issn 2193-4673 • Vol. 1 • Issue 4/2020 4/20 digital international magazine of digital dentistry research The diode laser in a fully digital workflow case report Digital procedures for the design of a sequential occlusion interview How 3D printing has transformed dental care

editorial | Dr Scott D. Ganz Editor-in-Chief Holiday season 2020—normalcy We are now in the last month of 2020, and the outlook for 2021 is still not clear. The current pandemic still has a grip on countries around the globe, making it difficult to travel, host and attend educational meetings and symposia, or even visit with our family and close friends. We can only hope that help is on the way with vaccines that are effective and safe, allowing us to return to a sense of normalcy and confidence. In our world of den- tistry, we have always maintained a high level of infection control for our patients and staff, and we have always worn protective masks, shields and gowns. Of course, today, we are all taking extra precautions to ensure that we can deliver care in the most effective and efficacious manner. Therefore, dentistry will remain vital, important and essential to the health and welfare of the population worldwide. The COVID-19 pandemic has focused the globe on com- municating remotely, whether it is with our family or our colleagues. Our new normal may not allow for in-person meetings in the foreseeable future, which means that our educational opportunities will need to be visualised on a computer screen, tablet or smartphone. For many educators, this will require a somewhat different skill set, in terms of delivery, presentation materials, and the use of videos and animations which may or may not repro- duce satisfactorily, depending on the speed of internet or Wi-Fi connections. Additionally, it is an entirely differ- ent experience when one is presenting alone in a room facing a video camera where there is no direct feedback from what it is when speaking to a small group of clini- cians or from a larger podium at a major conference. Our educational experiences will therefore become a modified reality for both the recipients and those deliv- ering the content. Clinicians who were forced to close their practices may have elected to spend more time online reading and watching educational videos, gain- ing important insights from experts around the globe. Similarly, we might even predict that during government sanctioned lockdowns authors from around the globe may have taken the required time away from their offices to write new articles or textbook chapters or to prepare new lectures, videos or webinars. What has not changed are the numerous publications which will continue to deliver excellent content on a wide range of subjects, research and general interest topics. We are fortunate that the pages of our publications are made possible through a digital medium using software applications like Microsoft Word to compose the text and image editing software to prepare illustrations or clinical photographs for print or online presentation. All submis- sions are submitted online in a digital format. The articles are then compiled, reviewed, edited and then, once approved, sent for final layout to be approved prior to pub- lication. We are fortunate that even during the pandemic the various offerings from Dental Tribune International have continued to provide high-quality content of inter- est to our readership. We thank you for your patronage and appreciate your dedication to our chosen profession through our offerings. We also want to thank all of our incredible contributors, who spend countless hours documenting and preparing the manuscripts that you find within the pages of digital. Wishing everyone a very safe holiday season and a happy new year! Dr Scott D. Ganz Editor-in-Chief 4 2020 03

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research | 4 5 6 Figs. 4 & 5: Comparison of the impression without and with treatment of the sulcus shows that the use of the diode laser yields a clearer and more defined impression. Fig. 6: There is no significant gingival retraction one year after crown positioning. many laser-assisted therapeutic protocols have been reported in the literature, the laser-assisted full-mouth disinfection protocol1 is the one used in our daily clin- ical practice and is naturally adapted to the patient’s periodontal health status. In accordance with the guid- ing principles of technologically supported dentistry, our goal is to perform the tooth preparation and the optical impression in a single session. The absence of gingival inflammation is an essential condition. Therefore, a ses- sion of photodynamic and photothermic therapy a few days ahead is always recommended for a bactericidal effect. A 10 % povidone-iodine solution is placed in the gin- gival sulcus before inserting the fibre of the laser (PRIMO, MEDENCY), employing a pulsed mode of 50 micro- seconds on and 50 microseconds off for 30 seconds at a power of 2 W. Pre-impression troughing Many tooth preparation systems for one-piece com- plete-coverage crowns, bridges4 and veneers,5 like ver- tical preparation without a finishing line, are discussed in the literature. In our clinical experience, in order to obtain a good optical impression, a simple principle of tooth preparation must be respected when using an intra-oral scanner: juxta- gingival preparation in non- aesthetic areas whenever possible and minimal intra- sulcular preparation in aesthetically relevant areas. However, a minimal gingival displacement can help the dentist while taking the impression. Many studies on the evaluation of non-invasive gingival displacement systems are reported in the literature.6 The diode laser can be used for gingival displacement. While techniques involving gingival retraction cords or a diode laser lead to similar amounts of gingival retraction, use of the diode laser requires less time, is simpler for the operator and is more comfortable for the patient than are retrac- tion cords.7 Pre-impression taking with a diode laser does not create gingival retraction problems compared with use of a cord impregnated with aluminium chloride. The amount of recession has been reported as clinically insignificant for both techniques.8 A 980 nm diode laser is used with single- use fibres of 10 mm and 400 µ. The laser is set on a pulsed mode of 10 microseconds on and 10 microseconds off for 20 seconds at 2.2 W (Fig. 2). A single rapid and gentle movement of the activated fibre in the gingival sulcus is sufficient to achieve the desired result. The optical impression is taken with the WOW intra-oral scanner (Biotech Dental). Sometimes, a haemostasis treatment may be recommended to achieve the complete drying of the sulcus with a programme in continuous-wave mode for 20 seconds at 2 W (Fig. 3). Comparison of the quality of the impression without (Fig. 4) and with (Fig. 5) treatment of the sulcus showed that the use of the diode laser yielded a clearer and more defined impression. In accordance with the results reported in the literature,8 there was no significant gingival retraction one year after crown positioning (Fig. 6). Minor pre-impression surgery In some cases, minor gingival surgery is necessary for a good result of a prosthetic treatment. Modern dentistry, thanks to the use of advanced technologies, makes it possible by reducing the number of sessions and the in- convenience to the patient. A classic case is a subgingival partial fracture of a tooth that had undergone endodontic treatment at one time (Fig. 7). After tooth reconstruc- tion with a root fibre-reinforced post and composite, the use of a diode laser for minor surgical gingival correction is strongly recommended. The aim was to remove the excess gingival tissue and bring the fracture margin out- side the gingival sulcus (Fig. 8). The laser is used with single-use fibres of 10 mm and 400 µ, and the pro- gramme is set to a pulsed mode of 25 microseconds on and 50 micro seconds off, 6.5 W and an average power of 2.17 W. Its cutting performance without oedema and with immediate coagulation allowed for preparation of the abutment and impression taking in the same session. It is recommended to allow the gingival tissue to rest for 10–15 minutes between abutment preparation and im- pression taking. We use this time for the adaptation of a 09 4 2020

