Endodontic Access Cavity Preparation Research Articles

Minimally invasive access cavities in endodontics

Background: The access cavity is a critical stage in root canal therapy and it may influence the subsequent steps of the treatment. The new minimally invasive endodontic access cavity preparation concept aims to preserve sound tooth structure by conserving as much intact dentine as possible including the pulp chamber's roof, to keep the teeth from fracturing during and after endodontic treatment. While there is great interest in such access opening designs in numerous publications, still there is a lack of scientific evidence to support the application of such modern access cavity designs in clinical practice. This review aims to critically examine the literature on minimal access cavity preparations, explain the effect of minimally invasive access cavity designs on various aspects of root canal treatment, and identify areas where additional research is required. Data: An electronic search for English-language articles was performed using the following databases: Google Scholar, PubMed, and Research Gate. The following keywords were used: "minimally invasive access cavity", "conservative endodontic cavity ", and "classification of access cavity". Study selection: 64 papers that were the most relevant to the topics in this review were selected between 1969 to 26 February 2022. Conclusions: Minimally invasive access cavities can be classified into conservative, ultraconservative, truss access, caries and restorative-driven cavities. There is a deficiency of proof that a minimally invasive access cavity maintains the resistance to fracture of endodontically treated teeth greater than traditional access cavities. There was no difference in the percentage of untouched walls and debris removal in teeth with conservative vs traditional access cavities, however, truss and ultraconservative access cavities resulted in poor irrigation efficacy compared to traditional ones. Also, the lower cyclic fatigue resistance of rotary instruments and root canal obturation with voids were associated with minimally invasive access cavities. The studies about minimally invasive access cavities still have a wide range of methodological disadvantages or register unsatisfactory or inconclusive results. Therefore, further research on this topic is needed especially with the everyday advancement of techniques and armamentarium used in endodontics.

Three-dimensional software adapted to evaluate endodontic access cavity preparation.

Three-dimensional software adapted to evaluate endodontic access cavity preparation.

Effect of Different Endodontic Access Cavity Designs in Combination with WaveOne Gold and TruNatomy on the Fracture Resistance of Mandibular First Molars: A Nonlinear Finite Element Analysis

IntroductionThis study evaluated the effect of traditional and conservative endodontic access cavity designs in combination with WaveOne Gold and TruNatomy instrumentation systems on the fracture resistance of mandibular first molars by means of nonlinear finite element analysis (FEA). MethodsMicro-CT images of 4 human mandibular first molars were used to generate representative FEA models. The mandibular first molars samples were scanned before and after endodontic access cavity preparation and instrumentation of all 3 canals. Five nonlinear static loads were applied vertically and horizontally to specific contact points on the occlusal surface of the teeth. Maximum von Mises stress before failure and distribution of von Mises strains were recorded and compared between groups. ResultsMolars with conservative endodontic access cavities required similar levels of loads to reach failure compared with their control samples, whereas molars with traditional endodontic access cavities required significantly reduced loads in order to fail. According to the numerical investigation, the type of instrumentation system was found to have an insignificant effect on the fracture resistance of the teeth under study. Von Mises stress was concentrated around the cervical region and in the larger distal roots for all numerical models. ConclusionsThe fracture resistance of mandibular first molars is influenced significantly by a reduction in dental hard tissue, which was found to control the level of the ultimate failure load for each tooth.

Accuracy of Guided Endodontics in Posterior Teeth

The purpose of this ex vivo study was to determine the accuracy of template-based guided endodontics for access cavity preparation and root canal detection in posterior teeth. First, three maxillary and four mandibular models were constructed using 67 premolars and molars, with a total number of 135 main root canals. Cone beam computed tomography (CBCT) and three-dimensional 3D surface scans of each model were performed and matched in order to plan access cavity preparation and design templates virtually. Template-guided access cavity preparation was then performed for each tooth, followed by postoperative CBCT scanning. Deviations between planned and prepared access cavities were measured after superimposition of the pre- and postoperative CBCT scans, and they were analyzed using descriptive and multivariate statistics. All root canals (135/135) were detected utilizing guided endodontics. The mean angle deviation was 1.4 degrees, and the mean deviations at the tip and base of the bur were 0.24–0.31 mm and 0.26–0.29 mm, respectively. This study demonstrated that guided endodontics is an accurate and predictable method for endodontic access cavity preparation in posterior teeth.

