Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults.

BACKGROUND: Dental pain can have a detrimental effect on quality of life. Symptomatic apical periodontitis and acute apical abscess are common causes of dental pain and arise from an inflamed or necrotic dental pulp, or infection of the pulpless root canal system. Clinical guidelines recommend that the first-line treatment for these conditions should be removal of the source of inflammation or infection by local operative measures, and that systemic antibiotics are currently only recommended for situations where there is evidence of spreading infection (cellulitis, lymph node involvement, diffuse swelling) or systemic involvement (fever, malaise). Despite this, there is evidence that dentists frequently prescribe antibiotics in the absence of these signs. There is concern that this could contribute to the development of antibiotic-resistant bacteria. This review is the second update of the original version first published in 2014. OBJECTIVES: To evaluate the effects of systemic antibiotics provided with or without surgical intervention (such as extraction, incision and drainage of a swelling, or endodontic treatment), with or without analgesics, for symptomatic apical periodontitis and acute apical abscess in adults. SEARCH METHODS: We searched Cochrane Oral Health's Trials Register (26 February 2018 (discontinued)), CENTRAL (2022, Issue 10), MEDLINE Ovid (23 November 2022), Embase Ovid (23 November 2022), CINAHL EBSCO (25 November 2022) and two trials registries, and performed a grey literature search. There were no restrictions on language or date of publication. SELECTION CRITERIA: Randomised controlled trials of systemic antibiotics in adults with a clinical diagnosis of symptomatic apical periodontitis or acute apical abscess, with or without surgical intervention (considered in this situation to be extraction, incision and drainage, or endodontic treatment) and with or without analgesics. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the results of the searches against inclusion criteria, extracted data and assessed risk of bias. We used a fixed-effect model in the meta-analysis as there were fewer than four studies. We contacted study authors to request missing information. We used GRADE criteria to assess the certainty of the evidence. MAIN RESULTS: There was one new completed trial on this topic since the last update in 2018. In total, we included three trials with 134 participants. Systemic antibiotics versus placebo with surgical intervention and analgesics for symptomatic apical periodontitis or acute apical abscess One trial (72 participants) compared the effects of a single preoperative dose of clindamycin versus a matched placebo when provided with a surgical intervention (endodontic chemo-mechanical debridement and filling) and analgesics to adults with symptomatic apical periodontitis. We assessed this study at low risk of bias. There were no differences in participant-reported pain or swelling across trial arms at any time point assessed. The median values for pain (numerical rating scale 0 to 10) were 3.0 in both groups at 24 hours (P = 0.219); 1.0 in the antibiotic group versus 2.0 in the control group at 48 hours (P = 0.242); and 0 in both groups at 72 hours and seven days (P = 0.116 and 0.673, respectively). The risk ratio of swelling when comparing preoperative antibiotic to placebo was 0.50 (95% confidence interval (CI) 0.10 to 2.56; P = 0.41). The certainty of evidence for all outcomes in this comparison was low. Two trials (62 participants) compared the effects of a seven-day course of oral phenoxymethylpenicillin (penicillin VK) versus a matched placebo when provided with a surgical intervention (total or partial endodontic chemo-mechanical debridement) and analgesics to adults with acute apical abscess or symptomatic necrotic tooth. Participants in both trials also received oral analgesics. We assessed one study at high risk of bias and the other at unclear risk of bias. There were no differences in participant-reported pain or swelling at any time point assessed. The mean difference for pain (short ordinal numerical scale 0 to 3, where 0 was no pain) was -0.03 (95% CI -0.53 to 0.47) at 24 hours; 0.32 (95% CI -0.22 to 0.86) at 48 hours; and 0.08 (95% CI -0.38 to 0.54) at 72 hours. The standardised mean difference for swelling was 0.27 (95% CI -0.23 to 0.78) at 24 hours; 0.04 (95% CI -0.47 to 0.55) at 48 hours; and 0.02 (95% CI -0.49 to 0.52) at 72 hours. The certainty of evidence for all the outcomes in this comparison was very low. Adverse effects, as reported in two studies, were diarrhoea (one participant in the placebo group), fatigue and reduced energy postoperatively (one participant in the antibiotic group) and dizziness preoperatively (one participant in the antibiotic group). Systemic antibiotics without surgical intervention for adults with symptomatic apical periodontitis or acute apical abscess We found no studies that compared the effects of systemic antibiotics with a matched placebo delivered without a surgical intervention for symptomatic apical periodontitis or acute apical abscess in adults. AUTHORS' CONCLUSIONS: The evidence suggests that preoperative clindamycin for adults with symptomatic apical periodontitis results in little to no difference in participant-reported pain or swelling at any of the time points included in this review when provided with chemo-mechanical endodontic debridement and filling under local anaesthesia. The evidence is very uncertain about the effect of postoperative phenoxymethylpenicillin for adults with localised apical abscess or a symptomatic necrotic tooth when provided with chemo-mechanical debridement and oral analgesics. We found no studies which compared the effects of systemic antibiotics with a matched placebo delivered without a surgical intervention for symptomatic apical periodontitis or acute apical abscess in adults.

