Mitochondrial Function and Root-Filled Teeth – Detrimental and Unknown Interfaces in Systemic Immune Diseases

This study demonstrates that toxins from Root Canal teeth can have detrimental effects on mitochondrial function.

PMCID: PMC7360410  PMID: 32765044

Conclusions: Within the short exposure time of 24 hours, and at a dilution of 1:100, the Tox-sol caused a median decrease in ATP activity of ~15% in 50% of test subjects. A practical VSCI reliably showed the effects of toxic sulfur compounds on the RFT. The toxic degradation products of biogenic amines from RFT can thus serve as possible contributing factors in the development of mitochondriopathies. 

Impact of Endodontically Treated Teeth on Systemic Diseases

This study recorded the  correlation between root filled teeth and immunological disturbances among people with systemic disease. Authors posit that root canal treatments are triggering factors for immune diseases, and call for more awareness on the relationship between root canals and systemic disease.

ISSN: 2162-1122 

Results: It was found that 42.5% of the group with systemic diseases showed immunological disturbance as a result of root-filled teeth. Furthermore, the presence of AP was almost three times higher than in the control group (17.2% versus 5.9%, respectively). 

Conclusions:  In summary, the data demonstrates that local pathologies caused by endodontically treated teeth may increase immunological and systemic dysfunction.

[Coincidence of uveitis, dental pulpitis and gingivitis]

A case report from demonstrating that chewing on infected root canal teeth can cause pathogenic bacteria to be pumped into the bloodstream and lymphatics. Published in Hebrew.

PMID: 1563666

Abstract: The coincidence of uveitis, dental pulpitis and gingivitis is reported. The patients were 2 women, 21 and 50 years old, respectively, and a man aged 36. All were cured by systemic antibiotic treatment. As uveitis is often found in otherwise healthy patients with no apparent focus of infection, it has been suggested that such a focus might be of dental origin. In a tooth abscess the seat of infection in the bone tissue is subject to pressure and irritation from chewing. This can cause bacteria from infected root canals to be pumped into the blood stream and lymphatics. The causes we describe demonstrate the importance of systemic, wide-spectrum antibiotic treatment in such cases.

Bacterial Signatures in Thrombus Aspirates of Patients With Myocardial Infarction

By taking biopsies of the blood clots found in heart attack victims, this study found pathogenic bacteria which originated in the mouth. Infected teeth and infected root canal teeth showed the strongest associations. Study suggests that infections in the mouth may contribute to heart attacks. 

PMID: 23418311

Abstract: Infectious agents, especially bacteria and their components originating from the oral cavity or respiratory tract, have been suggested to contribute to inflammation in the coronary plaque, leading to rupture and the subsequent development of coronary thrombus. We aimed to measure bacterial DNA in thrombus aspirates of patients with ST-segment–elevation myocardial infarction and to check for a possible association between bacteria findings and oral pathology in the same cohort.

Conclusion: Dental infection and oral bacteria, especially viridans streptococci, may be associated with the development of acute coronary thrombosis.

Increased Root Canal Endotoxin Levels are Associated with Chronic Apical Periodontitis, Increased Oxidative and Nitrosative Stress, Major Depression, Severity of Depression, and a Lowered Quality of Life

This study links depression to the toxins emitted from infected/inflamed root canal systems. 

PMID: 28455694

Abstract: Evidence indicates that major depression is accompanied by increased translocation of gut commensal Gram-negative bacteria (leaky gut) and consequent activation of oxidative and nitrosative (O&NS) pathways. This present study examined the associations among chronic apical periodontitis (CAP), root canal endotoxin levels (lipopolysaccharides, LPS), O&NS pathways, depressive symptoms, and quality of life...

Conclusions:  Increased root canal LPS accompanying CAP may cause depression and a lowered quality of life...

Dental health and "leaky teeth" may be intimately linked to the etiology and course of depression, while significantly impacting quality of life.

The Relationship Between Self-Reported History of Endodontic Therapy and Coronary Heart Disease in the Atherosclerosis Risk in Communities Study

Study shows that people who reported having 2 or more root canal treatments were more likely to have coronary heart disease.

PMCID: PMC2735042 PMID: 19654253

Background:

Current Trends in Root Canal Irrigation

This review examines and compares the irrigants used in root canal treatments, shares pros and cons, and notes no irrigant has been discovered that can "totally eradicate germs." 

PMCID: PMC9184175 PMID: 35698671

Review: the use of sodium hypochlorite in endodontics — potential complications and their management

This review shares the potential complications of using bleach in endodontic (root canal) treatments.  The article reminds us that severe cases are rare, and offers advice on how to manage the hazards of using bleach as a root canal irrigant.