D A remove the healing screws and to position the crowns. Two screw-retained single zirconia crowns on Ti-base abutments were produced by the laboratory, checked by the practitioner and then positioned in the patient’s mouth. The occlusion, gingival health and points of con- tact were respected and the result was achieved in just two chair sessions (Fig. 14). The diode laser can be used effectively for second-stage implant surgery, providing both the dentist and the patient with additional advan- tages over the conventional methods used for implant exposure.12 Conclusion Modern dentistry is patient-centred in order to ensure maximal comfort to the patient throughout the whole treatment. Correct use of modern technologies to ad- equately address the patient’s needs and expectations through effective and high-quality therapies is the prin- ciple on which modern dentistry is founded. The goal is to achieve a minimally invasive treatment, which reduces the number and duration of chair sessions, overall dura- tion of the treatment and inconvenience to the patient. Technology that is correctly chosen and employed rep- resents a fundamental aid to achieving this desired result. The combined use of the diode laser in the ideal surgery and of the intra-oral scanner, supported by a specialist den- tal laboratory in a fully digital workflow, represents a way of achieving the aforementioned result in prosthetic dentistry. Editorial note: This article was first published in laser— magazine of laser dentistry, Vol. 11, Issue 4/2019. A list of references is available from the publisher. about Dr Carmine Prisco is an oral surgeon from Italy. He specialises in conservative dentistry, implantology, prosthetics and laser dentistry. Dr Prisco practises in his private dental clinic in Salerno. contact Dr Carmine Prisco Dental surgery clinic Salerno Italy carmineprisco@hotmail.it

case report | 4 2020 13 8 9 11 13 10 12 14

case report | 19 20 The articulator programming deriving from the axio- graphic record was then set as indicated by the software (GAMMA Dental Software), both for the regulation of the condylar and incisal guidance and for the adjustment of sagittal condylar inclination and Bennett angles (Fig. 21). The resulting prosthetic space, palpation during the visit, especially in the medial and lat- eral pterygoid muscles, reduced opening of the mouth and slight noise produced by the temporomandibular joints. Infection of the root of tooth #12, with 9 mm probing depths, was immediately attributable to a vertical frac- ture (Fig. 7). Once the fractured root of tooth #12 had been extracted, the patient would require fixed pros- thetic full-arch rehabilitation, providing for as few end- odontic and surgical procedures as possible. We agreed on a full-arch prosthetic rehabilitation that would allow, after studying the gnathological case and going through interlocutory therapy with PMMA interim prostheses, the definition of a sequential function at therapeutic refer- ence position through a controlled increase in VDO and stabilising jaw relations, then appearing conspicuously compromised. Therefore, cephalometric analysis was performed (Fig. 8) based on a lateral radiograph (Fig. 9), and axiography of border movements (CADIAX compact, GAMMA Dental; Fig. 10) was recorded to set up an average-value artic- ulator (Artex TR, Amann Girrbach), assembling stone models with the facebow, to mill first interim prostheses made at an arbitrary 5 mm VDO increase on the incisal rod and improvement of overbite and overjet, for an interlocutory pre-therapeutic purpose and immediate aesthetic resolution. Once the necessary causal periodontal and restorative therapy had been completed, an intra-oral scan of the arches (TRIOS 3 Pod, 3Shape; Figs. 11–14), and the jaw relations with reference position wax were recorded (Fig. 15). The scan images were printed in resin (VisiJet RWT white, 3D Systems) with detachable abutments using a 3D printer (ProJet MJP 2500 Plus, 3D Systems; Figs. 16–18). The resulting models were plastered to mounting blocks (Figs. 19 & 20) and mounted with refer- ence position waxes and a facebow in a fully adjustable arcon articulator (Reference SL, GAMMA Dental). 21 4 2020 15

case report | 28 31 29 30 32 33 (Xanos Evo Scan COMPACT, DENTAG; Fig. 24). The casts were thus imported in the correct spatial position into the CAD module (Virtual Articulator module, exocad Dental- CAD, exocad; Fig. 25). Not having the virtual analogue of the Reference SL articulator available in this CAD soft- ware, a virtual SAM articulator (SAM Präzisionstechnik) system was set, because both of them are designed on the same axioorbital reference plane and the geometry 34 36 35 37 4 2020 17

case report | 48 47 49 The sequential wax-up was scanned with a desktop scanner (inEos X5, Dentsply Sirona) and virtually captured. The vir- tual shape was rechecked in the CAD software for thickness, connection and morphology, and for offset adjustments for abutment adaptation. It was then sent for milling (CAM 5-S1) of second interim prostheses made of PMMA with high- stability ceramic micro-fillers (breCAM.multiCOM, bredent). The finishing of the dental abutments was followed by relining of the therapeutic reference position temporary restorations—previously having protected of all functional occlusal surfaces—and they were then finished and polished. Teeth #33, 42 and 43 were reshaped in the incisal area with direct composite additions, according to the morphology designed during functional waxing. 50 51 52 4 2020 19