Impact of Virtual Reality Simulation in Endodontics on the Learning Experiences of Undergraduate Dental Students

We aimed to evaluate the impact of Virtual Reality Dental Simulators (VRDS) on preclinical training in endodontics for undergraduate dental students. Purposive sampling technique was used to target undergraduate dental students at two dental schools: in Qatar and Turkey. After training on endodontic access cavity preparation on upper anterior teeth using acrylic teeth on dental mannequins and virtual reality haptic dental simulator, a questionnaire based on a combination of open- and closed-ended items was distributed to the participants. The sample included 60 dental undergraduate students. The participants reported positive experiences with VRDS and 76% considered it to be helpful in improving their fine motor skills. Endodontic access cavity preparation on VRDS was perceived to be similar to natural and acrylic teeth by 73.34% and 53% of participants, respectively. Overall, 85% of participants supported the use of VRDS training to supplement conventional training on dental mannequins but also recommended the need for improvements in VRDS training in endodontics. The findings of this study underscore the benefits of VRDS in endodontics. Future research involving larger samples from multiple institutions may help to optimize VRDS in undergraduate dental education.

Comparison of Fracture Resistance of Endodontically Treated Teeth With Traditional Endodontic Access Cavity, Conservative Endodontic Access Cavity, Truss Endodontic Access Cavity, and Ninja Endodontic Access Cavity Designs: An In Vitro Study

Introduction: Endodontic access cavity preparation plays a vital role as preservation of enamel structure is of utmost importance for a tooth's strength to be maintained. As teeth become fragile after a root canal therapy, this study was designed to compare in vitro the fracture resistance of root-filled and restored teeth with traditional endodontic access cavity, conservative endodontic access cavity (CEC), ninja endodontic access cavity (NEC), and truss endodontic access cavity (TEC).Materials and methods: Control (intact teeth) and traditional endodontic access cavity as well as CEC, NEC, and TEC groups were each given a new human mandibular molar that was freshly removed. Cone beam computed tomography (CBCT) scans of the cone beam showed the values of CEC, NEC, and TEC. After that the teeth were endodontically treated and repaired. To test the specimens, universal testing equipment was used. In order to avoid tooth breakage, the maximum load was determined. Statistical analysis was used in the form of Kolmogorov-Smirnov and Levene tests, which were used to examine data for typical dispersion and consistency in change.Results: Intact teeth showed the highest resistance to fracture compared with other groups. TEC showed significantly higher resistance to fracture compared to the CEC design.Conclusions: It is possible, within the restrictions of this research, to infer that the TEC design enhanced tooth fracture strength in comparison with the CEC design.

Assessment of the educational value of endodontic access cavity preparation YouTube video as a learning resource for students.