Published by: The British Dental Journal

Irrigation in endodontics

This article highlights the importance of irrigation in root canal treatment, the difficulty of safely and effectively irrigating the tips of teeth roots, and the advancements in tools that can help.

Published by: The British Dental Journal

Association between Systemic Diseases and Endodontic Outcome: A Systematic Review

This study suggests systemic disease is related to root-treated teeth.

PMID: 28190585

Conclusions: Although additional well-designed longitudinal clinical studies are needed, the results of this systematic review suggest that some systemic diseases may be correlated with endodontic outcomes. 

Comparative Longitudinal Study on the Impact Root Canal Treatment and Other Dental Services Have on Oral Health-related Quality of Life Using Self-reported Health Measures (Oral Health Impact Profile-14 and Global Health Measures)

This study suggests patients without root-treated teeth are healthier than those patients with root-treated teeth.

PMID: 31202516

Introduction: The literature assessing quality of life for subjects who have undergone root canal treatment (RCT) is scarce. The aim of this study was to compare the effect of RCT with other dental services (exodontia, restorative, prosthodontics, periodontics, and negative controls [preventative and scale and clean]) on oral health-related quality of life.

Conclusions: The RCT group presented with similar oral health-related quality of life when compared with the other individual treatment groups; however, they consistently reported poorer oral health outcomes when the negative controls were included.

Systemic diseases caused by oral infection

This study found anaerobic bacteria in all the tested root-treated teeth, and recognizes that dissemination of these microorganisms into the bloodstream is common.

PMCID: PMC88948 PMID: 11023956

Summary: Recently, it has been recognized that oral infection, especially periodontitis, may affect the course and pathogenesis of a number of systemic diseases, such as cardiovascular disease, bacterial pneumonia, diabetes mellitus, and low birth weight. The purpose of this review is to evaluate the current status of oral infections, especially periodontitis, as a causal factor for systemic diseases. Three mechanisms or pathways linking oral infections to secondary systemic effects have been proposed: (i) metastatic spread of infection from the oral cavity as a result of transient bacteremia, (ii) metastatic injury from the effects of circulating oral microbial toxins, and (iii) metastatic inflammation caused by immunological injury induced by oral microorganisms. Periodontitis as a major oral infection may affect the host's susceptibility to systemic disease in three ways: by shared risk factors; subgingival biofilms acting as reservoirs of gram-negative bacteria; and the periodontium acting as a reservoir of inflammatory mediators. Proposed evidence and mechanisms of the above odontogenic systemic diseases are given.

Diversity of endodontic microbiota revisited

This study found over 460 different types of bacteria in root-treated teeth.

PMID: 19828883

Abstract: Although fungi, archaea, and viruses contribute to the microbial diversity in endodontic infections, bacteria are the most common micro-organisms occurring in these infections. Datasets from culture and molecular studies, integrated here for the first time, showed that over 460 unique bacterial taxa belonging to 100 genera and 9 phyla have been identified in different types of endodontic infections. The phyla with the highest species richness were Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria. Diversity varies significantly according to the type of infection. Overall, more taxa have been disclosed by molecular studies than by culture. Many cultivable and as-yet-uncultivated phylotypes have emerged as candidate pathogens based on detection in several studies and/or high prevalence. Now that a comprehensive inventory of the endodontic microbial taxa has been established, future research should focus on the association with different disease conditions, functional roles in the community, and susceptibility to antimicrobial treatment procedures.

Bacteria and virulence factors in periapical lesions associated with teeth following primary and secondary root canal treatment

Study found that periapical lesions of teeth with 1º treatment & re-treatment had pathogens: Parvimonas, E.faecalis, F. nucleatum, and P. endodontalis

PMID: 33270246

Conclusion: Periapical lesions associated with teeth after primary root canal treatment and retreatment had similar polymicrobial composition. The levels of LPS and LTA in periapical lesions associated with teeth after primary root canal treatment and retreatment were similar, and both were associated with the same symptomatology.

