issn 2193-4673 • Vol. 17 • Issue 2/2021 roots international magazine of endodontics 2/21 technique Lane keeping assistance systems in endodontics trends & applications Principle-driven endodontics: Proven case results case report Er:YAG laser for superior endodontic treatment

editorial | Magda Wojtkiewicz Managing Editor While taking care of others, you should remember to take care of yourself Self-care is one of those things that is essential, but we often do not take enough time for it, or feel that we do not have enough time or knowledge. However, taking care of yourself—your body, health and mental well- being—is most important not only in order to feel better but also in order to perform better in the long run and to be able to help others better. Back pain is one of the most common problems among dental professionals. The results of a study conducted in 2015 showed a 70.0% incidence of back pain among dentists, lower back pain predominating in 47.6% of cases.1 Such findings demonstrate a high prevalence of lower back pain among dental professionals. Unfortunately, the importance of ergonomic working posture is usually not the focus of dental students and young practitioners. Dr Ali Nankali in his article “Back pain—a clinician’s nightmare” (page 42) empha- sises that many young clinicians are aware of their incorrect posture and positioning, yet they do not know how to correct it: “The lack of confidence does not allow them to challenge their habits on their own, and so they often seek help” and “Many dentists who do not know how to manage back pain try to work in a stand- ing or a different sitting position, which, unfortunately, is reported to lead to more intense pain, especially in the upper and lower back areas”. Another study, conducted by Swedish researchers between 2012 and 2014, concluded that “understand- ing the relationship between working conditions and well-being is crucial to being able to design specific interventions for oral healthcare providers which will improve their working conditions and health”.2 The lead author of the study, Dr Charlotte Wåhlin from Linköping University, recommends that dental professionals use ergonomic exercises in the daily practice to prevent work-related disorders. Undeniably, offering high-quality treatment to patients should be the focus of every dental professional, but it should never come at the expense of their health or well-being. Therefore, striking a balance between self- care, including correct working posture, atmosphere at work, and physical and mental health, and professional performance is crucial for obtaining the best results in the long term. Magda Wojtkiewicz Managing Editor References 1. Gaowgzeh RA, Chevidikunnan MF, Al Saif A, El-Gendy S, Karrouf G, Al Senany S. Prevalence of and risk factors for low back pain among dentists. J Phys Ther Sci. 2015 Sep;27(9):2803–6. doi: 10.1589/jpts.27.2803. 2. Wåhlin C, Lindmark U, Wagman P, Johnston V, Rolander B. Work and health characteristics of oral health providers who stay healthy at work— a prospective study in public dentistry. Eur J Physiother. 2021 Apr 6. doi: 10.1080/21679169.2021.1905876. roots 2 2021 03

CanalProTM Jeni Digital assistance system for canal preparation Jeni – ready – go! NEW The revolutionary CanalPro Jeni in a nutshell! Watch now! https://youtu.be/Qw3uc3hSTkg Autonomous «navigation» in the endo canal owing to revolutionary software › Digital assistance system for canal preparation controls the file movement at millisecond intervals › Movement profile of the file continuously adapts to the individual root canal anatomy › Irrigation recommendation is indicated by an acoustic signal › Due to the integrated apex locator and fully insulated angled handpiece, continuous measurement of the working length is possible in real time info.de@coltene.com | jeni.coltene.com . 1 2 4 0 6 9 6 6 0 0

us to have the necessary and appropriate discussion before and throughout the treatment procedure. Currently, you are the Slow Dentistry honorary global ambassador for Hungary. How did that come about, and what do you aim to accomplish through this role? If you consider where Hungary started half a century ago, you would understand the great importance of this role. Also, dental tourism is very popular in our country. Patients arrive from another country for full-mouth dental treatment and typically remain for seven to ten days. I am very sceptical about the quality of the long-term success of those treatments. I would like to introduce a collaboration between Slow Dentistry and the Hungarian Dental Association through which we could grant the Slow Dentistry badge to those dental offices which are working strictly according to Slow Dentistry’s principles. It could be a great help for both Hungarian and foreign patients in choosing their dentist in order to receive quality treatment in the safest environment. Dr Miguel Stanley, who founded Slow Dentistry and wrote in Part 1 of this series that “The general pub- lic currently has no idea of their rights at a dental appointment.” What is your take on this? Throughout my career, I have been able to work in differ- ent countries. Dental education has always been famed in our country, and there is a high percentage of practi- cal learning opportunities for our students. After gradua- tion, practitioners tend to forget what they learned about quality and safety and how to apply this. Slow Dentistry summarises and structures those most important rules “Communication needs not only skills but also time for patients and professionals.” that we have learned over the years and which every single dental professional can follow. I am also hoping that, after easing of COVID-19 lockdown restrictions, we as Hungarian dental professionals can invite Dr Stanley to a meeting to convey these extremely important messages of Slow Dentistry to our audi- ence, because I believe that a personal discussion with Dr Stanley, who has amazing communication talents, always gives a unique and irreplaceable boost. Editorial note: Visit www.slowdentistry.com for more details. about Prof. Katalin Nagy has received university training and specialty qual- ifications in oral surgery, prosthodon- tics and implantology. Her main field of research is oral cancer. Prof. Nagy is currently adviser to the Hungarian health minister on dental issues, being president of the Hungarian Dental Association, and she is head of the Department of Oral Surgery at the University of Szeged, as well as the owner of two private dental offices in Szeged and Budapest in Hungary. roots 2 2021 07