Deciduous pulp tissue implantation into the root canal of mandibular incisor resulted in pulp revascularization: a case report with a 5-year follow-up.

To explore a new method to implant deciduous tooth pulp into the canal of young permanent teeth with necrotic pulps and apical periodontitis for the regenerative endodontic treatment of tooth no: 41 in a 7-year-old male. Briefly, 1.5% Sodium Hypochlorite (NaOCl) irrigation and calcium hydroxide-iodoform paste were used as root canal disinfectant at the first visit. After 2 weeks, the intracanal medication was removed, and the root canal was slowly rinsed with 17% Ethylene Diamine Tetraacetic Acid (EDTA), followed by flushing with 20 mL saline and then drying with paper points. Tooth no: 72 was extracted, and its pulp was extracted and subsequently implanted into the disinfected root canal along with induced apical bleeding. Calcium hydroxide iodoform paste was gently placed over the bleeding clot, and after forming a mineral trioxide aggregate (MTA) coronal barrier, the accessed cavities were restored using Z350 resin composite. The root developments were evaluated via radiographic imaging at 6 months, 1 year and 5 years after treatment. Imaging and clinical analysis showed closure of the apical foramen, thickening of the root canal wall, and satisfactory root length growth. Autologous transplantation might be useful to regenerate dental pulp in necrotic young permanent teeth.

Unveiling the oral-gut connection: chronic apical periodontitis accelerates atherosclerosis via gut microbiota dysbiosis and altered metabolites in apoE-/- Mice on a high-fat diet.

The aim of this study was to explore the impact of chronic apical periodontitis (CAP) on atherosclerosis in apoE-/- mice fed high-fat diet (HFD). This investigation focused on the gut microbiota, metabolites, and intestinal barrier function to uncover potential links between oral health and cardiovascular disease (CVD). In this study, CAP was shown to exacerbate atherosclerosis in HFD-fed apoE-/- mice, as evidenced by the increase in plaque size and volume in the aortic walls observed via Oil Red O staining. 16S rRNA sequencing revealed significant alterations in the gut microbiota, with harmful bacterial species thriving while beneficial species declining. Metabolomic profiling indicated disruptions in lipid metabolism and primary bile acid synthesis, leading to elevated levels of taurochenodeoxycholic acid (TCDCA), taurocholic acid (TCA), and tauroursodeoxycholic acid (TDCA). These metabolic shifts may contribute to atherosclerosis development. Furthermore, impaired intestinal barrier function, characterized by reduced mucin expression and disrupted tight junction proteins, was observed. The increased intestinal permeability observed was positively correlated with the severity of atherosclerotic lesions, highlighting the importance of the intestinal barrier in cardiovascular health. In conclusion, this research underscores the intricate interplay among oral health, gut microbiota composition, metabolite profiles, and CVD incidence. These findings emphasize the importance of maintaining good oral hygiene as a potential preventive measure against cardiovascular issues, as well as the need for further investigations into the intricate mechanisms linking oral health, gut microbiota, and metabolic pathways in CVD development.

The Role of Macrophage Efferocytosis in the Pathogenesis of Apical Periodontitis.

