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

Current perspectives on calcium silicate-based intracanal medicaments: A scoping review of clinical and laboratory evidence

OBJECTIVE

Intracanal medicaments, primarily calcium hydroxide, play a significant role in optimizing root canal disinfection. Recently, calcium silicate-based intracanal medicaments have emerged as potential alternatives. This scoping review sought to map the available evidence concerning the clinical and laboratory properties of these bioceramic medicaments.

DATA

The study protocol was registered a priori (https://osf.io/rnyuv/) and a systematic search strategy using relevant MeSH terms was employed.

SOURCES

The search was conducted across databases including the Cochrane Library, EMBASE, PubMed/MEDLINE, SciVerse Scopus, and Web of Science.

STUDY SELECTION

Studies that investigated the clinical and laboratory properties of calcium silicate-based intracanal medicaments were included.

CONCLUSIONS

Out of 1008 potentially relevant articles, 15 met the inclusion criteria. The majority of the studies came from Brazil, primarily focusing on Bio-C Temp (Angelus). The studies revealed acceptable biocompatibility, alkaline pH, and high calcium ion release. However, they showed reduced antibacterial activity compared to conventional calcium hydroxide formulations. Tooth discoloration beyond clinically acceptable thresholds was also a significant concern. A single clinical case report exhibited potential for periapical healing and root development, though this evidence is very limited. While current evidence is preliminary, high-quality clinical trials are essential to determine their clinical efficacy and safety in endodontic treatments.

CLINICAL RELEVANCE

Calcium silicate-based intracanal medicaments have lower antibacterial activity and potential for tooth discoloration compared to conventional calcium hydroxide-based medicaments. Given the available evidence, they cannot be recommended for routine clinical practice.

Systemic Factors Affecting Prognosis and Outcome of Endodontic Therapy

The successful outcome of endodontic treatment is dependent on the immune response and the reparative potential of the individual. Alteration in the host immune response is a common characteristic shared by both apical periodontitis and systemic diseases. Although infection-induced periapical lesions occur in a localized environment, numerous epidemiologic studies in the last few decades have investigated the potential association between endodontic disease pathogenesis and systemic diseases. The goal of this review is to identify common systematic factors and discuss the effect they may or may not have on the prognosis and outcome of endodontic therapy.

Metformin reduced the alkaline resistance of Enterococcus faecalis against calcium hydroxide via Man-PTS EII: in vitro and in vivo studies

OBJECTIVES

The mannose phosphotransferase system (Man-PTS) plays crucial roles in the adaptive metabolic activity of Enterococcus faecalis (E. faecalis) in adverse environments. The aim of this study was to evaluate the role of Man-PTS in the alkaline resistance of E. faecalis against calcium hydroxide (CH) and the effect of metformin (Met) on the alkaline resistance of E. faecalis to CH.

MATERIALS AND METHODS

The regulatory role of Man-PTS EII in the alkaline resistance of E. faecalis was firstly investigated using a wild-type highly alkaline-resistant E. faecalis XS 003, standard ATCC 29212 and Man-PTS EIID gene deficient (△mptD) and overexpressing (+mptD)  strains of E. faecalis. RNA sequencing of Met-treated E. faecalis was performed to further validate the effect of Met on Man-PTS. The effect of Met on CH resistance of E. faecalis was verified by evaluating the survival, membrane potential and permeability, intracellular pH and ATP, and the expression of Man-PTS EII and membrane transporter-related genes of E. faecalis. The effect of Met on the ability of CH to remove E. faecalis biofilm on the dentin surface was also tested. The in vivo therapeutic effect of Met plus CH (CHM) was further investigated in a rat apical periodontitis model induced by E. faecalis XS 003.

RESULTS

Man-PTS EII significantly promoted the survival ability of E. faecalis in CH and enhanced its resistance to CH. The inhibition of Man-PTS EII by Met resulted in reduced alkaline resistance of E. faecalis in the presence of CH, while also enhancing the antimicrobial properties of CH against E. faecalis biofilm on dentin. Additionally, Met plus CH showed the synergistically promoted intra-canal E. faecalis infection control and healing of periapical lesion in rats.

CONCLUSIONS

Met could significantly reduce the alkaline resistance of E. faecalis against CH through the modulation of Man-PTS EII, and improved the antibacterial effect of CH against E. faecalis infection both in vitro and in vivo.

CLINICAL RELEVANCE

Met could significantly enhance the ability of CH to control E. faecalis infection through reducing the alkaline resistance of E. faecalis.

Assessment of Periodontitis Risk Factors in Endodontically Treated Teeth: A Cross-Sectional Study

The aim of the study was to collect data about the prevalence and risk factors of apical periodontitis in a population of endodontically treated patients. The study group included 151 patients (52 males, 99 females; mean age 48.36 ± 15.708 yrs.) with 391 endodontically treated teeth (mean follow-up of 5.25 ± 1.759 yrs.). According to the initial tooth diagnosis, root-filled teeth were divided into Group A, root-filled teeth treated for pulpitis or for the purpose of prosthetic pulpectomies (vital pulp group), and Group B, root-filled teeth with non-vital pulp (necrotic pulp). Clinical and radiographic evaluation of the root and its periapical area were performed to establish the success/failure of endodontic therapy, the quality of the root canal fillings (length, density, taper), and coronal restoration. The presence of recurrent caries, periodontal pathology, or endo-periodontal lesions were also recorded. Univariate and multivariate analyses were used to determine the risk factors for apical periodontitis and calculate their odds ratios (ORs). For the root-filled vital pulp tooth group, the highest risks for apical periodontitis are associated with inadequate homogeneity (OR 30.938), periodontitis (OR 9.226), and over-filling (OR 8.800). For the root-filled non-vital pulp tooth group, the highest risks are associated with periodontitis (OR 4.235) and age over 60 yrs. (OR 4.875). For the necrotic pulp tooth group, multivariate analysis identified an age > 60 yrs., filled molars, intracanal posts, poor coronal restoration quality, under-filling, and periodontitis as significant combined risk factors. Inadequate root canal filling and periodontitis in both groups were risk factors associated with most cases of apical periodontitis. Other risk factors include age > 60 yrs., poor coronal restoration quality, and the presence of intracanal posts in root-filled teeth with necrotic pulp.

Diagnostic accuracy of periapical radiography and panoramic radiography in the detection of apical periodontitis: a systematic review and meta-analysis

OBJECTIVE

Apical periodontitis (AP) is one of the most common pathologies of the oral cavity. An early and accurate diagnosis of AP lesions is crucial for proper management and planning of endodontic treatments. This study investigated the diagnostic accuracy of periapical radiography (PR) and panoramic radiography (PAN) in the detection of clinically/surgically/histopathologically confirmed AP lesions.

METHOD

A systematic literature review was conducted in accordance with the PRISMA guidelines. The search strategy was limited to English language articles via PubMed, Embase and Web of Science databases up to June 30, 2023. Such articles provided diagnostic accuracy values of PR and/or PAN in the detection of AP lesions or alternatively data needed to calculate them.

RESULTS

Twelve studies met inclusion criteria and were considered for the analysis. The average value of diagnostic accuracy in assessing AP lesions was 71% for PR and 66% for PAN. According to different accuracy for specific anatomical areas, it is recommended to use PR in the analysis of AP lesions located in the upper arch and lower incisor area, whereas lower premolar and molar areas may be investigated with the same accuracy with PR or PAN.

CONCLUSIONS

Two-dimensional imaging must be considered the first-level examination for the diagnosis of AP lesions. PR had an overall slightly higher diagnostic accuracy than PAN. Evidence from this review provided a useful tool to support radiologists and dentists in their decision-making when inflammatory periapical bone lesions are suspected to achieve the best clinical outcome for patients, improving the quality of clinical practice.

Osteoinductive and regenerative potential of premixed calcium-silicate bioceramic sealers on vascular wall mesenchymal stem cells

AIM

The osteogenic potential of new premixed calcium-silicate-containing bioceramic sealers (Ca-Si sealers) was tested with porcine vascular wall-mesenchymal stem cells (pVW-MSCs).

METHODOLOGY

Two Ca-Si-containing sealers: Ceraseal (MetaBiomed, Cheong-si, South Korea) and AH Plus Bioceramic (Maruchi, Wonju-si, South Korea), and an epoxy resin sealer (AH Plus; Dentsply, Konstanz, Germany) as a control, were prepared according to the manufacturers' indications. All samples were allowed to set for 100% of their setting time in a sterile humid cabinet at 37°C and 95% relative humidity. pVW-MSC seeding efficiency and osteogenic differentiation were analysed as marker of gene/protein expression for up to 12 days. Mineralization assay and immunofluorescence staining were performed and evaluated over a period of 21 days. Statistical analyses were conducted using one-way analysis of variance (p < .05). Additional samples were prepared and stored under the same conditions and inspected using an environmental scanning electron microscope equipped with an energy dispersive X-ray spectroscopy system.