Oxidized LDLs inhibit TLR-induced IL-10 production by monocytes: a new aspect of pathogen-accelerated atherosclerosis

Study suggests pathogens and toxins from infected teeth are major reason for chronic inflammation in all stages of atherosclerosis

PMCID: PMC3397235 PMID: 22556042

Abstract: It is widely accepted that oxidized low-density lipoproteins and local infections or endotoxins in circulation contribute to chronic inflammatory process at all stages of atherosclerosis. The hallmark cells of atherosclerotic lesions—monocytes and macrophages—are able to detect and integrate complex signals derived from lipoproteins and pathogens, and respond with a spectrum of immunoregulatory cytokines. In this study, we show strong inhibitory effect of oxLDLs on anti-inflammatory interleukin-10 production by monocytes responding to TLR2 and TLR4 ligands. In contrast, pro-inflammatory tumor necrosis factor secretion was even slightly increased, when stimulated with lipopolysaccharide from Porphyromonas gingivalis—an oral pathogen associated with atherosclerosis. The oxLDLs modulatory activity may be explained by altered recognition of pathogen-associated molecular patterns, which involves serum proteins, particularly vitronectin. We also suggest an interaction between vitronectin receptor, CD11b, and TLR2. The presented data support a novel pathway for pathogen-accelerated atherosclerosis, which relies on oxidized low-density lipoprotein-mediated modulation of anti-inflammatory response to TLR ligands.

Association between periodontal pathogens and risk of nonfatal myocardial infarction

Study recognizes periodontal pathogens are associated with an increased risk of myocardial infarction (heart attack).

PMID: 21375559

Background: The direct effect of periodontal pathogens on atherosclerotic plaque development has been suggested as a potential mechanism for the observed association between periodontal disease and coronary heart disease, but few studies have tested this theory.

Conclusion: The presence of periodontal pathogens, specifically Tf or Pi, and an increase in total burden of periodontal pathogenic species were both associated with increased odds of having MI. However, further studies are needed to better assess any causal relationship, as well as the biological mechanisms underlying this association.

Periodontal disease and coronary heart disease incidence: a systematic review and meta-analysis

Study recognizes periodontal disease as an independent risk factor for Coronary Heart Disease (CHD).

PMCID: PMC2596495 PMID: 18807098

Results: We identified seven articles of good or fair quality from seven cohorts. Several studies found periodontal disease to be independently associated with increased risk of CHD. Summary relative risk estimates for different categories of periodontal disease (including periodontitis, tooth loss, gingivitis, and bone loss) ranged from 1.24 (95% CI 1.01-1.51) to 1.34 (95% CI 1.10-1.63). Risk estimates were similar in subgroup analyses by gender, outcome, study quality, and method of periodontal disease assessment.

Conclusion: Periodontal disease is a risk factor or marker for CHD that is independent of traditional CHD risk factors, including socioeconomic status. Further research in this important area of public health is warranted.

Detection of diverse bacterial signatures in atherosclerotic lesions of patients with coronary heart disease

Study identified more than 50 species of oral pathogens in patients with heart disease.

PMID: 16490835

Conclusions: Detection of a broad variety of molecular signatures in all CHD specimens suggests that diverse bacterial colonization may be more important than a single pathogen. Our observation does not allow us to conclude that bacteria are the causative agent in the etiopathogenesis of CHD. However, bacterial agents could have secondarily colonized atheromatous lesions and could act as an additional factor accelerating disease progression.

Identification of periodontal pathogens in atheromatous plaques

Study shows that the DNA of oral pathogens typical of root-treated teeth and gum disease has consistently been identified in atherosclerotic plaque.

PMID: 11063387

Background: Recent studies suggest that chronic infections including those associated with periodontitis increase the risk for coronary vascular disease (CVD) and stroke. We hypothesize that oral microorganisms including periodontal bacterial pathogens enter the blood stream during transient bacteremias where they may play a role in the development and progression of atherosclerosis leading to CVD.

Conclusions: Periodontal pathogens are present in atherosclerotic plaques where, like other infectious microorganisms such as C. pneumoniae, they may play a role in the development and progression of atherosclerosis leading to coronary vascular disease and other clinical sequelae.

Quantitative Analysis of CCL5 and ep300 in Periapical Inflammatory Lesions

Study shows that RANTES/CCL5 (a biological inflammatory signal) levels are high in periapical lesions.

PMID: 31718213

Background: Recent studies suggest that chronic infections including those associated with periodontitis increase the risk for coronary vascular disease (CVD) and stroke. We hypothesize that oral microorganisms including periodontal bacterial pathogens enter the blood stream during transient bacteremias where they may play a role in the development and progression of atherosclerosis leading to CVD.

Conclusions: This study confirmed that expression of CCL5 and ep300 is relevant for the pathogenesis of periapical inflammatory lesions but cannot be used as a distinctive marker between these lesions. 

Periodontal bacteria and hypertension: the oral infections and vascular disease epidemiology study (INVEST)

Study shows a direct relationship between oral pathogens and hypertension.

