Dental Root Canal Research Articles

Testing the Inhibitory Activity of Bajakah Tampala (Spatholobus littoralis Hassk) Wood Extract from South Kalimantan on the Growth of Pseudomonas aeruginosa Bacteria

Background: Dental root canal treatment aims to eliminate microorganisms that cause infection in the tooth root canal, one of which is Pseudomonas aeruginosa bacteria. Disinfection of dental root canals with 0.5% - 5.25% NaOCl irrigation solution is still constrained so it is necessary to look for alternatives. The bajakah tampala plant (Spatholubus littoralis Hassk) is known to contain antibacterial compounds, namely flavonoids, saponins, tannins, and polyphenols. Objective: To evaluate the inhibitory activity of bajakah tampala wood extract (Spatholobus littoralis Hassk) from South Kalimantan against the growth of Pseudomonas aeruginosa bacteria. Method: Post test-only with control group design. The test groups were 100%, 75%, 50% bajakah tampala wood extract solution and positive control 2.5% NaOCL solution. Extraction using maceration method. Bacterial growth inhibition was tested by well diffusion method. Inhibition zone was measured using a caliper. Results: The growth inhibition from the largest to the smallest was shown by 75%, 100% and 50% bajakah wood extracts with mean inhibition zone diameters of 5.05 mm, 3.84 mm and 2.02 mm respectively, meanwhile the positive control was 16.14 mm. One Way Anova test showed significant difference in inhibition (p<0.05) in all groups. Post hoc test showed no significant difference in the inhibition of 75% bajakah tampala wood extract with 100% extract. The inhibition of 100% and 75% extracts was significantly greater than 50% extract. The inhibition of NaOCL 2.5% was significantly greater than all groups of test extracts. Conclusion: Bajakah tampala wood extract has inhibitory activity against the growth of Pseudomonas aeruginosa bacteria.

Antibacterial Activity of Stingless Bee Propolis (Heterotrigona itama) Ethanol Extract on Dental Root Canal Bacteria Growth in Vitro

Introduction: Pulp and periapical tissue problems are 7th out of the top 10 diseases. Propolis from stingless bees is a natural substance that has been proven its efficacy in treating the diseases. Additionally, it is categorized safe for humans. This study aimed to determine the antibacterial activity of stingless bee propolis (Heterotrigona itama) ethanol extract on dental root canal bacterial growth in vitro. Method: This study was an experimental study with a posttest-only control group design and consisting of six treatment groups with concentrations of 3,000; 6,000; 12,000; and 24,000 ppm of stingless bee propolis, as well as a positive and negative control. Each treatment was repeated four times. Result: The result showed that there were no clear zones at concentrations of 24,000 ppm, but a clear zones appeared at concentrations of 3,000; 6,000; and 12,000 ppm. Stingless bee propolis ethanol extract is efficient against bacteria. At a concentration of 3,000 ppm, the inhibition zone's maximum circumference was visible.

Antibacterial and Antibiofilm Activity of Ethanol Extract of Batak Onion Bulbs (Allium chinense G.Don.) against Streptococcus mutans and Enterococcus faecalis.

Background: S.mutans is the main pathogen causing caries, while E.faecalis is the dominant microorganism in dental root canals. Batak onion is one of Indonesia's biological resources frequently used as condiments by Batak tribes and possesses antibacterial compounds such as alkaloids, saponins, and flavonoids. Aims: To analyze antibacterial activity test based on Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and antibiofilm from 70% ethanol extract of Batak onion bulbs against S.mutans and E.faecalis. Material and Methods: This type of research is a laboratory experiment with a post-test only control group design. Determination of MIC by Kirby Baurer disc diffusion method, determination of MBC by streaking method, and colony tests are calculated using colony counters, determination of antibiofilm by Static Microtiter Plate Assays method, and checking the optical density at around 600nm. Data analysis of MIC, MBC, and antibiofilm using Oneway Anova and Post Hoc LSD tests. Results: MIC on S.mutans and E.faecalis was at a concentration of 0.78% with an average of one of inhibition of 9.00 ± 0.43 mm and 8.06 ± 0.20 mm; no MBC was found because no group was able to reduce bacteria 98-98%, Batak onion bulb extract has antibiofilm ability starting at a concentration of 0.78% with the ability to reduce S.mutans bacteria by 84.55% and 85.73% on E.faecalis. Conclusion: 70% ethanol extract of Batak onion bulbs can inhibit bacterial growth and biofilm of S.mutans and E.faecalis. The recommended dose for antibacterial and antibiofilm is a 6.25-50% concentration.

