Failure Of Root Canal Treatment Research Articles

Comparison of the Time Required by Six Different Retreatment Techniques for Retrieval of Gutta-Percha: An In Vitro Study

Abstract Objective A retreatment is a conservative approach than periapical surgery in case of failed root canal treatment. Retreatment techniques that are efficient and faster should be the main concern to treat endodontic failure. This study aimed to compare the time required by various hand and rotary retreatment systems for the retrieval of gutta-percha (GP) from root canals. Materials and Methods A total of 120 extracted single-rooted premolar teeth with straight canals were chosen. Biomechanical preparation was completed using the Step-Back approach keeping the master apical file size 35. Then, teeth were down-packed and back-filled with System B device, along with AH Plus sealer. The teeth were categorized into six groups (n = 20) at random as per techniques applied for retrieval of GP: group I hand instrumentation (Hedstrom files and Gates-Glidden drills); group II ProTaper Universal Retreatment (PTUR) system; group III Mtwo Retreatment (Mtwo R) system; group IV D-RaCe; group V R-Endo; and group VI Mani Gutta Percha Remover (NRT-GPR). A chronometer was used to measure the time required for retrieval of GP. Data were examined by comparative evaluation of one-way analysis of variance and chi-square test. Results Among all the retreatment techniques used, D-RaCe was faster in GP retrieval than other groups. NRT-GPR system also took less time than other groups except for the D-RaCe system. The Mtwo R system was the slowest among all groups. Conclusion D-RaCe retreatment instruments required extensively less time for retrieval of GP than other groups (p < 0.001).

Aptamer decorated emodin nanoparticles-assisted delivery of dermcidin-derived peptide DCD-1L: Photoactive bio-theragnostic agent for Enterococcus faecalis biofilm destruction

BackgroundDespite the high success rate of root canal treatment, failures are observed in a broad range of cases. Therefore, the need for novel approaches with the development of new generations of antimicrobial agents and intracellular drug delivery systems as adjunctive therapy is undeniable. In this study, we investigated the antimicrobial effects of antimicrobial photodynamic therapy (aPDT) using dermcidin‑derived peptide DCD‑1L loaded onto aptamer-functionalized emodin nanoparticles (Apt@EmoNp-DCD-1L) against Enterococcus faecalis as one of the most common bacteria involved in recurrent root canal treatment failures. Materials and methodsFollowing preparation of EmoNp-DCD-1L, the binding of selected labeled Apt to EmoNp-DCD-1L was performed, followed by the specificity of Apt@EmoNp-DCD-1L to E. faecalis was determined. The antimicrobial potential of aPDT was then assessed after the determination of the minimum inhibitory concentration (MIC) of Apt@EmoNp-DCD-1L. The molecular docking analysis was conducted to evaluate the potential binding modes of EmoNp to the proteins involved in E. faecalis pathogenesis. Eventually, the anti-virulence capacity of Apt@EmoNp-DCD-1L-mediated aPDT was investigated via quantitative real-time PCR (qRT-PCR) assay following measurement of intracellular reactive oxygen species (ROS) generation. ResultsThe binding specificity of Apt@EmoNp-DCD-1L to E. faecalis was confirmed by flow cytometry. The results showed that the cell viability of E. faecalis exposed to aPDT groups employing the sub-MIC doses of Apt@EmoNp-DCD-1L (7.8 and 15.6 µM) was significantly reduced compared to the control group (P < 0.05). Also, Apt@EmoNp-DCD-1L in combination with a blue laser light was capable of enhancing the anti-biofilm activity of aPDT against E. faecalis biofilm. Data obtained from the qRT-PCR analysis showed significant downregulation in the expression level of genes involved in bacterial biofilm formation after exposure to aPDT (P < 0.05). Conclusions: This in vitro study highlights that aPDT with the minimum concentration of Apt@EmoNp-DCD-1L can be considered as a targeted bio-theragnostic agent for the detection and elimination of E. faecalis in the dispersed and biofilm states.