study | the limitation of providing a 2D image of a 3D com- plex structure. The use of radiographs alone in work- ing length determination led to over-instrumentation in 33% of molars and 56% of premolars.10 The intro- duction of electronic apex locators (EALs) into clini- cal practice allowed, when used with appropriate radiographs, the determination of a more predictable and accurate working length,11, 12 and a substantially lower number of radiographs are necessary when us- ing EALs, consequently reducing patient exposure to X-ray radiation.13 Vieyra et al. showed that Root ZX lo- cated minor foramina 68% of the time in premolar and anterior teeth compared with radiographs, which did so 20% and 11% of the time in anterior and premolar teeth, respectively.14 In the last decades, different generations of EALs have been developed. Several studies have been conducted on different EALs to evaluate their accuracy under different conditions.15–18 The DentaPort ZX (J. Morita) is a third-generation EAL based on dual frequencies (8 and 0.4 kHz), and it is considered the gold standard EAL to which any new device should be compared. Several ex vivo19 and in vivo20 studies have clearly demonstrated its precision. Among these studies, as an example, Connert et al. showed that, in a com- parison of nine apex locators using micro-CT, the DentaPort ZX was the most accurate at detecting api- cal constrictions and major foramina, having an accu- racy of 99% and 100%, within a tolerance of ± 0.5 mm or ± 1.0 mm, respectively.15 AirPex (Eighteeth, Changzhou Sifary Medical Technol- ogy) is a new wireless apex locator that is charged on a charging base. It weighs 15 g, and its dimensions are 4.8 × 2.8 × 1.6 cm. In the literature, no data is yet avail- able on this EAL. Thus, the aim of the present ex vivo study was to compare the accuracy of the AirPex and the DentaPort ZX EALs in determining working length in extracted teeth. Material and methods In this study, 15 single-rooted teeth, extracted for peri- odontal or orthodontic reasons, were selected. The teeth were placed in a 5.25% sodium hypochlorite (NaOCl) solution for 2 hours in order to remove organic residue. The remaining tissue was removed from the external root surfaces using a periodontal scaling instrument. Finally, the teeth were stored in normal saline (0.9% sodium chloride) before testing. To rule out previously treated root canals, open apices, resorbed roots, teeth with two canals or teeth filled with amalgam or composite, two digital radiographs in both buccolingual and mesiodistal projections were obtained. After standard access cavity preparation, the 1 Fig. 1: Determination of the actual working length under a stereomicroscope at 20× magnification. As a particular detail, a grey spot shows the file on top of the major apical foramen. patency of the apical foramen was assessed with size 10 and 15 K-files (Dentsply Maillefer). Samples in which a size 20 K-file reached the apex were ruled out and substituted. The actual working length (AWL) was determined by introducing a size 10 K-file into the canal until its tip emerged in the apical foramen under 20× magnifica- tion using a stereomicroscope (Zeiss Axiophot, Carl Zeiss) linked to a digital camera (Moticam Pro SMP, Motic; Fig. 1). With the aim of reducing the risk of stop- per movement, two silicone stoppers were positioned on the file. After the removal of the file, the distance between the stoppers and the file tip was measured to establish the AWL. The roots of each tooth were immersed in a plastic box filled with alginate, leaving the most coronal 5 mm uncov- ered. Alginate was useful for obtaining an environment as analogous as possible to the oral one. The wire of the EAL was connected to the file inserted into the root canal, while the lip clip was immersed in the alginate. AirPex (Fig. 2) and the DentaPort ZX (Fig. 3) were used according to the manufacturer’s instructions. When the AirPex was used, a size 10 K-file was inserted gently until 2 3 Fig. 2: The AirPex apex locator. Fig. 3: The DentaPort ZX apex locator. roots 2 2021 09

study | m o c . k c o t s r e t t u h S / p e e d a V © l The presence of irrigants inside root canals does not affect the accuracy of the majority of the latest genera- tions of EALs.26 Duran-Sindreu et al. compared in vivo the accuracy of Root ZX and iPex in determining work- ing length in the presence of two different irrigant solu- tions.27 They reported statistically significant differences between the two apex locators, but their accuracy was not affected by 2.5% NaOCl or 2.0% chlorhexidine.27 Çınar and Üstün compared in vivo the accuracy of Propex Pixi, Root ZX mini and RAYPEX 5 using micro-CT.29 They found no differences in determining working length measured in the presence of blood, pulp tissue or NaOCl.28 Tsesis et al., in a systematic review and meta-analysis, concluded that the presence of vital or necrotic pulp has no effect on the precision of EALs.29 In the present ex vivo study, conducted under normal conditions, the EWL measurements were very accurate for both AirPex and the DentaPort ZX. The results of the present study are in agreement with previous in vivo and in vitro investigations. Saatchi et al., in an in vivo study, reported that the DentaPort ZX showed an accuracy to within ± 0.5 mm of 93.8% in the presence of periapical periodontitis and of 93.3% in teeth with normal periapices.30 Piasecki et al. showed in vivo that Root ZX II located the apical foramen accu- rately to within ± 0.5 mm in 83% of the teeth with periapi- cal periodontitis and in 100% of the vital teeth.31 Stöber et al., under in vivo clinical conditions, measured a mean distance of 0.146 ± 0.430 mm from the AWL to the file tip and an accuracy to within ± 0.5 mm of 72% and to within ± 1.0 mm of 100%.32 Silveira et al. reported an accuracy of Root ZX of 91.7% in detecting apical constrictions in vivo.33 Comparing working length determination in vivo and in vitro, Duran-Sindreu et al. reported that Root ZX was accurate to ± 0.5 mm 74% of the time in vitro and to ± 0.5 mm 78.3% of the time in vivo.34 Soares et al. evaluated Root ZX II in detecting major foramina and found an accuracy to 0.5 mm in vivo and in vitro of 70% and 70% of the time, respectively.35 The differences in the results shown in these studies for the accuracy of DentaPort XZ could be explained by the different methods used to establish the AWL. This is the first ex vivo study involving AirPex. No previ- ous scientific literature has been published on this EAL. The data showed comparable results with the DentaPort ZX (P > 0.05). Conclusion In conclusion, AirPex and the DentaPort ZX were accu- rate in detecting working length, showed no statistically significant differences in accuracy and showed accuracy to within ± 0.5 mm. Confl icts of interest The authors declare that there are no conflicts of interest. Acknowledgements The authors thank Eighteeth (Changzhou Sifary Medical Technology) for donating the AirPex apex locators for this study. Editorial note: A list of references is available from the publisher. about Drs Rosalba Diana, Raffaella Castagnola, Mauro Colangeli, Luca Marigo and Nicola Maria Grande work in the department of conservative dentistry and endodontics at the Agostino Gemelli IRCCS University Hospital Foundation in Rome in Italy and at the Institute of Dentistry and Maxillofacial Surgery at the Università Cattolica del Sacro Cuore in Rome. Claudia Panzetta works in the department of neuroscience at the Università Cattolica del Sacro Cuore in Rome in Italy. Dr Filippo Cardinali is in private practice in Ancona in Italy. Dr Gianluca Plotino is in private practice in Rome in Italy. roots 2 2021 11

