I case study_ flapless implant placement Flapless implant placement with an internal sinus lift using dynamic guided navigation Author_Naheed Mohamed, DMD _Today, implant surgery is fo- real-time three-dimensional drill guidance during cused on being minimally invasive implant surgery. One of the main advantages of this with an emphasis on prostheti- Navident system is that dynamic navigation allows cally guided implant placement.1 intra-operative changes to implant position in real Implants that are not placed in a time if any errors or anatomical complexities are prosthetically favorable position noted during the surgery.5 The flexibility of having a are at risk for future complications guided implant placement in a digitally planned ideal involving the prosthetic compo- location without the need for a static surgical stent nents or peri-implant tissues.2 and having the osteotomies live navigated on CBCT Successful implant placement is data using optical tracking is a game changer for im- not only judged by osseointegra- plant dentistry. This open system also has the flexibil- tion but also the esthetics. In a ity of using any implant system and any drill to guide climate where implant therapy is placement. The case presented below showcases the held to the highest of standards, flexibility of real-time navigation where Straumann using advanced tools to simplify implant drills are used for placement of an implant surgical dental implant placement with a simultaneous internal sinus lift using the Hios- is a requisite for success. sen CAS-KIT drills with the Navident system. Currently computer-guided Fig. 1_The Navident system surgery involves the use of a CBCT (cone-beam com- _Case report is shown here with the Micron puter tomography) scan and possibly an intra-oral Tracker and laptop loaded with scan to allow personalized digital surgical planning. The patient was a 57-year-old healthy female the Navident software. This plan is then transferred to the patient in the who was referred to our clinic to replace the missing form of surgical guides to aid in accurate implant maxillary second premolar at the 2.5(13) site with (Photos/Provided by Dr. Naheed placement. These guides, however, are static and do a dental implant. The Navident workflow consists Mohamed and ClaroNav Inc.) have some drawbacks. They are not always stable of four main sequential steps: stent fabrication, CT depending on whether they are supported by teeth, (computer-tomography) scan with the stent and mucosa or bone. Limited mouth opening does be- affixed CT marker in the patient’s mouth, digitally come an issue when surgical guides are used to place planning the implant surgery in the Navident soft- implants for posterior dentition.3 And, lastly, if there ware and, lastly, completing the live guided implant is any error in the digital planning, segmentation of surgery. One of the biggest advantages of the the anatomy or data transfer to the guide fabrication, Navident system is that these four sequential steps the error is passed down onto the guide’s implant can all be completed in one appointment, provided position.4 If errors are noted during surgery, then the the clinic has an available CBCT scanner. guide essentially becomes useless. The NaviStent functions as a retainer onto which The next evolution in guided dental implant sur- the CT marker is affixed to while the patient under- gery comes from neurosurgery and orthopedic spine goes her CBCT scan. The NaviStent is a custom single- surgery, where it has been used for quite some time. use retainer made of a thermoplastic material called ClaroNav Inc., has developed a live navigation system Naviplast then can be heated in hot water and molded using optical tracking cameras (Fig. 1) during implant to the patient’s dentition. The stent was trimmed, surgery to provide the surgeon with CBCT-based and the planned implant site was cut open to expose implants 10 I 1_2017 I case study_ flapless implant placement Fig. 2_A screenshot from the Navident software showing the digitally planned crown and implant (yellow) placement. Fig. 3_The drill is shown here being calibrated on the Fig. 2 Fig. 3 JawTag, which is fixated to the NaviStent in the patient’s mouth. Fig. 4_The clinical view of the handpiece being used to drill the osteotomy as it is being guided on the monitor. Note the DrillTag shown above attached to Fig. 4 Fig. 5 the surgical handpiece that allows it to be tracked. Fig. 5_A screenshot showing the Navident software navigating screen while the drill (in green) is being live guided against the CBCT cross sections. The CBCT cross-sectional views as well as the target bull’s eye on the left allow the Fig. 6 Fig. 7 surgeon to navigate the drill to the ideal