Impact of systemic health on treatment outcomes in endodontics.

The healing of periapical lesions after root canal treatment (RCT) is not the result of the curative action of the treatment. The process of healing begins with inflammation, and is resolved by the clearance of the immunogen that induces the immune response. Then, the periapical tissue itself carries out the healing of the periapical lesion, by repair or by a combination of repair and regeneration, depending on the host's reparative response working properly. The ultimate objective of RCT is to achieve wound healing by removing the source of bacterial antigens and toxins, allowing chronic inflammatory tissue to become reparative tissue. Some systemic conditions increase the susceptibility of the host to infection or impair the tissue reparative response, maintaining the inflammatory process and periapical bone resorption after RCT. This can cause the failure of RCT and even the need for extraction of the affected tooth. To analyse the scientific literature on the possible influence of systemic conditions on the treatment outcomes in endodontics, as well as to discuss the biological mechanisms that may be involved. The search was carried out in PubMed, SCOPUS and EMBASE. The inclusion criteria established were original scientific articles reporting data about some systemic condition in relation to treatment outcomes in endodontics, including clinical studies and studies carried out in animal models. Systemic factors (age, nutrition, stress, hormones, smoking habits), and systemic diseases, such as diabetes, cardiovascular diseases, osteoporosis, HIV infection, inflammatory bowel disease, and others, can influence or interfere in the repair of periapical tissues after RCT. Some of these systemic diseases can alter bone turnover and fibroblast function, preventing or delaying periapical wound healing. Others can alter the microvasculature, reducing nutrients and oxygen supply to periapical tissues. As a result, these systemic conditions can decrease the success rate of RCT and provoke incomplete wound healing (typically granulomatous tissue formation) in the periapical region. The results of this narrative review show worse success rate of RCT, with higher percentage of postoperative radiolucent periapical lesions and higher proportion of non-retained teeth (RFT), associated with several systemic conditions, such as smoking habits and diabetes.

Present status and future directions: Surgical endodontics.

Endodontic surgery encompasses several procedures for the treatment of teeth with a history of failed root canal treatment, such as root-end surgery, crown and root resections, surgical perforation repair and intentional replantation. Endodontic microsurgery is the evolution of the traditional apicoectomy techniques and incorporates high magnification, ultrasonic root-end preparation and root-end filling with biocompatible filling materials. Modern endodontic surgery uses the dental operating microscope, incorporates cone-beam computed tomography (CBCT) for preoperative diagnosis and treatment planning, and has adopted piezoelectric approaches to osteotomy and root manipulation. Crown and root resection techniques have benefitted from the same technological advances. This review focuses on the current state of root-end surgery by comparing the techniques and materials applied during endodontic microsurgery to the most widely used earlier methods and materials. The most recent additions to the clinical protocol and technical improvements are discussed, and an outlook on future directions is given. Whilst nonsurgical retreatment remains the first choice to address most cases with a history of endodontic failure, modern endodontic microsurgery has become a predictable and minimally invasive alternative for the retention of natural teeth.

Mobile Nanobots for Prevention of Root Canal Treatment Failure (Adv. Healthcare Mater. 14/2022)

Mobile Nanobots for Prevention of Root Canal Treatment Failure (Adv. Healthcare Mater. 14/2022)

The antibacterial efficacy of calcium hydroxide–iodophors and calcium hydroxide–barium sulfate root canal dressings on Enterococcus faecalis and Porphyromonas gingivalis in vitro

