/cancellous allograft.
Are the restorative steps more difficult for the BruxZir® Full-Arch Implant Prosthesis versus screw-retained acrylic hybrid dentures?
- There are no differences in restoring with full-arch BruxZir restorations compared to acrylic hybrids, except that you get a PMMA provisional prosthesis to confirm the design before the final restoration is fabricated from monolithic zirconia. I switched over totally to the BruxZir Full-Arch Implant Prosthesis over three years ago and haven’t looked back. Acrylic hybrids are a nightmare, with teeth breaking off, flanges breaking, food clinging to them and staining. Never had any of those problems with BruxZir, and the restorative protocol is very straightforward.
Does the Hahn implant have scannable components?
- The Hahn implant does have scannable components available via Glidewell Direct.
What are the differences between the Hahn Tapered Implant System and the Inclusive® Tapered Implant System?
- The Hahn Implants have more pronounced, aggressive threads and are more tapered, thus offering increased primary stability. Also, the Hahn system has a 7-mm-diameter implant, a 1 mm machined collar for soft-tissue maintenance, and increased platform shifting.
Dr. Anamaria Muresan
How do you break contacts after cementing multiple veneers at the same time?
- I like to use the serrated strips from ContacEZ® (ContacEZ; Vancouver, Wash.). At about 0.3 mm thick, they are very thin and delicate. For more tenacious veneer surfaces, I like to use the Jiffy® Proximal Saw (Ultradent Products, Inc.; South Jordan), which comes in a 0.4 mm size. I also use a microbrush to wipe off the excess before curing.
Dr. Raymond Choi
Should a dentist who is already placing conventional implants bother learning how to do mini implants?
- Most definitely! There are many clinical situations that may be more suitable for mini implants. For these patients, offering additional treatment options will greatly increase treatment acceptance. This way, the dentist is able treat patients who cannot benefit from conventional-diameter implant treatment.
How productive and profitable are mini implant procedures?
- Because many mini implant placement cases can be done in a flapless manner, surgical time is greatly reduced. Additionally, the prosthetic workflow is simplified because you are dealing with a one-piece implant. For example, lower denture stabilization, whether or not you’re making a new denture, requires minimal time compared to more invasive conventional implant placement and prosthetic protocols. Mini implant treatment remains as one of the most productive procedures in my practice — not to mention how happy patients are afterwards.
I currently do not place implants and only restore them. Can I easily learn how to place mini implants?
- With proper training, any dentist can place and restore mini implants very effectively. I offer a two-day comprehensive mini implant course with a surgical workshop featuring hands-on exercises with models. After completing this course, you should be able to place and restore mini implants with confidence.
Why not just place minis instead of conventionals?
- Just as there are cases that are more suitable for mini implants, there are many cases that are better suited for conventional-diameter implants. In fact, mini implants are adjuncts to conventional-diameter implants. Any prudent implant dentist should have both mini and conventional-diameter implants in the implant toolbox.
I have been told that mini implants break and have to be surgically removed. However, with the mini implants I have placed over the course of 10 years, I have never experienced this. What has been your observation over your 30 years of mini implant placement? How many fractures and failures (loss of the implant as a result of infection) have you observed?
- I have even seen a few conventional-diameter implants fracture in the past. Yes, mini implants can also fracture. Controlling any unfavorable occlusal forces is very important for all implants, especially minis. The restorative aspect of mini implants is crucial in protecting them from any unfavorable forces. When restored properly, fracture is not a major concern for mini implants. In my practice, I have seen very few fractures of mini implants. One situation where mini implants can fail is due to premature loading, especially when the implant does not have adequate primary stability.
What can you do if the mini implant cannot be immediately loaded for an overdenture?
- If desired primary stability is not achieved at the time of surgical placement, resilient soft liner can be used inside the denture, allowing for biological osseointegration of the mini implants. After three to six months of healing, the denture can be loaded.
What’s the best way to remove an integrated mini implant?
- In the mandible, you can cut off the implant at the osseous level. In the maxilla, you can try to back it out with a ratchet or torque wrench. Note that if the bone density of the site is good, the implant may fracture when you attempt to back it out.
Are the 3M™ ESPE™ mini implant parts and wrenches compatible with Inclusive Mini Implants?