Dental Operating Microscope Research Articles

Surgical endodontics under the microscope: principles and practice

The direct operating microscope has completely revolutionized the field of endodontics, leading to increased success in both non-surgical and surgical cases. In low- and middle-income countries, microsurgical endodontics is still a developing field and procedures that fall within this category employ higher magnification. Currently, less than 25% of dentists in developing countries employ any sort of magnification in their practice. Basic concepts, such as microscope positioning and operator's ergonomics, are still confusing to many dentists, novice or experienced alike. This article introduces the benefits and general principles of direct operating microscope use in endodontic microsurgeries. CPD/Clinical Relevance: A better understanding of the use of dental operating microscopes in endodontic microsurgical techniques may facilitate a more efficient workflow.

Detection of second mesiobuccal canals in maxillary first molars of the Indian population - a systematic review and meta-analysis.

Objective The aim of this systematic review and meta-analysis was to integrate the detection of second mesiobuccal (MB2) canals in maxillary first molars reported by different studies and methods on the Indian population.Methods This systematic review was conducted following Meta-analysis Of Observational Studies in Epidemiology (MOOSE) and PRISMA guidelines. A comprehensive search was conducted in PubMed, Medline, LILACS, Science Direct, Clinicaltrials.gov, CTRI and Cochrane databases to identify manuscripts published until 20 May 2021. Two independent reviewers assessed eligibility for inclusion, extracted data and assessed quality using the Newcastle-Ottawa Scale for cross-sectional studies.Results The database search identified 534 citations, including 36 citations through manual search, and communications from authors. After removing duplicates and going through 534 abstracts followed by 26 full-text articles, 16 articles met the inclusion criteria and contributed data for the review. The included studies used CBCT, radiographs, direct vision (DV), dental operating microscope (DOM) or dental operating microscope with ultrasonic instrumentation (DOMI) for MB2 detection. Meta-analysis and forest plot showed a pooled prevalence of 64.76% of MB2 canals in permanent maxillary first molars using CBCT, 26.5% for DV, 60.4% for using magnification in addition to DV and 71.9% for DV and magnification assisted with ultrasonic instrumentation. The prevalence of MB2 was found to be more in men than women.Conclusion The pooled prevalence in this systematic review and meta-analysis for detection of MB2 canals using CBCT was 64.76% compared to the global prevalence of 73.8%. Further well-designed studies are required to establish maxillary first molar MB2 prevalence in the Indian population.

Robotic and Microrobotic Tools for Dental Therapy.

Robotic and microrobotic tools such as dental operating microscopes and dental endoscopes are being used extensively in dental therapy, which have a significant impact on dental therapy and education. Herein, this paper reviews the state of the art of robotic and microrobotic tools for dental therapy. This article starts with a brief introduction of current robotic and microrobotic tools for dental therapy and then displays their applications in various dental problems; strengths and weaknesses are also surveyed. Lastly, the conclusion and outlook are discussed, referring to the emerging dental clinic problems and demands. This review is expected to provide guidelines for the therapeutic application of robotic and microrobotic tools and to promote the development of robots in dentistry.

Age and experience with dental operating microscope: Do these factors influence on the post space preparation and adhesion of glass fiber posts?

This study evaluated the influence of operator's age and experience with dental operating microscope (DOM) on the cleaning of post space walls and on bond strength of glass fiber posts associated with self-adhesive resin cement. Sixty bovine roots were selected. Root canal preparation was performed and roots were filled using gutta-percha/AH Plus. For post space preparation, specimens were divided into four groups (n=15), according to operator's age and the use of DOM: (1) ≥40 years; (2) ≥40 years with magnification; (3) <40 years; (4) <40 years with magnification. Next, a high-speed bur of the post system and torque-controlled round burs were used for cleaning of post space. Five roots in each group were evaluated for the degree of cleanliness under a stereo microscope using a scoring system. In the remaining 10 specimens from each group, glass fiber posts were cemented with RelyX U200. Two slices (1 ± 0.1 mm) prepared on each root third of all specimens were evaluated by push-out analysis. The scoring system was analyzed using Kruskal-Wallis and push-out data using ANOVA. Significance level was set at 5%. No significant difference was observed in cleaning scores among groups (p > .05). There was no significant difference when comparing the groups and the root thirds (p > .05). The adhesive failure between dentin, cement, and post predominated in all groups. Operator's age and experience with DOM did not influence the cleanliness of root canal walls or the bond strength of glass fiber posts associated with self-adhesive resin cement for post space preparation. RESEARCH HIGHLIGHTS: Although magnification is considered part of Endodontics, little is known about the variables associated. Operator's age and experience with microscope on cleaning of canals and on push-out of posts with self-adhesive resin cement were evaluated.

