What s sexy, what s strong

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1 What s sexy, what s strong Digital Dentistry The present and future of CAD/CAM restorations Fall 2010 Jack D Griffin, Jr DMD Diplomat American Board of Aesthetic Dentistry Accredited American Academy of Cosmetic Dentistry Master Academy of General Dentistry Thank you for choosing to spend your time with us. We know that there are many choices in continuing education and we sincerely want this to be one of the best experiences in dental CE today. Our goal is to help you gain greater understanding, confidence, and skill that will allow you to take your practice to the next level in restorative dentistry. Please let us know if there is anything we can do to help you in this experience as we learn to take your practice to a higher level with CAD/CAM dentistry. Don t limit yourself to only doing what you already know. Learn, experience, master, and challenge yourself to provide a new level of care that will stimulate you in your profession while providing your patients with terrific care. Success is where preparation meets opportunity. All materials in this manual are protected please don t copy without permission

2 CAD/CAM history Over 25 years ago Dr Werner Mormann placed the first CAD/CAM restoration in a live patient at the University of Zurich Dental School. The terms chunk of porcelain floating an a sea of composite were fairly accurate in the description of these early restorations. There were only crude inlays and crowns were only possible later. We have come a long way. His first CEREC (Chairside and Economical Restorations of Esthetic Ceramics) was revolutionary at the time as it some sort of camera, a computer, and a milling machine (in a single unit) to make a ceramic restoration chairside. As with all technology, improvements come with time. Fast forward to 2010 and we find almost every dentist using some sort of CAD/CAM (computer aided design/computer aided manufacturing) restorations in many clinical situations. Not only are there 2 complete chairside systems in wide use with CEREC (Sirona) and E4D (D4D Technologies), but there are many labs using systems like these to make your porcelain and metal restorations without your knowing. They take your impressions or models, make digital representations, and create restorations. Many bridges, implant abutments, surgical guides, and, of course, single units are made with this technology. The potential uses are almost endless. Back to CEREC. Since 1985 more than 27,000 units CEREC units have been installed in more than 50 countries. More than 20 million restorations have been placed. This technology has been studied more than any other dental restorative technique in history as there has been a wide amount of skepticism, much of it warranted. By now, we ve all seen some ugly stuff by in office CAD/CAM (more about my stuff later). First there was the limitation of the software. First there was an Everest steep learning curve that produced non-human looking teeth from a 2-dimensional computer monitor and then a milling chamber that created anatomy like a hung-over freshman dental student. All of this to produce weak porcelain restorations that seemingly broke while patients ate pudding. Then to top it all off was us dentoid personnel who had no clue in bonding, how to treat porcelain, or how to integrate the technology into practice. There should have been skepticism. Of course, things are much better today. History The system is manufactured by "Sirona Dental" in Bensheim, Germany Development of the CEREC method at the University of Zurich W. Mörmann, M. Brandestini) Treatment of the first patient with CEREC (University of Zurich, material: VITABLOCS Mark I) Siemens acquires the license to market and further develop the CEREC equipment CEREC 1 is introduced (chief indication: single and dual-surface inlays; material: VITABLOCS Mark II) International CEREC Symposium at the University of Zurich Hydraulic machining drive replaced by an electronically controlled motor CEREC 2 is introduced (range of indications: inlays, onlays, veneers) Sirona was formed as the result of the sale of the Dental Division of Siemens AG CROWN 1.0 program for producing full-ceramic posterior crowns Second material manufacturer partnership is formed (lvoclar, ProCAD) CROWN 1.11 program for producing posterior and anterior restorations CEREC 3 is introduced (compact Windows-based CAD/CAM system) Third material manufacturer partnership is formed (3M Paradigm MZ100) More than 2,500 CEREC users in the United States and over 5,000,000 CEREC restorations placed D software version is released, allowing users to see 3D views of teeth and models CEREC Celebrates 20 Years Sirona releases BIOGENERIC version of software. This software allows for the machine to accurately reconstruct the missing tooth shape and surface More than 23,000 CEREC users world wide Sirona release the MCXL milling unit, this milling unit can produce a crown in 4 mins Sirona release CEREC Acquisition Center (AC) powered by Bluecam 2

