3D CBCT Case Study CBCT Scanning in Sinus Bump Cases Robert E. Walinchus, DMD DICOI

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1 3D CBCT Report August 2011 Issue 3D CBCT Case Study CBCT Scanning in Sinus Bump Cases Robert E. Walinchus, DMD DICOI With the advances in technology it has been the goal of dentists today to perform advanced procedures on patients with the least invasive treatments possible. Take for example the placement of an implant in the posterior maxilla. This is a simple procedure provided there is enough bone. The problem arises, however, when the patient has been partly edentulous in the area long enough for the pnumanization of the sinus to occur and bone height is not adequate for implant placement. As depicted in Fig. 1, we have just such a case with four views provided by the PreXion3D CBCT scanner. As an overview, the initial four views provided by the software are adequate to evaluate the next step for the practitioner and to provide visual information for discussions with the patient as to the expected course of treatment. After evaluating the PreXion images, it was determined that in this case a sinus bump would be performed instead of a full lateral window surgical technique in order to provide a satisfactory result with minimal complications as can Fig. 1 occur with lateral window surgery. This technique is available to the implantologist due to the accurate fields of view that the scan provides. In Fig. 2, we see that there is nearly 7 mm s of available bone and the patient can have a large diameter 9.0 mm Biohorizons implant and only need the bone to recover 2.5mm s of growth over the implant placed under the sinus membrane. BTI protocol was used to create PRGF for mixture with the bone graft particles for enhanced healing over the implant and under the sinus membrane. This was prepared prior to implant preparation and was the result of the careful phlebotomy of the patient and spinning the blood to create a growth factored medium for bony proliferation (Fig 3). After the flap was reflected the area is selected as a starting point from the enhanced CBCT images. This area corresponds with the exact measurements of bony areas as shown on the scan in Fig. 4. Landmarks can be calculated from structures noted from these enhanced views. The initial osteotomy was performed with a starter 2.0 drill from the Biohorizons tapered kit. These drills are especially noteworthy as they are marked beginning Page 1 of 3D CBCT Report

2 at 6.5mm s which should enable easy viewing during osteotomy preparation. The osteotomy is drilled to the measured mark 1-1.5mm s short of the floor of the sinus. This will give the implantologist the ability to control the entry into the sinus by gentle pressure (Fig. 5). Hand osteotomes were then used to press bone graft ahead of the pending implant and begin to gently up fracture the floor of the sinus. These Salvin osteotomes have a depth gauge that can be set to the desired length of implant to be placed and a concave tip where bone graft can be gathered much like an amalgam plugger and delivered to the site easily (Fig. 6). Fig. 2 Successive sizes are used to widen and continually press up the floor of the sinus. The depth stop prevents the practitioner from pushing too far. The particulate bone graft acts as a buffer between the osteotome and the bony floor allowing gentle pressure without ripping the bone into the membrane (Fig. 7). Previously the plate was up fractured by tapping the bone. This usually caused significant ecchymosis or at least a very unpleasant sensation for the patient. The advent of CBCT technology such as the PreXion with high quality images allows the clinician to precisely measure to the sinus floor making the floor very thin and easily fractured with hand pressure only. Fig. 3 Once the floor of the sinus has been penetrated and the osteotome has been pressed to depth the area can be checked for intact membrane with the implant probe provided with the implant kit. If still intact the case can proceed. Now the PRGF enhanced mineross bone graft can be placed with gentile pressure upward further moving up the membrane allowing a large space for the implant (Fig. 8). Fig. 4 The margins of the osteotomy should be freshened with the final osteotomy drill. The practitioner should however, be careful not to penetrate into the sinus too far as to perforate the membrane. Once completed the implant can be placed, and sutured to closure. X-rays taken post procedure (Fig. 9) show a large area of bone graft still gathered by the overlying membrane. This area will compact down in coming months and provide adequate bone on top of the implant for longevity. Also Fig. 5 Page 2 of 3D CBCT Report

3 noted here is the bi-cortical stabilization of the implant upon immediate placement. This stabilization prevents any type of micro-movement of the implant thereby further assuring success. Fig. 6 In conclusion it is evident from this depiction of a case that the techniques for implant placement are made easier with the advent of enhanced technologies such as CBCT scanning. These images as shown here are real and not digitally enhanced in any way and they represent the actual case as performed. With the use of these technologies a practitioner can perform more advanced types of cases like sinus bumps quickly easily and without the tapping that used accompany previous surgeries of this type. By being able to exactly find the floor of the sinus by mm s the dentist can gently press up the floor giving patients a better experience for overall implant placement. This in turn can be a practice builder that will bring more implants cases to any practice. Fig. 7 Fig. 8 Fig. 9 About Dr. Walinchus Dr. Walinchus received his Doctor of Dental Medicine Degree Temple University School of Dentistry in 1984 with Awards in Pediatrics and Radiology; admitted to the Oral Surgery Honor Society. He received his Bachelor of Science Degree in Biology from Mount St. Mary s College. Since 1984 he has been in a family and cosmetic dentistry private practice in Springfield, Pennsylvania. Dr. Walinchus has served the dental community many leadership positions and has his Fellowship from the ICOI (International Congress of Oral Implantologists), is a member of the American Dental Association, Academy of General Dentistry, American Association of Hospital Dentists, American Association of Dentistry for the Handicapped, American Association of Geriatric Dentists and the American Academy of Cosmetic Dentistry. He lectures nationally on CT guided implant surgery. Page 3 of 3D CBCT Report