Effectivity of Irrigation Solution from Stevia rebaudiana Bertoni Leaf Extract on the Growth of Enterococcus faecalis Bacteries

Disinfection of Enterococcus faecalis bacteria in dental root canal treatment using NaOCL 0.5-2.5% is still a challenge. There is still very little data on the effectvity of Stevia rebaudiana Bertoni leaf extract irrigation solution against the growth of Enterococcus faecalis. This study evaluated the effectiveness of Stevia rebaudiana Bertoni leaf extract irrigation solution against Enterococcus faecalis ATCC 29212 through MIC (Minimal Inhibitory Concentration) and MBC (Minimal Bactericide Concentration) values. A number of 100 µl of E. faecalis suspension was inoculated into 96 microtitration wells, each containing 100 µl of 100%, 50%, 25%, 12.5%, 6.25%, 3.125%, 1.56% of Stevia leaf extract irrigation solutions, positive (NaOCL 2.5%) and negative (distilled water) control. Incubation was carried out for 24 hours at 37°C then optical density was measured with a microplate reader at 600 nm. Five µl of 10-9 dilution of each group was dripped and spread onto nutrients agar plate. The number of Enterococcus faecalis colonies was counting manually. There was no significant difference in average colony count of Enterococcus faecalis between the 100% and 50% Stevia leaf extract irrigation solution groups and the positive control (p>0.05). However, the 25%, 12.5%, 6.25%, 3.125%, and 1.56% Stevia leaf extract irrigation solution groups showed significant differences (p<0.05). Stevia leaf extract irrigation solution suppressed growth at MIC 6.25% by turbidimetry and MIC 1.56% by total plate count method using nutrient agar and than killed Enterococcus faecalis at MBC 50%. The bactericidal ability of 100% and 50% Stevia leaf extract irrigation solution is equal to NaOCL 2.5%.

Comparison of the Antibacterial Effectiveness of Moringa Leaf Extract (Moringa oleifera) on the Growth of Enterococcus faecalis and Streptococcus mutans Bacteria in Vitro

Streptococcus mutans and Enterococcus faecalis are bacterial pathogens of dental caries and root canal treatment failure. The growth of bacteria that cause dental and oral disease can be inhibited by using antibacterials derived from plants that have antibacterial properties. The aim of the research was to compare the antibacterial effectiveness of Moringa oleifera leaf extract against the growth of Enterococcus faecalis and Streptococcus mutans bacteria in vitro. This type of research is a laboratory experiment with a post test only control group design. The research samples were pure cultures of Streptococcus mutans and Enterococcus faecalis. There were seven treatment groups, namely Moringa leaf extract concentrations of 50%, 25%, 12.5%, 6.25%, 3.125%, positive control chlorhexidine and negative control DMSO with four repetitions each. Testing the antibacterial effectiveness of Moringa leaf extract used the diffusion and dilution method, then the data was analyzed using one way ANOVA and post hoc LSD statistical tests. Based on the research results, it was stated that there was effective inhibitory and killing power of Moringa oleifera leaf extract on the growth of Enterococcus faecalis and Streptococcus mutans bacteria. From the research results, it can be concluded that Moringa oleifera leaf extract is more effective as an antibacterial against Streptoccus mutans compared to Enterococcus faecalis

Profiling Antibiotic Susceptibility among Distinct Enterococcus faecalis Isolates from Dental Root Canals.