Background: A successful endodontic treatment is inseparable from the right choice of root canal dressing. The right choice of medicaments would result in patient satisfaction. Enterococcus faecalis (E. faecalis) and Porphyromonas gingivalis (P. gingivalis) are usually found in failed root canal treatments. Calcium hydroxide is a gold standard dressing that creates an alkaline environment in the root canal and has a bactericidal effect. Commercially, there are calcium hydroxide dressings with supporting additions, including calcium hydroxide–iodophors (CH–iodophors) and Calcium hydroxide–barium sulfate (CH–barium sulfate). Purpose: This study aimed to compare the antibacterial efficacy between CH–iodophors and CH–barium sulfate root canal dressings on E. faecalis and P. gingivalis. Methods: CH–iodophors and CH–barium sulfate were obtained commercially. E. faecalis and P. gingivalis were obtained from stock culture taken from the root canal of failed endodontic treatment. E. faecalis and P. gingivalis were cultured in Petri dishes, and for each bacterium, 12 wells were made in the media. Six wells were used for the CH–iodophors group, and six wells were used for the CH–barium sulfate group. CH–iodophors and CH–barium sulfate were deployed in the wells in E. faecalis and P. gingivalis cultured media in the Petri dishes. After incubation, the inhibition zone diameters were measured. An independent t-test was used for analysis, and the significance level was set at 5%. Results: There is a significant difference in the antibacterial efficacy of CH–iodophors and that of CH–barium sulfate on E. faecalis and P. gingivalis (p = 0.00001). Conclusion: CH–iodophors have a higher antibacterial efficacy than CH–barium sulfate on both E. faecalis and P. gingivalis.

Root canal morphology of mandibular premolars

The root canal system is complex and the canal may branch, divide and rejoin taking various pathways to the apex.One of the predominant causes of the failure of root canal treatment in mandibular premolars is due to the variations in root canal anatomy. The aim of this study was to survey the root canal morphology of mandibular first and second premolar teeth in a South Indian population using CBCT analysis.The sample included 150 CBCT images comprising mandibular first premolars and second premolars were collected from Saveetha Dental College and Hospitals.The study showed that Type 1(1-1) vertucci classification is seen in most of the mandibular first and second premolars.Within the limits of this study, Type I [1-1] Vertucci's classification is seen in most of the first premolar and second premolars.It can be concluded from the results of this study that mandibular first and second premolar teeth present a wide variety of radicular features, with one root and one canal being found in majority of cases.

Pattern of tooth extraction in a Tertiary Care Hospital-Karachi, Pakistan.

Objective: To identify the pattern of tooth extraction and its relative risk factors in our local population, in terms of gender distribution and age groups. Study Design: Cross-sectional study. Setting: Department of Oral &amp; Maxillofacial Surgery, Sir Syed College of Medical Sciences for Girls, Karachi-Pakistan. Period: May 2018 to April 2019. Material &amp; Methods: Following the selection criteria, a number of 242 patients were selected with the age ranging from 15 years to 65 years. After history and examination, following information was recorded in a proforma; age, gender, type of tooth extracted, reason for extraction of tooth (caries, periodontal disease, trauma, pericoronitis, impactions, prosthesis, supernumerary teeth and failed root canal treatment), relative risk factors (uncontrolled diabetes mellitus, smokers) were also noted, data was analyzed using SPSS version 21. Results: In 242 patients, 1149 underwent dental extractions in a period of 1 year. Mean age was 36 years with a male predilection. Most commonly extracted tooth was mandibular molar. Most common reason of tooth extraction were dental caries, followed by periodontal diseases. Relative risk factors like diabetes and smoking had a statistically strong association with tooth extraction. Conclusion: Dental extractions were more common in males. Most common reason of tooth extraction was dental caries. Diabetes and smoking are significant relative risk factor for extractions.