RESULTS

Significantly higher cell seeding efficiency (p < .05) was observed for both Ca-Si sealers from day 8. pVW-MSCs showed a significant shift towards the osteogenic lineage only when seeded in contact with Ca-Si sealers. Gene expression of osteopontin was upregulated significantly. Collagen I and osteocalcin were clearly expressed by cells in contact with Ca-Si sealers. Mineralization granules were observed in Alizarin red assays and confocal laser scanning microscopy analysis of both Ca-Si sealers. No gene expression or granule mineralization were observed on the epoxy resin sealer.

CONCLUSIONS

Premixed Ca-Si sealers displayed a higher potential for osteogenic activity on pVW-MSCs. Epoxy resin sealer was unable to induce any osteogenic activity. The properties of both Ca-Si sealers suggest their potential as osteoinductive platforms for vascular MSCs in periapical bone.

Mitochondrial biogenesis disorder and oxidative damage promote refractory apical periodontitis in rat and human

AIM

To elucidate whether mitochondrial biogenesis disorder and damage from oxidative stress promote refractory apical periodontitis (RAP) in rat and human.

METHODOLOGY

Twenty Enterococcus faecalis-induced RAPs were established in the maxillary first molars of male Wistar rats. Concurrently, 12 periapical lesion specimens from patients presenting with RAP were obtained by apicoectomy. Radiographic examination and histologic analysis were conducted to evaluate periapical bone tissue destruction and morphological changes. The expression of key regulators of mitochondrial biogenesis, PGC-1α and Nrf2, were detected by immunohistochemistry and double immunofluorescence staining, Western blot and real-time PCR were also assayed. Mitochondrial ROS (mtROS) was identified by MitoSOX staining. Mitochondrial function was detected by the quantification of ATP production, mitochondrial DNA (mtDNA) copy number and activities of mitochondrial respiratory chain complexes. Furthermore, mitochondrial oxidative stress was evaluated by the determination of 3-nitrotyrosine (3-NT), 4-hydroxy-2-nonenal (4-HNE) and 8-hydroxy-deoxyguanosine (8-OHdG) expression levels, as well as malondialdehyde (MDA) expression and antioxidant capacity. Student's t-test was performed to determine significance between the groups; p < .05 was considered significant.

RESULTS

In the maxilla, significantly more bone resorption, greater number of periapical apoptotic cells and Tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells were observed in the RAP group compared with the control group (p < .01). PGC-1α and Nrf2 were significantly reduced in rat and human RAP lesions compared to the control group (p < .01) at both the mRNA and protein levels. Double immunofluorescence analysis of PGC-1α or Nrf2 with TOMM20 also indicated that mitochondrial biogenesis was impaired in RAP group (p < .01). Additionally, mitochondrial dysfunction was observed in RAP group, as reflected by increased mtROS, decreased ATP production, reduced mtDNA copy number and complexes of the mitochondrial respiratory chain. Finally, the expression levels of mitochondrial oxidative stress markers, 3-NT, 4-HNE and 8-OHdG, were significantly increased in the RAP group (p < .01). Consistent with this, systemic oxidative damage was also present in the progression of RAP, including increased MDA expression and decreased antioxidant activity (p < .01).

CONCLUSIONS

Mitochondrial biogenesis disorder and damage from oxidative stress contribute to the development of RAP.

The role of NF-kappaB in the inflammatory processes related to dental caries, pulpitis, apical periodontitis, and periodontitis-a narrative review

Tooth-related inflammatory disorders, including caries, pulpitis, apical periodontitis (AP), and periodontitis (PD), are primarily caused by resident oral microorganisms. Although these dental inflammatory conditions are typically not life-threatening, neglecting them can result in significant complications and greatly reduce an individual's quality of life. Nuclear factor κB (NF-κB), a family formed by various combinations of Rel proteins, is extensively involved in inflammatory diseases and even cancer. This study reviews recent data on NF-κB signaling and its role in dental pulp stem cells (DPSCs), dental pulp fibroblasts (DPFs), odontoblasts, human periodontal ligament cells (hPDLCs), and various experimental animal models. The findings indicate that NF-κB signaling is abnormally activated in caries, pulpitis, AP, and PD, leading to changes in related cellular differentiation. Under specific conditions, NF-κB signaling occasionally interacts with other signaling pathways, affecting inflammation, bone metabolism, and tissue regeneration processes. In summary, data collected over recent years confirm the central role of NF-κB in dental inflammatory diseases, potentially providing new insights for drug development targeting NF-κB signaling pathways in the treatment of these conditions. Keywords: NF-κB, dental caries, pulpitis, apical periodontitis, periodontitis.

Osteoporosis and Apical Periodontitis Prevalence: A Systematic Review

Osteoporosis is a common systemic bone disorder in the elderly, characterized by low bone mineral density and deterioration of bone structure. Apical periodontitis is an inflammatory response to the microbial infection of root canals, typically characterized by apical bone destruction surrounding the tooth's apex. This systematic review aimed to determine if osteoporosis affects the prevalence of apical periodontitis in adults. PRISMA guidelines have been followed. It included randomized clinical trials, cross-sectional, cohort, and case-control studies, and excluded non-relevant investigations and various secondary sources. A comprehensive search was performed in PubMed, Scopus, and Web of Science, until 13 March 2024. The Newcastle-Ottawa Scale was used to assess the quality of the three selected studies: two cross-sectional studies and one case-control study. One investigation only included post-menopausal women recruited at a dental university clinic, the other integrated data from the total hospital patients' population, and the third selected patients referred to the university dental clinic from the university hospital. The findings varied: one study noted a marginal association between low bone mineral density and apical periodontitis, another found a significant association, and the third, with the lowest risk of bias, reported no link. The main limitations were the scarcity of eligible studies and their overall quality. The review was registered in the PROSPERO database (CRD42024523705), applied strict inclusion criteria and thorough searches by experienced and independent reviewers. There is no strong evidence that adult individuals with osteoporosis have a higher probability of developing apical periodontitis. However, clinicians should remain cautious of osteoporosis's potential impact on apical periodontitis development.

Efficacy of the CALM® Algorithm in Reducing Motion-Induced Artifacts in CBCT Imaging: A Fractal Dimension Analysis of Trabecular Bone

OBJECTIVE

The primary goal of this investigation was to ascertain the efficacy of the CALM® motion artifact reduction algorithm in diminishing motion-induced blurriness in Cone Beam Computed Tomography [CBCT] images. The assessment was conducted through Fractal Dimension [FD] analysis of the trabecular bone.

METHODS AND MATERIALS

A desiccated human mandible was subjected to Planmeca ProMax 3D® scanning under eight distinct protocols, marked by variations in motion presence [at 5, 10, and 15 degrees] and the deployment of CALM®. In every scan, five distinct regions of interest [ROIs] were designated for FD analysis, meticulously avoiding tooth roots or cortical bone. The FD was computed employing the box-counting method with Image-J 1.53 software.

RESULTS

Our findings reveal that a 5-degree motion does not significantly disrupt FD analysis, while a 10-degree motion and beyond exhibit statistical differences and volatility among the sites and groups. A decreased FD value, signifying a less intricate or "rough" bone structure, correlated with amplified motion blurriness. The utilization of CALM® software seemed to counteract this effect in some instances, reconciling FD values to those akin to the control groups. Nonetheless, CALM®'s efficacy differed across sites and motion degrees. Interestingly, at one site, CALM® application in the absence of motion resulted in FD values considerably higher than all other groups.

CONCLUSION

The study indicates that motion, particularly at 10 degrees or more, can considerably impact the FD analysis of trabecular bone in CBCT images. In some situations, the CALM® motion artifact reduction algorithm can alleviate this impact, though its effectiveness fluctuates depending on the site and degree of motion. This underscores the necessity of factoring in motion and the employment of artifact reduction algorithms during the interpretation of FD analysis outcomes in CBCT imaging. More research is necessary to refine the application of such algorithms and to comprehend their influence on different sites under varying motion degrees.

Unilateral Sinus Disease: What Is, and Is Not Odontogenic Sinusitis?

The differential diagnosis of unilateral sinus disease (USD) is broad, and while concerning etiologies like sinonasal neoplasia, invasive fungal sinusitis, and cerebrospinal fluid rhinorrhea should always be considered, most cases are due to noninvasive inflammatory or infectious conditions. To diagnose USD appropriately, clinicians must integrate the clinical history and examination, nasal endoscopy, computed tomography (CT), and possibly MRI. Odontogenic sinusitis (ODS) is the most common cause of unilateral maxillary sinus opacification on CT, with 45% to 75% of such cases being odontogenic in nature. This study provides USD diagnostic considerations and reinforces the diagnostic approach to ODS.

Clinical Investigation of Bacteriome in Primary Endodontic Infections With Apical Periodontitis Using High-Throughput Sequencing Analysis

INTRODUCTION

This study characterized the bacteriome in primary endodontic infection (PEI) with apical periodontitis (AP), identified core and rare bacteriome species and community diversity metrics, and analyzed the relationship between the bacteriome composition, diversity and features, and patient variables.

