Canal In Maxillary First Molars Research Articles

Comparison of hand, rotary, reciprocating and self-adjusting files in cleaning mesio-buccal canals of maxillary first molars.

The smear layer removal capability of different instrumentation techniques on the mesio-buccal root canals of maxillary first molars is of interest to dentists. Sixty extracted maxillary first molars with fully developed apices, curved root canals, and curvatures between 30 to 45 degrees were selected. The teeth were divided into four groups (n=15) based on the instrumentation technique used. The samples were analyzed using a thermal field emission scanning electron microscope to assess smear layer removal at the apical, middle, and coronal thirds of the canals. The Wave One file system showed superior performance in smear layer removal across all three regions of the canal compared to hand files, Hyflex CM rotary files and SAF.

Morphology and classification of the second mesiobuccal canal in maxillary first molars: a cone-beam computed tomography analysis in a Chinese population

BackgroundUnderstanding the tooth anatomy is crucial for ensuring effective endodontic treatment. This study investigated the root canal morphology of the second mesiobuccal (MB2) canal in maxillary first molars (MFMs) in a Chinese population using cone-beam computed tomography (CBCT).MethodsThis study evaluated 486 MFMs with MB2 canals from 285 participants undergoing CBCT examination and determined the Vertucci’s classification and position of the MB2 canal orifice. The prevalence of the MB2 canal was correlated with the sex, age, and tooth side. The correlations between the prevalence of the MB2 canal and sex and tooth side were assessed using the Fisher's exact test. The chi-square test was used for evaluating the correlation between the prevalence of the MB2 canal and age.ResultsThe number of type II, III, IV, V, VI, VII, and other root canals in the MFMs was 30.9%, 0.6%, 65.0%, 1.2%, 1.2%, 0.4%, and 0.6%, respectively. Among the 201 cases with bilateral inclusion, 87.6% showed consistent canal configuration. Results of the first clear apparent position (FCAP) of the MB2 canals showed that 434, 44, and 3 teeth had FCAP at the upper, middle, and bottom one-third of the root, respectively. The FCAPs of the MB2 canal in the MFMs with types II, IV, and VI, as well as types III and V canals showed significant differences (p<0.05). The horizontal distance between the MB1 and MB2 canal orifices in the type II canals of MFMs was significantly lesser than those in the type IV canals of MFMs (p < 0.01). The longitudinal distance between the pulp chamber floor plane and MB2 canal orifice significantly correlated with age (p < 0.05).ConclusionsThe morphology of the mesiobuccal root canal in the MFMs is complex. Complete understanding of the anatomical morphology of the root canal combined with the CBCT and dental operating microscope is necessary for the accurate detection of the MB2 canal and consequently improved success rate of root canal treatment. Our study findings can help endodontists improve endodontic treatment outcomes.

A Cone-Beam Computed Tomographic Analysis of Mesiobuccal Root Canals of Maxillary First Molars.

The maxillary first molar is crucial for proper bite formation and jaw positioning in adulthood. The prevalence of dental caries in the study's sample population suggests it is a common candidate for endodontic therapy. Multiple studies have shown that the canal and root morphology of the maxillary first molar are abnormal. The distobuccal and palatal roots of 286 maxillary first molars were removed at the furcation. The mesiobuccal roots were then imaged using cone-beam computed tomography (CBCT) on all specimens. The specimens were analyzed in comparison with one another. The following factors were studied. The number and arrangement of canals, as described by Vertucci; the presence or absence of an isthmus, as described by Kim; the canal curvature angle, as measured by the Schneider method; characteristics such as calcified segments, lateral canals, and an apical delta.For the flow analysis, CBCT was utilized to examine the root channel architecture of 286 mesiobuccal (MB) permanent maxillary first molar. Type I canal arrangement was found in 51.6% of teeth, Type II in 33.3%, Type III in 4.6%, Type IV in 4.2%, Type V in 2.5%, and Type VII in 1.5%. Type I, II, III, and V isthmus were each present in 26%, 6.7%, 9.5%, and 10.2% of the samples, respectively. Teeth with MB1 canal angulations of 0-20 degrees, 21-40 degrees, and more than 40 degrees were found in 56, 188, and 41 teeth, respectively. From 0 to 20 degrees, 21 to 40 degrees, and more than 40 degrees, 15 teeth, 88 teeth, and 25 teeth, respectively, had angulations in their MB2 canals. Only 9.8% of the samples had lateral canals, while 16.1% had both accessory canals and apical deltas. There were 19 cases with calcified segments in the coronal third of the MB1 canal and 13 cases in the middle third. There were no calcifications at the distal end of the MB1 canal. Thirteen of the specimens showed calcification only in the most caudal third of the MB2 canal, whereas the middle and distal thirds were uncalcified. Utilizing a noninvasive approach, a CBCT scan has the capacity to provide valuable insights into the root canal configuration.

