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12 mCME Dental Tribune Middle East & Africa Edition | 3/2017 Minimally invasive implant placement without the use of biomaterials using the bone expansion technique CAPP designates this activity for 1 CE Credits mCME articles in Dental Tribune have been approved by: HAAD as having educational content for 1 CME Credit Hours DHA awarded this program for 1 CPD Credit Points By Dr Gilles Chaumanet, France The success rate in implantology is close to 96 percent. Thanks to well- established implant placement protocols, with a few differences ac- cording to the implant system used, the predictability of the result under optimum tissue conditions is quite signifi cant. It is very different when these conditions do not meet the recognized standards in terms of vol- ume and quality for reproducibility in implantology. For example, thin ridges, which are frequent occur- rences, will require a long and costly process for patients because they en- tail bone augmentation or possibly support tissue grafts. Is there a minimally invasive alter- native for these patients that allows them to be treated without these problems? One line of thinking is to stop the systematic practice of im- plantology as subtractive at the tis- sue level, but rather to transfer these volumes and thereby ensure a mini- mally invasive procedure. This im- plies reviewing all the biomechanical principles of implantology, not only in terms of the implant structure and design but also in relation to peri-implant tissue. The general surgical principle of modern implantology since Bråne- mark has been bone preparation, called osteotomy, as close as possible to the dimensions of the implant that will be placed. This principle is still widely prevalent. However, soft-tissue management has evolved, and the trend the past few years has been to manage soft tissue from the fi rst surgical step. With the arrival of self-tapping coni- cal implants, a new technique was developed that enables lateral as well as vertical bone compressing, con- densing or expanding. In addition, in 1994, Summers, practicing his cr- estal sinus lift technique with careful choice of conical taps, was the fi rst to demonstrate the capacity of cancel- lous bone to be modeled (Fig.1). Through two clinical cases, we will see it is possible to be minimally in- vasive, precise and also avoid the use of biomaterials simply by exploit- ing the biomechanical properties of bone tissue and its capacity to re- generate. Respecting guided regen- eration principles, which means the implementation of physical barriers to isolate the epithelial and connec- tive tissue cells from the operating site, enables regeneration of the different tissues. These principles are (Fig. 2): • Primary closure of the surgical site to enable undisturbed and uninter- rupted healing. • Completion of the best possible angiogenesis to provide the required vascularisation and undifferentiated mesenchymal cells. • Creation and maintenance of a space to facilitate bone formation inside this space. • Stabilization of the surgical site to induce blood clot formation and fa- cilitate healing. Thanks to the careful choice of the healing screw or the implant abut- ment/temporary crown pair, these two entities with different regenera- tion potentials can be hermetically sealed, thereby avoiding cell compe- tition, which we know contributes to the growth of epithelial cells which develop more rapidly. Case 1 The patient presented with a fracture of #16 (Fig. 3) and periapical cysts. With the patient's consent, the deci- sion was made to perform an extrac- tion, debridement, socket decontam- ination and immediate placement of a non-submerged implant (implant and healing screw) using Summers' method (crestal sinus lift). The pa- tient was on standard premedication with amoxicillin and corticosteroids. The #16 was carefully extracted by radicular separation to avoid bone fracture especially in the vestibule where the cortical bone is very thin. The lamina dura, which enables the attachment of collagen and Sharp- ey's fi bres, presents a high potential for contamination. Consequently, a light manual curettage of the socket was carried out, followed by a super- fi cial debridement (vaporisation) of the entire “lamina dura” with an Erbium laser (2,870 nm) followed by decontamination with a diode laser (940 nm). This was a fl apless surgery. The ex- pansion osteotomy was performed through the inter-radicular septum. It was initiated with a very thin man- ual bone tap (pointed) and then an automatic mechanical osteotome (Figs. 4-5) (Osteo Safe®-Anthogyr) was used. The use of convex inserts in the beginning enables lateral ex- pansion of the native or healed bone and then concave inserts during the breaking of the last sub-sinus mil- limeter, enables lateral bone recov- ery of this bone socket while project- ing it apically. During sinus progression PRF mem- branes (or native collagen mem- branes) are placed in the osteotomy opening to fi ll the intra-sinus space that is thereby gained (they also pro- vide protection of the sinus mem- brane). The Erbium laser is again passed through the osteotomy socket to vaporize the bone debris and sludge along the walls of this osteotomy. The implant is placed according to the manufacturer's recommenda- tions but with an even slightly high- er torque if the titanium grade so allows. A healing screw that fi ts the diameter and height of the residual gap to be closed is carefully chosen (Fig. 6). If the healing screw does not enable primary closure of soft tissue, PRF membranes are used to fi ll the gap. If this gap is too big, a mucoperiosteal detachment of 6-10 mm and then a horizontal incision of the periostium of 6-8 mm are made. This technique serves to pull the gum around the healing screw by maintaining it with two sutures. The control X-rays clear- ly showed good osseointegration of the implant, signifi cant fi lling and regeneration in only three months, and then perfect fi lling and regenera- tion four months after surgery. The bone remodeling around and above the implant neck also seemed ÿPage 13 Fig. 1. Original explanatory sketch of Summers' technique. Fig. 2. Bone expansion through the septum with the use of osteotomes (a, b). Choice of healing screw that enables primary closure of soft tissue (c,d). Fig. 3. Preoperative clinical view of #16 fractured and infected Fig. 4. Use of OsteoSafe Fig. 5. Complete OsteoSafe Kit Fig. 6. Bone expansion (a), positioning of the implant (b) and choice of the healing screw (c) Fig. 7. Panoramic views: a) Pre-op. b) Per-op., c) at three months, d) follow-up at one year. Fig. 8. Control at six months Fig. 9. Preoperative view of Fistula on 24 Fig. 10. Panoramic view with Gutta-Percha cone inserted in the fi stula that reaches the apex Fig. 11. Laser decontamination