case report | 62 63 65 This procedure can however be applied to any type of functional occlusion design—even canine-dominant oc- clusal function, group functional guidance or bilateral bal- anced occlusion, according to the clinician’s choices and experience. The enormous advantage of scanning the interim prostheses in therapeutic reference position after a trial period is evident: acquiring the details of the true function of the patient for the CAD analysis and check and for milling the permanent prostheses in suitable material. about Dr Mario Perotti obtained his MD and DDS from the University of Turin in Italy and MSc in digital dentistry from the University of Insubria in Italy. He manages a private practice in Turin and is a member of the research centre for innovative technology and engineered biomaterials at the University of Insubria. He lectures internationally on digital dentistry. Dr Perotti can be reached at drperotti@drperotti.it. Marco Marzolla is a master dental technician who specialises in CAD/CAM. He lectures on digital dentistry at the University of Insubria. Maurizio Melano is a master dental technician who specialises in occlusal functional waxing and assembling according to Prof. R. Slavicek’s school at Danube University Krems in Austria, where he attended a master course. 4 2020 21 61 64 Finally, we provided the dental impressions for the man ufacture of the permanent zirconia prostheses. The stone models were scanned with the inEos X5 and the data sent to DentalCAD (Figs. 47–49), and a sec- ond scan was done with the patient’s temporary res- torations positioned on the casts (Figs. 50–52). The CAD software allowed us to match the scans so that the one with the temporary restorations having been used in therapeutic reference position, with sequential occlusal function already completely programmed, was now used to define the permanent teeth’s morphology (Figs. 53 & 54) according to the planned jaw relations (Figs. 55–58). The permanent prostheses in zirconia (KATANA Zirconia UTML, Kuraray Noritake Dental) were then milled (CAM 5-S1; Figs. 59 & 60), and the dental technician performed the layering and the finishing. Finally, they were cemented by an adhesive procedure (PANAVIA V5, Kuraray Noritake Dental; Figs. 61–65). Discussion and conclusion The diagnostic and technical workflow for the design of a canine-dominant occlusal sequential function, inspired by that described by Prof. R. Slavicek, with the aid of the digital tools available today, proved to be convenient for the clinician and the patient, allowing a reduction in working time and procedural complexity. Time spent in the functional diagnosis and in the design of the sequential occlusion is in fact reduced, despite the absence of dedicated CAD tools, therefore requir- ing some repetitive CAD modelling procedures to be performed. The design of the obtained morphologies allows the project to be milled in different available materials as needed in shorter times and at lower costs compared with the traditional procedures. Further experience is needed for the refinement of an ideal pro- cedure, and suitable CAD tools should be developed for the purpose.

case report | 6a 6b Figs. 6a & b: Two 3D-printed templates designed on the digitised model (green): one for the initial drill to section the tooth at the root apex (a) and the second for using sequential guided drills to drill through the root itself (b). “Triangle of Bone” concept and specific instrumentation to achieve successful outcomes.5 The ability to perform the procedures requires care- ful diagnosis, treatment planning and excellent control of the drilling process to ensure that the root fragment will be maintained while maximising implant stability. In many cases, it may also be possible to provide imme- diate transitional restorations when high implant stability is achieved. However, complications can also arise when the root fragment is lost or the implant fails to integrate. It should be noted that PET has mainly been accomplished with a diagnostic freehand method for sectioning roots, osteotomy preparation and implant placement. The cur- rent article describes methods of providing PET proce- dures using full-template guidance based on a thorough appreciation of the existing anatomical structures utilis- ing advanced state-of-the-art treatment planning tools, 3D design software, 3D printing and/or CAD/CAM sur- gical templates. 7a 8a 7b 8b Fig. 7a: A sleeveless guide to accommodate a 2 mm long pilot drill that was used to reach the root apex. Fig. 7b: Removing the guide allowed for inspection of the drill embedded within the tooth. Figs. 8a & b: Using drill guides with long shanks to engage the sleeveless template allowed for sequential and accurate drilling of the tooth and subsequent bone for implant placement. 4 2020 23

case report | 15a 15b 15c Fig. 15a: The base template was designed to seat firmly on the adjacent teeth, incorporating buccal and lingual hexagonal offsets to engage the different drill guide inserts. Figs. 15b & c: Separate inserts were fabricated for the initial drill guide to reach the root apex to accommodate sectioning, followed by a second guide for final osteotomy drilling and implant placement. fully appreciate the trajectory through the clinical crown (Blue Sky Plan, Blue Sky Bio). It is important to visualise the root fragment that will remain in order to properly sim- ulate the position of the implant in the alveolus (Fig. 3b). The apical portion of the implant can be positioned to gain stability in host bone using the Triangle of Bone. It is important to note that a cross-sectional slice may only be 0.125 mm in thickness based on the CBCT ac- quisition, and therefore all images in all views must be visualised to confirm the plan. Utilising 3D segmentation (separating objects by density values), it is possible to define each root and further assess the simulated posi- tion of the implant with a sagittal cut through the 3D re- constructed volume (Fig. 4). The ability to export volumes in STL format allows these objects to be edited and utilised in other software appli- cations, such as Meshmixer (Autodesk). The STL file of the root image was imported into Meshmixer, and the root was virtually sectioned using Boolean difference to mimic the crescent shape for PET (Fig. 5a). The apical portion of the simulated implant can then be positioned so as not to touch the root fragment while engaging in host bone for stability (Fig. 5b). Planning with such precision is predicated on the acqui- sition of a satisfactory CBCT scan with a proper field of view and the incorporation of occlusal surface data STL files of the arch form, digitised through either an intra-oral scan or a desktop scanner imported into the software. Two 3D-printed templates were then designed on the accurate digitised surface model, one for the initial drill to section the tooth at the root apex and the second to use sequential guided drills to drill through the root itself (Fig. 6). A 2 mm pilot drill, which was long enough to reach the root apex with the tooth-borne surgical guide in place, was utilised with a sleeveless guided approach (Fig. 7a). Removing the guide allowed for inspection of the drill through the tooth (Fig. 7b). Using guided drills with long shanks in a sleeveless guide allowed for sequen- tial and accurate removal of the tooth and subsequent bone beyond the apex of the natural tooth root (R2Gate, MegaGen; Fig. 8). The cylindrical tooth preparation/oste- otomy resulted in the desired crescent shape to provide space for the implant (Fig. 9). The root was then sectioned mesiodistally using specialised drills (Root Membrane Kit, MegaGen) and the palatal section removed. Utilising 16a 16b Figs. 16a & b: The accuracy of the implant and template design allows for true restoratively driven planning combined with CAD/CAM applications for the design and fabrication of a patient-specific abutment and transitional restoration. 4 2020 25