ObjectiveTo evaluate the educational value of YouTube as a learning tool for dental students regarding endodontic access cavity preparation.Methods and findingsYouTube search was made for videos related to endodontic access cavity preparation using specific terms. After exclusions, 41 videos were chosen and assessed for tooth type, video length, days since upload, country of origin, number of views and likes, source of authorship, and viewing rate. To grade the content of videos, a usefulness score with seven elements was developed. Each element was given a score of 0 or 1. Statistical tests were run by using Kruskal-Wallis and Mann-Whitney tests (SPSS Inc, Chicago, IL, USA) at a 5% significance level. The videos received a mean of 181198.5 views with a mean duration of 686.1 seconds. The mean number of “likes” was 1047.8. Almost half of the videos covered content related to molar teeth. Most videos were provided by health care professionals with almost 50% uploaded from India. The mean usefulness score was 4.29 (range: 1–7) and the most discussed elements were description, instruments used, access cavity demonstration, and evaluation criteria. About a quarter of the videos were classified as good, while 46.3% as moderate and 29.3% as poor. Among the content usefulness categories, no difference was found in the video demographics (p>0.05) except “days since upload” (p = 0.018) in which good quality videos were found to have the highest median. Moreover, although insignificant, good videos were found to have the longest duration and lowest number of views, likes, and viewing rate. The mean usefulness score of videos released during the COVID-19 pandemic was lower than that for pre-pandemic videos (p = 0.042), and videos uploaded by academic institutions had a higher mean usefulness score than videos uploaded by health care professionals (p<0.001).ConclusionsInformation on endodontic access cavity preparation is not comprehensive in most of the reviewed YouTube videos and could be of low educational value.

Guided Endodontics: Three-dimensional Planning and Template-aided Preparation of Endodontic Access Cavities.

Pulp canal obliterations (PCO) are often a consequence of dental trauma, such as luxation injuries. Even though dentin apposition is a sign of vital pulp, pulpitis or apical periodontitis may develop in the long term. Root canal treatment of teeth with severe PCO and pulpal or periapical pathosis is challenging for general practitioners and even for well-equipped endodontic specialists. To ensure detection of the calcified root canal and avoid excessive loss of tooth structure or root perforation, static navigation using templates ("Guided Endodontics") was introduced a few years ago. The general workflow includes three-dimensional imaging using cone-beam computed tomography (CBCT), a digital surface scan, and superimposition of both in a planning software. This is followed by virtual planning of the access cavity and the design of a template that will guide the drill to the desired target point. To do this, a true-to-scale virtual image of the drill must be placed in a way that the tip of the drill reaches the orifice of the calcified root canal. Once the template has been fabricated using computer-aided design and computer-aided manufacturing (CAD/CAM) or a 3D printer, guided preparation of the access cavity can be performed clinically. For research purposes, a postoperative CBCT image can be used to quantify the accuracy of the access cavity performed. This work aims to present the technique of static guided endodontics from imaging to clinical implementation.

Guided Endodontics: Three-Dimensional Planning and Template-Aided Preparation of Endodontic Access Cavities

Guided Endodontics: Three-Dimensional Planning and Template-Aided Preparation of Endodontic Access Cavities

Current strategies for conservative endodontic access cavity preparation techniques-systematic review, meta-analysis, and decision-making protocol.

To assess related studies and discuss the clinical implications of endodontic access cavity (AC) designs. A systematic review of studies comparing the fracture resistance and/or endodontic outcomes between different AC designs was conducted in two electronic search databases (PubMed and Web of Science) following the PRISMA guidelines. Study selection, data extraction, and quality assessment were performed. Meta-analyses were undertaken for fracture resistance and root canal detection, with the level of significance set at 0.05 (P = 0.05). A total of 33 articles were included in this systematic review. The global evaluation of the risk of bias in the included studies was assessed as moderate, and the level of evidence was rated as low. Four types of AC designs were categorized: traditional (TradAC), conservative (ConsAC), ultraconservative (UltraAC), and truss (TrussAC). Their impact on fracture resistance, cleaning/disinfection, procedural errors, root canal detection, treatment time, apical debris extrusion, and root canal filling was discussed. Meta-analysis showed that compared to TradAC, (i) there is a significant higher fracture resistance of teeth with ConsAC, TrussAC, or ConsAC/TrussAC when all marginal ridges are preserved (P < 0.05), (ii) there is no significant effect of the type of AC on the fracture resistance of teeth when one or two marginal ridges are lost (P > 0.05), and (iii) there is a significantly higher risk of undetected canals with ConsAC if not assisted by dental operating microscope and ultrasonic troughing (P < 0.05). Decreasing the AC extent does not necessarily present mechanical and biological advantages especially when one or more surfaces of the tooth structure are lost. To date, the evidence available does not support the application of TrussAC. UltraAC might be applied in limited occasions. Maintaining the extent of AC design as small as practical without jeopardizing the root canal treatment quality remains a pragmatic recommendation. Different criteria can guide the practitioner for the optimal extent of AC outline form which varies from case to case.