3 My History Sorry to bore you with this.it s not about me. It s about my patients. It s about my profitability. I have felt like a crash test dummy. CEREC 1 and 2 were terrible. I first had a CEREC 2 in 1999 while we waited for the CEREC 3 to be released which we received in We were designing things in 2 dimension chasing little red and blue dots around a dark back ground monitor which we did until 2003 when CEREC 3d was finally released. Imagination and thorough tooth morphology was needed by the dentist because the machine certainly didn t have it. We only had 3 types of blocks at the time: Vita porcelain, ProCAD porcelain, Paradigm composite. The highest flexural strength was 160MPa when stained and glazed and about 120MPa when just polished. That was not enough (regardless of what Dr Christensen and all those CEREC instructors told us). To make a very long story short, we placed over 10,000 restorations in an 8 year period with about 6% failure. To emphasize, that s about 600 restorations to replace! I ve had every software and hardware problem imaginable and have spent more money and time than you want to know. Would I do it again? Yes! I have felt like a crash test dummy. I ve learned a lot and hopefully have helped others not go through some of the stuff I ve suffered through. The CEREC 3d is what the CEREC 3 should have been like Window 7 is what Vista should have been. At this point, the new CEREC AC is what we should have been using several years ago. I will say this about Sirona, each generation of machine has brought great improvements in efficiency. And now with the CEREC club (for only $209 per month) your updates are included in the service agreement along with 50% off of some things you will need (like a new lens). Note that D4D doesn t charge anything for these updates but there is no discount for goodies either. What have I learned with all of this that I want you to take home with you? I think the following should help keep you out of trouble and frustration: 1. Before buying any technology, test drive it. See it used by someone who knows how and see if you can use it in your office for a period of time before buying. 2. Especially when considering the CEREC or E4D, remember that the initial cost is only part of it. Find out what the updates cost, maintenance costs are per hour, find out how fast a technician will be at your office when something fails, find out what the bumper to bumper warranty is. How much are blocks, oil, spray, etc. 3. Who do you like dealing with Patterson (CEREC) or Schein (e4d)? 4. When choosing porcelain, we are concerned much more with strength than looks. Don t replace any functional cusps with anything under 300MPa of tensile strength. (emax CAD, Zirconia) That includes the strength of the layering porcelain to the substrate. (Layer of porcelain to zirconia is only MPa) 5. Cement following proper porcelain techniques and only use a material that is proven to work that has some sort of dentin conditioner/primer like Multilink (Ivoclar) or Duo-Link SE Kit (BISCO) for better early bond strength. 6. Start with a system of digital impressions that can be expanded to include a design software and milling center like CEREC AC or E4D. 7. If you have more than 10 years left in practice, you might as well jump on board. 3

4 This course We have a short time together and there are many different levels of experience in this room. I m sorry if I talk about anything you feel is above or below your level of expertise I only try to cover all basics to exclude no one. Educational Objectives: 1. An overview and comparison of CAD/CAM systems for in office use 2. Who should and who should NOT consider owning 3. Rationale between in office or laboratory milling 4. The advantages of digital impressions and techniques for efficiency 5. Anterior and posterior preparations for success with all porcelain restoration 6. CAD/CAM restoration design and milling demonstration and discussion 7. Posterior restoration finishing...staining, glazing, polishing 8. Successful and predictable porcelain bonding About This Seminar: This course is intended to "de-mystify" the world of digital dentistry while reviewing various choices in digital impression taking, porcelain selection, preparations for success, and CAD/CAM fabrication. The techniques taught for preparation, porcelain selection, and cementation apply universally to other all porcelain systems. In office CAD/CAM systems such as CEREC and E4D restorations have gained great momentum because of advancements in computer software and ease in design. Dr. Griffin has been involved with CEREC CAD/CAM restoration education for over 10 years and has inserted over 10,000 restorations and teaches very clearly which techniques and materials have been successful and which have not. The basic concepts of this system for routine posterior restorations as well as customization of anterior teeth are covered in a very clear and entertaining fashion. Demonstrations of this technology will be done as time permits. A basic outline for this course is as follows. 1. The machine 2. The restorative materials 3. The finishing and cementing 4. The efficient use of chairside systems Who should do CAD/CAM dentistry? Every one! You frankly will have little choice. In order to be efficient, the labs will digitalize your impressions and models whether you want them to or not. Machine created restorations, if not done in your office, will be done in the lab. Customization will be what separates the quality lab from the junk lab. The real questions are the following: 1. Who should be taking digital impressions? It makes perfectly good sense for any office who wants to become involved in this digital dentistry to begin by only investing in a digital impression system and then to pay a lab to design, mill, and finish the restoration. Frankly, it takes the most aggravating part of the process, the milling machine, out of the picture for you. 2. Who should own design software and a milling machine? That is a much more complex answer. Don t listen when someone tells you it takes # of restorations to make it worthwhile. That s crazy. If you hate computers, have a staff that doesn t want to learn new technology, you like blaming the lab for all of your failures, and you already run an efficient office, 500 restorations a month won t pay off for you. (you see why I have no sponsorship with Sirona) What you have to decide is whether or not you can do better work for your patients in a more efficient manner. 4