METHODS

Twenty-seven patients with PEI and AP were sampled. The DNA was extracted and quantified using quantitative polymerase chain reaction. Raw V3-V4 amplicon sequencing data were processed with the DADA2 pipeline to generate amplicon sequence variants, and taxonomic assignment of the amplicon sequence variants up to the species level was done against the Human Oral Microbiome Database. Core bacteriome and differential abundance analyses were performed using ANCOM. Alpha diversity was determined using Chao1, Shannon, and Simpson indexes. LeFse analysis was used to identify abundant taxa. Sparse Estimation of Correlations among Microbiomes analysis estimated linear and nonlinear relationships among bacteria.

RESULTS

Of 27, 24 root canal samples were analyzed, and 3 root canal sampling were filtered out with a low read count. The bacterial phyla with top mean relative abundance were Bacteroidetes, Firmicutes, Synergistetes, Fusobacteria, and Actinobacteria. A total of 113 genera and 215 species were identified. The samples were gathered into 3 clusters. LefSe analysis identified differences in abundant taxa between distinct age, gender, symptomatology, and lesion size groups. Sparse Estimation of Correlations among Microbiomes distance analysis indicated Slackia exigua as the node with the highest degree.

CONCLUSIONS

The bacteriome in PEI with AP among the patients in this study was complex and displayed high microbial heterogeneity. Moreover, age, gender, symptomatology, and lesion size were associated with differences in bacteriome features in PEI with AP.

Twenty-first century knowledge mapping on oral diseases and physical activity/exercise, trends, gaps, and future perspectives: a bibliometric review

Maintenance and improvement of an individual's overall well-being require a multidisciplinary approach that encompasses everything from oral health care to regular physical exercise. The notion that poor oral health can influence general health and athletic performance has sparked an interest in this relationship. This study offers an overview of relevant research and a knowledge map,and discusses publication metrics and key topics concerning the relationship between physical activity or exercise and oral diseases. We searched the Web of Science database for articles published in the 21st century that addressed the relationship between physical activity and oral diseases. Under the stipulated inclusion criteria, a rigorous selection process yielded 276 from 3,883 retrieved articles. The articles were classified by what was assessed as follows: occurrence of oral diseases in athletes or sports enthusiasts (n = 174); impact of physical activity or exercise on the oral cavity (n = 59); effects of oral changes on sports performance and physical fitness (n = 31); and the connection between oral health status, physical activity or exercise, and systemic conditions (n = 12). Orofacial trauma has received the most attention among all investigated oral diseases. However, there is a need for greater attention of dysfunctional habits that can contribute to premature tooth wear, as well as oral inflammatory diseases that can have systemic implications. This mapping can encourage the development of new primary research.

A 980 nm Diode Laser as an Adjunctive Therapy on the Healing of Apical Periodontitis Following Endodontic Retreatment: A Randomized Controlled Clinical Trial Study

Introduction: Apical periodontitis is one of the common dental diseases. Microorganisms are the main reasons for these lesions; irrigations are used to remove them, but because of limited penetration, the rinsing agents may not always kill the microorganisms. Laser irradiation is effective in canal disinfection. The goal of this study was to compare the effect of calcium hydroxide (Ca(OH)2 ) and diode laser on the improvement of apical periodontitis following root canal retreatment (RCR). Methods: Twenty-four teeth of 19 patients with periapical lesions which needed RCR were divided into two groups (Ca(OH)2 and Ca(OH)2+laser irradiation [LI]). In the first session, after gutta-percha removal, cleaning, and shaping, Ca(OH)2 was used for 10 days. In the second session, in the Ca(OH)2+LI group, the irradiation utilizing a diode laser (using non-initiated 200-µm fiber, continuous wave (CW), power output of 1W) was done. The periapical radiographic healing was assessed before the retreatment and after 3-month and 6-month follow-ups by periapical index (PAI) Qrstavik. The quantitative data were analyzed (P<0.05). Results: The initial periapical lesion score was 3.75 and 3.88 in the Ca(OH)2 and Ca(OH)2+LI groups, respectively. In the Ca(OH)2 and Ca(OH)2+LI groups, 3 months after the RCR, the average periapical lesion score was 2.94 and 3.05, respectively. In the Ca(OH)2 and CA(OH)2+LI groups, 6 months after the RCR, the average periapical lesion score was 1.80 and 1.75, respectively. No significant differences were found at the 3 and 6 months between the experimental groups. Conclusion: The diode laser can reduce the periapical lesion, but there was no significant difference between CA(OH)2+LI and Ca(OH)2 at 3-month and 6-month follow-ups.

Guidelines for non-surgical root canal treatment

Guidelines were developed by the Australian Society of Endodontology Inc. with the intent to describe relevant aspects of contemporary evidence-based root canal treatment. The document aims to support clinicians by describing a Standard of Practice in the Australian context. The presented guidelines refer to Competence criteria and Quality standards for the main steps in root canal treatment. While the intent is not to replace individual clinical decision-making, it is envisaged that these periodically reviewable guidelines may help to improve clinical outcomes.

Triton X-100 enhanced antibacterial effect of photodynamic therapy against Enterococcus faecalis infection: an in vitro study

Photodynamic therapy (PDT) is an effective method for bacterial infection control in root canals of teeth with a broad-spectrum antibacterial activity. However, its application in root canal treatment is limited due to its inefficiency under hypoxic conditions and dentin staining. Triton X-100 (TX) shows great potential in enhancing the efficiency of antimicrobial agents through improving bacterial membrane permeability. The present study employed a combination of toluidine blue O (TB)-mediated PDT with TX to target the Enterococcus faecalis (E. faecalis), a bacterium with strong resistance to various antibacterial agents and mostly detected in infected root canals. PDT combined with TX showed enhanced antibacterial efficiency against both planktonic cells and biofilms of E. faecalis. At the same time, TX enhanced the antibacterial effect in dentinal tubules and reduced the incubation time. Mechanism studies revealed that TX improved reactive oxygen species (ROS) production through increasing the proportion of TB monomers. Additionally, increased membrane permeability and wettability were also observed. The findings demonstrated the PDT combined with TX could be used as a highly effective method for the root canal disinfection of teeth.

Short-term, nonsurgical periodontal therapy boosts interleukin-12 levels and reduces oral cancer risk

BACKGROUND

Cytokines, including interleukin-12 (IL-12), are proteins that regulate cell survival, proliferation, differentiation, and function. IL-12 is a heterodimeric proinflammatory cytokine. It possesses tumoricidal properties and promotes M1 macrophage polarization and IFN-γ production by T helper (Th1) cells, which in turn stimulates the antitumor cytotoxic cluster of eight positive (CD8+) and natural killer cells, therefore activating an effector immune response against tumor cells.

MATERIALS AND METHODS

Herein, the IL-2 levels of 60 patients with generalized chronic periodontitis (GCP) were assessed. Plaque index, gingival index, pocket probing depth, bleeding on probing percentage (BOP %), and clinical attachment loss were the clinical indicators reported.

RESULTS

Patients with GCP in the pretreatment group had substantially lower mean IL-12 levels than those in the post-treatment group. Short-term, nonsurgical treatment (NST) considerably improved periodontal indices and increased IL-12 levels, thereby reducing oral cancer risk.

CONCLUSION

NST is a cost-effective and accessible cancer prevention procedure for general dentists.

Prevalence of Apical Periodontitis in Saudi Arabia: A Systematic Review and Meta-analysis

Objective

This systematic review was aimed to assess the prevalence of apical periodontitis (AP) in Saudi Arabia, focusing on individual-level prevalence and the frequency of AP in endodontically versus untreated teeth.

Methods

This review followed the PRISMA guidelines and involved searches in several databases, including PubMed-MEDLINE, Cochrane-CENTRAL, and EMBASE, without date restrictions until August 19th, 2023. Eligibility criteria encompassed studies using CBCT, panoramic, and periapical radiographs to diagnose AP in the Saudi population. The meta-analysis employed a random-effects model due to high heterogeneity among studies.

Results

From 359 records, 13 studies were included, indicating a 40% prevalence of AP in individuals and a 6% prevalence across all teeth within the Saudi population. Root canal-treated teeth demonstrated a higher prevalence at 47%. The data revealed a substantial prevalence of AP compared to global averages, with first molars being the most affected. Studies showed moderate risk of bias and significant heterogeneity.

Conclusion

The high occurrence of AP in Saudi Arabia, particularly in root-treated teeth, emphasizes the need for enhanced endodontic care and more accurate diagnostics. Urgent improvements in dental health policies and further research are essential to understand AP's impact and improve oral health outcomes.

The immune landscape in apical periodontitis: From mechanism to therapy

Apical periodontitis (AP) is featured by a persistent inflammatory response and alveolar bone resorption initiated by microorganisms, posing risks to both dental and systemic health. Nonsurgical endodontic treatment is the recommended treatment plan for AP with a high success rate, but in some cases, periapical lesions may persist despite standard endodontic treatment. Better comprehension of the AP inflammatory microenvironment can help develop adjunct therapies to improve the outcome of endodontic treatment. This review presents an overview of the immune landscape in AP, elucidating how microbial invasion triggers host immune activation and shapes the inflammatory microenvironment, ultimately impacting bone homeostasis. The destructive effect of excessive immune activation on periapical tissues is emphasized. This review aimed to systematically discuss the immunological basis of AP, the inflammatory bone resorption and the immune cell network in AP, thereby providing insights into potential immunotherapeutic strategies such as targeted therapy, antioxidant therapy, adoptive cell therapy and cytokine therapy to mitigate AP-associated tissue destruction.