Enterococcus faecalis, a leading multi-resistant nosocomial pathogen, is also the most frequently retrieved species from persistently infected dental root canals, suggesting that the oral cavity is a possible reservoir for resistant strains. However, antimicrobial susceptibility testing (AST) for oral enterococci remains scarce. Here, we examined the AST profiles of 37 E. faecalis strains, including thirty-four endodontic isolates, two vanA-type vancomycin-resistant isolates, and the reference strain ATCC-29212. Using Etest gradient strips and established EUCAST standards, we determined minimum inhibitory concentrations (MICs) for amoxicillin, vancomycin, clindamycin, tigecycline, linezolid, and daptomycin. Results revealed that most endodontic isolates were susceptible to amoxicillin and vancomycin, with varying levels of intrinsic resistance to clindamycin. Isolates exceeding the clindamycin MIC of the ATCC-29212 strain were further tested against last-resort antibiotics, with 7/27 exhibiting MICs matching the susceptibility breakpoint for tigecycline, and 1/27 reaching that of linezolid. Both vanA isolates confirmed vancomycin resistance and demonstrated resistance to tigecycline. In conclusion, while most endodontic isolates remained susceptible to first-line antibiotics, several displayed marked intrinsic clindamycin resistance, and MICs matched tigecycline's breakpoint. The discovery of tigecycline resistance in vanA isolates highlights the propensity of clinical clone clusters to acquire multidrug resistance. Our results emphasize the importance of implementing AST strategies in dental practices for continued resistance surveillance.

A case of pneumomediastinum after dental root canal treatment

We presented a rare case in which a 27-year-old female patient developed cervicofacial emphysema and pneumomediastinum following dental root canal treatment on her lower right second molar. She presented to the emergency department with facial and neck pain, difficulty in swallowing, and a feeling of tightness and pressure in the chest. Computed tomography revealed free air foci extending from the right mandibular region to the mediastinum. Pneumomediastinum related to dental root canal treatment was considered and the patient was admitted to the thoracic surgery department and oxygen therapy and prophylactic antibiotics were initiated. After 3 days of observation, the emphysema resolved, the symptoms disappeared, and the inflammatory markers remained within normal limits. The patient was discharged in stable condition.

Synthesis and analyses of injectable fluoridated-bioactive glass hydrogel for dental root canal sealing.

This study aimed to synthesize fluoride-doped bioactive glass (F-BG) based thermo-sensitive injectable hydrogel for endodontic applications. The structural and phase analyses were done with Fourier Transform Infrared spectroscopy and X-ray Diffraction, respectively. The setting time of prepared injectable was investigated at 21°C (in the presence and absence of an ultrasonic scalar) and at 37°C. Flowability was tested according to ISO-6876:2012 specifications, whereas injectability was checked by extrusion method using 21-, 22-, and 23-gauge needles. The in vitro bio-adhesion and push-out bond strength were studied on days 7 and 90 and compared with the commercially available TotalFill®. The ion release profile was analyzed for up to 30 days with Inductively Coupled Plasma Optical Emission Spectroscopy. The fluoride release analysis was conducted periodically for up to 21 days in deionized water and artificial saliva using an ion-selective electrode. The final setting time at 21°C, 21°C+ultrasonic scalar, and 37°C were 38.66±3.21, 29.12±1.23, and 32±3.46 min, respectively. The flowability was 25±3.94 mm, and the injectability coefficient was ≥70.3 for 22, 21, and 57% in a 23-gauge needle. Fluoride release in deionized water was found to be significantly higher than in artificial saliva and increased with time. A significant difference in bond strength was found between days 7 and 90, where the strength was increased, and a new apatite layer was formed on the tooth surface. A rapid release of calcium, phosphate, and silicon ions was seen initially, whereby the continuous release of these ions was observed for up to 30 days. The prepared F-BG injectable hydrogel has shown promising results and has the potential to be used as an endodontic sealer.

Photodynamic Suppression of Enterococcus Faecalis in Infected Root Canals with Indocyanine Green, TroloxTM and Near-Infrared Light.