5 The 2 major players in chairside CAD/CAM: CEREC - Sirona Sold in the US by Patterson Dental. Same major porcelain choices as e4d. Should use powder for better image detail as the image is captured by a blue LED (like LAVA). Can take multiple images and the machine will stitch them together. Milling machine has 2 diamond burs and 2 motors and mills on average a full crown in about 6 minutes. 25 years of intense scrutiny. (My choice because its all there was) Cost: $119,000 CEREC club $209 per month = free updates and 50% off some stuff E4D D4D Technologies Sold in the US by Henry Schein. Same major porcelain choices as CEREC. Powder not needed as the image is captured by a Red Laser (Like Cadent Itero). Remember, clearish enamel will not be read accurately by this camera either without powder. Can take multiple images and the machine will stitch them together. Milling machine has 4 motor and 4 diamond burs and mills a restoration in about 18 minutes. 2 years of scrutiny.however, same basic materials as CEREC. The delivered product shouldn t be much different. Cost: $116,000 Free updates for 3 years 5

6 Digital impressions: Obviously CEREC and e4d garner much of the attention but there are other systems to consider and a bunch more to come to market in the next couple of years. Digital impressions, in my world, can be used on 95% of single units, 75% of multiple units, and 50% of bridges. We do NO veneers at this point with digital images (higher quality veneers turn out better for us using traditional techniques). There are certainly viable advantages for digital impressions instead of traditional impressions. Accuracy no shrinkage, distortion, pulls, bite trays No gagging as long as the camera will fit in the mouth, it s fast and easy Immediate feedback can retake as many as you want for no cost if lousy Prep evaluation chance to see just how lousy you really are with bur, modify, recapture Free (?) no cost for impression material, adhesive, tray, opposing, bite registration Versatile Any type of restoration can be made temps, porcelain, metal, zirconia And certainly there are disadvantages as well. Subgingival the farther subgingival, the harder to capture a great image without laser Small mouth the height of the camera varies by company, second molars can be difficult Powder some systems use reflective media which must be applied evenly and rinsed well No Powder without reflective media accuracy can suffer for clearer enamel and corners $$$$$$$ - Will the initial cost of the gizmo and its maintenance outweigh impression stuff? Smarts and patience there is a definite learning curve, time and experience matters Some systems charge for every scan and model which the lab may absorb LAVA Chairside Oral Scanner (COS) 3M ESPE -- $26,900 3M has deep pockets and are investing heavily in this market. Expect this to prosper. Tooth is prepped and scanned in. Uses blue LED like CEREC to capture image. Small camera and easy to manipulate. Images are captured of both arches with buccal bite and sent via internet to lab. A scan fee to the office will be charged of $16-$20 per scan with a model fee of $16-$30. The powder is about $19 a bottle. itero Cadent - $25,000 Not such deep pockets here. Inside the computer a lab slip is filled out. Tooth is prepped and scanned in. The scanner is much larger than with other systems at this point. Uses red laser like e4d to acquire images. The image is sent via internet to lab. Slowest of all systems to capture images and largest of all the cameras. Both arches are captured and a buccal bite image is captured to relate the arches. The scan fee is $25 for a quadrant and $35 for a full arch and the model is $18-$31. Lab role: They are way ahead of most of us on this. Many of the restorations being made are CAD/CAM and many dentists placing them have no idea. Whether sending impressions or digital images of the prep, the lab has been using this technology. Check with your lab to see what CAD/CAM systems they are most familiar with. You will get the restoration back without a model unless you request it which adds more cost. This takes some experience and trust with the system and can be like a baby giving up a pacifier at first. 6