2 3 4 5 6 Fig. 2: Pre-op radiographic image of tooth #37 (Case 1). (Image: © Dr Thomas Rieger) Fig. 3: Post-op radiographic. (Image: © Dr Thomas Rieger) Fig. 4: Pre-op radiographic image of tooth #36 (Case 2). (Image: © Dr Silviu Bondari) Figs. 5 & 6: Post-op radiographic images. (Image: © Dr Silviu Bondari) on Jeni’s touch screen. The HyFlex CM or EDM and the MicroMega One Curve or 2Shape from COLTENE are already pre-installed in the software. In the latest update, the 30/.07 HyFlex and MicroMega Remover files were added, making a significant difference to an endodontic revision treatment. The new Remover files fit perfectly with the established file systems and quickly and reliably remove inadequate gutta- percha fillings as well as similar endodontic restorations that have become outdated. In the Doctor’s Choice program, users can also store up to eight additional filing systems of their choice if they are familiar with the respective motion protocol. In Case 1, the appropriate access was achieved with an orifice opener. The extreme curvature in the apical third presented a particular challenge during preparation. The following sequence was therefore used: the 10/.05 HyFlex EDM file was followed by the 20/.05, and the universal file 25/~ HyFlex EDM OneFile then performed most of the work in the mesial and distal root canals. The final sequence involved the 40/.05, 50/.03 and 60/.02 files in the distal root canals for final shaping. In this process, Jeni enabled rapid preparation despite the highly curved profile of the root canals. Each file virtually worked itself to its working length. The natural shaping of the root canals is clearly shown in the postoperative radiographic image (Fig. 3). Frequent rinsing with efficient material removal A revision treatment by Dr Silviu Bondari from Beuzeville in France also demonstrates that retreatment can be per- formed quickly and easily with the new endodontic motor. In a 30-year-old patient, removal of the insufficient gutta -percha filling also proved necessary owing to periapical periodontitis in tooth #36 (Fig. 4). At a speed of 1,000 rpm with continuous rotation, a delicate MicroMega Remover file was inserted to over two-thirds of the distal root canal length. The remainder of the root was then treated with a HyFlex EDM OneFile in the contra-angle handpiece at 500 rpm. HyFlex EDM files of size 20/.05 were used in the mesial root canals. The speed was also set at 500 rpm. The HyFlex EDM OneFile was then used in the mesial canals for final shaping of the root canal. A 40/.04 EDM file was used in the distal root canal. The result on the radiograph promised a more durable obturation than the initial treatment five years earlier (Figs. 5 & 6). Thorough rinsing is recommended in endodontics, espe- cially for the efficient removal of material, be it dentine or old filling material from a revision treatment. If too much material remains in the root canal, the file may block and, in the worst case, even break. At the working speeds of modern NiTi files, even endodontic experts often under- estimate how much debris has already accumulated in the root canal. Here too, an acoustic signal helps, automatically sounding when rinsing would prove advisable. Seamless integration For dentists who prefer using cordless motors because of their reduced weight, Jeni ticks all the boxes. It can be conve- niently placed chairside on a small rolling table and, thanks to its long battery life, no cumbersome power cable is required, so the instrument of the future can be easily integrated into one’s practice. Interested dentists will probably be able to conduct the first trials with the new endodontic motor no later than at the 2021 International Dental Show in the autumn. Conclusion Digital endodontic assistance systems speed up prepa- ration by controlling the rotary motion fully automatically, making preparation considerably safer and more reliable. This is especially true in the case of irregular root canal anatomies, where the co-pilot will in future help to shape root canals naturally while being a reliable reminder of the appropriate rinsing protocol. about Dr Barbara Müller studied agricultural biology at the University of Hohenheim in Stuttgart in Germany and obtained an MSc from the University of Georgia in the US. In 1993, she completed her PhD at Ulm University in Germany. Between 1996 and 2010, Dr Müller held the position of research and development manager at COLTENE, and she has been involved in the development of products such as RoekoSeal, GuttaFlow and HyFlex CM nickel–titanium files. Since 2011, she has been head of the company’s endodontic product segment. She has been a guest speaker at numerous events hosted by European dental and endodontic societies. roots 2 2021 13

trends & applications | 5a 5b 6a 6b Figs. 5a & b: Case treated with Chlor-XTRA and SmearOFF with EndoUltra activation. Note the excellent cone fit and apical control of obturation. (Images: © Dr Sam Alborz) Figs. 6a & b: Case treated with Bassi Logic controlled memory NiTi files. Note the visualisation of the third root on this mandibular molar and conservative canal preparation shape. (Images: © Dr Alex Chan) erence of endodontists globally to use warm obtura- tion techniques and activated irrigation (concepts dis- cussed in greater detail later in this article). Specialist preferences also are hedged by the eyeball test, the visual evidence that is observed in treatment in com- parison with prior techniques. Hence, this article will focus on key technique objectives that universally are agreed upon. As a starting place, before ever picking up a syringe, the two single greatest prerequisites for creating excellent endodontic results are time and compre - hensive treatment planning. It is essential that the clinician have enough time to carry out the treatment in a relaxed but productive environment, in essence, practising with high efficiency. It is axiomatic that the clinician only starts cases that he or she believes he or she can finish well and never treats a patient solely for money. All procedures must be carefully pre-planned. Such treatment planning includes performing high-level im- aging and a thorough clinical examination to determine a definitive diagnosis. Preoperative treatment planning includes informed consent, assurance of restorability, profound pain control (local anaesthesia), visualisation and magnification (surgical microscope), instrumenta- tion (stainless-steel and nickel–titanium [NiTi]), irrigation and disinfection protocols, obturation and coronal seal strategies prior to endodontic access. A lack of treat- ment planning strategies is the harbinger of endodontic misadventure (Figs. 1–3). 7a 7b 7c 7d 7e 7f 7g Figs. 7a–g: Cased treated with PIPs (photon-induced photoacoustic streaming). Note the orifice barrier placed in composite to protect the endodontic treatment from coronal leakage. (Images: © Dr Paula Elmi) roots 2 2021 15

trends & applications | 9a 9d 9b 9c Figs. 9a–f: Case assisted with CBCT to determine the anatomy preoperatively. Note the multiple cross sections moving apically and the correlation to the 2D view. Note also the conservative taper in relation to the root width. (Images: © Dr Brett Gilbert) 9e 9f Endo). This notwithstanding, the goals of canal shaping are identical regardless of the system used. Regardless of the instrumentation system used, patency is always sought during canal scouting and instrumentation. Cli- nicians can debate the relative merits of reciprocation versus rotary motion, optimal austenite finish tempera- tures (austenite transformation temperatures that con- trol whether a file undergoes martensitic transformation), controlled memory files ground by computer numerical control machines versus twisting NiTi in R phase, along with a multitude of different similar clinical issues. Re- gardless of these nuances, it is the adherence to basic principles of canal preparation that files create a pathway from the coronal to the apical aspect to allow irrigant to flow into all of the canal ramifications, cleaning the root canal system and optimising clinical success. Goals of canal preparation include keeping the canal centred in its original position within the root structure and keeping the apical foramen at its original position and size. One of the hallmarks of all the cases illustrated is that the apical foramen has been respected. Specifi- cally, it has not been moved, transported, zipped or al- tered in any way. Reaching the apical constriction with- out transporting the canal and eliminating all debris from the canal and providing a tapering funnel from orifice to apex is a key canal preparation objective. The final prepared canal shape should be large enough to irrigate and obturate, but not so large as to structurally weaken the tooth. For practical purposes, while treat- ment philosophies differ, the minimum final prepared taper should be .04 and the minimum final prepared apical diameter size 30 (depending on the initial size of the foramen). Given the advent of controlled memory NiTi, there is little indication for larger tapers, especially in fine 3D apical curvatures. As mentioned, patency is essential because its obtain- ment means that the clinician can always reach the apex during every phase of treatment, and its loss means that tissue, toxins and bacteria can remain despite irrigation procedures, especially in the apical third. Apical debris is the harbinger of iatrogenic events, including canal transportation, zipping, irrigant extrusion and a lack of optimal canal cleaning. Conceptually, root canal system cleansing can be divided into a macro-phase and a micro-phase. Debridement with files is the macro-cleaning. Removal of bacteria and biofilm from the canal walls and dentinal tubules with an- timicrobial solutions is the micro-cleaning. During preparation, it is axiomatic that debris should be removed as quickly as it is produced regardless of whether it is in the chamber or canals. Inserting a NiTi file into a dry canal full of debris in an effort to make apical progress is the harbinger of blocked canals and sepa- rated files. This action packs the fine 3D anatomy (apical deltas, fins, cul-de-sacs, isthmuses, etc.) of canals with debris that can become much more difficult to remove later in the treatment process. Alternatively, irrigating after the insertion of every file and recapitulation with hand files is ideal to prevent the subsequent build-up of debris, improve circulation of irrigant apically and optimise irrigant refreshment. Today’s rotary files are designed to funnel debris out of the canal in a coronal direction, further facilitating the debris removal. roots 2 2021 17