case report | 26a 26b 26c 26d Figs. 26a–d: The prefabricated CAD/CAM abutment and transitional crown (a). A post-op periapical radiograph confirmed successful sub-crestal placement of this platform-switched design (b). The abutment in place (c). The soft-tissue contours were excellent; no sutures were required for the transitional restoration (d). the template, the implant was placed into the osteotomy using the correct implant carrier to achieve full-template guidance and stability measured using resonance fre- quency analysis (RFA) to obtain the implant stability quo- tient (ISQ; Fig. 10). tooth-borne guide); (2) a pilot drill guide for the root apex (APEX STACK); (3) a crescent-shaped guide for shaping root fragments (PET Shaper STACK); and (4) a guide for osteotomy drilling and placing the implant through the guide (Surgical Guide STACK; Fig. 11). The concept of drilling through the root is not new and has been reported in the literature.8 Using guided meth- ods for the socket shield technique has also been re- ported using a CAD/CAM-fabricated template.9 However, the ability to use technology to plan and execute a fully guided procedure for a PET, socket shield technique and root membrane technique illustrates additional method- ology to aid clinicians in successful outcomes. The first concept described the use of two separate templates, one for separating the root at the apex and the second for drilling through the tooth and placing the implant. Continuing the evolution, we present a second option, which does not require the removal of the base template, but has inserts to allow for the different drills and angulation required for the PET technique: the stack- able tooth-borne guide. The new technique has four separate components: (1) a base template (stackable Case report A 62-year-old male patient presented with a hopeless prognosis for a post fracture in the left central incisor requiring extraction (Figs. 12a & b). The preoperative peri- apical radiograph revealed an existing implant support- ing a metal–ceramic restoration for the adjacent region #11 (Fig. 13). The CBCT (CS 9600, Carestream Dental) cross-sectional image revealed a favourable preoperative condition relating to the trajectory of the endodontically treated root to the alveolus for a PET procedure (Fig. 14a). Using the native Carestream 3D Imaging software, a simulated implant and abutment projection was posi- tioned within the available bone to avoid the root frag- ment (Fig. 14b). The final positioning of the implant, as determined by the restorative requirements, and design and fabrication of 27a 27b Figs. 27a & b: The post-op CBCT scan axial view revealed the intact crescent shape of the root membrane (a), as outlined in red in facial to the opaque implant position (b). 4 2020 27

case report | (AnyRidge, MegaGen) was facilitated by the R2Gate surgical carrier for full-template guidance at the appropri- ate torque values (Fig. 23). Depth control and rotational positioning were accurately confirmed with the notch indicated on the template to correspond with the inser- tion tool (Fig. 24). The initial plan was for immediate extraction, immediate placement and immediate restoration. Therefore, it was essential to measure the implant’s stability with an objec- tive technology, RFA, which provides an ISQ value util- ising an implant-specific SmartPeg (Osstell; MEGA ISQ, MegaGen). The baseline ISQ value (76) confirmed suf- ficient initial stability to place an immediate restoration (Fig. 25). The prefabricated CAD/CAM abutment was then secured to the implant, and a postoperative peri- apical radiograph confirmed successful sub-crestal placement for this platform-switched design (Fig. 26a). The transitional acrylic restoration was then placed and examined for any occlusal interferences (Fig. 26b). It was important that the restoration be out of occlusion to avoid premature forces that could complicate inte- gration. The soft-tissue contours were excellent, and no sutures were required, since no flap was raised (Figs. 26c & d). After a period of eight weeks, the im- plant stability was measured to be at 80 ISQ, confirming that the integration process had continued to progress successfully and that the implant was ready for the de- finitive restoration. An intra-oral scanner and scanning abutment were then utilised to capture the position of the implant and soft-tissue emergence profile. The post - operative CBCT scan revealed the intact crescent shape of the root membrane (Figs. 27 & 28). The definitive restoration was then delivered and exhibited excellent retention of the soft-tissue profile (Figs. 29 & 30). Conclusion PET, root membrane and socket shield concepts have gained popularity as the techniques have been refined and their efficacy proved in published long-term stud- ies. The purpose of retaining the root is to maintain the periodontal ligament attachment to the bony walls of the socket in order to prevent subsequent resorption and loss of tissue volume which often occurs after tooth ex- traction. PET has been proved to preserve bundle bone and tissue volume with and without immediate implant placement, yet this minimally invasive treatment modal- ity is highly technique-sensitive and may result in com- plications if proper protocols are not followed. Therefore, a complete understanding of the 3D anatomical presen- tation is essential for preliminary diagnosis, treatment planning and execution of the procedure. The present article has described two alternatives that maximise the diagnostic phase using state-of-the-art CBCT imaging and planning software to provide full-template guidance with a new stackable tooth-borne guide with specific in- serts for the root preparation as well as the osteotomy preparation and delivery of the implant. As with most techniques, further clinical trials are recommended to provide additional long-term data to validate these treat- ment modalities. Acknowledgement: The authors would like to thank Dr Barry Kaplan of Morristown in New Jersey in the US for his expertise and assistance in the preparation of this article. Editorial note: This article originally appeared in Dentistry Today in September 2020, and an edited ver- sion is provided here with permission from Dentistry Today. A list of references is available from the publisher. about Dr Scott D. Ganz received his specialty certificate in maxillofacial prosthetics and prosthodontics, and this led to his focus on the surgical and restorative phases of implant dentistry and his subsequent contribution to 15 implant-related textbooks. He is a fellow of the Academy of Osseointegration, a diplomate of the International Congress of Oral Implantologists (ICOI), US ambassador of the Digital Dental Society, president of the US branch of the Digital Dentistry Society (DDS) and a co-director of Advanced Implant Education (AIE). Dr Ganz is on the teaching staff of the Rutgers School of Dental Medicine in Newark in New Jersey and maintains a private practice in Fort Lee in New Jersey. He can be reached at drganz@drganz.com. Dr Isaac Tawil sits on the Digital Dental USA Society Board of Directors, and is a diplomate of the International Academy of Dental Implantology, the IADFE, a fellow of the Advanced Dental Implant Academy, and the ICOI. He is one of Dentistry Today’s Top Leaders in CE, a faculty member of the Osseodensification Academy, Brighter Way educational director (Phoenix, Arizona), and digital director of Guided Smile. Dr Tawil is an ambassador of MegaGen International Network of Education and Clinical Research, a member of MINEC USA and an ambassador for the Slow Dentistry initiative. A recipient of the Pierre Fauchard award and the Presidential Service Award for outstanding achievements in dentistry. He is the founder and co-director of Advanced Implant Education, a partner in TBS instruments, and Universal Shapers LLC, and a new product consultant for dental industry. Dr Tawil has held main podium sessions and workshops globally and maintains a private practice in Brooklyn, New York. He can be reached at iketawil@mac.com. 4 2020 29