Validity of the dental operating microscope and selective dentin removal with ultrasonic tips for locating the second mesiobuccal canal (MB2) in maxillary first molars: An in vivo study.

BackgroundSeveral investigations have determined whether the use of a dental operating microscope (DOM) in combination with selective dentine removal with ultrasonic tips increases the percentage of location of the Mesiobuccal 2 (MB2) root canal in maxillary first molars (MFM). However, these studies did not report the performance of in vivo measurements with the comparison with a gold standard. The aim of this study was to determine the validity of the DOM and selective dentin removal with ultrasonic tips to locate the MB2 root canal in MFM using Cone Beam Computed Tomography (CBCT) as the gold standard. Material and MethodsThe initial sample size was 91 patients, but 7 were excluded, so the sample size was 84 patients who signed the informed consent. Inclusion criteria: MFM indicated for root canal treatment. An expert blinded observer identified the MB2 in the CBCT. Two standardized examiners (Kappa=91%) performed the clinical assessment in three stages: Stage 1, canal location with an endodontic explorer and a mirror; Stage 2, use of DOM and Stage 3, use of DOM plus selective dentine removal with ultrasonic tips. The validity of each stage was calculated. ResultsThe prevalence of MB2 using CBCT was 79%, by clinical location was 68%. Sensitivity was 79%, 82%, 86% for stage 1, 2 and 3, respectively. Specificity and Positive Predictive Values were 100% for all methods. Negative Predictive Value was 56%, 60%, 67%, respectively. Positive Likelihood Ratio tends to infinity for all methods, Negative Likelihood Ratio= 0.21, 0.18 and 0.14 and Accuracy= 83%, 86% and 89%, respectively. ConclusionsThe use of DOM with selective dentine removal with ultrasonic tips is the most valid method for locating MB2 canal in MFM. There was an increase in the location of the MB2 root canal with the DOM and ultrasonic tips, which definitely help the clinician. Key words:Cone beam computed tomography, microscopy, second mesiobuccal canal, sensitivity and specificity, validity.

Demystifying Dens Invaginatus: Suggested Modification of the Classification based on a Comprehensive Case Series

Dens invaginatus (DI) is one of the most common developmental anomalies observed in maxillary lateral incisors. An early diagnosis requires thorough clinical knowledge, advanced radiographic evaluation as well as the use of cone beam computed tomography (CBCT) and dental operating microscope (DOM), dictates the successful endodontic management of such teeth. A total of 7 cases with (DI) in maxillary lateral incisors were collected from dental practitioners worldwide, analysed and reported in the present case series. Our aim was to analyse and understand the various morphological patterns of DI in maxillary lateral incisors with their varied treatment protocols employed worldwide. This article illustrates the aberrant morphological patterns and the diverse treatment protocols followed by the clinicians worldwide. The use of biomaterials enhances post-operative healing. Further, a modification in the existing classification has been proposed in this report which would enable the clinicians to easily diagnose, categorise and effectively manage DI. The different treatment protocols employed for the management of DI has been discussed and the use of CBCT and DOM in identifying and managing the anatomical variation of DI were emphasised.