4 PreXion360 Marketing Guide We are happy to announce that you have received or will be receiving our new PreXion360 Marketing Guide. This guide will give you the tools to successfully integrate 3D Cone Beam imaging technology into your current marketing strategy, and help you develop programs that will attract new patients, improve patient retention rates and help grow your practice. When lecturing to dentists about how to market their practices, I always stress the importance of differentiating their practices from others in the community. Interestingly, surveys show that most dentists believe they are differentiating their practices, but unfortunately they are doing it in the exactly the same way! includes sections on why your practice brand is important, defining your brand, fostering and maintaining a competitive edge, ensuring that everyone in the practice is in sales and marketing and how to empower your patients to make educated decisions that will have a The PreXion360 Marketing Guide positive impact on their oral health. The PreXion360 Guide includes a marketing materials CD-ROM filled with useful tools and materials you can use to market your practice. The following is a list of marketing guides With your purchase of a PreXion3D imaging system you are on the forefront of advanced technology and have something that 95% of your competitors do not have in their practices, so it is important that you let your community know about this important and clinically significant investment you have made. While we will continue to improve and build upon the PreXion360 Marketing Guide, it is currently very robust and provides you with tools and materials to successfully market your practice. We look forward to receiving input from you to help us further improve this guide. The PreXion360 Guide starts off with a brief but powerful primer about how to market your practice in general. It PreXion360 Guide Page 4 of 3D CBCT Report

5 Imaging Reimagined Imaging Reimagined Imaging Reimagined PreXion Postcard Imaging Reimagined PreXion3D Cone Beam CT takes x-ray imaging to the next dimension by providing 3D images that allow your dentist to safely and accurately diagnose and customize your treatment like never before. PreXion3D combines the highest quality 3D images and the most powerful software in the industry, dramatically reducing radiation exposure, and enhancing your dentist s standard of care. <Practice Name> <Doctor s Name (s)> <Address 1> <Address 2> <City> <State/Province> <Zip Code> <Phone> < Address> <URL> Call us today for an appointment. PreXion Poster PreXion Ad PreXion Patient Brochure designed to help you create a successful marketing strategy: PreXion S.W.O.T. Analysis A S.W.O.T. Analysis is a tool used to identify your practice s Strengths, Weaknesses, Opportunities, and Threats. This information will help you position your practice in the marketplace, identify areas that you should be emphasizing in your marketing, areas where you need to improve, and areas you might not have seen that will take your practice to another level. PreXion Practice Analysis A Practice Analysis draws on your experiences as a consumer by identifying the strengths and weaknesses of companies that you have dealt with in the past and integrating those findings into your practice. PreXion Patient Survey A Practice Survey will help you gather important information from your patients that will allow you to better serve them. PreXion Patient Profile Building a Patient Profile will help you identify your target audience by taking the information gathered from your patient survey, and organize it in a way that will allow you to spot trends and similar characteristics in your patients. PreXion Patient Survey Results We have gathered the results from three PreXion customer s patient surveys. Hopefully their findings and the programs they enacted will aid you in your own survey. PreXion Marketing Materials The following are a list of speciallydesigned PreXion marketing materials you can customize and use in your practice: PreXion Patient Brochures PreXion Ads PreXion Postcards PreXion Posters PreXion How-Tos Our How-To guides will help you navigate through some of the PreXion3D Cone Beam Scanner s most advanced features. PreXion Image Library On the CD-ROM, you will find a large library of clinical applications and product images that you can use on your website, and other marketing materials. Page 5 of 3D CBCT Report