PMCID: PMC3403746 PMID: 20453665

Objective: Chronic infections, including periodontal infections, may predispose to cardiovascular disease. We investigated the relationship between periodontal microbiota and hypertension.

Conclusion: Our data provide evidence of a direct relationship between the levels of subgingival periodontal bacteria and both SBP and DBP as well as hypertension prevalence.

Prevalence of apical periodontitis and quality of root canal fillings in population of Zagreb, Croatia: a cross-sectional study

Study shows high percentages of root-treated teeth continue to have apical periodontitis.

PMCID: PMC3243319 PMID: 22180266

Results: There were 75.9% of participants with endodontically treated teeth and 8.5% of all teeth were endodontically treated. Only 34.2% of endodontically treated roots had adequate root canal filling length, while 36.2% of root canal fillings had homogenous appearance. From the total number of teeth with intracanal post, 17.5% had no visible root canal filling. Using PAI 3 as a threshold value for apical periodontitis, periapical lesions were detected in 8.5% of teeth. Adequate quality of root canal fillings was associated with a lower prevalence of periapical lesions.

Conclusion: We found a large proportion of endodontically treated teeth with apical periodontitis and a correlation between the quality of endodontic filling and the prevalence of periapical lesions. This all suggests that it is necessary to improve the quality of endodontic treatment in order to reduce the incidence and prevalence of apical periodontitis.

The global prevalence of apical periodontitis: a systematic review and meta-analysis

Study recognizes 50% of adult population worldwide have at least 1 tooth w/ apical periodontitis (114 studies, 34,668 people) and suggests health policy reform around this 'hidden burden.'

PMID: 33378579

Background: Apical periodontitis (AP) frequently presents as a chronic asymptomatic disease. To arrive at a true diagnosis, in addition to the clinical examination, it is mandatory to undertake radiographic examinations such as periapical or panoramic radiographs, or cone-beam computed tomography (CBCT). Thus, the worldwide burden of AP is probably underestimated or unknown. Previous systematic reviews attempted to estimate the prevalence of AP, but none have investigated which factors may influence its prevalence worldwide.

Conclusions: Half of the adult population worldwide have at least one tooth with apical periodontitis. The prevalence of AP is greater in samples from the dental care services, but it is also high amongst community representative samples from the general population. The present findings should bring the attention of health policymakers, medical and dental communities to the hidden burden of endodontic disease in the population worldwide.

Diabetes mellitus and the healing of periapical lesions in root filled teeth: a systematic review and meta-analysis

Data suggests a strong connection between periapical radiolucency on root-filled teeth and diabetes.

PMID: 32654191

Aim: To systematically analyse the available clinical literature to evaluate the association between DM and the prevalence of radiolucent periapical lesions in root filled teeth. The review question was 'Is there a difference between the root canal treatment healing outcome (in terms of presence or absence of radiolucent periapical lesions) in diabetic and non-diabetic patients?'.

Conclusions and implications of key findings: The data suggest a strong connection between the presence of periapical radiolucency on root filled teeth amongst diabetics as determined by the pooled OR.

Diabetes mellitus and the healing of periapical lesions in root filled teeth: a systematic review and meta-analysis

Study found that patients with peri-apical infection had a 2.8x higher risk of coronary artery disease (CAD).

PMID: 24461397

Introduction: Studies have shown that periodontal disease is independently associated with coronary artery disease. However, this same association has not been demonstrated with chronic apical periodontitis. The goal of this study was to establish the relationship between chronic apical periodontitis and coronary artery disease.

Conclusions: In these study patients, chronic apical periodontitis was independently associated with coronary artery disease.

Prevalence of apical periodontitis in root filled teeth: findings from a nationwide survey in Finland

Study found apical periodontitis (infection) in 39% of patients with root treated teeth as compared to only 9% in those without (n=120635).

PMID: 26919266

Aim: To assess the prevalence of apical periodontitis in the Finnish population aged 30 years and older and relate it to the technical quality of root filling by the type of tooth.

Conclusions: AP occurred principally in subjects and teeth with root fillings. Inadequate root fillings doubled the risk of AP. An improvement in the technical quality of root canal treatment is essential.

Epidemiological evaluation of apical periodontitis prevalence in an urban Brazilian population

Study found infections on 16.7% of root treated teeth from a sample size of 15,724. 