Effects of apical periodontitis treatment on hyperglycaemia in diabetes: A prospective cohort study

AIM

This prospective cohort study was undertaken to evaluate the success rate of root canal treatment (RCT) in type 2 diabetes mellitus (T2DM) patients with targeted level and unachieved targeted level of glycaemic control as well as the impact of RCT on the glucose blood level in T2DM patients.

METHODOLOGY

Patients needing RCT were divided into three groups: these without T2DM, that is, the control group (CG), those with targeted level of glycated haemoglobin HbA1c < 7% (TL A1c) and the third ones with unachieved targeted level (UTL A1c), that is, with HbA1c ≥ 7%. Before RCT, HbA1c and the periapical index (PAI) score were assessed, as well as 1 year later.

RESULTS

Our results showed less favourable treatment results of RCT such as a reduction of radiographic lesions in T2DM patients, particularly in subjects with UTL A1c. The intergroup analysis of PAI score at the 12-month follow-up revealed a significant difference in TL A1C (p = .022) and CG (p = .001) with respect to UTL A1c. Total number of healed teeth (PAI≤2) at the 12-month after RCT in UTL A1c was significantly lower in comparison to CG (p = .008). Contrariwise, RCT may improve the glycaemic control in diabetic patients with UTL A1c after 12 months of posttreatment. Regression analysis showed that UTL A1c patients were more likely to have AP persistence after endodontic treatment (OR = 4.788; CI: 1.157-19.816; p = .031).

CONCLUSIONS

T2DM retards the AP healing and conversely AP contributes to increasing the inflammatory burden in T2DM. RCT reduces the cumulative inflammatory burden in T2DM and thus may contribute to improvement of glycaemic control particularly in patients with UTL A1c.

COVID-19 Severity in Patients With Apical Periodontitis: A Case Control Study

OBJECTIVES

Apical periodontitis (AP) has been associated with systemic inflammatory biomarkers that have also been associated with COVID-19 severity. This study was designed to test the hypothesis that the presence of apical periodontitis could be associated with increased risk of COVID-19 complications.

METHODS

A case control study (N = 949) was performed using the medical and dental records of patients diagnosed with COVID-19 in the State of Qatar between March 2020 and February 2021. Cases comprised COVID-19 patients (n = 63) who experienced complications (death, intensive care unit admissions, mechanical ventilation), and controls were COVID-19 patients (n = 886) who recovered without such complications. The presence of periapical apical periodontitis was assessed on the radiographic records taken prior to COVID-19 infection. Associations between apical periodontitis and COVID 19 complications were analysed using logistic regression models adjusted for demographic and medical factors. Blood biomarkers were assessed in both groups and compared using the Kruskal-Wallis test.

RESULTS

COVID-19 complications were found to be associated with the presence of apical periodontitis (adjusted odds ratio = 2.72; 95% CI, 1.30-5.68; P = .008). Blood analyses revealed that COVID-19 patients with apical periodontitis had higher levels of white blood cells and haemoglobin A1c than the patients without apical periodontitis.

CONCLUSIONS

The presence of apical periodontitis could be associated with increased risk of COVID-19 complications.

Dental Pathophysiology of Odontogenic Sinusitis: Endodontic Infections

Bacterial odontogenic sinusitis (ODS) arises from maxillary dental issues or oral procedures, and affects at least the maxillary sinuses, with or without other paranasal sinus involvement. It has been historically underreported, in contrast to more recent findings attributing 25-40% of chronic maxillary sinusitis to dental causes. Endodontic infections represent one of the most common causes of ODS. Endodontic factors like root canal infection and microbial proximity to sinus cavities play pivotal roles. Host immunological responses further shape disease severity and progression. This article aims to explore the complexity of endodontic infections that cause ODS, elucidating anatomical, microbial, and immunological aspects.

Coronal and Root Canal Microbiota in Apical Periodontitis with Different PAI

Apical periodontitis is an inflammatory disease triggered by oral pathogens invading necrotic root canals. The aim of this study was to evaluate the coronal and root canal bacterial community profiles in primary endodontic infections with different periapical (PAI) indices in comparison to oral mucosa controls. A total of 31 patients with primary apical periodontitis, 14 with PAI-1 and 17 with PAI-3 were recruited. Microbial specimens from mucosa (control samples) and endodontic necrotic tissues were collected in each patient. Microbiota composition was studied through 16S ribosomal RNA gene amplicon sequencing analysis. Overall, 2953 taxa from 168 different genera of 451 various microbial species were retrieved in the controls and PAI-1 and PAI-3 groups. Firmicutes is the predominant phylum in the oral controls (34.5%) and PAI-1 (44.4%) groups, while Bacteroidetes is predominant in PAI-3 (38.6%). The Proteobacteria (21.5%) and Fusobacteria (12.5%) relative abundance is higher in oral controls while that of Synergistetes is higher in the PAI-1 (3.5%) and PAI-3 (2.5%) groups, being almost absent in controls (less than 0.1%). Most of the increased bacterial species found in the PAI groups were strict anaerobes. A diminished microbial diversity was found in apical periodontitis with higher PAI. These samples were also characterized by an increase in bacteria belonging to phyla and genera with an increased anaerobic character.

An in vitro study on the influence of laser-activated irrigation on infiltration and leakage of a dual curing-resin cement as an endodontic sealer

Objectives

The study aims to investigate the effects of laser-activated irrigation on infiltration and microleakage of a dual-curing resin cement applied as a root canal sealer.

Methods

Thirty-eight extracted upper molars were attributed to four experimental groups. Roots were mechanically enlarged and disinfected (NaOCl). Control samples (n = 11) were irrigated with conventional needles and three different lasers were used to activate the irrigant in the other groups (n = 9): 2.94 µm Er:YAG laser, 9,300 µm CO2 laser and 808 nm diode laser with a modified black coated laser tip. Final irrigation was performed in each group with ethylenediaminetetraacetic acid (EDTA), sodium hypochlorite (NaOCl) and sodium chloride (NaCl) activated with lasers and in the control without activation.Dentin tubules were then labeled with a red fluorophore (Rhodamine B) and the root canals were sealed with a dual-curing resin cement (Paracore). The cement fixed the dye on the sealed and infiltrated dentin parts. To remove the Rhodamine not fixed by the cement, roots were then sectioned horizontally and immersed in hydrogen peroxide (H2O2). The empty dentin tubules spaces were then labeled with a green fluorophore (Fluorescein) allowing the visualization of infiltration and microleakage by confocal microscopy.

Results

Percentages of infiltration were significantly higher in the middle root third of the control and Er:YAG laser-activated samples compared to CO2 or diode laser groups. Microleakage was present in all experimental groups but significantly less after CO2 laser activation.

Conclusion

Laser-activated irrigation impacted resin cement infiltration and microleakage dependent on the applied wavelength. Er:YAG laser activation led to higher values of infiltration and microleakage compared to CO2 and diode lasers.

Gut microbiota dysbiosis links chronic apical periodontitis to liver fibrosis in nonalcoholic fatty liver disease: Insights from a mouse model

AIM

In this study, we investigated the systemic implications of chronic apical periodontitis (CAP). CAP may contribute to the nonalcoholic fatty liver disease (NAFLD) progression through the gut microbiota and its metabolites, which are related to the degree of fibrosis.

METHODOLOGY

Sixteen 7-week-old male apolipoprotein E knockout (apoE-/-) mice were randomly divided into two groups: the CAP and Con groups. A CAP model was established by sealing the first- and second-maxillary molars with bacterium-containing cotton balls. Apical lesions were evaluated by micro-CT. Histological evaluations of NAFLD were performed using second harmonic generation/two-photon excitation fluorescence (SHG/TPEF) assays. Additionally, we comprehensively analyzed the gut microbiota using 16S rRNA gene sequencing and explored metabolic profiles by liquid chromatography-mass spectrometry (LC-MS). Immunofluorescence analysis was used to examine the impact of CAP on tight junction proteins and mucin expression. Transcriptome assays have elucidated gene expression alterations in liver tissues.

RESULTS

Micro-CT scans revealed an evident periapical bone loss in the CAP group, and the total collagen percentage was increased (Con, 0.0361 ± 0.00510%, CAP, 0.0589 ± 0.00731%, p < .05). 16S rRNA sequencing revealed reduced diversity and distinct taxonomic enrichment in the CAP group. Metabolomic assessments revealed that differentially enriched metabolites, including D-galactosamine, were enriched and that 16-hydroxyhexadecanoic acid and 3-methylindole were depleted in the CAP group. Immunofluorescence analyses revealed disruptions in tight junction proteins and mucin production, indicating intestinal barrier integrity disruption. Liver transcriptome analysis revealed upregulation of Lpin-1 expression in the CAP group.

CONCLUSION

This study provides comprehensive evidence of the systemic effects of CAP on liver fibrosis in NAFLD patients by elucidating alterations in the gut microbiota composition and metabolism.