Recently, our group showed that additional supplementation of Trolox™ (vitamin E analogue) can significantly enhance the antimicrobial photodynamic effect of the photosensitizer Indocyanine green (ICG). Up to now, the combined effect has not yet been investigated on Enterococcus faecalis in dental root canals. In the present in vitro study, eighty human root canals were inoculated with E. faecalis and subsequently subjected to antimicrobial Photodynamic Therapy (aPDT) using ICG (250, 500, 1000 µg/mL) and near-infrared laser light (NIR, 808 nm, 100 Jcm-2). Trolox™ at concentrations of 6 mM was additionally applied. As a positive control, irrigation with 3% NaOCl was used. After aPDT, root canals were manually enlarged and the collected dentin debris was subjected to microbial culture analysis. Bacterial invasion into the dentinal tubules was verified for a distance of 300 µm. aPDT caused significant suppression of E. faecalis up to a maximum of 2.9 log counts (ICG 250 µg/mL). Additional application of TroloxTM resulted in increased antibacterial activity for aPDT with ICG 500 µg/mL. The efficiency of aPDT was comparable to NaOCl-irrigation inside the dentinal tubules. In conclusion, ICG significantly suppressed E. faecalis. Additional application of TroloxTM showed only minor enhancement. Future studies should also address the effects of TroloxTM on other photodynamic systems.

Lipophosphonoxins-A Novel Group of Broad Spectrum Antibacterial Compounds.

Lipophosphonoxins (LPPOs) represent a new group of membrane-targeting antibiotics. Three generations of LPPOs have been described: First-generation LPPOs, second-generation LPPOs, and LEGO-LPPOs. All three generations have a similar mode of bactericidal action of targeting and disrupting the bacterial cytoplasmic membrane of prokaryotic cells, with limited effect on eukaryotic cells. First-generation LPPOs showed excellent bactericidal activity against Gram-positive species, including multiresistant strains. Second-generation LPPOs broaden the antibiotic effect also against Gram-negative bacteria. However, both first- and second-generation LPPOs lose their antibacterial activity in the presence of serum albumin. LEGO-LPPOs were found to be active against both Gram-positive and Gram-negative bacteria, have better selectivity as compared to first- and second-generation resistance to LEGO-LPPOs was also not observed, and are active even in the presence of serum albumin. Second-generation LPPOs have been studied as antimicrobial additives in bone cement and as nanofiber dressing components in the treatment of wound infections in mice. Second-generation LPPOs and LEGO-LPPOs were also tested to treat ex vivo simulated endodontic infections in dental root canals. The results of all these studies were encouraging and suggested further investigation of LPPOs in these indications. This paper aims to review and compile published data on LPPOs.

Dialister pneumosintes and aortic graft infection – a case report

BackgroundDialister pneumosintes is an anaerobic, Gram negative bacillus, found in the human oral cavity and associated with periodontitis. It has also been isolated from gastric mucosa and stool samples. Recent case reports implicate D. pneumosintes in local infection such as dental root canals, sinusitis, Lemierres syndrome and brain abscesses, as well as distal infections of the liver and lung through haematogenous spread.Case presentationWe present a novel case of aortic graft infection and aortoenteric fistula (AEF) in a 75 year old Caucasian male, associated with D. pneumosintes bacteraemia. Microbiological evaluation of septic emboli in the lower limbs revealed other gastrointestinal flora. This suggests either AEF leading to graft infection and subsequent distal emboli and bacteraemia, or a dental origin of infection which seeded to the graft, resulting in AEF and systemic infection. To our knowledge this is the first report of D. pneumosintes associated aortic graft infection. The patient underwent surgical explantation, oversew of the aorta and placement of extra-anatomical bypass graft in conjunction with antimicrobial therapy, making a good recovery with discharge home after a 35-day hospital admission.ConclusionWe report a case of Dialister pneumosintes bacteraemia associated with aortic graft infection. To our knowledge, vascular graft-associated infection with D. pneumosintes has not been reported before.