trends & applications | 11 12a 12b Fig. 11: Note the degree of penetration of sealer and gutta-percha between the primary canals. Obturation of this space demonstrates both the macro- and micro-cleaning referred to in the article. (Image: © Dr Nestor Cohenca) Figs. 12a & b: Note the attention to detail required to locate all of the canals in this exceptional case done under the surgical microscope. (Images: © Dr Adrian Silberman) (EndoVac) and the other utilises ultrasonic energy (EndoUltra). Regardless of which method is utilised to deliver irrigant to the apical third, it is most critical that the clinician activates the irrigant and does not rely simply on cold passive syringe irrigation. While protocols vary, activating each primary irrigant (both SmearOFF and Chlor-XTRA, for example) three times in each canal for 20 seconds is a sound clinical strategy (Figs. 10–12). GentleWave deserves a special mention, as it is un- like the other activation systems available. GentleWave delivers a multisonically activated degassed solution (to remove air bubbles that dissipate energy) with negative to neutral pressure delivered via a handpiece over the access in a closed system. The literature basis sup- porting the system shows impressive cleansing of the root canal systems, but a definitive high-level study on improved healing has not been published to date. The system costs approximately $80,000 per console and $50–$100 per one-time use handpiece. Its future application and expansion globally will be interesting to observe. And finally, the literature is conclusive that placing a post-endodontic coronal seal at the time treatment is completed, under a dental dam, is closely associ- ated with endodontic success. Please note that all of the cases illustrated had some form of orifice barrier or build-up placed under the dental dam at the time of treatment. This article has stressed literature-based proven treat- ment principles over a particular manufacturer’s devices or technique recommendations. Emphasis has been placed on an accurate diagnosis, conservative access, patency, minimal taper, activating irrigation, 3D warm obturation and the placement of a post endodontic cor- onal seal at the time of treatment under the dental dam. We welcome your feedback. Editorial note: A list of references is available from the publisher. This article was first published in the US in issue 1/19 of roots—the international magazine of endodontics. about Dr Brett E. Gilbert graduated with a DDS from the University of Maryland School of Dentistry in Baltimore in the US in 2001 and completed his postgraduate training in endodontics at the same dental school in 2003. He is currently a clinical assistant professor in the Department of Endodontics at the University of Illinois at Chicago College of Dentistry and on staff at AMITA Health Resurrection Medical Center Chicago, both in the US. He is a past president of the Illinois Association of Endodontists. Dr Gilbert is a diplomate of the American Board of Endodontics. He was named a top ten young dental educator in America by the Seattle Study Club in 2017. In 2019, he was named to Academic Keys’ Who’s Who in Dentistry Academia. Dr Gilbert lectures nationally and internationally on clinical endodontics. He has a full-time private practice limited to endodontics in Niles in Illinois in the US. He can be contacted via his website, www.drbrettgilbert.com. Dr Richard Mounce, DDS, lives on the Oregon coast and practises part time in Eagle River in Alaska, both in the US. He has lectured globally in more than 30 countries, is widely published in dental trade magazines and has consulted for a large number of endodontic companies. His favourite current pastime is beachcombing with his dog, Zinho. He can be reached at richardmounce@mounceendo.com. roots 2 2021 19

case report | for rapid fluid movement during expansion and con- traction of the bubbles. A modified method, known as SWEEPS (shock wave enhanced emission photo- acoustic streaming),5, 6 has been developed as an up- grade of the SSP technique and is particularly suitable for very confined spaces. Unlike the SSP technique, the SWEEPS technique delivers pulses in pairs. The second pulse exerts pressure on the ini- tial bubble, which is generated by the first pulse, and accel- erates its collapse and the emergence of a new generation of bubbles. In this way, even in very narrow geometries, shock waves are formed that travel faster than sound (acoustic waves). The optimal time difference between pulses in a pair depends on the volume and anatomy of the confined space. When the correlation between tooth anatomy and the time between pulses in a pair cannot be defined ex- actly, a special modality of the method, known as AutoSWEEPS, is used, whereby the time separation between laser pulses in a pair varies continuously be- tween 250 and 650 microseconds, in increments of 10 microseconds. This ensures that during each cleaning cycle there is always an optimal time distance between the pulses, which is necessary for the emission of shock waves and thus for the maximum possible flow efficiency according to the dimensions of the irrigation system.5, 6 The efficiency of either SSP or SWEEPS in removing bio- film and debris can be enhanced with chemical irrigants. In endodontics, the two most commonly used irrigants are sodium hypochlorite and EDTA. Endodontically treated teeth are often more prone to crown or root fracture compared with vital teeth. Several factors contribute to this, the most important being that non-vital teeth often have less sound tooth structure owing to progressive carious lesions, trauma or previous restorations. Certain clinical procedures may also lead to a higher incidence of tooth fracture in endodontically treated teeth, such as creation of large access cavities, excessive mechanical shaping of the roots, prolonged use of different irrigating solutions (sodium hypochlorite, EDTA) and medications (calcium hydroxide) during endodontic treatment, improper restorative treatment without cuspal coverage in the posterior region, and high masticatory forces in cer- tain individuals. Once the tooth has broken off below the gingival margin, it is often very difficult to restore it properly, and additional clinical procedures such sur- gical lengthening of the clinical crown or orthodontic extrusion are needed. When placing a new restoration, the biologic width of the tooth has to be respected and the margin of the restoration should be at least 2.15–2.30 mm (preferably around 3.0 mm) from the crestal bone, to allow for a normal epithelial junction and connective tissue attachment to avoid chronic inflammation and periodontal tissue loss. 5 7 6 8 Figs. 5 & 6: Tooth #36 with broken lingual wall 14 days after crown lengthening. Figs. 7 & 8: Tooth #36 with composite build-up before endodontic treatment. Case presentation A 28-year-old male patient was referred to our clinic for endodontic treatment of a mandibular molar owing to chronic periapical periodontitis. He stated that a few weeks before the appointment, a large part of the tooth had broken off. The patient was healthy, took no medi- cation and reported no allergies. There was no trauma to the dentition in the patient’s dental history. Intra-oral examination revealed moderate plaque control and oral hygiene. All third molars had been removed in the past, and teeth #16, 24, 26 and 36 had already been endodonti- cally treated. The gingiva was quite healthy, pink in colour, and did not bleed on probing. Probing depth was normal around all teeth. There were no pathological conditions on the tongue, mucosa, or hard or soft palate, or in the oropharynx. The occlusion was Angle Class I. The intra-oral clinical ex- amination showed that tooth #36 had a large mesioocclu- sal-distal (MOD) composite filling and that the buccal wall was intact, whereas the lingual wall of the tooth crown had broken off about 2 mm below the gingival margin. The tooth was slightly tender to percussion and sensitive to palpation adjacent to the apex of the tooth. The mobility of the tooth had not increased. Probing depth was normal, but there was slight bleeding on probing on the lingual side (Figs. 1 & 2). Analysis of a radiograph showed the large MOD filling and the broken lingual wall of the tooth (Fig. 3). The tooth had been endodontically treated in the past; the root fillings were porous and short in the mesial root. There were bone lesions (chronic periapical periodontitis) under both the mesial and distal roots. Diagnosis The diagnosis was chronic periapical periodontitis and a broken lingual wall of the tooth crown. roots 2 2021 21