Concurrency of additional canals in mandibular incisors and second mesiobuccal canal in maxillary first molars: A cone-beam computed tomography investigation.

This study investigated the concurrency of additional canals in mandibular incisors and the second mesiobuccal canal in maxillary first molars among the Chinese population. In total, 8644 cone-beam computed tomography images from 8644 patients with bilateral mandibular incisors and maxillary first molars were examined. The data were analysed using Chi-square test, binary logistic regression analysis and receiver operating characteristic curve. Among the patients with additional canals in mandibular central and lateral incisors, 96.2% and 95.5% of them had second mesiobuccal canal in maxillary first molars, respectively. Additional canals of mandibular incisors and second mesiobuccal canal in maxillary first molars exhibited a concurrent relationship. The prevalence of second mesiobuccal canal in maxillary first molars increased with the number of mandibular incisors with additional canals. Moreover, when there was at least one mandibular incisor with additional canals, the presence of the second mesiobuccal canal in maxillary first molars could be highly expected.

CBCT analysis of the localization of pulpal canals in maxillary first molars

CBCT analysis of the localization of pulpal canals in maxillary first molars

Negotiability of mesiobuccal canals in maxillary first molars using different path file systems

Background: In endodontics, glide path creation has been extensively considered a mandatory clinical step to improve the safety and efficiency of rotary nickel–titanium instruments. The high anatomic variations in the mesiobuccal (MB) root of the maxillary molars are observed in the form of canal configuration, number, and position.The aim of this study was to evaluate the negotiability of MB canals in maxillary molars using different pathfiling systems (ProGlider, R-pilot, HyFlex electrical discharge machining [EDM], WaveOne Gold Glider, and C-Pilot).Materials and Methods: This in vitro study included 125 maxillary first molars with closed apex. Before preparation, all teeth were scanned by periapical radiograph for review of the presence of second MB (MB2) canals, without any resorption or calcification, and moderate curve of MB root canal. Subsequently, the access cavity was prepared with a Diamond Fissure Bur. Then, the samples were divided into five groups (ProGlider, R-pilot, HyFlex EDM, WaveOne Gold Glider, and C-Pilot). Certain relevant indices were recorded for analysis, such as the negotiability of the glide path file in the MB canals, file fracture rate, and negotiation speed. The level of significance P value was set at 0.05.Results: In this study, HyFlex EDM was the only path file that could not reach the full working length (WL) in some cases. The highest frequency of file fracture in the MB2 was observed with HyFlex EDM (24%); nevertheless, R-Pilot presented an intermediate fracture rate (16%), and both ProGlider and WaveOne Gold Glider were the safest files (4%) in this regard. However, there were no significant differences between the groups (P = 0.065). The lowest and the highest average time of reaching full WL was observed with WaveOne Gold Glider and HyFlex EDM; nonetheless, there was no significant difference between the four rotary groups. The average number of pecks in HyFlex EDM was significantly higher in comparison to those reported for WaveOne Gold Glider and ProGlider.Conclusion: Path files used for glide path preparation in the MB2 canals of maxillary molars should be flexible with low taper. The use of HyFlex EDM in the MB2 canals is not recommended due to its high taper.

Influence of age and experience with magnification on locating the second mesiobuccal canal in maxillary first molars: A preliminary study.

The aim was to evaluate the effectiveness of clinical methods in identifying the presence of second mesiobuccal canal in maxillary first molars. The influence of age and experience with microscopy was also assessed. Sixty six teeth were selected and the mesiobuccal canal was confirmed in all of the samples by Cone-Beam Computed Tomography. After endodontic cavity access, teeth were evaluated through direct visual; dental loupe and operating microscope. None of the methods was successful in finding the mesiobuccal canal in all samples. Professionals <40, the magnification did not influence the location. Professionals >40, the magnification significantly influenced the location. In the direct vision, professionals >40 years located fewer canals than those <40 years of age with experience. In conclusion, these preliminary findings showed that when the microscope was used, the professionals with experience, regardless of age, found a higher number of canals. The use of the microscope was significant for professionals >40 years.