Antibacterial Activity of Durian Peel Ethanol Extract (Durio zibethinus Murr.) against Streptococcus mutans and Enterococcus faecalis

Dental caries and root canal infections are common dental and oral diseases due to the dominance of S.mutans and E.faecalis. Despite not having any economic value and becoming a waste, durian peel is claimed as an antibacterial. This study aims to analyze durian peel ethanol extract antibacterial activity against S.mutans and E.faecalis based on the inhibition zone diameter, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). This type of research is a laboratory experiment using Post-test Only Control Group Design. There were 7 concentrations of durian peel ethanol extract (50%, 25%, 12.5%, 6.25%, 3.125%, 1.56%, and 0.78%), both positive and negative control with three times repetitions. Moreover, the bacterial suspensions used were S.mutans ATCC 25175 and E.faecalis ATCC 29212. Data analysis used One Way Anova, while data that were not normally distributed used Kruskal-Wallis. Post Hoc analysis used LSD for normal data and Mann-Whitney for abnormal data. Durian peel ethanol extract shows the antibacterial activity of S.mutans with MIC at a concentration of 0.78%, while against E.faecalis is 12.5%. The higher the concentration, the larger the inhibition zone formed. The best-tested concentration of ethanol extract from durian peel is 6.25-50% to inhibit the growth of S. mutans and 50% for E.faecalis. Durian peel ethanol extract can prevent dental caries since it is antibacterial against S.mutans and E.faecalis.

Treatment strategies for orbital gas-producing necrotizing fasciitis secondary to odontogenic maxillary sinusitis: Technical notes

This paper presents treatment strategies for orbital necrotizing fasciitis (NF) in a case of a 33-year-old male diagnosed with orbital NF, which developed after dental root canal treatment. Although orbital NF is rare, it is rapidly progressive and can easily lead to the loss of tissue and visual function, sometimes to a life-threatening extent. Prompt and adequate treatment has been a challenge yet remains quite essential. In addition to the conventional approach to NF, such as immediate antibiotic administration and drainage, orbital NF patients like this case were often treated by incorporating additional steps, which include: 1) performing minimally invasive but adequate removal of necrotic tissue through intraoperative use of ultrasound equipment and postoperative use of proteolytic enzyme-containing ointment for chemical debridement; 2) managing intraorbital pressure by lateral cantholysis and orbital floor removal (decompression); and 3) maintaining the aerobic conditions of the wound after surgical drainage via orbital wall removal. Thus far, satisfactory results in patients with extensive NF of the orbit, including the presented case, were achieved with regards to preserving periorbital tissues, vision, and ocular motility through a multidisciplinary approach. These should be considered as optional means of preserving the orbital tissue and visual function.

Using Dental Pulp Cells Derived from Stem Cells to Promote Dentin and Pulp Tissue Regeneration in Severe Tooth Decay: A Translational Research Method

Severe tooth decay is considered to be one of the major threats to dental health, which usually leads to the loss of tooth structure and, thus, its functional impairment. Traditional methods of dental treatment, like extractions, root canals, and fillings, may further contribute to more complications and do not really replace natural characteristics of teeth. In view of providing a biological answer to this common problem, the present study explores the potential of DPCs produced from stem cells for the regeneration of dentin and pulp tissue. The aims of this study were to produce and isolate DPCs, produce appropriate scaffold materials, and evaluate their in vivo and in vitro regeneration capacities. As opposed to the in vivo studies, which evaluated integration and functionality of regenerated tissues in animal models, studies in vitro focused on cell viability, proliferation, and odontoblastic differentiation. It has succeeded in establishing effective scaffold environments that would help in regeneration of dental tissues and demonstrated the ability of DPCs to differentiate into odontoblast-like cells. Further, it has developed standardized techniques for isolating and culturing DPCs. The study also provides a comprehensive evaluation framework through histological and functional assessments and will therefore play an important role in progress of regenerative dentistry. The results indicated that DPCs had high in vitro proliferation and cell survival. Further, they showed prominent mineral deposition and expression of odontoblastic markers like DMP1 and DSPP. High integration scores and functional restoration comparable to natural dentin testified that the regenerated tissues integrated very well with native tooth structures in vivo. These results open the way for DPC-based treatments to achieve structurally and functionally sound dental tissue regeneration.