Nonsurgical Management of Periapical Lesions of Mandibular First Molar - Case Report

Periapical lesions develop from non-vital teeth. In teeth with non-hermetic root canal filling, the presence of microleakage bacteria will invade the root canal and reach the periradicular area and cause inflammation so that it develops into periapical lesions as a form of failure of root canal treatment. Periapical lesions should be treated with a non-surgical endodontic procedure with a fair success rate. The purpose of this case report was to evaluate conventional endodontics as non-surgical management of teeth with a periapical lesion in previously treated teeth.&#x0D; Case: A 25-year-old female patient came to a private practice with a complaint of cavity in her lower left molar. One month ago, she had a throbbing tooth pain for which she took analgesic medication. The tooth was treated by root canal treatment about 6 years ago. The patient had no history of systemic disease.&#x0D; Case Management: Occlusal Adjustment, non-vital root canal treatment, the core build-up (fibre reinforced composite) and full coverage direct composite restoration.&#x0D; Conclusion: Adequate root canal treatment affects the success of endodontic treatment, in this case, there was very good progress in healing of the periapical lesion.&#x0D; Periapical lesions develop from non-vital teeth. In teeth with non-hermetic root canal filling, the presence of microleakage bacteria will invade the root canal and reach the periradicular area and cause inflammation so that it develops into periapical lesions as a form of failure of root canal treatment. Periapical tissue develops in response to microbial assumption and their by-products that infiltrate the periradicular tissues and activate the host's immune reaction. A dynamic encounter between the host's immune response and microbial infective factors at the interface of the periodontal membrane and infected pulpal tissue results in various periapical lesions.[1,2,3]&#x0D; Periapical lesions should be treated with a non-surgical endodontic procedure with a fair success rate. Microbial elimination or minimization from the pulp system using efficient chemo mechanical preparation can lead to a successful treatment.[1,4,5] The aim of this case report is to evaluate conventional endodontics as non-surgical management of teeth with a periapical lesion.

Comparative Evaluation of Antibacterial Efficacy of Silver and Cadmium Nanoparticles and Calcium Hydroxide against Enterococcus faecalis Biofilm

The purpose of this study was to evaluate and compare the antibacterial efficacy of calcium hydroxide medicament, silver (AgNPs) and cadmium nanoparticles (CdSNPs) as medicament against the biofilms of Enterococcus faecalis on dentin sections. E. faecalis is commonly detected in asymptomatic and persistent endodontic infections. Twenty standard size dentin sections were prepared. E. faecalis was inoculated on these dentin sections for four weeks to form the bacterial biofilm. Twenty dentin sections were segregated into four different groups with five specimens in each group. Group I was kept as control group, and antibacterial efficacy was tested by treating biofilms with Ca(OH) 2 medicament, 0.02% AgNP and CdSNP gels for 7 days. The ultrastructure of biofilms from each group was examined under scanning electron microscope and was visually evaluated and compared for different groups. Ca(OH)2 exhibited a slight disruption of E. faecalis biofilm. Both AgNP and CdSNP medicaments disrupted E. faecalis biofilm effectively after 7 days of inoculation. AgNPs disrupted the biofilm more effectively than CdSNPs. Biofilms in control group, which was irrigated with saline, did not show any disruption of biofilm, which could be seen as homogenous layer over most of dentin sections. This study suggests that both AgNP and CdNP gels are effective against E. faecalis and can be used as a medicament to eliminate residual bacterial biofilms during root canal disinfection. AgNP medicament is more effective than CdNP, whereas Ca(OH) 2 is not effective against E. faecalis biofilms. Incomplete clearance and the development of antibiotic resistance in E. faecalis are the important factors for failure of root canal treatment. When cationic nanoparticles are introduced for the treatment of biofilms, it can interact with both extracellular polymeric substances and bacterial cells. The initial electrostatic attraction between positively charged nanoparticles and negatively charged bacterial surface leads to bacterial killing via the production of reactive oxygen species. Metal nanoparticles that are effective against E. faecalis have a significant potential role in the prevention and treatment of such cases, as bacteria do not develop resistance against metal nanoparticles.

Mobile Nanobots for Prevention of Root Canal Treatment Failure.