case report | 9 10 Fig. 9: Radiograph of tooth #36 three months after the clinical crown lengthening and endodontic treatment. Fig. 10: Panoramic radiograph three months after the treatment. A dental dam was placed on the tooth and the working field isolated. An endodontic access cavity was prepared and the root canals were negotiated to the apex with a size 8 hand C-file. Sequentially larger rotary files (HyFlex CM and EDM, COLTENE) were used to working length up to size 30 for the mesial canals and size 40 for the distal canal. Between each filing, the AutoSWEEPS irrigation protocol was used with 2.5% sodium hypochlorite for 30 seconds, followed by a 30-second rest phase, and no water or air. The access cavity was filled with irrigant constantly during the procedure. After the final shaping of the canals, the final irrigation protocol was performed. This consisted of a single 30-second irrigation cycle with EDTA, followed by a single cycle with distilled water and three 30-second cycles with 2.5% sodium hypochlorite, using the laser parameters stated in Table 5. After drying, a calcium hydroxide dress- ing was placed in the canals and the endodontic access cavity was temporarily sealed. At the third clinical appointment, the calcium hydroxide was rinsed out of the canals. For the irrigation, a single 30-second EDTA cycle, followed by a single 30-second distilled water cycle and three cycles of 30-second AutoSWEEPS irrigation with 2.5% sodium hypochlorite were repeated, using the same energy setting as at the first clinical appointment. The canals were dried and filled with gutta-percha cones and a bioceramic sealer (Biodentine, Septodont) using the cold lateral compaction technique. A stronger temporary filling made of composite material was placed at the end of the procedure. The patient was referred back to his general practitioner with instructions for a final restoration of the tooth with an endocrown after six months, once the periodontal tissue and the periapical lesions had healed completely. In the first week of healing, the patient rated his pain one on a scale of one to ten. Fourteen days after the crown lengthening procedure, the gingival margin looked healthy and had reattached at the new level with no observable bleeding on slight probing. It was possible to perform the composite build-up as an endodontic pretreatment with minimal effort. The endodontic treatment was finished without any complications, and the three-month radio- graphic follow-up showed excellent healing of the periapi- cal lesions (Figs. 9 & 10). For the final restoration, the level of the gingival margin might have had to have been slightly adjusted further using the same procedure. Conclusion Our clinical case shows that the Er:YAG laser can be used with great ease and predictability when crown lengthening is indicated. This procedure can be performed as a pre- treatment of the tooth for endodontic treatment or before placing the final restoration. It is easy to perform, but just as important—or even more so—is that it causes minimal to no pain and discomfort for the patient and promotes excellent healing of the periodontal tissue. Moreover, this case demonstrates the successful use of the SWEEPS mode to increase the fluid dynamics of the irrigant and thereby to improve the cleaning efficacy of the root canals in the treatment of chronic periapical peri- odontitis. As the sodium hypochlorite reaches even the most apical parts of the root canal system and provides sufficient disinfection, it is not necessary to prepare the canals to larger apical sizes or tapers, which is the case when only conventional irrigation methods are used. This technique truly represents a paradigm shift in the way that endodontic treatment is performed. about Dr Igor Križnar graduated with a DMD in 2006 from the University of Ljubljana in Slovenia and began working as an assistant in the department of endodontics and operative dentistry in the Faculty of Medicine. He acquired the professional title of dental specialist in endodontics in 2014. Until the end of 2015, he worked as an assistant at the faculty, where he was engaged in work with dental students in clinical and preclinical practice. At the same time, he worked as a dental specialist at the University Medical Centre in Ljubljana. He was also engaged in research work and earned his PhD in endodontics from the University of Ljubljana in 2016. In December 2015, he entered into full-time private clinical practice focusing mainly on endodontics. In 2019, he completed the Laser and Health Academy master in laser dentistry. Dr Križnar has published numerous scientific papers in various journals and has actively participated in many international and local conferences and symposia. roots 2 2021 23

case report | 4 5 6 Fig. 4: Pre-op radiograph. Fig. 5: Immediate post-op radiograph. Fig. 6: Four-month post-op radiograph. of tooth #26 and periapical disease in teeth #26 and 27 (Figs. 2 & 3). After careful analysis of all clinical and imaging data, the diagnosis was chronic periapical periodontitis of teeth #26 and 27 probably because of unsatisfactory root canal ther- apy. As an emergency procedure, the abscess was drained. Two alternatives were considered to solve the case. The first would have involved removal of the crowns and posts with the purpose of providing access for standard re- treatment. Consequently, after root canal intervention, the posts and crowns would have had to have been re- built. The second was a microsurgical approach aimed at root canal retro-filling of both teeth. One major benefit of the latter would have been that the posts and crowns would not have had to have been removed. After detailed explanation of all advantages and compromises of the two options, endodontic microsurgery was selected. For personal reasons, the patient did not return until 8 April 2018 (Fig. 4), and surgery was scheduled for 4 June 2018. Preoperative medication was 4 mg of oral dexamethasone for pre-emptive analgesics,13 1 hour before the procedure. Local anaesthesia was administered with 3.6 ml of 4% artic- aine and 1:100,000 adrenaline: palatal infiltration of 0.9 ml and 2.7 ml at the site between the attached gingiva and buccal oral mucosa. After anaesthesia, two intrasulcular incisions were followed by a vertical releasing incision. Piezo-syndes- motomy was performed with an ultrasonic tip (PR1, mectron). Because of the infection, the buccal cortical bone had already ruptured, which facilitated finding the apex of the distobuccal root of tooth #26. However, osteotomy was required to reach the apices of the buccal roots of tooth #27 and mesiobuccal root of tooth #26. Piezo-osteotomy was performed with the ultrasonic tips OT12 and OP7 (mectron) and exposed the entire lesion. For the api- cectomies, the ultrasonic piezoelectric system was also used (OT12 tip). All apices were cut perpendicular to the long axis of the roots to completely remove any possi- ble ramifications and branching of the root canal system. With ultrasonic tips P1 and P1T (Helse Ultrasonic), the retro- preparation was performed. The root canals were retro-filled with Bio-C Repair (Angelus). Material insertion at the retro- cavity was facilitated by product consistency and its ready- to-use, premixed presentation. There was no need for specific instruments or applicators to fill the retro-cavity. With this step done, to avoid connective tissue growth into the osseous defect, the apical bone cavity was filled with surgical calcium sulphate (New Osteo, GMReis; Fig. 5). Postoperative images were obtained at baseline and at four months, when it was possible to observe complete bone repair (Figs. 6–12). Discussion The operating microscope, ultrasonic inserts and bio- active retro-filling materials, associated with technological and scientific advances, increased the positive outcomes of this type of treatment from 60% to over 90%. 7 8 Fig. 7: Four-month post-op tomogram of tooth #27. Fig. 8: Four-month post-op tomogram of the mesiobuccal root of tooth #27. roots 2 2021 25