case report | 5 6 nor staged bone grafting (Fig. 4). Bone density was Type 2 according to the Leckholm and Zarb classification. important anatomical points, prosthetically driven implan- tation was planned, taking account of the available bone volume and the soft-tissue profile, using coDiagnostiX. The SAC Assessment Tool was used to identify the de- gree of complexity and potential risks involved in this case. Because of an immediate loading protocol and the other modifiers, this case was determined to be advanced (Figs. 5 & 6). Treatment planning After discussing different treatment alternatives, we de- cided on immediate loading with a fully digital workflow to deliver a digitally produced temporary crown on the same day of surgery. For the education programme, diagnostic cast models were prepared in advance by the mentors, and scanned STL data was given to the mentees (Figs. 7 & 8). These STL files were imported into coDiagnostiX, where DICOM images from the patient’s CBCT scan were seg- mented and merged. After segmenting and landmarking 7 8 A Straumann Bone Level, narrow-necked, Roxolid, SLActive implant was selected (diameter: 3.3 mm, length: 10.0 mm; Fig. 9). The surgical guide was designed with a sleeve of 5 mm in diameter and 5 mm in height. This guide design was sent to the laboratory and printed using the Straumann CARES P30 printer. 9 4 2020 31

case report | 18 20 19 21 22 crown was sent to the third-party dental laboratory and manufactured using PMMA blocks (Sigmadent). Self- adhesive resin cement (Multilink Speed, Ivoclar Vivadent) was applied to the Straumann Variobase, and the temporary restoration was bonded extra-orally. After polymerisation of the resin cement, excess cement was removed from the Variobase–temporary crown complex, and the lower mar- gin of the crown was polished. The temporary crown was placed on the implant and tightened by hand (Figs. 20 & 21). After adjustment of the contouring and the occlusion of the crown, a small cotton plug was inserted into the screw access channel. The occlusion required only minor adaptations owing to accu- rate digital preoperative planning. The rest of the channel was filled with a temporary filling material. The provisional implant restoration was worn for three weeks to allow proper recontouring of the soft-tissue com- plex (Fig. 22). After three months, the patient was still content with the aesthetics and function of the provisional restoration and ready for the definitive restoration (Figs. 23 & 24). 23 Treatment outcomes A fully digital workflow—digital planning, guided surgery, digital impression taking, CAD/CAM of a temporary crown for immediate loading on the day of surgery—has three main advantages, if properly selected, planned and applied: reduced chair time, exploiting all the potential anatomical and biological conditions, and presenting the patient with a perfectly acceptable prosthetic rehabilitation in one day. The total treatment time and the number of surgical procedures are also reduced. The expectation of a successful outcome with this treatment protocol relies on two basic principles: proper indication and sufficient primary stability. Factors affecting primary stability, such as implant design, drilling protocol, bone den- sity and morphology, should be taken into consideration before deciding to proceed with this treatment protocol. 24 about Dr Ferit Bayram received his DDS and PhD from Marmara University in Istanbul. He is currently practising at the same university in the Department of Oral and Maxillofacial Surgery and continues his academic work, which focuses on oral surgery, advanced implant surgery and orthognathic surgery. 4 2020 33

industry report | 4 5 is easily overcome by designing two milling sprues per crown or bridge unit. on the aesthetic appearance of KATANA restorations (typically, white spots on the surface). Computer-aided manufacture Is wet or dry milling the best option for processing KATANA Zirconia Block? The best results are obtained with dry milling. This pro- cedure also leads to time-savings, as there is no need for drying after processing. When opting for wet milling, are there any particularities that need to be respected for KATANA Zirconia Block? Those users opting for wet milling and utilising the same machine for the processing of zirconia and glass- ceramics should implement a system utilising three water tanks (Fig. 3). One tank is filled with rinsing water, the tank used for processing of glass-based ceramics is filled with water and additives (such as Dentatec, Dentsply Sirona) and the one used for processing of zirconia is filled with purified or distilled water without any additives. Moreover, a prerequisite for a high quality of the man- ufactured restorations is that the machine has to be cleaned thoroughly every time before a different ma- terial is processed (Figs. 4 & 5). The following compo- nents need to be cleaned: – the milling tools; – the interior of the machine; – the water tank(s); and – all the filters. When is it necessary to replace milling tools used for the processing of KATANA Zirconia Block? It is recommended to replace the toolsets every ten to 15 units. At this time, the degree of tool wear amounts to approximately 50 %. Those who continue using the tools accept an increased risk of weakening the oxide ceramic’s microstructure: worn milling tools are likely to produce microcracks and microchipping. When these defects occur between the different units of a bridge, they increase the risk of chipping and fracture. Manual post-processing Are there any specific measures to be taken when removing the block from the machine? When machining is completed, the restoration should be touched only by individuals wearing gloves. Even after thorough washing, bare hands will release fats, which may lead to smear formation and a reduced translucency of the oxide ceramic material. How are the restorations cleaned after sprue removal? Powder residue should be removed after processing with a gentle stream of air. Alternatively, a fine (and obviously clean) brush may be used for the removal of the zirconia dust. Powder residue remaining on the restoration surface might lead to the occurrence of white spots or to smear formation. Steam cleaning of the restoration should be avoided, as this measure dramatically increases the pores in the material and alters the material properties. Typically, zirconia reacts to milling additives (Dentatec) in the water with a reduced translucency, so their use cannot be recommended. Residue of glass-ceramic particles found on milling tools, in the water or in the interior of the machine might also have a negative impact When is the right time to add fissures and texture to the sur- face of the restoration, and how is this task accomplished? Ideally, all those details that cannot be incorporated by a milling machine (surface texture, fissures, etc.) 4 2020 35