PMID: 25760068

Abstract: The present study aimed to assess the prevalence of apical periodontitis (AP) in an urban Brazilian population according to gender, age group and tooth type. Data were collected from clinical files containing the medical and dental histories and periapical radiographs of 1,126 patients treated at the School of Dentistry at Universidade do Estado do Rio de Janeiro between March 2000 and December 2010. A total of 15,724 periapical radiographs were evaluated. All the radiographs were evaluated by two independent, previously calibrated endodontists (kappa = 0.88). Periapical areas on the radiographs were classified as N (normal) or AR (apical radiolucency). The frequency of AP and the 95% Confidence Interval (95%CI) were calculated according to gender, age group and tooth type. Differences between groups were calculated using the Z-test at a significance level of 5% (p < 0.05). AP was present in 7.87% of the samples, with 16.70% occurring on previously endodontically treated teeth and 44.65% occurring on teeth referred for endodontic treatment (TR-RCT). The frequency of AP was higher among females (64%) than among males (35%). The central and lateral maxillary incisors were the most frequently affected teeth. The frequency of AP was higher among individuals between 30 and 49 years of age. In this population, AP was more prevalent among females and among individuals between 30 and 49 years of age, and the central and lateral maxillary incisors were the most frequently affected teeth.

Association of Radiographically Diagnosed Apical Periodontitis and Cardiovascular Disease: A Hospital Records-based Study

Study shows that subjects with apical periodontitis (AP) are 5.3x more likely to have cardiovascular disease (CVD). AP was significantly associated with the number of root canal treatments. 

PMID: 27091354

Introduction: Numerous studies have demonstrated an association between oral health status and systemic diseases. However, reports examining apical periodontitis (AP) and cardiovascular disease (CVD) are few. This study investigates whether an association exists between AP and CVD.

Results: AP was significantly associated with CVD, hypercholesterolemia, race, missing teeth, caries experience, and number of root canal treatments in our bivariate analysis. Our final adjusted conditional logistic regression model showed statistically significant positive associations between AP and CVD (odds ratio, 5.3; 95% confidence interval, 1.5-18.4).

Conclusions: Subjects with AP were more likely to have CVD than subjects without AP by 5.3-fold. However, further research is needed to elucidate temporality and reinforce association between CVD and AP.

Apical periodontitis and incident cardiovascular events in the Baltimore Longitudinal Study of Ageing

Study identifies “endodontic burden” is an independent predictor of cardiovascular events. 

PMCID: PMC5134837 PMID: 26011008

Aim: To evaluate whether the presence of apical periodontitis (AP), root canal treatment (RCT) and endodontic burden (EB) - as the sum of AP and RCT sites - were associated with long-term risk of incident cardiovascular events (CVE), including cardiovascular-related mortality, using data on participants in the Baltimore Longitudinal Study of Ageing (BLSA).

Conclusions: EB in midlife was an independent predictor of CVE amongst community-dwelling participants in the BLSA. Prospective studies are required to evaluate cardiovascular risk reduction with the treatment of AP.

Association between chronic apical periodontitis and low-birth-weight preterm births

Study founds that prematurity and low birth weight associated with chronic apical periodontitis (CAP). Root treated teeth were not directly studied here, but other research has shown that root treated teeth are associated with CAP.

PMID: 25576210

Introduction: The objective of this study was to investigate the association between chronic apical periodontitis (CAP) and low-birth-weight preterm births (LBWPB).

Methods: Sixty-three women in postpartum period were included in this case-control study. The case group consisted of mothers of LBWPB infants (n = 33), and the control group was represented by mothers of newborns at term (n = 30). The CAP diagnosis was performed by using periapical radiographs through the periapical index in postpartum period. The χ(2) test, Fisher exact test, and linear and logistic regression were used for statistical analysis.

Conclusions: Prematurity and low birth weight were associated with radiographically detected CAP. Women with CAP in postpartum period had greater odds of LBWPB.

Glycated hemoglobin levels and prevalence of apical periodontitis in type 2 diabetic patients

Study found that periapical lesions are associated with hyperglycemia.

PMID: 25670246

Introduction: The purpose of this investigation was to study the possible association between the prevalence of apical periodontitis (AP) and the glycemic control of type 2 diabetic patients.

Methods: In a cross-sectional study, the radiographic records of 83 type 2 diabetic patients were examined. Glycemic control was assessed by the mean glycated hemoglobin (HbA1c level). AP was diagnosed as radiolucent periapical lesions (RPLs) using the periapical index score. The Student t test, chi-square test, and logistic regression analysis were used in the statistical analysis.

Conclusions: HbA1c levels of diabetic patients are associated with periapical status. Data reported in the present study, together with the results of previous studies, further support a relationship between glycemic control and periapical inflammation in diabetic patients.