Millions of root canal treatments fail worldwide due to remnant bacteria deep in the dentinal tubules located within the dentine tissue of human teeth. The complex and narrow geometry of the tubules renders current techniques relying on passive diffusion of antibacterial agents ineffective. Here, the potential of actively maneuvered nanobots is investigated to disinfect dentinal tubules, which can be incorporated during a standard root canal procedure. It is demonstrated that magnetically driven nanobots can reach the depths of the tubules not possible with current clinical practices. Subtle alterations of the magnetic drive allow both deep implantations of the nanobots isotopically distributed throughout the dentine and spatially controlled recovery from selected regions, further supported by numerical simulations. Finally, the integration of bactericidal therapeutic modality with the nanobots is demonstrated, thereby validating the tremendous potential of nanobots in dentistry and nanomedicine in general.

A CLINICAL-RADIOGRAPHIC EVALUATION OF CROWN AND NON-METAL POST RESTORATION AFTER ROOT CANAL TREATMENT USING MODIFIED STRINDBERG CRITERIA IN ACADEMIC DENTAL HOSPITAL YOGYAKARTA

Background: Root canal treatment failure can be caused by periapical lesions and inadequate restorations such as post restorations. It showed that comprehensive evaluation, such as clinical or radiographic evaluation, is needed to observe the healing of endodontically treated dental and intra-radicular post-condition, especially fiber post and fiber reinforced composite (FRC). This research aims to evaluate the clinical and radiographic success of endodontically treated teeth restored with single crown restoration using a non-metal post. Methods: This study is a cross-sectional design and descriptive observation of evaluating endodontically treated teeth. 72 samples were collected from medical records, and radiographs of endodontically treated patients; then, scoring was carried out to categorize the treatment outcome using modified Strindberg criteria. Results: Endodontically treated dental restoration with non-metal post evaluation showed 63,9% teeth categorized as uncertain, followed by 36,1% teeth categorized as success and 0% in the failure category. Conclusion: The result of this study suggests that a longer follow-up period will be needed to achieve a more stable evaluation result.

Antibacterial effectiveness of moringa leaf (Moringa oleifera) nanoparticle paste with different concentration against Enterococcus faecalis

Background: Endodontic is a treatment that aims to eliminate bacteria from the root canal system. One of the bacteria that causes root canal treatment failure is Enterococcus faecalis. Chemomechanical preparation and root canal irrigation are not sufficient to eliminate bacteria completely, so root canal medication is necessary to make it more efficient. Moringa leaves contain tannins, flavonoids and saponins which have antibacterial properties. Objective: To determine whether moringa leaf nanoparticle paste had antibacterial effectiveness against the bacterium E.faecalis. Method: Experimental laboratory with posttest with control group design with Kirby-Bauer method. The sample consisted of moringa leaf nanoparticles with concentrations of 1% and 2.5%, calcium hydroxide and aquadest with each of them being repeated 3 times. The diameter of the inhibition zone was de-termined based on the inhibitory ability of the bacteria saturated on MHA agar media. Results: the result showed that the ave-rage diameter of the inhibition zone of moringa leaf nanoparticle paste with concentrations of 1% was 8.48 mm, 2.5% was 9.17 mm and calcium hydroxide was 10.2 mm. Data processing showed that the 2.5% moringa leaf nanoparticle paste group had the same antibacterial effect as the calcium hydroxide group. Conclusion: Moringa leaf nanoparticle paste (Moringa oleifera) with concentrations of 1% and 2.5% was quite effective in inhibiting the growth of E.faecalis.