industry report | What measures should be taken to avoid discoloration of a restoration during sintering? Discoloration (usually leading to a green-yellowish ap- pearance) might be the result of contamination of the sintering furnace with metal oxides. These metal oxides originate from other materials processed in the furnace. They are released during sintering and absorbed by the restoration. Running a decontamination program on a regular basis is an effective measure to help prevent discoloration. For this purpose, white zirconia (either collected from odds and ends of non-shaded blanks or purchased) is placed in the furnace chamber and a sintering program is started. As the CEREC Speed- Fire furnace (Dentsply Sirona) does not offer a specific decontamination program, the user simply creates two separate jobs for the sintering of two single crowns, but sinters them together. The second job is used for the decontamination cycle. During this procedure, the white zirconia absorbs the metal oxides, which has a cleaning effect on the furnace. Characterisation Which techniques are best suited for optical refinement of monolithic restorations made of KATANA Zirconia Block? A material designed for this kind of refinement is CERABIEN ZR FC Paste Stain (Kuraray Noritake Dental). The paste-like shading solutions are filled with ceramic particles. Therefore, the optical effects achievable with these pastes are much more durable than those obtained with classical stains. As all the pastes are fluorescent, it is possible to produce a natural long-term fluorescence effect without an additional work step. With just four shades of the liquid ceramic—A+, Grayish Blue, Value and Clear Glaze—it is possible to perfectly character- ise 85 % of all restorations made of KATANA Zirconia Block. The firing temperature is 750 °C, and the coeffi- cient of thermal expansion values of CERABIEN ZR FC Paste Stain and KATANA Zirconia Block are precisely adjusted to each other. The product is also very well suited for glass-ceramic characterisation (Fig. 8). How can the restoration be held during characterisation? The easiest option is the use of putty material on a carrier. The crown is simply placed on the unset putty and then positioned on the carrier. The surface of the restoration should be cleaned with a gentle stream of air before applying the pastes. Thanks to the ceramic particles in CERABIEN ZR FC Paste Stain, the pastes stay put during processing and do not flow away. Polishing How does one ensure a low wear of the antagonist? Zirconia stands out owing to its hardness, which makes careful polishing of the surface a prerequisite for clini- 9 cal use. After characterisation with CERABIEN ZR FC Paste Stain, polishing of all occlusal contact areas is mandatory as well. The KATANA Twist DIA polishing set (Kuraray Noritake Dental) even allows for intra- oral use. “Zirconia restorations are subject to volumetric shrinkage (approximately 20 %) during sintering.” Placement What kind of resin cement is recommended for the definitive placement of restorations made of KATANA Zirconia Block? The best possible results are obtained with PANAVIA V5 (Kuraray Noritake Dental; Fig. 9). This adhesive resin cement system is responsible for the development of a particularly strong bond between the tooth structure and the restoration, and this also has a strengthening effect on the restoration. about Mathias Fernandez Y Lombardi is EU scientific manager of dental ceramics and CAD/CAM materials at Kuraray Europe. He may be contacted at dental.eu@kuraray.com. www.kuraraynoritake.eu 4 2020 37

can be combined, which results in fewer sessions. This benefits the treatment team and the patient, for whom the basis for decision-making becomes more transparent. What does digital dentistry mean to you? Steiner: Digital dentistry means to us a maximum inte- gration of all the digital process steps for dental rehabi- li tation. The main part deals directly with the patient: covering anamnesis, diagnostics, consultation, planning, design and production. In our opinion however, digital dentistry is also involved in upstream and downstream processes, that is, in procurement, logistics, data collec- tion, data security, data processing and documentation. The DEDICAM brand has taken a new direction with “ Digital Concepts”. What does this mean? Elbel: At BioHorizons Camlog, we have consolidated our digital segment in the department of digital dentistry. With DEDICAM in Europe and Vulcan in the US, we offer our customers holistic concepts to help them attain the next level of efficacy. As a result of the increasing com- plexity of the digital workflow, many users wish for simple and reproducible solutions—in other words: digital concepts. We bring these digital concepts to life individ- ually together with our customers. Steiner: We support surgeons, prosthodontists and den- tal technicians in their daily business with products and services to enable operating a seamless digital workflow throughout the process chain. Over the years, we have cultivated this with DEDICAM prostheses and will now in- creasingly drive this within the dental network. Success- ful concepts are above all characterised by the quality of cooperation between partners. This has to be transferred to the digital world. We offer support during implementa- tion, which may also have an impact on business orienta- tion. Possible examples are the Munich implant concept and COMFOUR for the rehabilitation of edentulous jaws. What makes DEDICAM unique? Steiner: Our customers are free to decide which services they wish to use and to what extent. Flexible entry and exit during the entire process are reminiscent of hop-on, hop-off buses, which will no doubt bring back memories of exploring a city in the past for some. This means clear concepts at maximum flexibility. We give companies the choice. It is important to us that no user feels trapped in a system or process. It is therefore open to every customer whether and to what extent we support him or her im- plant planning. The virtual model data set created on the basis of planning can be processed further by the scan and design service or by another partner. Afterwards, we take over manufacturing of the designed construction data set or someone else does. With regard to the portfolio of materials and constructions, we offer a broad range which leaves almost nothing to be desired and which is available in the accustomed CAMLOG quality. With DEDICAM in Europe and Vulcan in the US, we offer our customers holistic concepts to help them attain the next level. Elbel: Our aim is not simply to obtain as many orders for prostheses as possible. With our services, we would like to reach out to all protagonists of the implant den- tistry disciplines as partners at eye level and offer sup- port, know-how and technologies where necessary. The objective is to integrate BioHorizons Camlog’s implants into the digital workflow in the best possible manner and thus create added value. “It is important to us that no user feels trapped in a system or process.” What are the benefits for users when outsourcing parts of their processes to DEDICAM? Steiner: A major advantage is the combination of out- standing product quality and excellent service with constant optimisation of the overall portfolio. What our customers profit most from is the time they gain by out- sourcing to DEDICAM. Depending on the business orien- tation of a practice or a dental laboratory, this is a relevant factor. Whenever certain areas are outsourced, more in- ternal resources always become available, which in turn can be invested in work which cannot be covered by a service provider, such as the implantological work of the surgeon or the aesthetic finishing by the dental technician. Elbel: The high requirements and established standards in the Germany, Austria and Switzerland region also meet with international acclaim. Consequently, we are working on establishing our concepts internationally to support customers all over the world as partners. When choosing a partner, it is important to be able to rely on each other, especially when considering the rapid development of technologies and concepts. 4 2020 39