Real-Time Guided Endodontics with a Miniaturized Dynamic Navigation System Versus Conventional Freehand Endodontic Access Cavity Preparation: Substance Loss and Procedure Time

IntroductionThis study aimed to evaluate substance loss and the time required for access cavity preparation (ACP) using the conventional freehand method (CONV) versus a miniaturized dynamic navigation system of real-time guided endodontics (RTGE) in an in vitro model using 3-dimensional–printed teeth. MethodsNine human anterior maxillary teeth were selected and micro–computed tomographic scanned. Root canals were virtually reduced to 2 mm below the cementoenamel junction. The teeth were digitally duplicated and mirrored to yield 6 different models with 6 single-rooted teeth each. The models were 3-dimensionally printed using radiopaque resin and consecutively mounted on a dental mannequin for ACP. Two operators with 12 and 2 years of clinical experience, respectively, received 6 models (36 teeth) each and performed ACP on half of the models using RTGE (after digital planning) and CONV on the other half 2 weeks later. The time was recorded. Postoperative substance loss was measured by cone-beam computed tomographic imaging. The differences in time and substance loss between the methods and operators were evaluated by the t test. ResultsOverall, substance loss was significantly lower with RTGE than CONV (mean = 10.5 mm3 vs 29.7 mm3), but both procedures took a similar time per tooth (mean = 195 vs 193 seconds). Operator 1 (more experienced) achieved significantly less substance loss than operator 2 with CONV (mean = 19.9 vs 39.4 mm3) but not with RTGE (mean = 10.3 vs 10.6 mm3). ConclusionsRTGE is a practicable, substance-sparing method performed in comparable time as CONV. Moreover, RTGE seems to be independent of operator experience.

COMPARATIVE STUDY OF ANTIBACTERIAL ACTIVITY OF PHOTOACTIVATED DISINFECTION WITH FOTOSAN AND STANDARD ENDODONTIC TREATMENT

Introduction: The purpose of endodontic treatment is to eliminate the bacterial infection in the root canal system and allow healing of apical periodontitis. Sometimes the anatomical complexity of the root canal system makes complete removal of bacteria almost impossible even if the conventional methods of chemo-mechanical debridement are performed strictly according to the protocol. So additional methods of root canal disinfection can be applied such as photoactivated disinfection (PAD). Purpose: The aim of our study was to compare the antibacterial activity of PAD with FotoSan, and conventional endodontic therapy in the treatment of infected root canals. Materials and methods: The study involved 36 teeth of patients who are diagnosed with pulp necrosis or with the periapical chronic periodontitis and require endodontic treatment and divided into two groups of 18 teeth each. The first microbiological sample was taken by placing a sterile paper point in the root canal, after endodontic access cavity preparation. All root canals are prepared by Protaper Universal rotary instruments (Maillefer Instruments SA, Ballaigues, Switzerland). In the first group, the disinfection of the root canals was made with photoactivated disinfection with FotoSan. In the second group was performed the endodontic treatment with the standard protocol of irrigation - 2.5% sodium hypochlorite solution and 17% EDTA. After that, the root canals are dried with sterile points, and a second microbiological sample is taken. Results: In all compared pairs, there was no significantly different effect regarding the number of microorganisms. Conclusions; The disinfection with NaOCl has the strongest antimicrobial effect in this study. Second place is occupied by PAD with FotoSan. We believe that the established antimicrobial effect of PAD make the method appropriate as complementary to routine endodontic treatment.