Association between second mesiobuccal canal and apical periodontitis in retrospective cone-beam computed tomographic images.

This retrospective cone-beam computed tomography study aimed to investigate the possible associations of apical periodontitis (AP) with missed/unmissed second mesiobuccal (MB2) canals. MB2 canals and AP were investigated in 257 endodontically treated and 673 untreated maxillary molars, and the former were analyzed regarding missed/unmissed MB2 canals. The chi-squared test and odds ratio (OR) were used for statistics. The prevalence of MB2 canals in maxillary first molars was higher than that in second molars (p= 0.001). MB2 canals were 1.751 times more common in males than in females (OR: 1.751; 95% CI: 1.334-2.297), with a significant difference in the 18-39 age groups (p= 0.005). The risk for AP was 5.5 times greater in endodontically treated maxillary molars with missed MB2 canals than in those with unmissed MB2 canals (p= 0.012) (OR: 5.5, 95% CI: 1.549-19.527). The findings of this study reveal that the likelihood of the MB2 canal is higher in the maxillary first molars of young adult males.

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.

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.

Dentine Thickness of Second Mesibuccal Canals in First Maxillary Molars Prepared with Rotary Instruments.

The purpose of this study was to evaluate the thickness of the remaining dentine wall in the danger zone of the second mesiobuccal (MB2) canals using cone-beam computed tomography (CBCT) in maxillary first molars following preparation by means of HERO 642 rotary instruments with different tapers. The study samples included twenty-five mesiobuccal roots of maxillary first molars. A two-step method was employed to prepare the MB2 canals applying HERO 642 instruments: using a 0.02 taper (step 1), and a 0.04 taper (step 2). The roots were scanned before preparation, and after each step. The thickness of the dentine wall was recorded at the CEJ level, as well as 2 mm and 4 mm below the CEJ. The repeated-measures ANOVA in conjunction with the Cochran tests were used to compare the changes in the thickness of the root canal wall. There was no area with dentine thickness of <0.5 mm before preparation. A significant reduction in dentine thickness occurred following the preparation with both 0.02 and 0.04 files at all three levels compared with the pre-instrumentation values (P< 0.05). However, areas with dentine thickness of < 0.5 mm after preparation using 0.04 files were significantly more than those resulting from the application of 0.02 files both at the CEJ and 2 mm-below-CEJ points, but the differences were not significant at the 4mm-below-CEJ level. Within the limitations of the present in vitro study, the use of larger taper instruments in MB2 root canals of maxillary first molars increased the quantity of samples with dentine thickness less than 0.5 millimeter at the coronal level of the root canal. It was concluded that instruments with large tapers, should be used with caution in troughing or preparing such root canals to reduce the risk of strip perforation.

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.

Prevalence of Untreated Mesio-Buccal 2 Canal in Maxillary First Molars Reported in KSA Since 2010: A Systematic Review

Several aspects are involved in the success of an endodontic therapy. Because root canal treatment is so complicated, it can't be evaluated using two-dimensional radiographs. Endodontic failure can occur if any section of the canal is overlooked and left untreated. The root canals of the first and second molars are the most complicated of all the maxillary teeth. Locating the mesio buccal (mb2) canal in the maxillary teeth for endodontic treatment is difficult. The mb2 canals are located utilizing three-dimensional technology and cone beam computed tomography (CBCT). The primary goal of this research is to conduct a systematic evaluation of publications that have reported on the occurrence of mb2 canal in maxillary first molars. Many studies in Saudi Arabia have found that the incidence of mb2 in maxillary first molars ranges from 23.3 percent to 70.6 percent, and that the incidence in maxillary second molars is about 19.8%. A few studies also found that direct viewing of the root, followed by troughing, was used to find an mb2 canal that was not visible on a CBCT scan.