interview | “Digital dentistry also the captured patient data quickly and easily for different indications. supports patient communication, as the dentist can easily use software for demonstrating the desired end result before starting the actual treatment.” Why should dental professionals go digital—and who would you recommend it to? General practitioners, dental specialists and techni- cians as well as dental hygienists can all benefit from digital workflows. With CAD/CAM technology, a dental clinic can offer its patients new services and better treat- ments—even during a single visit. CAD/CAM allows den- tists to design and manufacture inlays, onlays, crowns, veneers, bridges, dental implants and surgical guides in-house and to plan orthodontic treatments and maxil- lofacial surgery directly in the clinic. Digital dentistry also supports patient communication, as the dentist can easily use software for demonstrating the desired end result before starting the actual treatment. As I see it, the increased predictability of treatment is one of the most important benefits of digital dentistry. I believe CAD/CAM technology will become more com- mon even when performing dental check-ups. For ex- ample, digital impressions can be used to capture the patient’s current oral health condition and for treatment follow-ups. Why should a dental professional choose Planmeca’s CAD/CAM solutions? Going digital can be a big step for a dental professional. However, there is nothing to be afraid of—it is not even necessary to digitalise the complete treatment workflow at once. One can easily start by taking digital impressions and integrate the intra-oral scanner with other Planmeca devices later. The open Planmeca ecosystem allows dental professionals to proceed at their own pace. I worked with another dental equipment manufacturer for several years, so I know other systems well too. What distinguishes Planmeca is the unique Planmeca Romexis software platform. It is the biggest competitive advantage for clinics as well, as it integrates all different workflows into a single software program, making dentists’ work remarkably easier and allowing them to treat more patients in less time. With Romexis, dentists can utilise The integration of different devices with one another has a great number of benefits, starting from the compatibility of different data. However, purchasing all dental equip- ment from one manufacturer does not automatically mean that all collected patient data actually works to- gether without any problems. In this regard, Planmeca’s complete solution is indeed unique, as all Planmeca de- vices are connected to a single software platform, guar- anteeing seamless compatibility of the different data. This way, CBCT and CAD/CAM data can be easily and seamlessly combined in Romexis without error-prone and time-consuming data transfers. Additionally, all treat- ments can be planned and designed in Romexis, so no separate software is needed for different workflows, and as a result, the personnel do not need to learn to use mul- tiple software programs. However, all Planmeca solutions are open and thus compatible with other services, such as orthodontic applications, which means dental profes- sionals can work exactly as they prefer, if they choose Planmeca. You have been following the development of CAD/CAM technology for over ten years now. What does the future of dentistry look like? I believe that workflows will be digitalised to an even greater extent in the future. Both dentists and patients benefit from automated workflows, which reduce the risk of human error, increase the quality of the treatments and make the work more efficient. The digitalisation of workflows is happening all over the world, and Planmeca Romexis offers excellent tools for this. “I believe that workflows will be digitalised to an even greater extent in the future.” At the moment, there is already a clear consensus on the benefits of guided implant treatments among dentists, so they will become more common in the near future. Implants and surgical guides will be increasingly fabri- cated chairside so that dentists can treat their patients even faster and more safely. In addition to implantology, I believe guided treatments will become the standard for other indications as well. For example, I believe guided root canal therapy based on radiographic and CAD/CAM data will become more common soon. 4 2020 41

interview | 3D printing is a powerful technology on its own, but the real impact comes from the people who use it. We see new 3D printing applications all the time, whether they are born of necessity or innovation. That is why Formlabs is committed to increasing access to powerful digital technology. What are some of the criticisms of dental 3D printing, and do the benefits offered by using 3D printing out- weigh the associated risks? Ten years ago, the biggest problem with 3D printing was the prohibitively high cost of a printer. Luckily, with the success of manufacturers such as Formlabs in the mar- ket, printers are more affordable, more reliable and easier to use than ever before. Now, the only risk lies in having false expectations. A 3D printer is a piece of equipment, and learning to use a desktop unit like the Form 3B is easy, but it does take some time. Those who choose to adopt digital technol- ogy should embrace the learning curve, ask for advice from their peers and seek out professional development opportunities. Moving forward, 3D printing needs to overcome the den- tal industry’s skepticism about novel printing materials and applications such as printed dentures and perma- nent restorations. Manufacturers like Formlabs need to be proactive about teaching experts and validating new technology in the industry in order to achieve a mindset shift. But it will eventually happen. We have already seen it many times in the dental industry. Implants, zirconia, intraoral scanners, chairside milling and many other ma- terials and technologies overcame the initial skepticism. I am glad to be part of the movement that is leading and revolutionising digital dentistry. Georgio Haddad, dental strategic partnerships and initiatives lead at Formlabs, a 3D-printing technology developer and manufacturer. (Image: © Georgio Haddad) “3D printing is a powerful technology on its own, but the real impact comes from the people who use it.” Editorial note: The Formlabs Dental webinar, titled “Revo- lutionizing digital dentistry with 3D printing—accessible solutions and new applications,” is available on demand at www.dtstudyclub.com. Registration is free of charge. Formlabs’ Form 3B printer. (Image: © Formlabs Dental) 4 2020 43

news | ratory after virtual surgical planning. The remaining patients each received a prosthesis that was designed by a surgeon and 3D-printed via the in-house laboratory. The researchers fabricated a dental prosthesis using point- of-care 3D printing within 24 hours of the virtual surgi- cal planning session. The time required to generate the in-house 3D-printed prostheses was significantly shorter when compared with dental laboratory-fabricated prosthe- ses, which typically take weeks. Additionally, the procedure was more cost-effective. Whereas the prostheses created by an off-site dental laboratory averaged $617.00, each in-house 3D-printed prosthesis cost an average of $8.34 for resin, and the researchers noted that a full-arch pros- thesis 3D-printed in NextDent Micro Filled Hybrid costs under $50.00. The price includes the costs for the resin and the export fee for Blue Sky Plan, a 3D-printing software. “The study describes a digital workflow to design and 3D-print an immediate provisional dental prosthesis to be placed during jaw reconstruction when using a fibular free flap. This surgery has been called ‘Jaw in a Day.’ Previous methods involved third-party dental laboratories which require additional time, laboratory expertise and are more expensive. Our technique allows surgeon-guided virtual planning, just like we do with the jaw and fibula,” Dr Fayette C. Williams, fellowship director in the Division of Maxillofacial Oncology and Reconstructive Surgery at John Peter Smith Health Network, told DTI. “Creating a 3D-printed dental prosthesis in-house allows more control for the surgeon to create the occlusal scheme. It is also much quicker. I can generate this prosthesis in one day, whereas dental laboratories can take two or more weeks,” he added. According to the researchers, outsourcing dental prostheses to a dental laboratory has previously created a delay in the treatment, which has limited its usefulness to benign condi- tions. In the present study, the digital workflow used allowed for immediate dental restoration for patients with malignant disease. “This time is significant for a patient with cancer waiting to get their surgery to remove their jaw and tumor,” Williams explained. Despite its clear advantages, the re- searchers believe that the digital workflow presented in the study is most suitable for patients with teeth in place pre- operatively that will be removed with their tumor. For more complex cases, it is necessary to familiarise oneself with image manipulation and prosthesis planning. Additionally, the researchers calculated that the total initial cost of a 3D printer and post-processing supplies can reach around $3,000.00, plus additional costs associated with using the software. Editorial note: The study, titled “Immediate teeth in fibulas: Planning and digital workflow with point-of-care 3D printing,” was published on 1 August 2020, in the Journal of Oral and Maxillofacial Surgery. m o c . k c o t s r e t t u h S / n k e k e e b © i l “The time required to generate the in-house 3D-printed prostheses was signifi cantly shorter when compared with dental laboratory-fabricated prostheses (...)” A recent study found that printing dental prostheses for fi bula and implant reconstructions in-house eliminates the additional waiting period before surgery, making the treatment suitable for patients with malignant disease. 4 2020 45