Suitability of Magnetic Resonance Imaging for Guided Endodontics: Proof of Principle

IntroductionThis proof-of-principle study aimed to demonstrate that magnetic resonance imaging (MRI) is sufficiently accurate for the detection of root canals using guided endodontics. MethodsOne hundred extracted human teeth (anterior and premolar) were mounted onto 5 mandibular and 5 maxillary models, fitted with splints designed to accommodate a thin layer of aqueous gel for indirect imaging, and scanned by MRI. After MRI and intraoral scans were aligned using planning software, access cavities were planned virtually, and templates were manufactured with computer-aided design/computer-aided manufacturing, the access cavities were prepared. Cone-beam computed tomographic scans were performed and matched with the virtual preoperative planning data to determine the accuracy of access cavity preparation in terms of deviation between planned and prepared cavities in the mesiodistal and buccolingual dimensions and angle. Descriptive statistical analysis was performed, and the mean values were compared using the t test. ResultsNinety-one of 100 root canals were successfully scouted after MRI-guided access cavity preparation. The mean angle deviation was 1.82°. The mean deviation ranged from 0.21–0.31 mm at the base of the bur and from 0.28–0.44 mm at the tip of the bur. Preparation in the buccolingual dimension was significantly more precise in mandibular compared with maxillary teeth, and accuracy in the mesiodistal dimension was more precise in anterior teeth compared with premolars. ConclusionsThis in vitro study demonstrated the suitability of MRI for guided endodontic access cavity preparation.

Application of CBCT data and three-dimensional printing for endodontic diagnosis and treatment: Three case reports

The combined CBCT and 3-d printing have found its endodontic application in pre-surgical planning models, endodontic access guides and localization of osteotomy preparation site. This article reports a series of three cases where this combined technology have been used. The first case report is of radicular dens invaginatus which was diagnosed by using cone-beam computed tomography (CBCT) imaging and 3D plastic models of the tooth. The case was managed successfully by the combination of both surgical and non-surgical endodontic treatment. The second case report is the guided access preparation of lower anterior teeth. A 3D printed template was designed with the CBCT scan for the guided access cavity preparation and was compared with the conventional endodontic access cavity preparation. The third case report is the surgical template guided hemisection. A 3D surgical template was designed which allowed precise angulation of the bur and minimized the excess removal of tooth structure. Thus, the combined use of CBCT and 3D printing enabled visualization of complex root canal anatomies and allowed precise and accurate treatment.

Minimization of Tooth Substance Removal in Normally Calcified Teeth Using Guided Endodontics: An In Vitro Pilot Study

IntroductionThis study evaluated the success rate of and tooth substance removal required for computer-guided preparation of endodontic access cavities. MethodsThirty acrylic typodont teeth with root canals (10 each of tooth numbers 11, 14, and 17) were randomly allocated to a study or control group (15 teeth per group). In the study group, teeth were fixed in acrylic resin and subsequently digitized using a laboratory scanner. A cone-beam computed tomographic scan was then taken. Access cavity preparations were planned virtually, and a template was 3-dimensionally printed. In the control group, access cavities were prepared using the conventional access technique. Tooth substance removal was assessed by weighing teeth before and after preparation. Volume loss was analyzed statistically by use of the Wilcoxon-Mann-Whitney test at a significance level of P < .05. ResultsUsing guided endodontics, 93.3% of root canals were located successfully compared with 100% of root canals using the conventional technique. In the control group, the mean tooth substance removal was 16.1 ± 3.7 mm³ for incisors, 44.2 ± 8.9 mm³ for premolars, and 99.3 ± 3.1 mm³ for molars. In the study group, significantly less tooth substance was removed; substance loss was 10.3 ± 1.1 mm³ for incisors, 29.3 ± 4.2 mm³ for premolars, and 51.8 ± 5.3 mm³ for molars. ConclusionsThe use of guided endodontics in normally calcified teeth enables the preservation of a significant amount of tooth substance. However, this advantage must be carefully balanced against a greater radiation burden and risk of perforation, higher costs, and more difficult debridement and visualization of the pulp chamber and root canals.