6 The Imaging Chain Optical vs. Digital Zoom In previous issues in the Weakest Link articles, we discussed the critical importance of a small focal spot and also coordinated voxel size in determining image quality and diagnostic capability. The entire PreXion3D system is dedicated to and focused on producing the highest quality and most diagnostic images in the industry and not having any weak links in our Imaging Chain. In this issue we ll cover the role of Optical Zoom vs. Digital Zoom in producing clear, precise and accurate images. 1. Focal spot size 2. Voxel size 3. Optical vs. digital zoom 4. Degree of rotation 5. Number of projections/images taken 6. Software capabilities Optical vs. Digital Zoom The last time you purchased a camera you undoubtedly saw advertisements claiming things like up to 36X zoom. The problem with these claims is this camera may have only had an optical (sometimes called true ) zoom of 5X. With my compact waterproof fly fishing camera, I rarely use the telephoto function for scenic views because the image quality is not so good since most of the zoom function is done digitally. Quality cameras utilize a high level of optical zoom, i.e. the camera uses the lens to draw the image closer similar to the way binoculars work. Optical zoom retains a high level of image quality so the full resolution of the camera can be used on the zoomed image. Using a digital zoom function, the optics in the lens do not move or change and the image of the subject being photographed doesn t actually come any closer. Digital zoom is essentially what you do on your PC taking a portion of the image and expanding it, so the section of image you are looking at becomes bigger, not closer, which results in a degraded image quality. Some CBCT systems use digital type zoom functions for changing various Fields of View (FOV). To avoid any weak links in our system, PreXion uses a mechanical/ optical zoom to obtain the 5x5 FOV rather than cropping the detector. This is similar to digital images where optical zoom changes focal length and magnification as it is zoomed. Image quality stays high. Digital zoom crops the image to a smaller size, then enlarges the cropped portion with a significant loss of quality. Page 6 of 3D CBCT Report

7 PreXtips The PreXion system and PreXion3D viewer software are both very powerful tools and PreXTips will help you better utilize the many tools included with your system. In order to create higher quality saved images from the PreXion3D Viewer and make them as useful as possible for your marketing needs, print materials and other purposes, you need the largest, highest quality image/file possible or you will be limited to poorer resolution. This will also limit the size that the image can be blown up to without degrading. The following instructions will show you how to save images in a format that will have a higher resolution: 1) Go to the viewer, maximize the window (Fig. 1) and then maximize the 3D or MPR view to full screen size. For instance, double click on the 3D window to get a full screen 3D image (Fig. 2). Fig. 1 2) Click on Preferences in the top right of the viewer window (Fig. 3). 3) Select the tab Capture (Fig. 3). 4) Check View Size and Using Bmp (to avoid jpg compression artifacts) (Fig. 3). Fig. 2 Fig. 3 5) Right click on the image, make sure you change the lower drop down menu to Save as type Bitmap Files (*.bmp) and then save the image to your appropriate folder. These images should be approximately 2-3MB s. Images typically saved from PreXion3D Viewer, without taking the above steps, will be automatically saved as.jpg files, and will be a relatively small file that is only about 40-60KB. If you need additional assistance with this procedure, call us toll free at PreXion Page 7 of 3D CBCT Report

8 Clinical Case Tim Miller, DDS, BSc San Rafael, CA Initially I purchased the PreXion3D system to plan implant cases. Having a CBCT in your own office demonstrates to patients a commitment to not only implant dentistry, but to state of the art diagnostic technology. I planned to apply this technology to implant dentistry and 3rd molar extractions, but in the process found many other uses. I wasn t surprised that endodontics was much more predictable, as I can see the number and the shapes of canals before I touch the tooth. What I didn t realize is the help it can be for periodontally diseased patients. I sometimes perform periodontal surgeries for my patients, and the information I gather from the PreXion eliminates many surprises. Some argue that patients are exposed to too much radiation if you take a scan for less than a complex case. I calculated that a full mouth PreXion scan is similar to a cross country flight or about half the exposure of a mammogram, depending on your settings. I strongly disagree that this is too much radiation for the information one extracts. If a patient has never had a scan I often take one as part of our adult FMX. I don t repeat it every five years unless there is a compelling reason. A full PreXion scan shows the upper and lower jaws with the superior axial border usually showing three quarters to all of the maxillary sinuses. Fig. 1 One scan is usually enough to plan a full mouth implant case including sinus elevations. Some clinicians use a third party software to help analyze PreXion data. I really have found little use for it and I am happy with the diagnostic tools the machine comes with. As clinicians, we are responsible for diagnosing the images we take. That s another reason I like my PreXion, because I am very comfortable with diagnosing pathology in these areas, but some machines include much more unnecessary anatomy that the owner is responsible to diagnose. Occasionally I will send a scan to a professional radiologist, but this is the exception, not the rule. My assistant, Ampon, is amazing and has never failed to get an image on a patient, even on difficult very large patients. I think my PreXion images are better than any other CBCT and I would buy it again. If you are considering buying a CBCT I have a question you MUST ask before purchasing; How much is your yearly fee to receive software updates and warranty any repair work. The patient presented with missing upper molars bilaterally. The first premolar on the right side and the second premolar on the left side had severe bone loss and extractions were Fig. 2 Page 8 of 3D CBCT Report