Use of dynamic navigation system in endodontics: A literature review

Over the years, traditional endodontic approaches performed have caused significant loss of healthy tooth structure. Clinical approach became relatively predictable following the introduction of cone-beam computed tomography, Digital Imaging and Communications files, and dental operating microscopes. Despite these advances, mishaps such as excessive dentin loss and/or perforations may still occur during freehand preparations affecting the tooth's prognosis. Following the developments in surface scanning and three-dimensional printing, static guidance systems were introduced. However, they too had multiple drawbacks. Dynamic navigation systems (DNSs) were introduced following to overcome them. DNS is based on computer-aided navigation technology analogous to the Global Positioning System (GPS) navigation. New minimally invasive preparations have been put forward claiming to be the future of endodontics which can be achieved with the help of DNS. The review thus aims at evaluating the possible use of DNS in planning and executing these minimally invasive preparations without unnecessary loss of healthy tooth structure.

AN IN VITRO COMPARATIVE STUDY FOR PREVALENCE OF SECOND MESIOBUCCAL CANAL IN MAXILLARY FIRST MOLAR

Introduction: The root canal structure must be properly cleaned, shaped, and obturated for endodontic therapy to be successful. Clinicians need to be well-versed on root canal morphology to do this. The advent of visual enhancement in endodontics, along with the use of operating microscope has enhanced clinician’s ability to locate all the canals.&#x0D; Objective: The present research aims to evaluate the best method of detection of MB2 canals amongst direct vision (DV), Dental Operating Microscope (DOM) and Cone Beam Computed Tomography (CBCT).&#x0D; Methods: Around 90 human maxillary first molar were used in this study, which were extracted due to caries or had to be extracted due to periodontally weakened condition, were collected from the department of Oral and Maxillofacial surgery, School of dental science, KIMSDU, Karad. Samples were made free of debris and calculus by scaling. All the samples were stored in 0.9% saline before use.&#x0D; Results: In the present study, the detection of second mesiobuccal (MB2) canal was done using three different methods. The prevalence of MB2 by directed vision showed 33.33% cases. The use of operating microscope showed 56.67% presence of MB2 canals in maxillary first molar and use of Cone Beam Computed Tomography (CBCT) showed 86.67% MB2 canals. The prevalence of MB2 by directed vision showed 33.33% cases. Use of operating microscope showed 56.67% presence of MB2 canals in maxillary first molar and use of CBCT showed 86.67% MB2 canals. The present study showed the presence of MB2 was 56.67%.&#x0D; Conclusion: On the bases of the present study one can conclude that CBCT is a promising modality to detect MB2 canals.

Multiple root canals in the maxillary molar: an unusual case report

BackgroundThe objective of this report was to highlight the importance of using a dental operating microscope (DOM) to locate supernumerary canals and diagnose variations in root canals using cone-beam computed tomographic (CBCT) images.Case presentationA 35-year-old Chinese female had repeated swelling in the upper right posterior maxilla for 3 months and was referred to evaluate symptomatic apical periodontitis and mesotaurodonts for upper right first permanent molar and upper right second permanent molar. Root canal therapy was proposed and conducted with the use of DOM and CBCT.ConclusionsProper diagnosis and careful clinicoradiological examination are necessary, and it is essential to reinforce the knowledge of the rare morphology of root canals for clinicians.

Ergonomic Consideration of Sight Shifts between the Microscopic and Macroscopic Environments in Microscopic Dentistry for Inexperienced Operators.

Due to the rising popularity of Dental Operating Microscopes, the issue of their ergonomic use has become an important topic. To verify its impact on dental teams’ ergonomics, the aspect of working in two distinct environments was examined. The research was performed on a group of 82 dentists regarding the number and character of shifts from the microscopic environment to the macroscopic one. The results revealed the shifts constitute a significant part of an inexperienced DOM operator’s work. Because such shifts, when performed repeatedly and in short succession, may influence the operator’s vision and comfort, they should be considered ergonomically detrimental. Having indicated the problem, the article puts forth a solution in the form of an instrument transfer methodology. The proposed adjustment has the potential of improving the quality of work for DOM operators quickly and efficiently by significantly reducing the number of shifts between the environments.