Macrophages (Mφs) play a crucial role in the homeostasis of the periapical immune micro-environment caused by bacterial infection. Mφ efferocytosis has been demonstrated to promote the resolution of multiple infected diseases via accelerating Mφ polarization into M2 type. However, the Mφ efferocytosis-apical periodontitis (AP) relationship has not been elucidated yet. This study aimed to explore the role of Mφ efferocytosis in the pathogenesis of AP. Clinical specimens were collected to determine the involvement of Mφ efferocytosis in the periapical region via immunohistochemical and immunofluorescence staining. For a further understanding of the moderator effect of Mφ efferocytosis in the pathogenesis of AP, both an in vitro AP model and in vivo AP model were treated with ARA290, a Mφ efferocytosis agonist. Histological staining, micro-ct, flow cytometry, RT-PCR and Western blot analysis were performed to detect the inflammatory status, alveolar bone loss and related markers in AP models. The data showed that Mφ efferocytosis is observed in the periapical tissues and enhancing the Mφ efferocytosis ability could effectively promote AP resolution via facilitating M2 Mφ polarization. Collectively, our study demonstrates the functional importance of Mφ efferocytosis in AP pathology and highlights that accelerating Mφ efferocytosis via ARA290 could serve as an adjuvant therapeutic strategy for AP.

Atypical healing of an endodontic lesion following emergency treatment: a case report.

This case report examines the atypical healing of an endodontic lesion without standard endodontic treatment, influenced by the patient's failure to attend treatment appointments. A 50-year-old woman with no notable medical history presented with a deep carious lesion on her mandibular right first molar, accompanied by localized pain. Citing forgetfulness as a reason, the patient missed her initially scheduled root canal treatment, necessitating an emergency intervention. The emergency treatment included access cavity preparation, irrigation with 5.25% sodium hypochlorite solution, application of a modified triple antibiotic paste (equal parts penicillin G, metronidazole, and ciprofloxacin), and temporary restoration with amalgam. A large apical lesion was detected in immediate postoperative radiographs. However, the patient failed to return for definitive endodontic treatment, due to a lack of symptoms and time for treatment. Follow-up examinations 1 and 5 years after emergency treatment disclosed gradual healing of the lesion, culminating in the establishment of a normal periodontal ligament. This case underscores the potential efficacy of a modified triple antibiotic paste and highlights the importance of a well-sealed coronal restoration in promoting the healing of endodontic lesions, even in the absence of pulpectomy and conventional root canal therapy. Additional research is needed to understand the mechanisms behind such healing events.

[Study on the antimicrobial effect of new bioactive glass against common bacteria in apical periodontitis of deciduous teeth].

PURPOSE: To study the antimicrobial effect of different concentrations of new bioactive glass(BG) on common bacteria in apical periodontitis of deciduous teeth. METHODS: The diameter (mm) of the inhibitory rings formed after treatment of Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum with the new bioactive glass was detected and observed by paper diffusion method, and the minimal inhibitory concentration(MIC), minimal bactericidal concentration (MBC) and minimal biofilm eradication concentration (MBEC) of E. faecalis, P. gingivalis and C. pseudomallei were determined. The mixed plaques of the three bacteria were treated with 20, 40, 60 and 80 mg/mL of the new bioactive glass for 24 h. The results were analyzed by laser confocal microscopy. The antibacterial effect of the new bioactive glass on the mixed plaque was observed by confocal laser scanning microscopy (CLSM). Statistical analysis was performed with GraphPad Prism 10.0 software. RESULTS: The new bioactive glass showed strong antibacterial potential against the common bacteria of apical periodontitis; the MBEC of the new bioactive glass on the plaque was significantly greater than MIC and MBC of Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum, and as the concentration of the new bioactive glass increased, the number of dead bacteria in the mixed plaque increased, and there was significant difference from that of the blank control group (P＜0.05). CONCLUSIONS: The novel bioactive glass shows significant antibacterial efficacy against Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum, which are the common bacteria in apical periodontitis of deciduous teeth.

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.

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-1ß, 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-1ß 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-1ß, 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.

Dental findings frequently overlooked in sinus computed tomography reports.