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case report | into the interproximal area to go as deep as possible to the palatal area, if working in the maxilla, from both sides and to elevate the papilla with the tip of the triangle intact (Figs. 1a & b), and it must remain intact. The area in which the flap has been elevated, especially around the tooth, should be kept hydrated so that the fibres can remain in a good condition. Replacing the flap in its original place is crucial. Using a modified technique will allow replacement of the flap and the papilla with slight force, directed coronally that will keep the papilla and the flap in their original places and prevent them from dropping, for the best aesthetic results. Case 1 The patient presented to the office with a swelling in the maxillary anterior (Figs. 2a–d). According to the patient, she had undergone a previous surgery in the area to treat a cyst, and she was told that bone grafting was performed. We placed a gutta-percha cone that led us to the infected area. The radiographs (Figs. 3a–d) and the i-CAT scan (KaVo Kerr) showed us that the pathology was around the apical part of the teeth, one amalgam retro- grade filling had been placed and the area of the bone grafting did not seem right. The patient was very con- cerned about the aesthetics, as she had veneers and did not plan to have them replaced. This added to the challenge of treatment with such inflamed gingiva. The surgery was redone, and the three-month follow-up radiograph and photograph (Figs. 2a–3d) showed great results: the gingiva seemed to be healthy and in place. The six-year follow-up photograph showed the stability of the results and the radiograph the bone healing. Case 2 The patient was referred to our office suffering from swell- ing and pain in the anterior area. According to the pa- 4b 4d 4c 4e 4a Figs. 4a–e: Case 2. tient, she had had the same episode six months before and root canal therapy was done on the lateral incisor. The clinical examination revealed a swelling on top of both the central and the lateral incisor and that a crown had been placed on the central incisor. The radiographs revealed the presence of a large radiolucency in proximity to the nerves and little residual bone (Figs. 4a–e), around 3 mm on the buccal plate between the lateral incisor and the canine. The central incisor had previously undergone apicectomy and had a very large post that would have made retreatment very tricky. A zero apicectomy for the lateral incisor and a normal apicectomy redo for the central apicectomy were per- formed. The postoperative follow-up showed a great result for the papilla, beautiful conservation of the aes- thetics and complete bone healing (Figs. 5a–c). Case 3 The patient was referred owing to failed root canal ther- apy, but this was a misdiagnosed case (Fig. 6), as she was suffering from lateral root resorption alongside a cyst in the apical area above the lateral and the central inci- sor. This infection developed, causing swelling inside her 5a 5b Figs. 5a–c: Case 2. Fig. 5c: 18 months post-op. 5c roots 2 2021 29

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case report | 7 10 8 11 9 12 Fig. 8: The mesial wall was built up with G-ænial A’CHORD (Shade A2, GC). This composite has a fine, silky consistency and does not stick to the instrument, which makes it easy to apply. G-ænial Universal Injectable (Shade A2, GC) was used as a liner at bottom of the approximal box. Figs. 9–11: Undermining cavity areas were built up with everX Flow (Dentin shade) to increase the fracture toughness. The cusps were built up one by one with G-ænial A’CHORD. Fig. 12: Finalised restoration. Note that the enamel was still dehydrated. Conclusion about When restoring posterior cavities, it is important to assess the loss of tooth substance and to select the right materi- als to assure a long-lasting restoration. In large, deep pos- terior cavities, the load-bearing capacity can be increased by using a fibre-reinforced composite (everX Flow) in a suf- ficiently thick layer, covered by a conventional composite. The function of the overlying conventional composite is to give a wear-resistant surface and to provide surface gloss and aesthetics. G-ænial A’CHORD with its simplified uni-shade system and good handling and mechanical properties is the perfect all-rounder for this purpose. Editorial note: A list of references is available from the publisher. Dr Katja Winner-Sowa first graduated as a dental technician in 2001. Soon thereafter, she started her dental studies and graduated in 2007 as a dentist from Goethe University in Frankfurt am Main in Germany. In 2012, she finished her habilitation qualification at the University of Westphalia in Germany. She works as a dentist in Münster, where she has had her own private practice since 2012. In 2013, she obtained a master’s degree in endodontics from the Düsseldorf Dental Academy in Germany. 13 14 Fig. 13: After the occlusion check. Deflective contacts were removed. Fig. 14: After polishing with EVE points (EVE Ernst Vetter). A remarkably high gloss could be obtained with minimal polishing, and the shade blended in very well after rehydration. roots 2 2021 33

news | 1 Fig. 1: The control composite (top) shows bacterial growth after 1 hour and a thick biofilm after 24 hours. The antibacterial filler (bottom) shows broken down bacteria after 1 hour and no live bacteria on the surface after 24 hours, respectively. (All images: © Nobio) that results from shrinkage on polymerisation), debond- ing, technique sensitivity and the degradation of resin by oral bacteria. As reported in a market analysis published by Grand View Research, in the US alone, 200 million cavities are treated every year, and that means about 133 million dental fillings that will fail.3 In an interview with Dental Tribune International (DTI), Prof. Weiss stressed that preventive oral healthcare is the only answer to addressing oral disease, and restorative care cannot do so; however, restorative treatment is a necessity at times. This is where Prof. Weiss and his com- pany Nobio come in, offering a technology that “trans- forms materials, products and surfaces to antimicrobial, with its revolutionary particles, providing strong, safe and durable bio-protection, for life”. How it works In essence, Nobio’s quaternary ammonium silica (QASi) particles exert concentrated electrostatic stress on bac- teria that come in direct contact with the restorative 2 Fig. 2: A detailed illustration of Nobio’s quaternary ammonium silica technology demonstrates how the material works in the oral cavity. roots 2 2021 35