Quality of root canal treatment performed by undergraduate students at the Wits Oral Health Centre

In 2012, the School of Oral Health Sciences at the University of the Witwatersrand modified its undergraduateendodontic curriculum which led to a need to assess the impact of curriculum changes on root canal treatmentoutcomes. This study was an audit of root canal treatment performed by undergraduate BDS students using postoperative radiographs, and compared the results between different undergraduate clinical years of study.Postoperative periapical radiographs of patients treated by undergraduate students were examined to assess length, density and taper. Two independent investigators were first calibrated, and thereafter assessed 299 endodontic cases that were performed by third, fourth and fifth year students during the 2013-2015 period at the Wits Oral Health Centre. 68.9%, 73.6% and 70.9% were found for adequate length, acceptable density and acceptable taper of root filling respectively. The most acceptable length, density and taper results were seen in patients treated by final year students, while the lowest results were observed in the fourth year student cohort. There was a tendency for third year students to overfill due to over-instrumentation of anterior teeth.The change in the curriculum has been justified, though room for improvement exists. The superior result found in the 5th year student cohort was most likely due to their relative experience, and the use of rotary instrumentation and dental operating microscopes. Endodontic teaching should further emphasize the importance of length control during endodontic treatment and more stringent steps may be necessary during patient allocation and clinical supervision of fourth year dental students.

Factors Affecting the Removal Time of Separated Instruments

IntroductionSeparated endodontic instruments may adversely affect the outcome of endodontic treatment. The combination of ultrasonic techniques and dental operating microscopes appears to be effective in the removal of separated instruments compared with more randomized techniques. This study evaluated the roles of root canal curvature and separated instrument length on the time needed to loosen and retrieve the instrument fragments. MethodsThe retrieval procedures of 128 separated instruments referred to a private endodontic practice for retreatment by general practitioners were evaluated in patients who were monitored for a minimum of 6 months. Preoperative cone-beam computed tomographic images were used to measure separated instrument lengths in relation to the degrees of canal curvatures. Ultrasonic instruments were used in the initial phase to remove the tooth structure and to loosen the fractured instrument. In the second phase, ultrasonic instruments, wire loops, or XP Shapers (FKG Dentaire SA, La Chaux-de-Fonds, Switzerland) were used for fragment removal. The time periods for all procedures were recorded. Statistical analysis was completed applying log-normal regression, structural equation modeling, and linear regression using Stata Version 14.2 software (StataCorp LLC, College Station, TX). ResultsAll separated instruments were successfully retrieved. Using the protocol in this study, 89.8% of the instruments were removed using ultrasonic instruments alone with a mean time of 221 seconds. The instrument removal time was dependent on both the instrument length and the root canal curvature. Additionally, preparation times were proportionately longer with increasing separated instrument lengths when the loop device was required. ConclusionsThe preparation phase appears to have an important role in the retrieval of separated instruments. Preparation times for both non-loop and loop groups demonstrate that length and curvature are independent predictors of the log-transformed time. Generally, procedure times were extended with increasing file lengths and higher degrees of canal curvature.

Efficacy of EDDY, passive ultrasonic irrigation and manual irrigation on the removal of orange-brown precipitate