OBJECTIVES: Computed tomography (CT) and cone beam computed tomography (CBCT) represent the main imaging modalities used in rhinosinusitis patients and are also important in odontogenic sinusitis (OS) diagnostics. Reports, however, often lack information on dentition. Here, we aimed to determine how maxillary dentition is initially interpreted in rhinosinusitis patients' CT/CBCT reports and which dental findings in particular are potentially missed, thus needing more attention. STUDY DESIGN: CT/CBCT scans and radiological reports from 300 rhinosinusitis patients were analysed focusing specifically on dental findings. An experienced oral and maxillofacial radiologist re-evaluated the scans and the assessment was compared to the original reports using the McNemar test. RESULTS: From the 300 original reports, 233 (77.7%) mentioned the maxillary teeth. The most frequent statement (126/300, 42.0%) was 'no apical periodontitis'. Apical periodontitis and severe alveolar bone loss were significantly overlooked (p < 0.001). Amongst the 225 patients for whom the CT/CBCT report initially lacked information on dental pathology, 22 patients were diagnosed with apical periodontitis and 16 with severe alveolar bone loss upon re-evaluation. CONCLUSIONS: Dental pathology remains underreported in rhinosinusitis patients' CT/CBCT reports. Because these reports affect OS diagnostics, a routine and structured review of the maxillary teeth by a radiologist is necessary. Such examinations should encompass the maxillary teeth.

Intracanal microbiome profiles of two apical periodontitis cases in one patient: A comparison with saliva and plaque profiles.

OBJECTIVES: To determine the characteristics of the endodontic microbiome. MATERIAL AND METHODS: Saliva, plaque, and infected root canal wall dentin of two teeth suffering from apical periodontitis were harvested from a 58-year-old man. Bacterial DNA was extracted from each sample, and 16S rRNA gene analysis targeting the V3-V4 region was conducted on the Illumina MiSeq platform using QIIME2. The functional potential of the microbiomes was inferred using PICRUSt2. RESULTS: The four microbiomes were different in structure and membership, yet the nine most abundant metabolic pathways were common among them. The two endodontic microbiomes were more anaerobic, rich in Firmicutes, and scarce in Actinobacteriota and Proteobacteria, compared with saliva and plaque microbiomes. Their profiles were dissimilar despite their clinical and radiographic similarities. CONCLUSIONS: The endodontic microbiomes were anaerobic, rich in Firmicutes, scarce in Actinobacteriota and Proteobacteria, and considerably varied within an individual.

Effect of EGCG-based paste as intracanal dressing, in MMPs 2 and 9 expression in dog's periapical lesions.

High expression of MMP-2 and MMP-9 in periapical lesions plays an important role in the degradation of the extracellular matrix. This study aimed to investigate the effect of epigallocatechin-3-gallate (EGCG)-based endodontic paste as an intracanal dressing on the expression of MMP-2 and MMP-9 in periapical lesions. Periapical lesions were experimentally induced in 35 mature beagle dog premolars randomly divided into healthy teeth, untreated periapical lesions, periapical lesions treated in a single session (control groups), and periapical lesions treated in two sessions with EGCG or calcium hydroxide-based pastes (experimental groups). After 120 days, specimens were obtained for histopathologic and immunofluorescence analyses to assess the expression of MMP-2 and MMP-9. The statistical analysis was performed using a p-value of 0.05. Endodontic treatment in two sessions using medication with EGCG and calcium hydroxide-based pastes provided similar repair of the apical and periapical tissues and neoformation of periodontal ligament fibers, cementum, and alveolar bone (p>0.05). The experimental groups treated in two sessions with both medications presented expression of MMP-2 and MMP-9 similar to that in healthy teeth (p>0.05), and significantly lower than teeth treated in a single session or untreated periapical lesions (p <0.001). Expression of MMP-2 and MMP-9 was observed in the cytoplasm of fibroblasts, osteoblasts, cementoblasts, cementocytes, and vascular endothelium. The use of EGCG-based endodontic paste reduced the expression of MMP-2 and MMP-9 and allowed repair of periapical lesions, similar to calcium hydroxide-based paste, and superior to treatment performed in a single session.