Relationship of MMP-9 with the clinical course of apical periodontitis and the main bacterial species in the oral microbiota

Bacterial products, host immune cells and cytokines have been reported to play an important role in the pathogenesis of apical periodontitis (AP). This study aimed to determine the main bacterial species in the microbiota as gram positive and negative and to compare the relationship between matrix metalloproteinase (MMP)-9 and tumor necrosis factor (TNF)-α with controlled patient groups. 60 patients with AP and extraction indication were included in the study. 30 systemically healthy volunteers without AP were selected as the control group. After access cavity preparation, an initial microbiologic sample (S1) was taken from the root canal. After atraumatic extraction of the tooth, a second microbial sample (S2) was taken from the extraradicular region. After bacterial DNA extraction, 16S rRNA gene primer was designed for sequence analysis. Bacterial community profiling was made by Sanger sequencing of the PCR products. In addition, serum MMP-9 and TNF-α levels were measured from all patients. TNF-α levels of the AP group were higher than the control group, while MMP-9 levels were found to be lower (p = 0.0264 and p = 0.0146, respectively). There was no difference in the main bacterial species isolated from the samples taken from the intracanal and extraradicular region of the tooth with AP (p = 0.714). The main bacterial species in the intracanal region of the tooth with AP are similar to the main bacterial species in the extraradicular region. The pathophysiology of the tooth with AP is associated with low MMP-9 and high TNF-α, independent of the bacterial species in the intracanal and extraradicular regions.

The root canal microbiome diversity and function. A whole-metagenome shotgun analysis

AIM

To evaluate the root canal microbiome composition and bacterial functional capability in cases of primary and secondary apical periodontitis utilizing whole-metagenome shotgun sequencing.

METHODOLOGY

Twenty-two samples from patients with primary root canal infections, and 18 samples obtained from previously treated teeth currently diagnosed with apical periodontitis were analysed with whole-metagenome shotgun sequencing at a depth of 20 M reads. Taxonomic and functional gene annotations were made using MetaPhlAn3 and HUMAnN3 software. The Shannon and Chao1 indices were utilized to measure alpha diversity. Differences in community composition were evaluated utilizing analysis of similarity (ANOSIM) using Bray-Curtis dissimilarities. The Wilcoxon rank sum test was used to compare differences in taxa and functional genes.

RESULTS

Microbial community variations within a community were significantly lower in secondary relative to primary infections (alpha diversity p = .001). Community composition was significantly different in primary versus secondary infection (R = .11, p = .005). The predominant taxa observed among samples (>2.5%) were Pseudopropionibacterium propionicum, Prevotella oris, Eubacterium infirmum, Tannerella forsythia, Atopobium rimae, Peptostreptococcus stomatis, Bacteroidetes bacterium oral taxon 272, Parvimonas micra, Olsenella profusa, Streptococcus anginosus, Lactobacillus rhamnosus, Porphyromonas endodontalis, Pseudoramibacter alactolyticus, Fusobacterium nucleatum, Eubacterium brachy and Solobacterium moorei. The Wilcoxon rank test revealed no significant differences in relative abundances of functional genes in both groups. Genes with greater relative abundances (top 25) were associated with genetic, signalling and cellular processes including the iron and peptide/nickel transport system. Numerous genes encoding toxins were identified: exfoliative toxin, haemolysins, thiol-activated cytolysin, phospholipase C, cAMP factor, sialidase, and hyaluronic glucosaminidase.

CONCLUSIONS

Despite taxonomic differences between primary and secondary apical periodontitis, the functional capability of the microbiomes was similar.

The trend of radiographic healing after root canal treatment in teeth with apical periodontitis based on cone-beam computed tomography: A 4-year longitudinal study

OBJECTIVES

The aim of this study was to observe the radiographic healing of periapical lesions after root canal treatment via volumetric measurements based on cone-beam computed tomography (CBCT) over 4 years.

METHODS

In total, 162 single-root teeth from patients with chronic periapical periodontitis who underwent primary root canal treatment were included in this retrospective study. Follow-up visits were scheduled at 1, 2, and 4 years after treatment. The volume of radiolucency at pretreatment and follow-up were measured, and the radiographic outcomes were classified into 4 categories: absence, reduction, uncertain or enlargement. Reduction or enlargement was considered when the volumetric change in radiolucency was 20 % or more.

RESULTS

During the 4-year follow-up period, 128 teeth were reviewed at least once, including 3 extracted teeth. Of the remaining 125 teeth, the volume of radiolucency was reduced in 116 teeth (90.6 %), uncertain in 5, and enlarged in 4 teeth during 1 to 4 years after treatment. Among the 43 teeth with reduced radiolucency at 1 year after treatment, 42 (97.7 %) had continuing reduced lesions at 4 years. In the 2 teeth with enlarged radiolucency at 1 year, the volume of radiolucency doubled at 4 years. Cox regression analysis revealed that the preoperative radiolucency size was a risk factor for persistent periapical radiolucency.

CONCLUSIONS

The efficacy of root canal treatment for apical periodontitis was predictable. When the radiolucency changed by 20 % or more in volume on CBCT scans at 1 year after treatment, reversal of the radiographic healing tendency was rare.

CLINICAL SIGNIFICANCE

The volumetric changes in radiolucency on CBCT could reflect trends in the healing process and may foster early clinical decision-making.

Calcium hydroxide-loaded nanoparticles dispersed in thermosensitive gel as a novel intracanal medicament

AIM

Design, produce and assess the viability of a novel nanotechnological antibacterial thermo-sensible intracanal medicament This involves encapsulating calcium hydroxide (Ca(OH)2) within polylactic-co-glycolic acid (PLGA) nanoparticles (NPs) and dispersing them in a thermosensitive gel (Ca(OH)2-NPs-gel). In addition, perform in vitro and ex vivo assessments to evaluate tissue irritation and penetration capacity into dentinal tubules in comparison to free Ca(OH)2.

METHODOLOGY

Reproducibility of Ca(OH)₂-NPs was confirmed by obtaining the average size of the NPs, their polydispersity index, zeta potential and entrapment efficiency. Moreover, rheological studies of Ca(OH)2-NPs-gel were carried out with a rheometer, studying the oscillatory stress sweep, the mean viscosity value, frequency and temperature sweeps. Tolerance was assessed using the membrane of an embryonated chicken egg. In vitro Ca(OH)2 release was studied by direct dialysis in an aqueous media monitoring the amount of Ca(OH)2 released. Six extracted human teeth were used to study the depth of penetration of fluorescently labelled Ca(OH)2-NPs-gel into the dentinal tubules and significant differences against free Ca(OH)2 were calculated using one-way anova.

RESULTS

Ca(OH)2-NPs-gel demonstrated to be highly reproducible with an average size below 200 nm, a homogeneous NPs population, negative surface charge and high entrapment efficiency. The analysis of the thermosensitive gel allowed us to determine its rheological characteristics, showing that at 10°C gels owned a fluid-like behaviour meanwhile at 37°C they owned an elastic-like behaviour. Ca(OH)2-NPs-gel showed a prolonged drug release and the depth of penetration inside the dentinal tubules increased in the most apical areas. In addition, it was found that this drug did not produce irritation when applied to tissues such as eggs' chorialantoidonic membrane.

CONCLUSION

Calcium hydroxide-loaded PLGA NPs dispersed in a thermosensitive gel may constitute a suitable alternative as an intracanal antibacterial medicament.

Healing of apical periodontitis in type II diabetes mellitus patients: A prospective study

OBJECTIVE

This study aimed to compare the healing of periapical bone between type II diabetes patients and healthy patients after root canal treatment.

SUBJECTS AND METHODS

This study included 26 diabetic patients and the control group with healthy patients matching the diabetic group in age and sex. The study included only teeth with satisfactory coronal restoration. The periapical index system was used to evaluate the periapical status of treated teeth at follow-ups after 6 and 12 months.

RESULTS

Analysis of the results revealed a significantly higher healing rate in the control group compared to the diabetic group only at the 6-month follow-up (66.6 vs. 33.3%; Χ2 = 4.857; p = 0.0275). Analysis of the full-scale PAI index disclosed significantly higher PAI values in the diabetic subjects at 6- and 12-month follow-up. The regression analysis showed that the risk of apical periodontitis persistence increased significantly with female gender (OR = 3.92; 95% CI = 1.04-14.79; p = 0.043), diabetes mellitus (OR = 4.27; 95% CI: 1.18-15.50; p = 0.027) and higher household income (OR = 5.39; 95% CI = 1.33-21.89; p = 0.018).

CONCLUSION

Root canal treatment remains an effective means of conservative treatment in diabetic patients. While the healing is not compromised, regular follow-ups are necessary to monitor the healing process.

Elevated serum hepatic transaminases in apical periodontitis individuals

AIM

Apical periodontitis (AP) is the chronic inflammation of the periradicular tissues in response to root canal infection. Whilst AP has been linked with systemic inflammation and noncommunicable diseases, its potential association with nonalcoholic fatty liver disease (NAFLD) is unknown. We aimed to evaluate the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels as surrogate markers of hepatic injury, and the systemic inflammatory burden in otherwise healthy individuals with and without AP diagnosis.