Comparative evaluation of the efficiency of cone-beam computed tomography, clinical analysis, and dental loupes in detecting the MB2 canal in maxillary first molars. An in-vitro study

The success of an Endodontic treatment relies on the position and morphology of root canals. It is important for a clinician to be familiar with the canal morphology to negotiate and thereby filling the canals with an inert material. But, the possibility of negotiating the canals with the use of conventional technique alone is difficult. Hence, careful examination with the use of advanced techniques to enhance vision is required to minimize the rate of treatment failures. To compare the efficiency of three methods Cone-Beam computed Tomography (CBCT), clinical analysis, AND Dental Loupes in detecting the MB2 canal in maxillary first molars.One hundred and fifty extracted intact permanent molars were collected. Two examiners i.e., one Endodontist and a Radiologist examined CBCT images of teeth for the number and position of root canals. The first stage included unaided examination using an explorer and K- files. While those teeth that were failed to locate the canals were examined using dental loupes for better magnification. The results were analyzed by McNemar's tests with Bonferroni correction, and Chi-square test using SPSS software v21.Among 150 extracted teeth that were compared,MB2 was detected using CBCT in around 68% of the teeth, while with the use of naked eye and dental loupes, it was found to be around 30% and 66% respectively and the difference in the detection rates was statistically significant.With the view of the parameter under consideration, CBCT has high detection rates followed by dental loupes and naked eye vision. The efficiency of CBCT scans and dental loupes in detecting a second mesio-buccal canal, thus making it more likely to be treated by the clinician.

Occurrence and Morphology of MB2 Canals in Maxillary First Molars in an Indian Subpopulation: A Cone Beam Computed Tomography Study

AbstractIntroduction Molars have been known to display varied morphologies. Maxillary first molar is the tooth with the largest volume and most complex root and root canal anatomy; also, possibly the most treated and least understood posterior tooth. The present study aimed to investigate the occurrence and morphology of MB2 canals in maxillary first molars in an Indian subpopulation (Dakshina kannada) using cone beam CT (CBCT) imaging.Materials and Methods A total of 330 maxillary molars were placed on “U-” shaped modelling wax template, mimicking the natural arch and digitally scanned, of which 196 scans met the inclusion criteria and were analyzed for unusual root canal anatomy by CBCT. To analyze the occurrence and morphology of the canals, the acquired data was examined by two endodontists and discussed till an agreement was reached.Results The results were subjected to descriptive analysis. The majority of patients 103 (52.6%) teeth showed the presence of MB2 canals. As much as 83.5% of teeth depicted Vertucci's type II morphology, and 16.5% teeth presented with Vertucci's type IV morphology.Conclusion CBCT overcomes the limitations of conventional radiography. However, the decision to use CBCT in the management of endodontic problems must be based on a case-by-case basis and only when sufficient diagnostic information is not obtained from diagnostic tests.

Prevalence of Missed Canals and Their Association with Apical Periodontitis in Posterior Endodontically Treated Teeth: A CBCT Study.

Background This study aimed to assess the prevalence of missed canals in endodontically treated teeth and their association with apical periodontitis in a Saudi Arabian population using CBCT. Materials and Methods A total of 208 CBCT radiographs were investigated. For each tooth, radiographs of axial, coronal, and sagittal segments were acquired to appraise the external as well as the internal structure of the root canal system and apical area. In root canal-treated teeth, unfilled canals appearing from the cementoenamel junction to the apex were defined as missed untreated canals; and a periapical lesion was considered when disruption of the lamina dura was detected, and the low-density area associated with the radiographic apex was at least twice the width of the periodontal ligament space. The data were presented as frequencies and percentages. The Z-test was used to analyze the differences in proportions with the significance level set at P value <0.05. Results The overall prevalence of missed canals among endodontically treated teeth was 18%. The prevalence of missed canals was higher in maxillary first molars with 40.6%. The overall prevalence of apical periodontitis among teeth with missed canals was 90%. It was 84.2% in the maxilla and 100% in the mandible. The second mesiobuccal canal in the maxillary first molars and mesiobuccal and distobuccal canals in mandibular teeth were the most missed canals. Conclusion Apical periodontitis in root canal-treated teeth with missed canals was high (90%), with most identified missed canals in maxillary and mandibular first molars.

Prevalence of mesiobuccal 2 canal in first maxillary molar: A retrospective radiographic study

Finding two mesiobuccal root canals named MB1and MB2 in maxillary first molar is not uncommon. Mesio-buccal-2 (MB2) canal orifice located palatally to the mesio buccall orifice and buccally as well as mesially to palatal orifices. A complete understanding of MB2 root canal morphology can contribute to the successful outcome of root canal treatment. This study conducted on CBCT scans with age ranged from 15 to 60 years which was further divide into group I (15-30 years), group II (30-45 years) and group III (45-60 years). Unilateral as well as bilateral prevalence of MB2 canal in maxillary first molar in both the genders and prevalence of MB2 canal in maxillary first molar in accordance with age were determined. Results showed overall prevalence of MB2 canal in maxillary first molar was 60.7%. In age wise distribution, group II showed greater prevalence than group I and group III showed least prevalence than others. The results were statistically significant between age groups. There was no statistical significance obtained between gender and quadrant wise. Conventional diagnostic aids such as radiographs play an important role in assessment of complex root canal morphologies. These modalities, however, do not provide detailed information of the complexity as a result of their inherent limitations. Shifting from 2D radiographic techniques to 3D radiographic techniques provides better visualization and location of these small and difficult structures.