Predictors of apical periodontitis in root canal treated teeth from an adult Nepalese subpopulation: a cross-sectional study.

BACKGROUND: Endodontic literature search revealed that no study has been conducted to evaluate the prevalence of apical periodontitis (AP) in root canal treated teeth from an adult Nepalese population of Madhesh Province. Consequently, little is known about the extent and risk factors associated with it. This study aimed to determine AP prevalence in root canal treated teeth from an adult Nepalese subpopulation and to analyze the related risk factors including age, sex, tooth type, type of coronal restoration and quality of root canal treatment and coronal restoration as predictors of AP. METHODS: Digital panoramic radiographs were evaluated. Periapical status of 300 root canal-treated teeth was scored by using the periapical index. The quality of root canal treatment and coronal restorations were categorized as adequate or inadequate through radiographic and clinical evaluation. The data were analyzed using univariate and multivariate logistic regression models. RESULTS: Prevalence of AP in the present study was 31.7%. In 45.7% of the treated teeth, quality of root canal treatment was adequate whereas 46% of the cases had adequate coronal restorations. Multivariate logistic regression analysis revealed statistically significant associations and remarkably increased risk for AP in teeth with inadequate root canal treatment (odds ratio [OR] = 7.92; 95% CI: 3.96-15.82; p < 0.001) whereas lower risk for AP was found in females (OR = 0.51; 95% CI: 0.28-0.90; p = 0.021) and in teeth restored with crown (OR = 0.22; 95% CI: 0.09-0.51; p < 0.001) and filling (OR = 0.18; 95% CI: 0.08-0.42; p < 0.001). Quality of coronal restoration, tooth type and age of the patient were not found to be the predictors of AP. CONCLUSIONS: Within the limits of this study, a high prevalence of AP and poor overall quality of root canal treatment and coronal restoration was found in the subpopulation studied. Quality of root canal treatment, type of coronal restoration and sex of the patient are significant predictors of possible AP development in root canal treated teeth. Substantial efforts are needed to improve the endodontic treatment standards.

Pathogenic factors of maxillary sinus mucosal thickening observed by cone-beam computed tomography (CBCT).

OBJECTIVE: To explore the pathogenic factors associated with maxillary sinus mucosal thickening with Cone-beam computed Tomography (CBCT). METHODS: From 2016 through 2020, 93 patients with periapical periodontitis or periodontitis in the maxillary posterior dental region were selected. RESULTS: The preoperative thickness of the periodontitis group was significantly higher than that of the periapical periodontitis group (P < 0.05). The difference achieves statistical significance for the comparison of the thickness change with various severity of inflammation (F = 54.824, P = 0.000), the change with time (F = 312.741, P = 0.000). and the change with the interaction severity of inflammation and time（F = 86.132, P = 0.000). CONCLUSIONS: Patients with maxillary sinus mucosa thickening caused by periodontitis and periapical periodontitis should be extracted their infectious teeth and get thoroughly debridement. Maxillary sinus augmentation can perform favorable efforts 3-6 months after extracting teeth.

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.

Clinical and Radiographic Failure of Nonsurgical Endodontic Treatment and Retreatment Using Single-cone Technique With Calcium Silicate-based Sealers: A Systematic Review and Meta-analysis.