Biomimetic materials in pediatric dentistry: A review article

In today's era, the human race is blindly running behind aesthetically pleasing procedures for the sake of acceptance in society wherein they lose their authenticity. Similar is the case with dentistry in which the biggest contradiction of modern restorative dentistry is that many of such artful procedures require the removal of existing dental tissue before a final prosthesis can be placed. In order to save a tooth, existing dental archetypes demand that a portion of the target tooth must be defaced. Hence, we are forced to think that if the goal of modern dentistry is to save and salvage as much of a patient’s natural dentition as possible, how does it make sense to rely on procedures that require the sabotage of the very thing you are trying to save? That’s where biomimetic dentistry comes in. Upholding the natural teeth and dental conservancy at the heart is Biomimetic dentistry. This new approach is all about being on the lookout for the synthesis of modern dental technologies and low-impact tooth conservation. Instead of relying on dental replacements, biomimetic dentistry is about perpetuating as much of a natural tooth as possible. Instead of housing over dental blemishes, it is about repairing and restoring existing dental surfaces. Instead of relying on dental techniques that remove or destroy parts of an existing tooth, such as dental extractions, crowns, and root canals, biomimetic techniques strive to cut back on the removal of natural dental material. It’s all about safeguarding what's there as much as possible and making it stronger and more resilient. Thus, the purpose of this article is to review various methods that not only result in a tooth that is more natural, but also more aesthetic, stronger, and longer lasting.

Molekularno ispitivanje gena enterokoknog površinskog proteina (esp) Enterococcus faecalis izolovanog kod endodontskih pacijenata

Objective. Enterococci are generally considered transient components of oral bacteria that may be a reason for several oral and systemic infections, particularly those related to dental root canal infections. The current study aims to examine the occurrence of Enterococcus surface protein, esp in Enterococcus faecalis, which is isolated from infected root canals. Methods. Forty samples were collected from endodontic patients who attended the Conservative Treatment Department in the College of Dentistry/Mosul University/Dental Teaching Hospital. Materials and Methods: All samples were traditionally examined using HiCrom TM Enterococcus faecium Agar base medium and biochemical tests. 16srRNA sequencing was performed using the polymerase chain reaction technique to confirm their identity. Then, all Enterococcus faecalis isolates were examined for the existence of esp gene coding for enterococcal surface protein using PCR assay. Results. From 40 clinical samples obtained, 31 isolates were recognized as E. faecalis by traditional methods; unexpectedly, other non-enterococci genera were also grown on HiCromTM Enterococcus faecium Agar base medium. The PCR products for the sequence-specific primers obtained from the full-length of 16S rRNA gene sequence, which belongs to E. faecalis, and the PCR products for specific primer of esp genes created bands at the position of 138bp and 932 bp on the agarose gel, respectively. The gene correlating with the aggregation of this bacteria on the canal walls was detected in a high proportion (91%) of the isolates. Conclusions. PCR assay provides an accurate, rapid, and more sensitive detection of E. faecalis. A positive correlation between esp gene and enterococcal infections in root canals has been found.