Assessment of the presence of a second mesiobuccal canal in maxillary first molars according to the location of the main mesiobuccal canal-a micro-computed tomographic study.

To investigate the root canal morphology of mesiobuccal (MB) roots in maxillary first molars, and to assess the presence of a second mesiobuccal canal (MB2) according to the location of the main MB canal. A total of 72 extracted permanent maxillary first molars were collected from dental clinics and were scanned with micro-CT and reconstructed three-dimensionally. The root canal systems were recorded according to Vertucci's classification, and the occurrence of accessory canals was also recorded. The root canal dimensions were measured at the coronal (furcation plane), middle, and apical root levels. The long (D) and short (d) diameters as well as the palatal (P) and buccal (B) distances from the center of the first mesiobuccal canal (MB1) to the root surface were measured, and the ratios of D/d and P/B were calculated. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic accuracy of using the ratio of P/B for predicting the presence of an MB2 canal. The best cut-off point was determined according to the sensitivity and specificity. The MB roots most frequently had a type 2-2 root canal with an incidence of 37.5% (27/72), followed by the type 1-1 (23.6%, 17/72) and type 2-1 (16.7%, 12/72) canal forms. Type 1-2 canals were detected only in 5 molars (6.9%), and type 2-1-2 canals were detected in 6 molars (8.3%). The other 5 cases included 1 case of type 1-2-1 canal and 4 cases of triple canals. MB2 canals were detected in 76.4% (55/72) of the total sample teeth. The incidence of accessory canals was 56.9% (41/72). The mean ratio of D/d was generally "greatest to least": coronal level > middle level > apical level for different root levels and MB single > MB1 > MB2 for different canals, which reflected a trend from a flat to a circular cross-sectional shape. ROC curve analysis showed that at the coronal and middle root levels, areas under the ROC curve (AUC) were greater than 0.99 (P < 0.01), and the best cut-off point was 1.58 and 1.55, respectively; at the apical level, the AUC was 0.94 (P < 0.01), and the best cut-off point was 1.77. The MB2 canals may be present in the MB roots of maxillary first molars with a high occurrence rate at various levels, and the P/B ratio of the MB1 is a good index for predicting the presence of an MB2. However, since all the sample teeth were collected from a Chinese population, clinicians have to be cautious while trying to apply the conclusions on teeth of other ethnic populations. By calculating the P/B ratio, an index reflecting the buccal deviation of the MB1, clinicians can predict the presence of an invisible MB2 in cone-beam computed tomography images with inadequate resolution.

Detecting second mesiobuccal canal in maxillary first molars in Erbil citizens: CBCT Retrospective study.

Background and Objectives: The success of root canal therapy is depending on cleaning and shaping of the root canals. The root canals have complex morphology and wide individual variations. The purpose of this study was to investigate the prevalence of second mesiobuccal canal (MB2) of maxillary first molars in Erbil population using cone beam computed tomography (CBCT). Materials and Methods: A total of 101 permanent maxillary first molars were randomly se-lected from Erbil citizens. All teeth were examined for the number of root canals and the pres-ence of second mesiobuccal canal by Cone Beam Computed Tomography (CBCT). Result: The MB2 canal was found in 80.2% (the 95% CI is 72.3% to 87.1%) of the analyzed cas-es (81/101). Conclusion: The second mesiobuccal canal was found in a high percentage of the samples. And it is within normal magnitude in comparison with the common findings in the literature. These results indicate that CBCT is an effective, high-precision diagnostic tool for detecting canals. Keywords: Maxillary first molars, second mesiobuccal canal, cone beam computed tomography, Erbil Citizens.

Clinical and Radiographic Examination Compared to Microscopic Examination in the Detection of Anatomical Features of Mesiobuccal Canals in Maxillary First Molars: A Diagnostic Study

Clinical and Radiographic Examination Compared to Microscopic Examination in the Detection of Anatomical Features of Mesiobuccal Canals in Maxillary First Molars: A Diagnostic Study