METHODOLOGY

Cross-sectional study. Individuals with AP (n = 30) and healthy controls (n = 29) were recruited. The number, mean diameter (mm) and periapical index of the apical lesions of endodontic origin (ALEO) were assessed. ALT and AST levels (pg/mL) were measured through enzyme-linked immunosorbent assays. The serum levels of TNF-α, IL-4, IL-9, IL-10, IL-17A and IL-22 were evaluated by Multiplex assay. Inferential analysis was performed using t-test or Mann-Whitney tests according to data distribution and linear regression models. Data were analysed with StataV16 (p < .05).

RESULTS

ALT and AST levels were significantly higher in individuals with AP compared to controls (p < .05). Serum inflammatory biomarkers showed no significant differences between the study groups. Bivariate and multivariate analyses confirmed that AP diagnosis was independently associated with ALT and AST elevations (p < .05). Additionally, the number of ALEO positively influenced AST levels (p = .002). IL-22 on the other hand, was associated with reduced ALT levels (p = .043).

CONCLUSION

AP is associated with higher serum hepatic transaminases ALT and AST, potentially contributing to NAFLD physiopathology in young adults.

Outcomes of apexification in immature traumatised necrotic teeth and risk factors for premature tooth loss: A 20-year longitudinal study

BACKGROUND/AIM

To evaluate the long-term survival of immature traumatized incisors with pulp necrosis and apical periodontitis after endodontic treatment with two apexification techniques (calcium hydroxide apexification and MTA-apical plug) and to identify major factors affecting the survival of these teeth.

MATERIALS AND METHODS

Records of 2400 children and adolescents were screened for presence of traumatic dental injuries to immature incisors where endodontic treatment with the two apexification techniques was performed during January 2003 and December 2022, compared to a control group of mature teeth treated with conventional endodontic techniques. The studied variables were age; sex; apexification technique, presence of luxation and hard tissue injuries; preoperative root development stage (RDS), preoperative and postoperative periapical index (PAI), the time-point for tooth loss, and overall survival time in years. Kaplan-Meier estimates were used to graphically present the survival functions and Cox proportional hazard model to calculate hazard ratios (HR, 95% CI).

RESULTS

The median survival time was 10 years for calcium hydroxide apexification, 16.1 for MTA-apexification, for luxation injuries other than intrusions and avulsions 15.5 years, for intrusions 12.5 years and for avulsions 6.8 years. The variables with significant negative impact on tooth survival were calcium hydroxide apexification, avulsion and postoperative PAI 3-5. No significant relationships were found for the variables MTA apexification, concussion; subluxation; lateral luxation; extrusion, intrusion, hard tissue injuries, preoperative RDS and PAI scores and postoperative PAI 1-2. After adjustment, the risk for premature tooth loss was 13.5 times higher in calcium hydroxide apexification, approximately 2 to 4 times higher in PAI 3-5, and 5.6 times higher in avulsions.

CONCLUSIONS

Calcium hydroxide apexification, avulsion, and postoperative PAI 3-5 were identified as prognostic variables with significant negative impact on the risk for premature tooth loss.

Prevalence of Apical Periodontitis in Patients with Autoimmune Liver Diseases on Immune Suppressants and Immune Modulators: A Cross-sectional Study

INTRODUCTION

Autoimmune liver diseases (ALDs) are chronic conditions generated by an immune-mediated autoaggressive inflammatory reaction in genetically susceptible individuals. The purpose of this study was to evaluate the prevalence of apical periodontitis (AP) in patients suffering from ALDs undergoing treatment with the immune suppressants glucocorticoids, azathioprine, and/or ursodeoxycholic acid.

METHODS

The ALD group included 46 patients (11 men and 35 women, average age = 57.9 ± 11.8 years) and 1186 teeth. The control group included 50 healthy patients not taking any medications (15 men and 35 women, average age = 58.6 ± 10.4 years) and 1251 teeth. Demographic data and medical, pharmacologic, and dental history were recorded. Dental and radiographic examinations were performed. The presence of AP; the periapical index score; decayed, missing, and filled teeth; quality of restoration, and root canal treatment were evaluated. The influence of the medications the patients were taking on the prevalence of AP was also tested.

RESULTS

The prevalence of AP was significantly lower in ALDs than in the control group at the patient (P = .019) and tooth level (P = .014). Smoking and age were associated with a significant increase in AP in cases and controls (P = .045 and P = .001, respectively). In both groups, endodontically treated teeth showed a higher prevalence of AP.

CONCLUSIONS

Considering the limitations because of the observational nature of the study, the patients affected by ALDs liver diseases and undergoing treatment with immune suppressors (often associated with immune modulators) were found to exhibit a lower prevalence of AP.

Further Interventions after Root Canal Treatment Are Most Common in Molars and Teeth Restored with Direct Restorations: A 10-11-Year Follow-Up of the Adult Swedish Population

INTRODUCTION

The aims were to investigate 1) the frequency of nonsurgical retreatment, root-end surgery, extraction, and further restorative treatment during a follow-up of 10-11 years after root filling and compare the frequencies according to tooth group and type of coronal restoration and 2) the timing of nonsurgical retreatment, root-end surgery, and extraction.

METHODS

Data were collected from the Swedish Social Insurance Agency's register. A search for treatment codes identified teeth root filled in 2009 and the type of coronal restoration (direct, indirect, and unspecified) registered within 6 months of root filling. The root-filled teeth were followed 10-11 years, and further interventions were recorded. Descriptive statistics and chi-square tests were used for statistical analysis.

RESULTS

In 2009, root fillings were registered for 215,611 individuals/teeth. Nonsurgical retreatment, root-end surgery, and extraction were undertaken in 3.5%, 1.4%, and 20% teeth, respectively. The frequency of further interventions varied with respect to tooth group and type of coronal restoration, but only slightly for endodontic retreatments. Further interventions, except for root-end surgery, were registered more often for molars and directly restored teeth (P < .001). The majority of endodontic retreatments were undertaken within 4 years, while extractions were evenly distributed over 10-11 years.

CONCLUSIONS

The frequency numbers of nonsurgical retreatment and root-end surgery were low, despite 1 in 5 root-filled teeth registered as extracted. Further interventions were most common in molars and directly restored teeth. Endodontic retreatments were performed more often during the first 4 years.

A Dataset of apical periodontitis lesions in panoramic radiographs for deep-learning-based classification and detection

Deep learning has been studied in recent years to identify periapical lesions- a significant indicator of periapical periodontitis in radiographs. An accurate dataset is essential for constructing an efficient learning model for detecting periapical lesions. In order to achieve this goal, we gathered and created a database of panoramic radiographs containing periapical lesions from the High-quality Dental Treatment Centre, School of Dentistry, Hanoi Medical University, between January 2016 and March 2021. Out of 16,519 radiographs, three experienced dentists identified 3,926 images of periapical lesions and annotated those lesions based on the Periapical Lesions Classification. By applying well-known data processing techniques (e.g. scaling, mirroring, and flipping), the amount of data is increased to 17,004 images through generating additional images for machine learning. The dataset has three folders: one for the original photos, one for the post-augmentation images, and the rest for the annotation of periapical lesions. The information could assist researchers in developing a predictive machine model for detecting periapical lesions in radiographs.

Coaggregated E. faecalis with F. nucleatum regulated environmental stress responses and inflammatory effects

To investigate the cell-cell interactions of intergeneric bacterial species, the study detected the survival of Enterococcus faecalis (Ef) under monospecies or coaggregation state with Fusobacterium nucleatum subsp. polymorphum (Fnp) in environmental stress. Ef and Fnp infected the human macrophages with different forms (Ef and Fnp monospecies, Ef-Fnp coaggregates, Ef + Fnp cocultures) for exploring the immunoregulatory effects and the relevant molecular mechanisms. Meanwhile, the transcriptomic profiles of coaggregated Ef and Fnp were analyzed. Ef was shown to coaggregate with Fnp strongly in CAB within 90 min by forming multiplexes clumps. Coaggregation with Fnp reinforced Ef resistance against unfavorable conditions including alkaline, hypertonic, nutrient-starvation, and antibiotic challenges. Compared with monospecies and coculture species, the coaggregation of Ef and Fnp significantly facilitates both species to invade dTHP-1 cells and aid Ef to survive within the cells. Compared with coculture species, dual-species interaction of Ef and Fnp significantly decreased the levels of pro-inflammatory cytokines IL-6, TNF-α, and chemokines MCP-1 secreted by dTHP-1 cells and lessened the phosphorylation of p38, JNK, and p65 signaling pathways. The transcriptome sequencing results showed that 111 genes were differentially expressed or Ef-Fnp coaggregated species compared to Ef monospecies; 651 genes were differentially expressed for Fnp when coaggregation with Ef. The analysis of KEGG pathway showed that Ef differentially expressed genes (DEGs) were enriched in quorum sensing and arginine biosynthesis pathway; Fnp DEGs were differentially concentrated in lipopolysaccharide (LPS) biosynthesis, biofilm formation, and lysine degradation pathway compared to monospecies. KEY POINTS: • Coaggregated with Fnp aids Ef's survival in environmental stress, especially in root canals after endodontic treatment. • The coaggregation of Ef and Fnp may weaken the pro-inflammatory response and facilitate Ef to evade killed by macrophages. • The coaggregation between Ef and Fnp altered interspecies transcriptional profiles.