Lipids and lipoproteins and inflammatory markers in patients with chronic apical periodontitis

Study found that periapical lesion size correlates with coronary heart disease CHD severity.

PMCID: PMC4678471 PMID: 26666260

Conclusion: We have found a positive correlation between apoAI level and the CAP lesion size and a negative correlation between LpPLA2 level and the CAP lesion size. The results suggest that apoAI and LpPLA2 in HDL particles have antiinflammatory action and together can limit the CAP lesion size in patient with a higher apoAI level. The literature data on the distribution of lipoprotein particles in subjects are still insufficient, so this problem requires further studies.

Bacterial invasion into dentinal tubules of human vital and nonvital teeth

Study found that vital teeth are much more resistant to bacterial invasion than non-vital teeth.

 PMID: 7714440 

Abstract: The difference in resistance to bacterial invasion into the dentinal tubules between vital and nonvital teeth has not been determined. This study was conducted to clarify the effect of vital pulp on bacterial invasion into the dentinal tubules. The specimens were 19 intact pairs of bilateral upper third molars of 19 healthy, young adult male volunteers. In each case, 30 or 150 days before extraction, pulpectomies and root canal fillings were carried out unilaterally and a class V cavity involving the dentin was made on the palatal surface of both the pulpectomized tooth and the nonpulpectomized opposite tooth. The cavities were left unprotected to expose them to oral flora until the extractions were done, and the extracted teeth were examined histologically. When extraction followed 150-day exposure to the oral flora, there was a statistically significant difference in the bacterial invasion rate between the vital and nonvital teeth. It was postulated that vital teeth were much more resistant to bacterial invasion into the dentinal tubules than were nonvital teeth, thereby suggesting that the vital pulp plays some important role in this process.

Dentinal tubule invasion and adherence by Enterococcus faecalis

Study found that E. faecalis (a species of bacteria) readily invades dentin tubules.

 PMID: 18822013 

Aim: To investigate dentinal tubule invasion and the predilection of Enterococcus faecalis for dentinal tubule walls.

 Conclusions: Although E. faecalis readily invaded tubules, it did not adhere preferentially to tubule walls. Initial colonization of dentinal tubules by E. faecalis may depend primarily on other factors.

Microbial invasion of dentinal tubules: a literature review and a new perspective

Study found that dentin tubules are favorable niches for microbial survival.

PMID: 25044266 

Abstract: Various features of endodontic microbiology have been investigated using various methods. The aim of the present study was to review the existing literature on endodontic microbiology in dentinal tubules, and to present the features of two cases with endodontic pathology. An electronic search was performed with a search string created ad hoc. Ex vivo and in vitro studies were included, recording the method of detection and characteristics of analyzed teeth. Twenty studies fulfilled the inclusion criteria. Seven of them were in vitro laboratory studies on teeth inoculated after extraction, while 13 were ex vivo studies on extracted, infected teeth. Endodontic bacteria were detected in dentinal tubules, both as single units and as biofilm aggregates. Two similar in vitro cases presented here corroborate the latter findings. A number of techniques have been utilized to observe bacteria in the dentinal tubule ecosystem. Dentinal tubules are favorable niches for microbial survival, either in the form of monomicrobial or polymicrobial communities.

A scanning electron microscopic evaluation of in vitro dentinal tubules penetration by selected anaerobic bacteria

Study found that all bacterial strains tested were able to penetrate dentin tubules.

PMID: 8934991 

Abstract: In vitro root canal dentinal tubule invasion by selected anaerobic bacteria commonly isolated from endodontic infections was evaluated. Dentinal cylinders obtained from bovine incisors were inoculated with bacteria, and microbial penetration into tubules was demonstrated by scanning electron microscopy. The results indicated that all bacterial strains tested were able to penetrate into dentinal tubules, but to different extents.

Diagnostic Accuracy of Cone-beam Computed Tomography and Conventional Radiography on Apical Periodontitis: A Systematic Review and Meta-analysis

Study found that diagnostic accuracy of apical periodontitis on 3D scans was 96% as compared with 72-73% on 2D imaging.

PMID: 26902914 

Introduction: Endodontic diagnosis depends on accurate radiographic examination. Assessment of the location and extent of apical periodontitis (AP) can influence treatment planning and subsequent treatment outcomes. Therefore, this systematic review and meta-analysis assessed the diagnostic accuracy of conventional radiography and cone-beam computed tomographic (CBCT) imaging on the discrimination of AP from no lesion.