Aim: The aim of this study was to compare the different irrigation activation techniques for removing the orange-precipitate formed after irrigation with sodium hypochlorite (NaOCl) and chlorhexidine (CHX).&#x0D; Methodology: In total, 45-single rooted extracted human teeth were prepared with the ProTaper NEXT rotary system. The roots were respectively irrigated with 5% NaOCl and 2% CHX solutions, and an orange-precipitate formed on the canal walls. The teeth were divided longitudinally, and the precipitate was evaluated with a dental operating microscope (DOM) at 16x magnification before the sections were joined. The halves of roots were then combined, and EDDY, passive ultrasonic activation (PUI) and manual irrigation (MI) techniques were applied for 1 min with 5 ml of distilled water to remove the precipitate. The halves were re-evaluated under the DOM and the residual of percentage of precipitate removed was calculated. The data were evaluated statistically by Kruskal-Wallis tests.&#x0D; Results: A residual orange-precipitate was found in all groups. Although the orange precipitate was effectively removed in the EDDY group, there was no statistically significant difference among EDDY, PUI and MI (p&gt; 0.05).&#x0D; Conclusions: None of the techniques used completely removed the orange precipitate from the root canal surfaces. Among the irrigation activation techniques, there was no superior technique for removing the orange-precipitate from the root canals. &#x0D; &#x0D; How to cite this article: İnce Yusufoglu S, Keskin NB. Efficacy of EDDY, passive ultrasonic ırrigation and manual irrigation on the removal of orange-brown precipitate. Int Dent Res 2021;11(1):1-5. https://doi.org/10.5577/intdentres.2021.vol11.no1.1&#x0D; &#x0D; Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Evaluation of the effectiveness of reciprocal and conventional shaping systems and EDDY and CanalBrush activation systems in calcium hydroxide removal

Aim: To compare the effectiveness of two preparation systems and two irrigation techniques in calcium hydroxide removal from straight root canals.&#x0D; Methodology: Forty-four mandibular premolar teeth were included in this study. The teeth were filled with a calcium hydroxide-based paste and randomly divided into two different preparation groups (Reciproc 50 (R50; VDW, Munich, Germany and ProTaper Universal F5 (PTU; Dentsply Maillefer, Ballaigues, Switzerland). Subsequently, the groups were divided into two subgroups and irrigated using EDDY (VDW, Munich, Germany) and CanalBrush (CB; Roeko, Langenau, Germany) irrigation activation systems. The percentage of calcium hydroxide removed from the canal walls was analyzed using a dental operating microscope (DOM) at 25× magnification. An independent samples t-test, a Mann–Whitney U, Wilcoxon’s tests were used for statistical analysis.&#x0D; Results: There was no significant difference in calcium hydroxide removal throughout the root canal using the R50 and PTU F5 preparation systems (P = 0.847). Both activation systems significantly increased the amount of calcium hydroxide removed from the root canal. Conclusions: EDDY and CB significantly improved calcium hydroxide removal. There was no significant difference between the R50 and PTU F5 systems in calcium hydroxide removal.&#x0D; How to cite this article: Keskin NB, İnce Yusufoğlu S. Evaluation of the effectiveness of reciprocal and conventional shaping systems and EDDY and CanalBrush activation systems in calcium hydroxide removal. Int Dent Res 2021;11(1):16-22. https://doi.org/10.5577/intdentres.2021.vol11.no1.4&#x0D; &#x0D; Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Accidental nasal fossa perforation during endodontic treatment - Case report

Fracture of an endodontic instrument within the root canal system can occur due to incorrect use of instruments, and clinicians are confronted with a few removal options when considering this situation. The purpose of this article is to present the removal of a fractured endodontic file from the periapical region of the right upper central incisor, that caused a nasal floor perforation and otorhinolaryngological symptoms, with the aid of a dental operating microscope (DOM) and cone bean computed tomography (CBCT). Success was achieved when the fragment was visible and removed from the nasal fossa. The standardized techniques of removal or bypassing fracture file were not effective, and success was obtained with the aid of CBCT that made possible the visualization of the broken file inside the nasal fossa.

In vitro study to compare the accuracy of four diagnostic methods for locating the second mesiobuccal canal in maxillary molars