Antibacterial ability of different activated irrigation after root canal preparation: intratubular analyses

This study assessed the intratubular antibacterial ability of different activated irrigations after chemical mechanical preparation. Seventy-two palatal root canals of upper molars were infected with Enterococcus faecalis for 4 weeks, and then initial bacterial collection from the main root canal was performed. The root canals were prepared by using a WaveOne Gold large (45/.05) and distributed into 6 groups according to the activation of the final irrigation: ultrasonic activation (UA), XP-Endo Finisher (25/.00), XP Clean (25/.02), EasyClean (25/.04) in reciprocating motion and continuous rotary motion (ECRot), and conventional irrigation. After final irrigation, another bacterial collection from the main root canal was performed, and the root was sectioned transversely in three-thirds and stained for analysis by confocal laser microscopy. Intratubular bacteria were collected through dentin powder and plated for bacterial viability analysis. Intergroup and intragroup comparisons were performed by using analysis of variance and repeated measures analysis of variance, respectively, both at 5% significance. ECRot had higher antibacterial ability than UA (p<0.05), and both were superior to the other groups (p<0.05) in both methodologies. It can be concluded that activation of final irrigation enhances the disinfection of the root canal system, and activators have different efficacies.

Periapical lesion-derived decellularized extracellular matrix as a potential solution for regenerative endodontics

Pulp regeneration remains a crucial target in the preservation of natural dentition. Using decellularized extracellular matrix is an appropriate approach to mimic natural microenvironment and facilitate tissue regeneration. In this study, we attempted to obtain decellularized extracellular matrix from periapical lesion (PL-dECM) and evaluate its bioactive effects. The decellularization process yielded translucent and viscous PL-dECM, meeting the standard requirements for decellularization efficiency. Proteomic sequencing revealed that the PL-dECM retained essential extracellular matrix components and numerous bioactive factors. The PL-dECM conditioned medium could enhance the proliferation and migration ability of periapical lesion-derived stem cells (PLDSCs) in a dose-dependent manner. Culturing PLDSCs on PL-dECM slices improved odontogenic/angiogenic ability compared to the type I collagen group. In vivo, the PL-dECM demonstrated a sustained supportive effect on PLDSCs and promoted odontogenic/angiogenic differentiation. Both in vitro and in vivo studies illustrated that PL-dECM served as an effective scaffold for pulp tissue engineering, providing valuable insights into PLDSCs differentiation. These findings pave avenues for the clinical application of dECM's in situ transplantation for regenerative endodontics.

Periapical Lesions in Panoramic Radiography and CBCT Imaging-Assessment of AI's Diagnostic Accuracy

Background/Objectives: Periapical lesions (PLs) are frequently detected in dental radiology. Accurate diagnosis of these lesions is essential for proper treatment planning. Imaging techniques such as orthopantomogram (OPG) and cone-beam CT (CBCT) imaging are used to identify PLs. The aim of this study was to assess the diagnostic accuracy of artificial intelligence (AI) software Diagnocat for PL detection in OPG and CBCT images. Methods: The study included 49 patients, totaling 1223 teeth. Both OPG and CBCT images were analyzed by AI software and by three experienced clinicians. All the images were obtained in one patient cohort, and findings were compared to the consensus of human readers using CBCT. The AI's diagnostic accuracy was compared to a reference method, calculating sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), and F1 score. Results: The AI's sensitivity for OPG images was 33.33% with an F1 score of 32.73%. For CBCT images, the AI's sensitivity was 77.78% with an F1 score of 84.00%. The AI's specificity was over 98% for both OPG and CBCT images. Conclusions: The AI demonstrated high sensitivity and high specificity in detecting PLs in CBCT images but lower sensitivity in OPG images.

The prevalence of apical periodontitis in patients prior to hematopoietic cell transplantation: a systematic review

Objectives

This systematic review addressed the question: "What is the prevalence of apical periodontitis in patients prior to hematopoietic cell transplantation?"

Materials and Methods

A systematic search was conducted in MEDLINE/PubMed, Cochrane Library, Scopus, Web of Science, Embase, and Grey Literature Report. Eligibility criteria were based on the condition, content, and population strategy: the condition was the radiographic prevalence of apical periodontitis, the content comprised patients scheduled for hematopoietic stem cell transplantation, and the population consisted of adult and pediatric patients. The revised Risk of Bias in Nonrandomized Studies of Exposure tool was used to assess the quality of studies. The Grading Recommendations Assessments, Development, and Evaluation (GRADE) tool was used to assess the quality of evidence.

Results

Eight studies were included in this review. The average number of patients with apical periodontitis was 15.65% (range, 2.1%-43.34%). One study was classified as having a very high risk of bias, 1 with a high risk of bias, and 6 with some concern for bias. GRADE analysis showed a very low certainty of evidence. Significant limitations concerning the absence of control over confounding variables were identified.

Conclusions

With the caveat of the very low quality of evidence in the studies reviewed, there was a low to moderate prevalence of apical periodontitis in patients prior to undergoing hematopoietic cell transplantation.

The roles of stress-induced premature senescence and Akt/FoxO1 signaling in periapical lesions

OBJECTIVES

There is little knowledge about oxidative stress-induced senescence involvement in apical periodontitis. Here, we explored its molecular mechanism in periapical lesions.

METHODS

Ten cases of radicular cysts and five cases of periapical granulomas were randomly selected. Immunohistochemical analysis was performed to detect the expression and correlation between Senescence-associated factor polymerase I and transcript release factor (PTRF) and Akt/FoxO1 signaling. Human periodontal ligament cells (hPDLCs) pretreated with LY294002 were exposed to H2O2-induced oxidative stress conditions and then cell proliferation, senescence, apoptosis, and associated signaling were evaluated by EdU labeling, β-galactosidase assay, RT-qPCR, and western blot analysis, respectively.

RESULTS

Polymerase I and transcript release factor and Akt/FoxO1 signaling were more frequently expressed in the radicular cyst than in periapical granulomas. Notably, cells in radicular cysts showed Akt activation, FoxO1 phosphorylation, and cytoplasmic translocation. In vitro, prominent H2O2-induced senescence was observed in hPDLCs. LY294002, a PI3K inhibitor, attenuated the expression levels of senescence (Klotho, P16INK4), apoptosis (Bad, Fas), phosphorylated Akt, and phosphorylated FoxO1; however, did not affect cell proliferation.

CONCLUSIONS

Our data indicated that senescence is present in clinical periapical lesions, and Akt/FoxO1 signaling is involved in the H2O2-induced cellular senescence, which could serve as a potential therapeutic target.

Association between pulp and periapical disease with type 2 diabetes: A bidirectional Mendelian randomization

AIM

This current Mendelian randomization (MR) study aims to comprehensively explore the potential bidirectional link between pulp and periapical disease (PAP) with type 2 diabetes mellitus (T2DM).

METHODOLOGY

Summary level data of European-based population genome-wide association studies (GWASs) were employed to undertake this MR study. With the selection of single nucleotide polymorphisms (SNPs) as the instrumental variable, the radial inverse-variance weighted (radial IVW) method with modified second-order weights was applied as the primary method. Additionally, a range of sensitivity analyses were conducted to investigate pleiotropy. Results from different sources of outcome were pooled by meta-analysis with the fixed model.

RESULTS

The results of this MR analysis did not suggest a significant impact of pulp and periapical disease on type 2 diabetes (combined OR = 1.04, 95% CI: 1.00-1.07, p = .033) and vice versa (OR = 1.04, 95% CI: 0.96-1.14, p = .329). No significant pleiotropy was detected in the final model after the removal of outliers, demonstrating the reliability of the results in our primary analysis.

CONCLUSIONS

With the limitations inherent in the present MR study, there is no significant evidence in either direction to suggest a causal association between pulp and periapical disease and type 2 diabetes mellitus.

A 22-year follow-up cross-sectional study on periapical health in relation to the quality of root canal treatment in a Belgian population

AIM

To investigate the prevalence of apical periodontitis (AP) and the technical standard of root canal treatment in a Belgian population, assess the association of different variables with periapical status, and compare the results to a similar study conducted 22 years previously.

METHODOLOGY

In this cross-sectional study, 614 panoramic radiographs of first-time adult attendees at the Dental School of the University Hospital of Ghent were examined. Recorded patient-level parameters included gender, age, number of teeth, number of root filled teeth, presence of any AP lesion, and number of implants. The following tooth-level data were collected: tooth presence, coronal status, quality of coronal restoration, post presence, type of root-filling material, length and density of root filling, root-end filling material, presence of AP, and adjacent implant. Multivariable multilevel binary logistic regression was used to explore the association between patient and tooth characteristics and AP prevalence. Risk differences and confidence intervals were calculated to compare the present with the previous study.