digitally planned position. the ridge. The CT marker was then fixed to the stent drilling depth and use the live navigation to guide us Fig. 6_An immediate by way of a thumb screw. The NaviStent with the to the sinus, a digital implant was placed in the ideal postoperative clinical view attached CT marker was placed into the patient’s location with respect to the digital crown. This digital of the surgical implant mouth. The stent was checked for stability in the plan would guide us to the sinus floor for the sinus site, showing the flapless patient’s mouth. A CBCT scan was completed for the elevation and allow ideal implant placement. surgery of the single-stage entire maxillary arch, being sure to include the arm of implant-guided placement the CT marker, which contains the aluminum fiducial. _Live navigation implant surgery with a healing abutment. The CBCT scan was then imported into Navident and internal sinus elevation software. The Navident software automatically reg- Fig. 7_ Postoperative isters the fiducial and asks you to inspect the registra- The patient was seated for the implant surgery. peri-apical radiograph tion to ensure there is no malalignment. Our implant Local anesthetic was given. The single-use JawTag showing a Straumann Bone position is prosthetically determined, so our first step was fixated to the NaviStent with the provided Level Tapered 4.1x10 mm was to place a virtual crown at the 2.5 (13) site. The thumb screw. The tag adapter was mounted onto the implant placed with an vertical height of bone from the ridge to the sinus surgical handpiece and fastened in place, accord- internal sinus elevation. floor was measured using the software measuring ing to the company’s instructions. The single-use tool and found to be 7.4 mm (Fig. 2). DrillTag was attached to the tag adapter on the Our treatment plan involved placing a Straumann surgical handpiece. The NaviStent was placed into Bone Level Tapered SLActive Roxolid 4.1 mm x 10 the patient’s mouth with the JawTag visible for the mm implant as a single-stage flapless approach with Navident camera to detect. an internal sinus elevation. Taking advantage of the Once the CT markers are visible by the camera, freedom of the Navident system, we were able to plan they become visible on the side panel on the moni- our surgery to place a Straumann dental implant and tor. The next step was to calibrate the drill axis by complete our internal sinus lift using the HIOSSEN placing the handpiece head onto the calibration peg CAS-KIT (Crestal Approach Sinus Kit). To control our present on top of the JawTag. The handpiece was implants 12 I 1_2017 case study_ flapless implant placement I then rotated back and forth around the peg to Once the membrane was exposed through register and calibrate the drill axis. The system the osteotomy, it was elevated using hydraulic _about the author then prompts us to calibrate the drill. The initial pressure with the CAS-Kit Membrane Lifter precision point drill was then placed onto the and sterile saline. Cortical allograft chips were handpiece and calibrated by placing the drill then gently pushed into the void created from tip into the dimple present at the center of the the membrane elevation. The jaw stent was re- target on the JawTag (Fig. 3). Once the drill tip moved, and the implant was placed through the was calibrated, it then became visible on the osteotomy with direct vision. The Straumann monitor against the CT image when it is placed Bone Level Tapered 4.1 mm x 10 mm implant into the surgical field. was placed with 50 Ncm of primary stability. A Our next step was to verify the drill tip posi- healing abutment was then hand-torqued in tion. This was done easily by placing the tip of place (Fig. 6). the bur on a landmark in the jaw to verify ac- A postoperative peri-apical radiograph (Fig. curacy of its positioning. In our case, the tip of 7) was taken to assess the implant placement. the drill was verified by placing it on the cusp tip The implant can also be live navigated into of the neighboring tooth 2.4 (13). The drill was place; however, it needs to be calibrated by then brought to the surgical site (Fig. 4), and touching the tip of the implant over the JawTag the navigated drilling screen comes up, which dimple, and because of the risk of contamina- shows a target view and cross-sectional views tion, we chose to place it with direct vision. The of the CT images with the drill image visualized company recommends placing a sterile piece Dr. Naheed Mohamed received his bachelor of in its real-time position (Fig. 5). The target and of nylon over the dimple when calibrating the science degree from the cross-sectional views allow you to position the implant to keep the conditions sterile.