Conservative preparation of curved root canals using novel nickel-titanium instruments: influence of operator experience

BackgroundNickel-titanium (NiTi) instrumentation systems allow predictable dental root canal treatment. Novel systems promoting conservative preparation are constantly introduced into the market. Therefore, this study aimed to explore how operator experience would influence the performance using a new system – Race Evo- in preparation of curved root canals. MethodsThree groups of participants, with no previous experience with Race Evo, were compared: Third-year dental students, general dental practitioners (GPs), and endodontists. Each participant was asked to prepare 3 simulated resin blocks. Preparation time, the occurrence of procedural errors, and canal deviation were measured. ResultsEndodontists prepared the canals with significantly fewer procedural errors (p = 0.027), and in less time than students (p < 0.001) and GPs (p = 0.019). However, there was no significant difference in performance between undergraduate students and GPs. In fact, endodontists and students alike prepared the canal with less deviation compared to GPs (p = 0.006 and p = 0.002). ConclusionProficiency in instrumenting curved canals with a new conservative NiTi system was not influenced by experience related to that of the general dental practitioner, but required more specialized experience in root canal treatment. Regardless of experience level, a learning period was still necessary.

Chemical Gastroenterocolitis After the Root Canal Therapy - A Case Report

A 46-year-old patient with history of treated previously for colitis, was reported with severe abdominal discomfort, pain or uneasiness in colon area after the dental re root canal therapy was initiated.His physician started treatment with Xifan (Rifaxin 200mg), Proflora (intense Probiotic high potency), Divigest ADS digestive enzymes, Gasdep (lactobacillus acidophilus) ever since the reroot canal therapy started two months ago. When he developed his abdominal pain rectal discomfort, he was prescribed mesalazine rectal suppositories for his colitis. He was advised further investigations to perform gastroscopy, colonoscopy, to check for any edematous mucosa, any polyps like change in the whole mucosa of the stomach, duodenum, first part of jejunum, distal ileum, complete colon and rectum. With the history from the dentist, Formacresol was given as the intra canal medication after removing the gutta-percha. And his previous endodontic sealer was endomethasone. The diagnosis would be complicated without any of to achieve in synopsis with use of any dental materials like Formacresol, Endomethasone. Intracanal medication was changed to calcium hydroxide paste, his colitis symptoms decreased, calcium hydroxide paste was continued as intracanal medicament during the retreatment. Keywords: Chemical Gastroenterocolitis, Gastroenteritis, Root canal therapy, RCT

AN ASSOCIATIVE CLASSIFICATION BASED APPROACH TOWARDS ANALYSIS OF DENTAL CARIES X-RAY IMAGES

The most common disease on the planet is dental caries, also known as cavities. Almost everyone has had this condition at some point in their lives. Early identication of dental caries can considerably reduce the risk of serious damage to teeth in people who have dental disease. As medical imaging becomes more efcient and faster to use, clinical applications are having a greater impact on patient care. Recently, there has been a lot of interest in machine learning approaches for categorizing and analyzing image data. In this study, we describe a new strategy for locating and identifying dental caries from X-ray photos as a dataset and using associative classication as a classication method. This technique incorporates both classication and correlation. The numerical discrimination approach is also used in the strategy. This is the rst study to employ association-based classications to determine dental cavities and root canal treatment positions. This method was tested on real data from hundreds of patients and found to be very good at nding unexpected damage to teeth.

Transition metals and Enterococcus faecalis: Homeostasis, virulence and perspectives.

Enterococcus faecalis, a Gram-positive bacterium, is known to be a key player in several chronic infections as well as nosocomial, heart valve, urinary tract, surgical wound, and dental root canal infections. The capability to sense different transition metal levels and tune its response accordingly endows it with the potential to thrive and cause infections in several host niches. Over the past decade, our knowledge of how transition metals play a critical role in maintaining homeostasis of E. faecalis has improved significantly. The aim of this review is to elucidate the roles of metals such as iron, manganese, zinc, and copper in the physiology, metabolism, and pathogenicity of E. faecalis. These essential micronutrients contribute to energy production, redox stress response, expression of virulence determinants, and cooperation in polymicrobial communities. The review also highlights metal homeostasis systems in E. faecalis, which respond to fluctuations in extracellular metal levels, and regulate the intracellular metal content. Regulation of intracellular metallome secures the tolerance of E. faecalis to oxidative stress and host-mediated metal sequestration strategies. Therapeutic interventions which deprive E. faecalis of its essential metal requirements or disrupt its homeostatic control have been proposed to combat E. faecalis infections.