Effect of access cavity design on gaps and void formation in resin composite restorations following root canal treatment on extracted teeth.

To evaluate the influence of ultraconservative endodontic access cavities (UEC) on gaps and void formation in resin composite restorations in extracted two-rooted maxillary premolars after root canal treatment. Traditional endodontic access cavities (TEC) were used as a reference for comparison. Two-rooted maxillary premolars were scanned in a micro-computed tomographic (micro-CT) device, matched based on similar anatomical features and allocated into two groups (n=10) according to the design of the access cavity: TEC or UEC. Teeth were mounted on a mannequin head and a single operator performed the treatment, including endodontic access cavity preparation, root canal detection, preparation, filling and restoration procedures, under magnification. For restorative procedure, a bulk fill flowable layer was applied initially followed by an overlaying of regular composite. After restoration procedures, a new micro-CT scan was performed to check the quality of the coronal restoration by analysing the percentage volume of empty spaces present in the tooth-restoration interface (gaps) and inside the restoration (voids). Data were analysed statistically using Shapiro-Wilk and Student's t tests with a significance level of 5%. All specimens had gaps and voids. There were significant differences between the access cavity designs regarding the formation of voids with significantly more voids associated with the UEC (P<0.05). Gap formation did not differ between groups (P>0.05). The access cavity design used during root canal treatment interfered with the adaptation of the restorative material. The minimally invasive access cavity design was associated with a significantly greater number of voids within restorations.

Influence of minimally invasive endodontic access cavities on root canal shaping and filling ability, pulp chamber cleaning and fracture resistance of extracted human mandibular incisors.

To evaluate the influence of the location and design of endodontic access cavities on root canal shaping and filling ability, pulp chamber cleaning and fracture resistance of extracted human mandibular incisors. After pre-selection using periapical radiographs, forty extracted intact human mandibular incisors were scanned in a micro-computed tomographic device. The teeth were matched based on similar anatomical features of the canals and assigned to four experimental groups (n=10) according to the endodontic access cavity and root canal preparation protocol: traditional/TRUShape (T/TRU); traditional/MTwo (T/MT); minimally invasive/TRUShape (MI/TRU); and minimally invasive/MTwo (MI/MT). The samples were scanned after root canal instrumentation and filling procedures. The parameters evaluated were as follows: volume and area of the root canal, noninstrumented canal areas, canal transportation and centring ratio, accumulated hard tissue debris, voids in root canal fillings and remnants of root canal filling materials in the pulp chamber. After root canal filling and cavity restoration procedures, the samples were submitted to a fracture resistance test. Data were statistically analysed using Shapiro-Wilk, one-way anova and Bonferroni tests with a significance level of 5% (α=0.05). There was no difference regarding all parameters evaluated before and after root canal preparation (volume and area of the root canal, noninstrumented canal areas, canal transportation and centring ratio, and accumulated hard tissue debris) amongst the groups (P>0.05). MI/TRU and MI/MT groups were associated with significantly more voids in root canal fillings when compared to the T/TRU and T/MT groups (P<0.05). Percentage of root canal filling material remnants in the pulp chamber after cleaning procedures and mean fracture resistance values were not significantly different amongst the four experimental groups (P>0.05). The location and design of the endodontic access cavity did not impact on root canal preparation nor resistance to fracture of extracted mandibular incisors, regardless of the instrument used. Minimally invasive access cavities were associated with significantly more voids in root canal fillings.