9 and made a full thickness flap from the distal of the upper right canine to the area of the missing second molar with a buccal releasing incision. After removing soft tissue remnants, bone was collected from the lateral maxillary sinus wall with a bone scraper. After sufficient collection, the lateral window was created with the coronal margin ending about 3mm above the ridge. Fig. 3 planned (Fig. 1 & 2). She wanted to restore her chewing ability and agreed to sinus lifts with simultaneous implant placement. Traditionally the rule of thumb is that 4-5mm of alveolar bone below the maxillary sinus is a sufficient amount to predictably place implants while simultaneously performing the sinus lift. We chose to treat the right side first and come back later to treat the left. We chose a lateral window approach Next the Scneiderian membrane was gently reflected and surgical gauze soaked with 2% lidocaine with epinephrine was placed under the membrane to hold the space and protect the membrane from the implant drills. We then created our osteotomies leaving them undersized to insure primary stability. Next we placed a 50/50 mixture of autograft and Osteoblast (Keystone) into the medial area of the sinus. This ensures that bone is closely adapted to the far side of the implants as it is tough to place bone here once the implants are in place. Now the implants were placed (Fig. 3) with healing caps and the rest of the sinus was packed with the bone mixture. Studies show that lateral windows heal better with a membrane cover, so a 4 month collagen membrane was placed. Primary closure was easily achieved with 4-0 silk. 8 mgs of Dexamethasone was injected at the beginning of the procedure and the patient started antibiotics 48 hours before treatment and continued them for five days after. Healing was uneventful and sutures were removed at one week. This coronal section shows an implant in place with good bone adaptation on the right and the left side before treatment. The patient is now ready for second stage surgery on the left side and soon will have all her back teeth again. About Dr. Miller Dr. Miller graduated from the University of California at San Francisco School of Dentistry in 1996 and obtained his undergraduate degree in Biochemistry from The University of San Diego. He originally practiced in San Diego and currently owns Caring Dentistry of San Rafael in Marin County. His practice is focused on a comprehensive approach to preventative dentistry and he is committed to ongoing continuing education and adopting the most advanced technologies to provide his patients with the best care possible. Dr. Miller purchased his PreXion3D system in Page 9 of 3D CBCT Report

10 Interviews Shuichi Yamaguchi, DDS Everett, Washington When and why did you get into 3D CBCT imaging? While I am a General Dentist, my practice has been focused heavily on fixed and removable prosthodontics. Prior to purchasing my PreXion3D system in 2009, due to the limited information available to me using a panographic or a ceph x-ray, there were many cases that I either had to refer out to a specialist or used a very conservative treatment with removable dentures. Since getting my PreXion3D, I have been doing much more difficult and complex cases. Why did you end up purchasing PreXion over competing systems? While evaluating CBCT systems I was impressed with PreXion s high image quality, the responses from the PreXion personnel and based my purchase decision the enhanced diagnostic capability of those images and the confidence I had that I would receive good support. After using the system for more than two years I am still very happy with my decision and highly recommend PreXion. What have been the clinical and economic benefits of implementing a CBCT system into your practice? Once I started using the PreXion system I gained confidence in my diagnosis and treatment planning. The number of implant and fixed prosthodontics cases I was performing increased, my referrals went down as did the number of conventional denture cases. As a result of this technology, I am now doing as many as 200 implants a year. The 3D and MPR images make the diagnosis of abscesses easier and more accurate and also help me educate patients and increase rates of treatment acceptance. My patients are amazed when they see the images and it helps them understand their oral anatomy for the first time in their lives and why specific treatments were needed. When I would have historically taken a pano x-ray, I now do a 3D CBCT because the information I obtain is so much more detailed, accurate and useful. It helps me identify root fractures in endo cases and is invaluable for 3rd molar extractions. Another benefit of this technology is a reduction in my stress level making dentistry more enjoyable. About DR. Yamaguchi After completing dental school at Tokyo Dental College in 1978, Dr. Yamaguchi came to the United States for post-graduate training at Creighton University School of Dentistry ( ). Then he attended Kawabe Prosthodontic Institute in Tokyo from for advanced training in Fixed and Removable Prosthodontics. After graduating with a D.D.S. from Creighton University School of Dentistry in 1995, he started practicing in Everett. He attended the Misch Implant Institute at the University of Pittsburgh for advanced training in dental implants and completed the surgical and prosthodontic program in He is a member of the American College of Prosthodontists, the Academy of General Dentistry, a Diplomat of the International Congress of Oral Implantologists, has a Fellowship from the Misch Implant Institute and was Co-Author of Kawabe s Complete Dentures. Page 10 of 3D CBCT Report