news | 3 Fig. 3: The in situ denture models show the enamel and composite slabs which were used in the University of California, San Francisco clinical trial. a clinical trial that tested the antibacterial composite in 25 patients who wore mandibular partial dentures with acrylic flanges on both sides of the mouth.7 The research- ers recessed a human enamel slab and a composite sep- arated by a tiny gap into the flanges, employing Infinix in one flange and a standard composite as a control in the other. The participants were not aware of which side of the denture contained which composite. This gap model simulated a faulty tooth–restoration interface and then exposed it to cariogenic challenge. After a four-week wearing period, samples were as- sessed in the laboratory using cross-sectional micro- hardness testing of the enamel. The UCSF researchers found that the average mineral loss for the Nobio side was significantly lower (nearly 70%) than for the control side in every patient. key opinion leaders around the world, and according to Prof. Weiss, the feedback has been very positive so far. Perhaps, it is rather paradoxical to ask Prof. Weiss where he thinks the future of dental materials is heading, since it seems that he and his team have just set a new gold stan- dard, but for him, the vision is very clear: “We want every possible material to be equipped with Nobio technology so that patients can benefit from this new generation of mate- rials that can shift the balance towards remineralisation and health.” Indeed, Prof. Weiss confirmed that the company is already working on core build-up materials used in root canal therapy. Orthodontic cements and PMMA-based resins for partial and complete dentures are next on the agenda. Editorial note: A list of references is available from the publisher. Welcome to the future about In late summer 2020, the start-up, which Prof. Weiss founded in 2015 with Dr Julia Rothman, received FDA clearance to commercially distribute Infinix. Reporting on this achievement, local online newspaper the Times of Israel concluded that the clearance “gives Nobio access to the [US] $1.4 billion dental materials market”. In his interview with DTI, Prof. Weiss said that the COVID-19 pandemic had changed the original roll-out plans for the products. Infinix was to have been made available at the end of 2020 in Israel and the US, but that was changed to spring 2021. In the meantime, free prod- uct samples have been distributed to many practising Besides his role at Nobio and many other positions during his career, Prof. Ervin Weiss has trained hundreds of students of dentistry and dental research, published over 150 research articles, and presented more than 200 lectures, abstracts and research studies at international conferences in Israel and abroad. He holds fifteen patents in the fields of dentistry and microbiology. He lives and works in Tel Aviv in Israel, where he runs a dental office specialised in oral rehabilitation together with Dr Michal Dekel-Steinkeller. roots 2 2021 37

news | the site of the restoration, the condition of the remaining tooth structure, the depth and size of the lesion, the possi- bility to isolate, caries risk factors, economic considerations, and the physical and clinical properties of the different restorative options. The comparison table was later trans- formed into a decision tree, and after four further steps, the decision tree was finalised and approved. The decision tree was adapted into a user-friendly online educational tool that aims to facilitate identification of the most suitable restorative materials for each situation. The advice based on the experts’ consensus guides clini- cians step-by-step in identifying the appropriate restorative materials and procedures depending on the clinical situ- ation, taking into account key treatment factors such as time and cost efficiency, aesthetics, patient comfort and expectations, and preservation of tooth structure. According to Prof. Hickel, director of the Department of Operative Dentistry and Periodontology at Ludwig-Maxi- milians University of Munich, the new tool will help dentists to consider the various conditions of patients and teeth involved in dental restorations, and to make decisions on which material to use as an alternative to amalgam. “The phasing down of dental amalgam is happening in nearly all countries. In the European Union a termination may happen in the next five or eight years, but it will hap- pen eventually,” Hickel told Dental Tribune International. He said that a reduction in the use of dental amalgam was “The phasing down of dental amalgam is happening in nearly all countries” —Prof. Reinhard Hickel, Ludwig-Maximilians University of Munich happening at different speeds around the world, and that it was taking place for different reasons. He explained: “In the US, aesthetics has played a role and patients are opting for a more aesthetic restoration. In Scandinavian countries, environmental factors have been a motivating factor in the phase down—for many other countries, toxicity has also been a concern.” Hickel commented that younger clinicians will face fewer hurdles in adapting to the use of new restorative materials. “I would not describe the phase-down as being problem- atic, it will involve new techniques and education is the key. Dentists will have to learn about and gather new experience using a new generation of restorative materials,” he said. The Restorative Options Decision Tree tool can be ac- cessed at https://zingtree.com. Based on experts’ consensus, a new online educational tool helps clinicians in identifying the appropriate restorative materials and procedures. roots 2 2021 39 © David Orcea/Shutterstock.com

news | Linköping University, to ask her what consequences should follow the study findings. She replied: “Our mes- sage is that it is possible to organise work in such a way that prevents injuries. Employers and employees need to get engaged in systematic work environment manage- ment, identify the risks and have a plan on how to handle them. Employers should ask each employee what can be done for him or her to promote health at work. Our results from the study show that employees have different needs and their health clearly varies.” Wåhlin recommends that dental professionals use ergo- nomic exercises in the daily practice to prevent work- related disorders. “Try to bring in more physical and mental variation during your working day. Stand up when you write medical records, use ergonomic work equip- ment, for example prism glasses and good ergonomically designed chairs. Also, test different instruments and use different grips, angle your neck by pulling your chin in to reduce strain on your neck, and instead of bending your back, try to fold from your hip.” Wåhlin has worked as an ergonomist and occupational health and safety consultant at an occupational health ser- vice in Sweden. She said she had become interested in the work environment of dental professionals and that she “provided education to dental professionals on preventive work measures as well as assisted those employees re- turning to work who were absent because of sick leave”. When asked whether the ergonomic aspect of the dental profession—especially in times of SARS-CoV-2 in which the majority of people are concerned about a viral infec- tion rather than physical harm—is too often neglected, she said that dental professionals could certainly become more involved in preventive interventions. “However, we need to evaluate both physical and mental exposure at the same time to see the whole picture, including factors affecting the individual, the group as a whole and the importance of leadership. My impression is that the dental profession has more acute patients in times of SARS-CoV-2 and that this can really affect the work exposure negatively,” she emphasised. She added: “It is also important to angle the patient’s head instead of your own and to dare to fold the dental chair far back. Other helpful tips are to take walking meet- ings and to schedule administrative tasks for the middle of the day. Talk with each other, collaborate to create vari- ation in your work tasks!” The study authors concluded: “Understanding the rela- tionship between working conditions and well-being is crucial to being able to design specific interventions for oral healthcare providers which will improve their working conditions and health. We suggest that future interven- tion studies should focus on how workplace resources influence employee health and well-being.” Editorial note: The study, titled “Work and health charac- teristics of oral health providers who stay healthy at work— a prospective study in public dentistry”, was published online on 6 April 2021 in the European Journal of Physio- therapy, ahead of inclusion in an issue. m o c . k c o t s r e t t u h S / k a z r e c l i a B n c r a M © To reduce strain on the neck and resulting neck pain, it is recommended that the neck be angled by pulling the chin in. roots 2 2021 41