In Vivo Strain Alterations in Mandibular Molars after Root Canal Treatment Procedures

IntroductionThe aim of this investigation was to determine the coronal strain variations in mandibular molars under an in vivo bite load after root canal treatment procedures. MethodsThe coronal strain in carious mandibular first molars with symptomatic irreversible pulpitis (experimental group) was compared with that of intact contralateral teeth (control group) in patients 20–40 years old. Experiments were conducted in 2 stages. In stage 1, the maximum bite force on the first molar region was determined on the experimental and control teeth using a customized load cell. In stage 2, strain gauges were bonded to the buccal aspect of teeth, and the strain was recorded after the application of a bite load on the intact (control) teeth; and the experimental teeth before and after endodontic access cavity preparation, cleaning/shaping procedures, root filling, and composite core restoration. ResultsThe mean maximum bite force on the experimental teeth (91 ± 48 N) and the contralateral control teeth (91 ± 49 N) was not significantly different (P = .989). The preoperative strain (microstrain) in the experimental teeth was significantly higher (125 ± 36, P = .001) than in the contralateral intact teeth (46 ± 17). Access cavity preparation significantly increased the strain (327 ± 98, P = .019) on the experimental teeth compared with the preoperative strain. Cleaning/shaping (355 ± 113) and root filling (346 ± 89) did not significantly increase (P = 1.00) the strain compared with the strain determined after endodontic cavity preparation. Composite core restoration in the experimental teeth (106 ± 41) resulted in a significant reduction in the strain compared with the values recorded after an endodontic access cavity (P = .002) and was similar to the preoperative strain values (P = 1.00) but was significantly higher than the strain values in contralateral intact teeth (P = .001). ConclusionsThe coronal strain on the buccal surface of mandibular first molars significantly increased with access cavity preparation, which did not increase further after cleaning/shaping or root filling. A significant reduction in the strain induced by root canal treatment steps was evident after composite core restoration.

Standardization of Endodontic Access Cavities Based on 3-dimensional Quantitative Analysis of Dentin and Enamel Removed

IntroductionThe aim of this study was to determine and compare the difference in the volume of dentin and enamel removed (DER) to prepare 3 different access cavities and to propose a standardization of the access cavities according to their volume of DER. MethodsOne hundred twenty maxillary and mandibular molars and premolars were assigned to 3 subgroups for each tooth type (n = 10): the traditional endodontic cavity (TEC) group; the conservative endodontic cavity (CEC) group with partial unroofing and convergent walls; and the ultraconservative endodontic cavity (UEC) group, preserving most part of the pulp chamber roof and the occlusal surface. The sliced image data of cone-beam computed tomographic images before and after access cavity preparation were exported as Digital Imaging and Communications in Medicine files and imported into the MeVisLab framework system (MeVis Research, Bremen, Germany). After segmentation, the volumes of coronal dentin and enamel were measured, and the difference in the percentage of volume of DER for endodontic access cavity preparation was calculated. The data were subjected to statistical analyses (analysis of variance) with a level of significance set at P < .05. ResultsThe percentage of volume of DER was less than 6% for the UEC group, up to 15% for the CEC group, and more than 15% for the TEC group, with a statistically significant difference among all groups in all of the tooth types analyzed (P < .05). ConclusionsThe present study showed significantly different percentages of volume of DER among the groups analyzed (ie, UEC < CEC < TEC). A standardization of access cavity preparation was proposed according to the percentage of volume of DER.

Student perceptions of clinical experiences in endodontic access cavity preparations

ABSTRACT OBJECTIVES: The aim of this study was to gain understanding into the perceptions of undergraduate dental students regarding their levels of competence and confidence when preparing endodontic access cavities MATERIALS AND METHOD: Anonymous survey forms were given to 100 undergraduate dental students at Sefako Makgatho Health Sciences University, School of Oral Health Sciences. Students were asked to indicate their self-confidence level by using a 5-point Likert scale as 'not confident', 'manageable', 'comfortable and confident',' extremely confident' and 'never done it'. RESULTS: The response rate was 75 % out of 100 students. The majority of the participants (88%) indicated that they would perform endodontic access cavity preparation with ease on anterior teeth and the lowest (43%) confidence levels was indicated on multi-rooted posterior teeth Keywords: Perceptions, clinical experiences, endodontic access cavity preparation, teaching and learning.