RESULTS

The prevalence of AP at patient and tooth level was 46.9% and 5.6%, respectively. Fifty-one per cent of the 614 patients had at least one root filled tooth, and 5.9% of the 14 655 teeth studied were root filled. AP was found in 45% of root filled teeth. Fifty-four per cent of the root-filled teeth were rated as inadequate. Multivariable multilevel logistic regression revealed that more teeth, more implants, fewer root-filled teeth, adequate density, adequate coronal restoration, and no caries reduced the likelihood of AP. There were no statistically significant differences between the two studies regarding the prevalence of root-filled teeth or AP and the technical quality of root canal treatment.

CONCLUSIONS

The prevalence of AP and the technical quality of root canal treatment in Belgium have not substantially changed over the last 22 years, despite the technological advancements and continuing education in the field.

The role of Semaphorin 3A in oral diseases

Semaphorin 3A (SEMA3A), also referred to as H-Sema III, is a molecule with significant biological importance in regulating physiological and pathological processes. However, its role in oral diseases, particularly its association with inflammatory immunity and alveolar bone remodeling defects, remains poorly understood. This comprehensive review article aims to elucidate the recent advances in understanding SEMA3A in the oral system, encompassing nerve formation, periodontitis, pulpitis, apical periodontitis, and oral squamous cell carcinoma. Notably, we explore its novel function in inflammatory immunomodulation and alveolar bone formation during oral infectious diseases. By doing so, this review enhances our comprehension of SEMA3A's role in oral biology and opens up possibilities for modulatory approaches and potential treatments in oral diseases.

Prevalence of apical periodontitis and quality of root canal treatment in an adult Kuwaiti sub-population: a cross-sectional study

Objectives

This cross-sectional study evaluated the prevalence of apical periodontitis (AP) and the technical quality of root canal fillings in an adult Kuwaiti subpopulation using cone-beam computed tomography (CBCT) images.

Materials and Methods

Two experienced examiners analyzed 250 CBCT images obtained from Kuwaiti patients aged 15-65 years who attended government dental specialist clinics between January 2019 and September 2020. The assessment followed the radiographic scoring criteria proposed by De Moor for periapical status and the technical quality of root canal filling. Chi-square and Fisher's exact tests were used for statistical analysis, with significance level set at p < 0.05.

Results

Among the 2,762 examined teeth, 191 (6.91%) exhibited radiographic signs of AP, and 176 (6.37%) had undergone root canal filling. AP prevalence in root canal-treated teeth was 32.38%, with a significant difference between males and females. Most of the endodontically treated teeth exhibited adequate root canal filling (71.5%).

Conclusions

The study demonstrated a comparable prevalence of AP and satisfactory execution of root canal treatment compared to similar studies in different countries.

The effects of NLRP3 inflammasome inhibition or knockout in experimental apical periodontitis induced in mice

OBJECTIVE

To evaluate the effects of NLRP3 inflammasome inhibition or knockout in experimental apical periodontitis (AP) induced in mice.

METHODS

The experimental AP was induced by pulpal exposure. To evaluate NLRP3-specific inhibitor medication (MCC950), WT mice received intraperitoneal injections, while the control received PBS (n = 10). In addition, to evaluate NLRP3 knockout, 35 wild-type (WT) and 35 NLRP3-/- mice were divided into a control group (without pulpal exposure, n = 5) and three experimental groups: after 2, 14 and 42 days after pulpal exposure (n = 10). Microscopic and molecular analyzes were carried out using a significance level of 5%.

RESULTS

Exposure to MCC950 did not affect the periapical lesion size after 14 days (P = 0.584). However, exposed mice had a lower expression of IL-1β, IL-18 and caspase-1 (P = 0.010, 0.016 and 0.002, respectively). Moreover, NLRP3-/- mice showed a smaller periapical lesion after 14 and 42 days (P = 0.023 and 0.031, respectively), as well as a lower expression of IL-1β after 42 days (P < 0.001), of IL-18 and caspase-1 after 14 (P < 0.001 and 0.035, respectively) and 42 days (P = 0.002 and 0.002, respectively). NLRP3-/- mice also showed a lower mRNA for Il-1β, Il-18 and Casp1 after 2 (P = 0.002, 0.036 and 0.001, respectively) and 14 days (P = 0.002, 0.002 and 0.001, respectively).

CONCLUSIONS

NLRP3 inflammasome inhibition or knockout can attenuate the inflammatory events that result in the periapical lesion (AP) formation after pulpal exposure in mice.

CLINICAL RELEVANCE

The NLRP3 inflammasome may be a therapeutic target for AP, and new approaches may verify the impact of its inhibition (through intracanal medications or filling materials) on the bone repair process and treatment success.

Photodynamic and nitric oxide therapy-based synergistic antimicrobial nanoplatform: an advanced root canal irrigation system for endodontic bacterial infections

BACKGROUND

The main issues faced during the treatment of apical periodontitis are the management of bacterial infection and the facilitation of the repair of alveolar bone defects to shorten disease duration. Conventional root canal irrigants are limited in their efficacy and are associated with several side effects. This study introduces a synergistic therapy based on nitric oxide (NO) and antimicrobial photodynamic therapy (aPDT) for the treatment of apical periodontitis.

RESULTS

This research developed a multifunctional nanoparticle, CGP, utilizing guanidinylated poly (ethylene glycol)-poly (ε-Caprolactone) polymer as a carrier, internally loaded with the photosensitizer chlorin e6. During root canal irrigation, the guanidino groups on the surface of CGP enabled effective biofilm penetration. These groups undergo oxidation by hydrogen peroxide in the aPDT process, triggering the release of NO without hindering the production of singlet oxygen. The generated NO significantly enhanced the antimicrobial capability and biofilm eradication efficacy of aPDT. Furthermore, CGP not only outperforms conventional aPDT in eradicating biofilms but also effectively promotes the repair of alveolar bone defects post-eradication. Importantly, our findings reveal that CGP exhibits significantly higher biosafety compared to sodium hypochlorite, alongside superior therapeutic efficacy in a rat model of apical periodontitis.

CONCLUSIONS

This study demonstrates that CGP, an effective root irrigation system based on aPDT and NO, has a promising application in root canal therapy.

Physical training attenuates systemic cytokine response and tissue damage triggered by apical periodontitis

Apical periodontitis (AP) is a condition characterized by inflammatory and infectious components in the tooth canal. AP affects periradicular tissues and has systemic repercussions. Physical exercise is a structured activity that requires cardiorespiratory function, and can modulate the inflammatory profile in pathological conditions. As a result, this study aimed to determine the effects of aerobic physical training (PT) on the alveolar bone with and without AP, and its systemic inflammatory repercussions. AP was induced in the mandibular first molars, and PT was performed on a treadmill for five consecutive days over four weeks, with progressive increases in speed and activity time. Blood samples were collected to determine serum cytokine levels using immunoassays, and alveolar bone samples were collected for histopathological evaluation, lesion volume and microarchitecture assessment using computed microtomography. Animals with AP had increased pro-inflammatory cytokines levels compared to those without AP; however, these levels were attenuated or restored by PT. Compared to the AP group, the AP + PT group had a smaller lesion volume and greater preservation of the bone trabeculae in the remaining alveolar bone surrounding the lesion. In overall, PT minimized the severity of AP proving to be a valid strategy for individuals undergoing endodontic treatment.

A video-based decision aid improved knowledge and decreased decisional conflict for asymptomatic persistent endodontic lesions

AIM

This prospective cohort study aimed to (i) evaluate patients' treatment decisions, decisional conflict and knowledge levels before and after use of a video-based decision aid (DA) on asymptomatic persistent endodontic lesions (APEL) and to (ii) elicit important decision factors for patients in the decision-making process.

METHODOLOGY

A video DA modelled after the International Patient Decision Aids Standards (IPDAS) was designed. The video was pilot-tested, revised and used on 50 patients referred to the graduate endodontic clinic and presenting with an incidental finding of APEL detected on radiographs, with informed consent (DSRB 2020/00133). Recruitment was conducted from June 2020 to November 2021. Patients' treatment decisions and decision-making process were studied. Patients also completed a questionnaire on knowledge gain, decisional conflict and confidence levels.

RESULTS

Forty-three patients (48 teeth) out of 50 patients chose long-term monitoring of APEL while 7 patients (7 teeth) decided on endodontic intervention. Median knowledge scores increased from 58.3 (IQR: 41.7, 75.0) to 87.5 (IQR: 75.0, 100.0) (p < .001); median decisional conflict scale (DCS) scores decreased from 25.0 (IQR: 12.5, 34.4) to 3.1 (IQR: 0, 23.8) (p < .001), and 44 (88%) patients were confident or very confident with their treatment decisions. Statistical analyses showed that asymptomatic condition of tooth was the sole decision factor with statistical significance while socioeconomic factors (age, gender, race, education and income levels) showed no significant trend.

CONCLUSIONS

The majority of patients presenting with APEL in this study chose long-term monitoring over immediate intervention. Using the video-based DA in the decision-making process significantly improved patients' knowledge and decreased their decisional conflict levels.