opinion | Besides causing discomfort, back pain caused by incorrect posture and positioning may also undermine clinicians’ confi dence and affect treatment outcomes. do not have enough confidence to correct their posture and positioning, and therefore the incorrect posture and positioning will remain. For the last seven years, I have paid special attention to the topic and discovered some interesting facts. For ex- ample, I now know that the wearing of glasses is one of the main factors affecting posture. Regular reading glasses, provided by an ophthalmologist, have a 22−25 cm focus point. Therefore, the student or practitioner maintains the recommended distance in order to see clearly. Asking for new glasses with a focus point of about 40−45 cm is an easy solution that could help tremendously. Another interesting fact is that practitioners know better than anyone that they have incorrect posture and posi- tioning, yet they do not know how to correct it. The lack of confidence does not allow them to challenge their habits on their own, and so they often seek help. Choosing the right dental care unit Being a member of the dental community, I realised that the first step for many professionals who suffer from back pain is getting a new patient chair. I contacted Planmeca, a well-known dental unit manufacturer based in Helsinki in Finland, to explore its opinion on the topic. Planmeca offers a selection of dental care units with many different configurations. Discussing the issue, Planmeca Senior Vice President Jukka Kanerva explained that the com - pany’s product philosophy has always been that its equipment needs to adapt to the user’s ways of working, not the other way around. Planmeca is a global company, and its products are dis- tributed in over 120 countries. In order to successfully function in all these markets, the company’s dental units have to adapt to different market requirements. “For ex- ample, the preferences of Japanese dentists differ greatly from those of their French colleagues. People come in different shapes and sizes, and dentists like different types of instrument delivery systems,” Kanerva explained. “Also, some like to treat their patients while sitting down, some while standing. This means that the design of the dental unit needs to adapt to several different variables. For this reason alone, our Planmeca Compact i5 dental unit has an almost unlimited number of different cus- tomer configurations available. All our units can also be customised for left-handed users,” he continued. As we can see from Planmeca’s response, manufac- turers are happy to provide practitioners with what is needed. Kanerva assured me that Planmeca follows ergonomic guidelines and studies closely since these are the backbone of its product development process. He commented: “We (Planmeca) also gather feedback from our customers by using many different methods, such as clinic visits by our usability specialists and trade show visits by our sales staff.” “Of course, anyone can submit their ideas through our website, and these submissions are saved in our data- base and analysed. The most common requests are those pertaining to a particular way of working, and these vary from country to country. Ease of use and ergonomics are the key attributes that dentists around the world are roots 2 2021 43

opinion | dure. Not maintaining the most suitable posture for each task will most likely affect the treatment outcome too. To give practitioners guidance on the topic, I started to run courses on posture and positioning on UKDentalCourses (www.ukdentalcourses.com/short-term-cpd). the severity of the pathology, as taking medicine might temporarily make you feel better, but it will not solve the problem permanently. Exercises such as lower back pain exercises, bottom to heels stretches, knee rolls and pelvic tilts could be of help. Studies demonstrate that about 85.5% of clinicians have a forward head posture, whereas 68.8% have a round shoulder posture. For this reason, 36.1% of practitioners In conclusion, a young learner needs to understand the importance of his or her posture and positioning from day one and follow the instructor’s recommendations. m o c . k c o t s r e t t u h S / k a z r e c a B n c r a M © l i Exercises such as stretching could be of help. suffer from scoliosis and hyperlordosis. Most studies on working posture demonstrate a high risk to the lower back and neck. However, appropriate posture muscle strengthening exercises for the neck area can play an important role in minimising this risk. Although it is clear that a dentist’s back pain is mainly caused by an incorrect posture, alternative diagnoses should be ruled out by examining or reviewing the signs and symptoms. If a serious underlying pathology is suspected, the dentist should be referred to the right specialist for relevant guidance. Medication, exercises, surgery and cold or warm therapies are the most com- mon methods of treatment depending on the definitive diagnosis. However, the pain will return if the practitioner does not improve his or her posture and positioning. To remain active in their daily activities, practitioners are advised to take over-the-counter painkillers such as paracetamol or ibuprofen. In my opinion, this depends on Incorrect posture and positioning not only cause dis- comfort such as back pain but also undermine a clini- cian’s confidence and affect treatment outcomes. Existing self-help sources are highly limited, and practitioners need more help on the topic. Dealing with back pain is crucial, and postponing the treatment may result in more complications. about Dr Ali Nankali is a clinical senior lecturer at Barts and the London School of Medicine and Dentistry at Queen Mary University of London and the president of UKDentalCourses, an online education platform that offers continuing professional development opportunities to dentists worldwide. roots 2 2021 45

manufacturer news | The Jeni endodontic motor goes on tour COLTENE travels through Germany with its new workshop programme If you are thinking about buying a new car, you usually try out the object of your desire first, with a test drive. It is much the same when it comes to the fully automatic Jeni endodontic motor from COLTENE, the international dental specialist: dentists can conveniently test- drive the assistance system at a location near them—from a short trip around the block all the way to a day-long road test. Trip around the block or road test? The innovation leader in Germany is taking the new CanalPro Jeni endodontic motor on the road in spring for its major city tour. Because the coronavirus restrictions still pose major challenges for dental practices, COLTENE is offering a new format for further education and training: at a number of locations across the country, dentists will have the opportunity to test-drive the Jeni endodontic motor at a time and place that suits them. In addition to 15 original dates, the company has already announced others. After starting in Germany, the tour will be extended to Europe in the autumn. The choice is between a short test drive of the assistance system as part of a 2.5 hour introduction or an extended road test, that is, a full-day seminar. Both workshops will be led by renowned and expe- rienced endodontic specialists and the COLTENE team of experts and address the special features of the intelligent endodontic motor. While mechanical reprocessing is now an established standard in endodontic practices, CanalPro Jeni works differently to filing motion options known to date and navigates independently through the treatment. Here there are a number of popular sequences to choose from for the flexible nickel–titanium (NiTi) files. The user works forwards continuously from the coronal to apical aspect, applying only slight pressure, while the motor decides on the progress of motion. Based on complex algorithms, the software can control the variable filing motions at millisecond intervals by constantly regulating rotational motion, speed, torque and file stress. This makes the treatment even safer and therefore more comfortable. Endodontic innovations live The course will start with an introduction to the new Jeni repro- cessing system with HyFlex CM and EDM NiTi files. This will be followed by some theory and then a practical session, including numerous hand-on exercises on a practice block and tooth. This way, even endodontic beginners will soon become competent and efficient at reprocessing with the Jeni. Dentists will also receive all relevant information for billing endodontic treatments correctly, profitably and in accordance with legal requirements. To see what dates are currently available please go online to: events.coltene.com. The previous webinars on CanalPro Jeni and the HyFlex and MicroMega file systems can be accessed at any time from the COLTENE webinar archive: COLTENE Mediathek | GoToStage.com. An informative explanatory video on the COLTENE YouTube channel provides an introductory insight into the endodontic motor function- ality: https://youtu.be/Qw3uc3hSTkg. In addition, the COLTENE team of experts is available at all times to advise and support dentists, dental technicians and practice staff. You can contact them via e-mail (info.de@coltene.com) or through one of the social media channels, where you will find questions and answers about specific use or support for optimal application and combination of dental materials and tools. www.coltene.com roots 2 2021 47 Jeni educational videoColtene events

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THE THE ACE ACE LEGACY LEGACY SAFE. EFFICIENT. SOFT CONTROL.