Results: Only 9 studies met the inclusion criteria and were subjected to a qualitative analysis. A meta-analysis was conducted on 6 of these articles. All of these articles studied artificial AP with induced bone defects. The accuracy values (area under the curve) were 0.96 for CBCT imaging, 0.73 for conventional periapical radiography, and 0.72 for digital periapical radiography. No evidence was found for panoramic radiography.

Conclusions: Periapical radiographs (digital and conventional) reported good diagnostic accuracy on the discrimination of artificial AP from no lesions, whereas CBCT imaging showed excellent accuracy values.

Limited cone-beam CT and intraoral radiography for the diagnosis of periapical pathology

Study demonstrates how pathologies are often missed on 2D scans (70% of the time) and affirms 3D scans offer valuable diagnostic information.

PMID: 17178504 

Objective: To compare intraoral periapical radiography with 3D images for the diagnosis of periapical pathology.

Study design: Maxillary molars and premolars and mandibular molars with endodontic problems and examined with periapical radiographs and a 3D technique (3D Accuitomo) were retrospectively selected and evaluated by 3 oral radiologists. Numbers of roots and root canals, presence and location of periapical lesions, and their relation to neighboring structures were studied.

Results: Among 46 teeth, both techniques demonstrated lesions in 32 teeth, and an additional 10 teeth were found in the Accuitomo images. As regards individual roots, 53 lesions were found in both techniques, and 33 more roots were found to have lesions in Accuitomo images. Artefacts were sometimes a problem in Accuitomo images. In 32 of the 46 cases, all observers agreed that additional clinically relevant information was obtained with Accuitomo images.

Conclusions: A high-resolution 3D technique can be of value for diagnosis of periapical problems.

Periapical health related to the quality of root canal treatment in a Belgian population

Study on 4,617 teeth showed apical periodontitis on 40.4% of root-treated teeth.

PMID: 11307451 

Aim: The aim of this study was to collect data on the prevalence and technical standard of root canal treatment as well as the prevalence of apical periodontitis in Belgium.

Methodology: The panoramic radiographs of 206 Belgian adults attending the Dental School of the University Hospital of Gent were examined for endodontic treatment, periapical conditions and coronal restorations.

Results: Of the 4617 teeth examined, 6.8% were endodontically treated. Periapical radiolucencies were found in 6.6% of all teeth and in 40.4% of the endodontically treated teeth. More than half of the root-filled teeth (56.7%) were scored inadequate on the basis of a criterion evaluating the level of the root canal filling.

Conclusion: The endodontic treatment need of this Belgian subpopulation was great and the technical standard of root canal treatment disappointing. The findings indicate that there is still a substantial need for postgraduate endodontic education in Belgium and a need for specialists in endodontology.

Prevalence of apical periodontitis and root filled teeth in a Belgian subpopulation found on CBCT images

Study of more than 11k teeth in 804 patients evaluated by 3D scan, found apical periodontitis in 33% of the root-treated teeth.

PMID: 26992464 

Aim: To investigate the prevalence of apical periodontitis (AP) and root filled teeth found on cone-beam computed tomography (CBCT) scans in a Belgian subpopulation in a retrospective cross-sectional study.

Methodology: At the university hospital of Leuven, 804 patients received a CBCT scan between 01/01/2013 and 01/01/2014. The investigated sample included 631 scans with a permanent dentition and a total of 11 117 teeth. Prevalences and their confidence intervals are reported and the association between treatment, position of a tooth, gender and age with AP was determined using logistic regressions.

Results: A total of 656 teeth (5.9%) had signs of AP and 1357 teeth (12.2%) had been root filled. AP was present in 212 of the 9760 nonroot filled teeth (2.2%) and in 444 of the 1357 root filled teeth (32.7%). Adequate root fillings were detected in approximately half (49.3%) of the root filled teeth. The prevalence of AP was 22.8% when the root filling was adequate, when scored inadequate the prevalence increased to 41%. Univariate and multivariable logistic regression analyses revealed a significant relation of tooth position and treatment with AP. No difference in the prevalence of AP between male and female patients was detected.

Conclusion: The prevalence of AP was comparable with findings in other epidemiological studies. Root filled teeth had significantly more AP than nonroot filled teeth. The technical quality of the root fillings had a significant impact on the presence of AP. Therefore, emphasis on the quality of work and continuing education in the field of Endodontology must be provided in Belgium.

The post-endodontic periapical lesion: histologic and etiopathogenic aspects

Study suggests most root-treated teeth have variable degrees of apical periodontitis, and are completely asymptomatic.