Improving the microbial sampling and analysis of secondary infected root canals by passive ultrasonic irrigation

ObjectiveThe persistence of pathogenic microorganisms in root canals is the most common reason for the failure of root canal treatment and the necessity of a root filling treatment, which results in an uncertain prognosis due to technical complexity and the variety of highly adaptable microorganisms.This study evaluated the effect of passive ultrasonic irrigation (PUI) on the outcome of the microbial analysis of root canal-treated teeth with persistent or recurrent apical inflammation in vivo.Materials and methodsSample collection was performed after root filling removal (sample S1, control group) and after PUI with NaCl (sample S2) using sterile paper points. In total, 19 samples were obtained. Quantification was performed by means of serial dilution of the samples. Subcultivated pure cultures were identified using MALDI-TOF MS complemented by the Vitek-2-System or PCR, followed by sequencing of the 16S rRNA gene. The results of the samples (S1 and S2) were evaluated regarding their bacterial count and composition.ResultsThe total count of bacteria and the number of aerobic/facultative anaerobic microorganisms significantly increased in the S2-samples after application of PUI. The number of obligate anaerobic microorganisms showed an increase after PUI, although it was not significant. We detected 12 different aerobic/facultative anaerobic microorganisms before PUI, and in 21 cases after PUI. Two different obligate anaerobic microorganisms were found in S1 samples compared to nine different species in S2 samples.ConclusionsPUI is a powerful method for detaching bacteria in infected root canals and enables a more precise analysis of the etiology of persistent endodontic infections.Clinical relevanceThis study indicates that PUI exerts a positive cleansing effect and adds to the accessibility of microorganisms during the application of bactericidal rinsing solution in root canal treatments.

ROLE OF ENDODONTIC BIOFILM IN DENTISTRY

Endodontic infection is caused by microorganisms colonizing as surface aggregates in the root canal system. These complex microbial communities are called biofilms that harbours numerous microorganisms with altering ecological requirements and pathological potential. The root canal system's intricacy and unpredictability, along with the multispecies nature of biofilms, make disinfection extremely difficult. The primary goal of endodontic treatment is to eliminate the biofilm from the root canal walls which is responsible for endodontic infection.The most important factor for failure of root canal treatment is the persistence of microorganisms as bioflms in the root canals.Eradication of biofilm is made possible by specific instruments and disinfecting chemicals in the form of irrigants and/or intracanal medicaments.Endodontic research has focused on the characterization of root canal biofilms and the clinical methods to disrupt the biofilms along with microbial killing. The aim of this narrative is to review the mechanisms of biofilms' formation, their roles in pulpal and periapical pathosis, the different types of biofilms, the factors influencing biofilm formation, the mechanisms of their antimicrobial resistance, techniques to identify biofilms and the role of root canal disinfectants on biofilm removal.

Association between General Anesthesia and Root Canal Treatment Outcomes in Patients with Mental Disability: A Retrospective Cohort Study.

In the population of individuals with a disability, mental illness patients can be uncooperative during dental treatment; thus, general anesthesia has been widely applied during dental procedures. This study aims to investigate the association between general anesthesia and the outcomes of root canal treatment in patients with disability. Teeth treatment records of patients with disability from Kaohsiung Medical University Hospital Research Database and electronic database from January 2005 to December 2018 were used in this retrospective cohort study. The authors conducted analysis comparing root canal treatment outcomes under general anesthesia and non-general anesthesia, indicated by endodontic re-treatment or post-treatment teeth extraction. Over the 9-year follow-up period, root canal treatment outcomes representing a cumulative survival rate of 87.68% and 74.51% in the general anesthesia group and non-general anesthesia group, respectively, were found. After adjustment for potential confounders, the teeth with general anesthesia showed a substantially and significantly reduced HR of root canal treatment failure at 0.24 (95% confidence interval, 0.12 to 0.49). Our study supported the notion that root canal treatment with general anesthesia may entail substantial reduction of treatment failure in patients with disability.