The aim of this in vitro study is to compare the efficacy of three diagnostic methods, Direct visual method, Magnifying loupes and Dental operating microscope in recognising all the canals of the root canal system in maxillary first molars using CBCT and reference standard method. A total of 65 maxillary first molars were selected for this study. Teeth selected were evaluated by Periapical radiographs and CBCT. Access cavities of selected extracted human maxillary first molars were prepared, and the floor of the pulp chamber was then explored to locate the MB2 canal in five stages: Stage I (Direct Visual Method), Stage II (under ×3.5 Magnifying Loupes with light-emitting diode [LED] light), Stage III (Under Dental Operating Microscope), and Stage IV (Cross-sectioning was done below CEJ and the sections were evaluated using stereomicroscope at 10x magnification). The descriptive statistics were tabulated using Chi square test to compare the efficacy between the diagnostic methods. Senstivity, specificity, Positive /Negative predictive values were calculated for each method. The results obtained in this study showed that CBCT was most accurate with the dimensional accuracy of 96% followed by Dental operating microscope which performed better (with the diagnostic accuracy of 76%) than the magnifying loupes (with the diagnostic accuracy of 64%) direct visual method (with the diagnostic accuracy 60%). The dental operating microscope was most effective in the detection of MB2 canals followed by magnifying loupes and direct visual method. Additionally, CBCT could be used as a supplementary diagnostic tool in cases in which canals are not found using the methods available in the dental office.

An Update on Endodontic Microsurgery of Mandibular Molars: A Focused Review.

Endodontic microsurgery is a highly predictable treatment option in most cases when conventional endodontic treatment is not feasible. Nevertheless, mandibular molars are still considered by clinicians to be the most difficult type of teeth, with the lowest success rate. In recent years, endodontic microsurgery has been attempted more frequently with the emergence of modern cutting-edge technologies such as dental operating microscopes, various microsurgical instruments, and biocompatible materials, and the success rate is increasing. This review describes the current state of the art in endodontic microsurgical techniques and concepts for mandibular molars. Notably, this review highlights contemporary equipment, technology, and materials.

The instrument transfer method in four handed dentistry in dental operating microscope as a module of a training program in the aspect of reduction of the dynamic load of the visual system of the operator

Resume. Introduction of a Dental Operating Microscope (DOM) in the clinical work can make some difficulties in operator’s work.In particular, to ensure the safety of the operator’s visual system and ergonomics of the work, the operator’s gaze should be continuously directed to the operating field. The instruments should be moved over the operating field by the assisting personnel, whose participation in the transfer is not complete until the evening nstrument is visible through the microscope and the operator is fully capable of controlling its movement. Instrument transfer method in DOM includes 3 steps: modified direct placement, predelivery, delivery and exchange of instruments. In the presented method the most important elements are the properly oriented end of the instrument by dental assistant and mutual grasp of instrument. The method allows to reduce the load on the operator’s visual system and to make four-handed work ergonomic. Key words: dental operating microscope (DOM), four-handed dentistry in DOM, instrument transfer in DOM, mutual grasp, visual system overload of dental operator.

Endodontic management of permanent mandibular first molar with middle mesial canal: A case report

Endodontic treatment of a permanent mandibular first molar is often difficult due to its related complex variations. The root cause of endodontic failure is the inability of a practitioner to recognize and manage an irregular root canal system. Knowledge of dental anatomy, thorough examination, and utilization of recent diagnostic tools are required for an effective root canal treatment. A 31-year-old Saudi male patient presented to the endodontic clinic for endodontic treatment of the mandibular left first molar (#36). Clinical examination using a dental operating microscope (DOM) followed by radiographic examination including cone-beam computed tomography (CBCT) revealed the diagnosis of asymptomatic apical periodontitis in a previously attempted root canal therapy which was incomplete. The periapical disease involved middle mesial canal (MMC) intermingling with the mesiobuccal (MB) in the mesial root. The root canal treatment was successfully carried out with no symptoms during 6 months of follow-up period. This case reports the presence of unusual presentation of MMC and MB canal in the mandibular first molar, which had resulted in postendodontic complications, which was diagnosed using CBCT and successfully managed with good prognosis. Dentists can use technical and imaging advancements including the DOM and CBCT to recognize anatomical variations in the root canal system, especially in cases of postendodontic failures or complications.

A Comparative Clinical Evaluation of Access Cavity Preparation Using Dental Operating Microscope and Conventional Preparation for Conservation of Tooth Structure

A Comparative Clinical Evaluation of Access Cavity Preparation Using Dental Operating Microscope and Conventional Preparation for Conservation of Tooth Structure