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Dental Tribune Middle East & Africa Edition | January-February 2016 29 implant tribune < Page 28 > Page 30 I will come back later on this technique. Peel of the gums smoothly on the buccal side with the periosteuti. Take off high enough to help you “SEE WHAT YOU DO”. Surprisingly, you will see it is helping a lot! You are now facing an attrac- tive wall of bone asking for a window, you can now drill the way you want: ultrasonic, diamond bur… If you have no “Parkinson”, I feel and I rec- ommend the diamond bur, it is perfectly safe and much quick- er. Open the window from 2 to 3 mm above the bottom of the sinus: Why?: - To keep the bottom of the si- nus as a “bowl” for the graft - To make sure the edge of the crest will not explode under the pressure of the implants. Now softly lift off the mem- brane from the bottom of the sinus, the same way you would lift a carpet! Once more avoid “Parkinson” and take your time. This step is important, it is not a race! You will see many “movie stars” proud to say they are very fast. As a matter of fact, the quicker you work, the better is the healing, but the main point is to be accurate and smooth. The stop watch comes next… Now, big question: graft and im- plant in 1 or 2 times? You came to all the conferences of CAPP, you read a lot, you have watched many videos. The result may be as follows: “The more you try to learn, the less you know” For the same question in the same conditions, you may be told anything and its opposite… Maybe this is not really helping but the state of mind is often: big graft, big delay! Once more, I can tell you what I have done for more than 20 years. Don’t lose your common sense: a graft set in the bottom of a sinus is like a loose cargo in the bottom of a hold. As soon your patient walks or goes down the stairs, you can imagine how it is shaking. Be- yond the mechanical properties of the graft itself, what we will talk about in a minute, you can expect the fragile schneideirian membrane will not be a great help. Once more you should be prac- tical. Put a screw in the middle! If your graft is rolling, there will be no healing, not fiber growth, no new blood vessel, and you will fail. A stable graft is compulsory to get a predictable healing, with a stake in the middle: you make it a stiffer. One more benefit: you will save 3 months on the process and you have now a welcoming cav- ity for your counter plak and the way in. Look at the membrane it should move following the pace of the breathing like bellows: 2 options: - You stab the membrane, you rip it up. You need first to set a patch to protect it. Or, as a second ceiling, you set an absorbable membrane. For good,“resorbable” in 2-3 months, in time with the nat- ural process. - You did not stab it, you win. Go straight to the drilling of the socket with a tool as a shield between the drill and the membrane. Now a big question: What kind of graft? You have attended many lec- tures, read many reports, gone on internet: each time the material considered is the best and fits 100%. All the materials are the best! How can you make your mind? To enter the problem in a re- laxing way: “EVERY KIND OF GRAFT CAN MATCH!” and the market is wide.. First of course, you have the bones: - Antologue bone: seen as the best. No immunogenic reaction, but you need to harvest. If you take the graft on the chin or the ramus you may have pain, inflammation and paresthe- sia. If you use the hip or the skull, you get involved in a heavy process, too heavy. Allo graft, xeno graft are dry bone despecified with slow remodeling and a granular display which is not helping or a cubic display not easily matching. You have coral, hydroxy- apatite, calcium carbonates, bruschites, phospho calcic, ceramics, tricalcium phos- phates, biphase ceramics, polymers, bioglass, calcium sulfates, composites… The list is long… All materials can fit. Anyway, same as for your car. Four wheels and an engine means a car. Except some brands are better than the others! Again think simple: What do you need? The graft must be: - Easy to use - Hemostatic - Resorbable - Osteoconductive 1. Easy to use. Most of you have often got to fight with granulates stick- ing to everything but the cav- ity you want to fill. The bone substitute may be trodden and must not crumble. - To get a homogenous bone, it is better to make an homog- enous draft. - Granulates outside the cav- ity, between the cortical and soft tissues, unease the heal- ing and may be an open way for bacteria. With a kind of sponge mixing collagen and mineral phase, your graft will be reposition- able, malleable, stable, clean and will not migrate. 2. Hemostatic The blood is useful to start the healing process but, when it becomes a flush, it can move your graft and you can hardly see what you do. This means some collagen type III to start a quick clot. 3. Resorbable What you set is not a ready- made bone, it is a mock up for the natural bone to come. 4. Osteoconductive The “mock-up” has to be at- tractive for the osteoblasts and the bone substitute has to be easily integrated in the new structure. For good, instead of choosing between small and big gran- ules, to fit well, we should mix: - Under 80 um : too small granules create inflammation and resorption: avoid - Between 80 um and 200 um: small granules fit well to the defects and increase the reac- tive surface. - Beyond 500 um stands the pressure of the soft tissues. The wider it is, the more, you get hollows welcoming stemm cells. Today, the best I have found is MATRIBONE from BIOM UP. It is a kind of sponge you can shape, cut. It is malleable, repositionable and doesn’t crumble. It is made of a 10% frame of collagen type I and III surrounding 90% of mineral biphasic 60% Hydroxyapatite, 40% tri calcium phosphate. What happens in you graft? - First hours: collagen type III, which is roughly made of several type I, has a surface that activates the platelets and makes with fibrin, a quick and stable clot. - First days: granulation tis- sues, then remodeling tissues. - One week: macrophages, cytokines, growth factors start micro vascularization - First 2 months: new vas- cularization in new growing time created by osteoblasts. Osteoclasts are at work, you find stem cells in the lacunae. - 8 months: dense bone is available, osteoblasts become osteocytes. What happens in the sinus af- ter some months? Let us see more samples: Histological evaluation of hu- man bone tissue after bone reconstruction with MATRI BONE, a collagen–based bone graft substitute, in dental and maxilla facial surgery. Process: 1. Collection of a bone biopsy at the center of the treated site with a trephine bur. 2. Fixation in 70% ethanol, dehydration and inclusion in methyl methacrylate resin. Re- alization of 7 microns sections (NOVOTEC laboratory, Lyon, France) 3. Trichrome Goldner staining and microscopic analysis. Case 1: Biopsy after 4 months: 45 year old female, 16 extrac- tion, bone deficit in height and thickness. Dental Tribune Middle East & Africa Edition | January-February 201629