7 Perhaps one of the great ways get involved with this is to purchase a digital scanner and upload it to a participating lab. The restoration can be designed by the dentist and merely milled and finished by the lab or the lab can do the entire process. Like stated above, it may be an advantage to purchase a system that can be upgraded to include a milling center if desired later. CEREC allows direct lab communication with a lab via CEREC Connect as does e4d Sky. The choices often involve weather or not the lab makes a model which involves additional cost. The turnaround time by the lab figures to be less than with traditional restorations and the fee should as well be less. Porcelain choices: There are at least 4 choices in porcelain for in-office milling (: 1. Vitablocks Mark II feldspathic porcelain, ~120MPa polished, ~160MPa glazed, great add on porcelains, beautiful glazing, only for anteriors (if ever) now in our office, HFl etch 1-2 minutes, rinse thoroughly, silane, bond into place 2. Empress CAD leucite reinforced porcelain, slightly stronger than Vita, same formula as the wildly popular pressable Empress, inlays and non-functional onlays in our office, HFl etch 1-2 minutes, rinse thoroughly, silane, bond into place 3. Paradigm MZ100 composite, very nice material, cannot code as porcelain but may be good for those teeth you can t do porcelain on, will not maintain a high luster, sandblast, bond into place 4. IPS e.max CAD GREAT material, lithium disilicate, more than twice the strength, ~400MPa, milled in soft blue phase for ease on machine, must be crystalized in oven, should NOT be sandblasted, HFl acid etching for 1-2 minutes, rinse thoroughly, silane 1 minute, then bond into place STRENGTH Lithium disilicate Strong and Sexy There has been a MAJOR breakthrough with the invention by Ivoclar of e. max CAD it changed the world for us when it comes to full posterior crowns and replacement of functional cusps. With 600 failures out of 10,000 we had to do something. In fact, we were using the CEREC less and less because of porcelain fracture until it Ivoclar introduced this product. It is a nice monolithic block ideal for the CAD/CAM world. This material is extremely esthetic, strong, and versatile. It comes in a pressable form (IPS e.max Press) that many labs use. It can be cut back and added to or, most commonly, stained and glazed before inserting. Takes about 45 minutes total to shape, apply crystallization liquid, stain, bake, cool, and etch. That makes this a One Day restoration often in our office. After milling, we often try it in and then give the patient the choice to sit in chair, sit in waiting room, go somewhere else, and return in an hour. If they don t want to, we make a temp and try to have them back the next day. The Blue Block gets its name from the fact that the lithium disilicate must undergo 2 stages for crystallization. The first stage, pre-crystalization is done when the block is made resulting in lithium metasilicate crystals with a size of microns of about 40% volume. This creates a blue-violet color. This softer state allows for easy milling. The final crystallization occurs at 850 in a vacuum where the lithium metasilicate is replaced by disilicate crystals of about 1.5 microns of about 70% volume. It etches and bonds like any other porcelain (see below) and even has been used with success in several studies using traditional cementation with resin-modified glass ionomers (i.e. RelyX). It must be crystalized in an oven at We need a minimum thickness of 1.5mm, the inside of the crown should NOT be sandblasted, HFl acid etching for 1-2 minutes, rinse thoroughly, silane 1 minute, then bond into place. Cementation: 7

8 We use resin cements or self adhesive resin cements on all all-porcelain restorations. With zirconia, we use almost anything depending upon the retentiveness of the prep. Of course personal preference is the key here After using just about everything, we are sticking with 2 choices: 1. Duo-Link SE kit 2. Multilink Kit It is true that RelyX Unicem has no primer but has years of good research behind it. Certainly, this would not be a bad choice especially since they finally got a click dispenser. The preparation of porcelain doesn t change whether office made or lab made you just need to know what step your lab stopped on. Most labs have HFl etched and silanated the restoration prior to sending it to your office. But don t assume.ask to make sure. Porcelain preparation after milling or pressing: 1. Hydrofluoric acid etch for 1-2 minutes (same for all porcelains except zirconia) 2. Rinse well 3. Apply silane for 30 seconds, then dry 4. Try on tooth 5. Rinse thoroughly, alcohol on mirobrush wipe 6. Apply porcelain conditioner/primer/silane depending upon bonding system 7. Dry 8. Apply luting material Tooth preparation: 1. Control bleeding cord, laser, aluminum chloride, ExpaSyl, Traxodent 2. Clean thoroughly rinse, alcohol scub on microbrush, rinse again 3. Luting material directly on to tooth if inlay onlay or simultaneous build-up 4. Seat restoration hold firmly with finger 5. After initial set floss, clean up, floss again 6. Cure all margins 20 seconds from all angles 7. Check bite, finish, polish 8. Cure again 20 seconds each side Finally I want to summarize and counter the negativity I started with. I would never go back to taking impressions for all work again for anything. Despite the love-hate relationship over the years, I m absolutely convinced that digital dentistry and in office milling for routine posterior crowns is best for me and my patients. Should you consider it? Absolutely. Should you buy? That s very personal for every office and doctor no one can tell you one way or the other. However, don t be closed minded life is way too short. Success is where preparation meets opportunity. Educational experiences like this help give you the preparation needed to succeed when opportunity arises. Keep learning materials and techniques seem to change overnight and sharing the experience of other practitioners is invaluable. There are many terrific educational resources today commit yourself to a life time of learning. By sticking to an organized sequence of treatment and keeping meticulous attention to detail, every practitioner can experience great rewards in cosmetic dentistry. What a great time to practice. THANK YOU very much for listening during this presentation it is an honor to be able to share with you. Jack D Griffin, Jr DMD MAGD HUEsmilecenter@aol.com U HUwww.eurekasmile.comUH All materials in this manual are protected please don t copy without permission 8

9 Notes: All materials in this manual are protected please don t copy without permission 9