Microflora Responsible for Failure of RCT : A Review

Endodontic treatment failure can be caused by a variety of factors, including bacterial persistence, improperly cleaned and obturated root canals, faulty coronal seal (leakage), and untreated canals (missed canals). The presence of bacteria such as Enterococcus (E.) faecalis inside the root canal system is the most common cause of endodontic failure. These bacteria are more resistant to disinfectants, resulting in an infection that persists intra-radicularly or extra-radicularly. Many other microorganism are also responsible for failure of root canal treatment, resulting in endodontic flare-up .&#x0D; This review article will discuss about the causes of failure of root canal treatment ,pathogenesis and strategies by which microbes persist in root canal, method of eradication of such microorganism and management of such cases.&#x0D; Keywords: Enterococcus, Enterococcus

Intentional Replantation – The novel technique for the management of separated instrument in apical third of tooth: A case report

Intentional replantation is a procedure in which an intentional tooth extraction is performed followed by reinsertion of the extracted tooth into its own alveolus. In this article, intentional replantation is described and discussed as a treatment approach for failed root canal treatment with broken instrument periapically in mandibular second molar.

Microbial Communities in the Extraradicular and Intraradicular Infections Associated With Persistent Apical Periodontitis.

Microorganisms in the complex root canal system and the extraradicular regions, including the periapical lesions and extraradicular biofilm may cause root canal treatment failures. However, few studies described the difference between the intraradicular and extraradicular infections from the same tooth associated with persistent apical periodontitis. This study aimed to characterize the microbiome present in the root canal, extraradicular biofilm, and periapical lesions associated with persistent apical periodontitis. The microbial communities in the root canal, extraradicular biofilm, and periapical lesions were investigated by Illumina high-throughput sequencing using Illumina Hiseq 2500 platform. The dominant phyla in the extraradicular and intraradicular infections associated with persistent apical periodontitis were Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, and the genera Fusobacterium, Morganella, Porphyromonas, Streptococcus, and Bifidobacterium dominated across all samples. Although extraradicular infection sites showed higher OTU richness and β-diversity compared to intraradicular samples, the occurrence of sinus tract rather than the sampling sites demarcated the microbial communities in the infections associated with persistent apical periodontitis. PERMANOVA analysis confirmed that the samples with or without sinus tracts contained significantly different microbial communities. Porphyromonas, Eubacterium, Treponema, and Phocaeicola were found in significantly higher levels with sinus tracts, whilst Microbacterium and Enterococcus were more abundant in samples without sinus tracts. In conclusion, diverse bacteria were detected in both intraradicular and extraradicular infections associated with persistent apical periodontitis, which might be influenced by the occurrence of the sinus tract. The results may provide new insight into the pathogenesis of persistent apical periodontitis.

Evaluation of the relationship between buccolingual width of mesiobuccal root and root canal morphology of maxillary first molars by cone-beam computed tomography.

Background:One of the main reasons for the failure of root canal treatment is the incomplete knowledge of the root canal system. With respect to the complexity of maxillary molars root canal system, and the possibility of the relationship between the buccolingual width of the mesiobuccal root and root canal morphology in maxillary molars, the aim of this study is to determine this relationship with cone-beam computed tomography (CBCT).Materials and Methods:This in vitro study carried out on 311 CBCT scans. Maxillary first molars (n = 311) were evaluated in three sagittal, axial, and coronal planes. For each tooth the number of canals, presence of second mesiobuccal (MB2), buccolingual width of mesiobuccal root at the cementoenamel junction (CEJ), and mid-root level, and type of canals according to the Vertucci's classification were determined.Results:The results showed that 49.1% of first maxillary molars had 3 and 50.8% had four root canals. The most common canal type in the mesiobuccal root was Vertucci's Type I followed by Types II, IV, and V. The prevalence of MB2 in the Iranian subpopulation was 50.1%. In maxillary first molars with MB2, the buccolingual width of mesiobuccal root at the CEJ and mid-root level (P < 0.001) was significantly greater than the corresponding values in other one without MB2.Conclusion:The results showed that the buccolingual width of mesiobuccal root in maxillary first molars at the CEJ level and mid-root was correlated with the number of root canals.