meetings | 4 Fig. 4: Dentsply Sirona’s new Schick AE intra-oral sensor. event lends support to the idea of the strength of online clin- ical education. Dr. Michael Watson, who practices dentistry in Wake Forest, North Carolina, said that the virtual format of DS World 2020 had proved useful to many dentists. He stated in press material that “this format of clinical edu- cation will continue to be a great option for dental profession- als, especially those who want to experience this level of presentation without having to travel or close their offices.” “This is one of the great things that we have learned in 2020: how you can do virtual events and really interact with people,” Casey said. Dentsply Sirona has announced that next year’s DS World will return to the desert metropolis of Las Vegas—where it has been held previously—as an in-person event. Casey told attendees that the event will be held at Caesars Forum in Las Vegas from 23 to 25 September 2021. in their discipline, but often do not receive training in what leadership requires in the dental practice. “Leadership is a skill,” he said. “We have to study it, learn it, and practice it like any other skill.” Sinek’s advice to dental professionals who are running a small business and trying to survive the tough pandemic business environment was to do all that they can to continue learning about leadership. “Study it, read an article, watch a TED Talk,” he said, adding that the best leaders have one thing in common: they get together and they talk about it. During the opening session, Puri and Casey also encour- aged attendees to take full advantage of the CE opportu- nities that were on offer in close to all dental disciplines at DS World 2020. They pointed out that a virtual format did not mean reduced personal contact and networking oppor- tunities. Casey urged attendees to interact with key opinion leaders and other attendees during breakout sessions and panel events. The live surgeries focused on topics such as the digital workflow for implant therapy in the aesthetic zone, and whereas the surgical procedures were available on de- mand, participants were invited to take part in synchronous post-procedure discussions. New products for a new era in dental care “Let’s deliver on innovation,” Casey told the dental press in an online briefing, remarking that it was through innova- tion that the company planned to change the global face of dentistry and dental education. Attendees had the chance to learn about the intra-oral scanner Primescan and the SureSmile Aligner during online lectures, and break- out sessions presented the opportunity for attendees to experience advancements in procedural workflow and digi- tal dentistry, such as the new Axeos 2D/3D imaging system and the Schick AE intra-oral sensor. Dentsply Sirona says that Axeos—which won the Red Dot Award for product design this year—is its extra-oral radiography unit with the larg- est field of view and delivers optimal image quality at low- dose optimised exposure. “Axeos has exactly the right bal- ance between excellence, speed and precision,” Prof Chung How Kau, chairman and professor of orthodontics at the Department of Orthodontics at the University of Alabama at Birmingham, was quoted in press material as saying. The Schick AE sensor is a reliable diagnostics tool owing to its low dose exposure, optimised resolution and improved display of the anatomical structures, company informa- tion states. The sensor combines a theoretical resolution of 33 lp/mm with newly optimised data readout and filtering functions in order to enhance diagnostic capabilities. Be- fore the event, Dr Leonard Patella, who specialises in im- plant and cosmetic dentistry in Garden City, New York, told Dentsply Sirona: “I get a solid basis for a safe and accurate diagnosis of my patients, even in lower X-ray dose ranges.” The virtual format of this year’s DS World was necessary due to health and travel restrictions, but the success of the Fig. 5: The Axeos 2D/3D imaging system has the largest field of view among Dentsply Sirona’s extra-oral radiography units. 5 4 2020 47

DEDICAM PRODUCTS IMPRESS. With an efficient digital workflow and Camlog quality. EVERYTHING FROM A SINGLE SOURCE. Tailored to your individual needs. Open interfaces, precise fabrication and punctual delivery EVERYTHING IS COMPREHENSIVE Wide range of implant manufacturers supported. . K U e h t d n a d n a l r e z t i w S , s d n a l r e h t e N , y l a t I , d n a l e r I , y n a m r e G , e c n a r F , k r a m n e D , a i r t s u A : n i e l b a l i a v a e r a s e c i v r e s M A C I D E D

TRULY CONICAL PRECISION TRULY CONICAL PRECISION CONELOG® CONELOG® PROGRESSIVE-LINE PROGRESSIVE-LINE conical performance 1, 21, 2 conical performance 1, 2 at bone level at bone level Precise conical connection long conus for reduced micromovements superior positional stability in comparison to other conical systems 1,2 easy positioning with excellent tactile feedback integrated platform switching supporting the preservation of crestal bone [1] Semper-Hogg, W, Kraft, S, Stiller, S et al. Analytical and experimental position s [1] Semper-Hogg, W, Kraft, S, Stiller, S et al. Analytical and experimental position stability of the abutment in different dental implant systems with a conical implant–abu of the abutment in different dental implant systems with a conical implant–abutment connection Clin Oral Invest (2013) 17: 1017 [2] Semper Hogg W, Zulauf K, Mehrhof J, Nelson K. The influence of torque tightening on the position stability of the abutment in conical implant-abutmen tightening on the position stability of the abutment in conical implant-abutment connections. Int J Prosthodont 2015;28:538-41 www.biohorizonscamlog.com 0 2 0 2 1 1 - 1 0 - L C H B - T N I - N E - V D A - 1 1 1 0 - M