PMID: 18059244 

Abstract: Apical periodontitis is produced in the majority of cases by intraradicular infection. Treatment consists in the elimination of the infectious agents by endodontia. Even when carrying out a correct cleansing and filling of canals, it is possible that periapical periodontitis will persist in the form of an asymptomatic radiolucency, giving rise to the post-endodontic periapical lesion. The chronic inflammatory periapical lesion is the most common pathology found in relation to alveolar bone of the jaw. From the histological point of view, it can be classified as chronic periapical periodontitis (periapical granuloma), radicular cyst, and as scar tissue. The most frequent is the periapical granuloma, constituted by a mass of chronic inflammatory tissue, in which isolated nests of epithelium can be found. The radicular cyst is characterized by the presence of a cavity, partially or wholly lined by epithelium. Scar tissue is a reparative response by the body, producing fibrous connective tissue. The aim of this study is to review and update the etiopathogenic and histological aspects of chronic post-endodontic periapical lesions.

Risk Factors for Apical Periodontitis Sub-Urban Adult Population

Study of 285 patients age 18-60 in Nigeria found 74% had apical periodontits (AP) (average 2.8 per patient); 87% of patients aged 40-49 had AP. Root fillings among the associated risk factors for AP.

PMID: 26259158 

Aims and objectives: To assess the risk factors of apical periodontitis (AP) in a Nigerian sub-urban adult population and to compare the findings with those previously reported for various population groups.

Materials and methods: The study was based on a full mouth radiographic survey of 285 patients. Patients' age ranged from 18-60 years. All teeth were assessed individually and data recorded for caries, fractured / cracked teeth, root fillings, and tooth restorations. The gender, smoking habit, and frequency of dental visit were also recorded. Multiple logistic regression analyses were performed to identify predictors of AP in the individual.

Results: The prevalence of AP was 74.4%. The average number of teeth with AP per patient was 2.8 (range 1-5). AP was found to be more prevalent among people 40- 49 years old (87.2%). Primary carious lesions, fractured / cracked teeth, root fillings and coronal fillings were associated with the incidence of AP in the individual. Fractured teeth had a higher risk of developing AP than carious teeth. The presence of root fillings and coronal restorations were also associated with the development of AP. Smoking (OR=3.82; CI=2.17-6.75) and irregular dental visit (OR=6.73; CI=3.75-12.06) were statistically significant risk factors for developing AP. Gender was not a risk factor for AP (OR=0.86; CI=0.50-1.46).

Conclusion: The prevalence of AP among adult Nigerians is slightly higher than reported figures for many Western societies. Fractured/cracked teeth had a higher risk of developing AP than carious teeth; hence patients with fractured / cracked teeth should seek treatment early to prevent the development of AP.

Prevalence of root canal treatment worldwide: A systematic review and meta‐analysis

This article simply shows how widespread and common root canal treatment is, with more than 50% of population studied having at least 1 root filled tooth.

PMCID: PMC9826350  PMID: 36016509

Background: 

The prevalence of root filled teeth (RFT) worldwide will inform about the amount of clinical activity of dentists dedicated to treat endodontic disease.

Results: Seventy‐four population‐based studies fulfilled the inclusion criteria. Twenty‐eight, forty‐four and two studies reported high, moderate and low risk of bias, respectively. No obvious publication bias was observed. Prevalence of RFT was estimated with 1 201 255 teeth and 32 162 patients. The calculated worldwide prevalence of RFT was 8.2% (95% CI = 7.3%–9.1%; p < .001). The global prevalence of people with at least one RFT was 55.7% (95% CI = 49.6%–61.8%; p < .001). In 20th century, the prevalence of RFT was 10.2% (95% CI = 7.9%–12.5%; p < .001), whereas in the 21st century the overall calculated prevalence of RFT was 7.5% (95% CI = 6.5%–8.6%; p < .001). Brazilian people (12%) and the European population (9.3%) showed the highest prevalence of RFT. In Europe, 59.6% (95% CI = 52.4%–66.8%) of people has at least one RFT.

Conclusions: This review showed that root canal treatment is a very common therapy throughout the world. More than half of the studied population have at least one RFT. A limitation of the present study is that most of the studies did not consider random sampling for population selection.

Root Canal Infection and Its Impact on the Oral Cavity Microenvironment in the Context of Immune System Disorders in Selected Diseases: A Narrative Review

This study demonstrates that toxins from Root Canal teeth can have detrimental effects on mitochondrial function.

PMCID: PMC10298853  PMID: 37373794