INTRODUCTION: This systematic review and meta-analysis aimed to evaluate the clinical and radiographic failure of nonsurgical endodontic treatment and retreatment for mature permanent teeth with or without apical periodontitis using the single-cone (SC) obturation technique with calcium silicate-based bio-ceramic (CSBC) sealers and to compare these failure rates to other sealer materials and obturation techniques. METHODS: A comprehensive search was conducted using MEDLINE (PubMed), Embase, Cochrane Library, Scopus, Web of Science, and gray literature up to March 2023. Two reviewers assessed the eligibility of the included studies. Eligible studies were critically appraised for risk of bias and quality of evidence. Subsequently, a meta-analysis of pooled data was conducted utilizing the RevMan software (P < .05) to evaluate the failure rate of non-surgical root canal therapy using CSBC sealers and SC obturation procedures. Separately, another analysis was conducted to compare those results with the outcome of nonsurgical root canal therapy using alternative obturation materials and methods. RESULTS: Five studies were included. The pooled failure rate for nonsurgical endodontic treatment and retreatment combined using CSBC sealers and SC obturation technique was 6.8% [95% confidence interval (CI) = (3%-12%), I2 = 46%]. A second analysis was conducted on the 3 included clinical trials to compare the outcomes of the intervention (CSBC sealers and SC obturation technique) and control groups (other sealers and other obturation techniques). This analysis found no significant difference between the 2 groups regarding clinical and radiographic failure of endodontic treatment and retreatment [Risk ratio = 0.71, 95% CI = (0.33, 1.51), I2 = 0]. This difference was also not statistically significant when the failure rate of primary root canal treatment and retreatment were separately analyzed [Combined Risk ratio of primary root canal treatment = 0.94, 95% CI = (0.46, 1.93), I2 = 0%; Combined Risk ratio of retreatment = 0.21, 95% CI = (0.001, 75.46), I2 = 0%]. CONCLUSIONS: The overall results of this systematic review and meta-analysis demonstrate that the SC obturation technique with CSBC sealer provides similar results compared to other obturation materials and techniques in facilitating the healing of apical periodontitis.

Characterization of cells in blood evoked from periapical tissues in immature teeth with pulp necrosis and their potential for autologous cell therapy in Regenerative Endodontics.

OBJECTIVE: The objectives of this study were to isolate, characterize progenitor cells from blood in the root canals of necrotic immature permanent teeth evoked from periapical tissues and evaluate the applicable potential of these isolated cells in Regenerative Endodontics. DESIGN: Ten necrotic immature permanent teeth from seven patients were included. Evoked bleeding from periapical tissues was induced after chemical instrumentation of the root canals. Cells were isolated from the canal blood and evaluated for cell surface marker expression, multilineage differentiation potential, proliferation ability, and target protein expression. Cell sheets formed from these cells were transferred into human root segments, and then transplanted into nude mice. Histological examination was performed after eight weeks. Data analysis was conducted using one-way ANOVA followed by Tukey's post-hoc comparison, considering p < 0.05 as statistically significant. RESULTS: The isolated cells exhibited characteristics typical of fibroblastic cells with colony-forming efficiency, and displayed Ki67 positivity and robust proliferation. Flow cytometry data demonstrated that at passage 3, these cells were positive for CD73, CD90, CD105, CD146, and negative for CD34 and CD45. Vimentin expression indicated a mesenchymal origin. Under differentiation media specific differentiation media, the cells demonstrated osteogenic, adipogenic, and chondrogenic differentiation potential. Subcutaneous root canals with cell sheets of isolated cells in nude mice showed the formation of pulp-like tissues. CONCLUSIONS: This study confirmed the presence of progenitor cells in root canals following evoked bleeding from periapical tissues of necrotic immature teeth. Isolated cells exhibited similar immunophenotype and regenerative potential with dental mesenchymal stromal cells in regenerative endodontic therapy.

Influence of the severity of periodontal disease on the outcome of non-surgical endodontic therapy: A prospective cohort study.

OBJECTIVE: To investigate the influence of severity of periodontal disease on periapical healing after non-surgical endodontic therapy (NSET). MATERIAL AND METHODS: In this prospective study, subjects (n = 45) requiring NSET in a mandibular molar tooth with the diagnosis of pulp necrosis and asymptomatic apical periodontitis exhibiting radiographic periapical index (PAI) score ≥ 3 and concomitant endodontic periodontal lesion (CEPL) without communication were enrolled. After dividing as per the classification of Periodontal and Peri-Implant Diseases and Conditions, subjects were equally allocated into three groups. Group I- only endodontic lesion {control: healthy periodontium (n = 15)}, Group II- CEPL having stage I and II periodontitis (n = 15) and Group III- CEPL having stage III periodontitis (n = 15). Standardized two-visit NSET was performed with 2% chlorhexidine gel as an intracanal medicament. Periodontal therapy was instituted wherever required. Subjects were recalled at 6-and 12-months for clinical and radiographic assessment. Chi-square test was performed to evaluate the difference between the groups. RESULTS: At 12-month follow-up, all teeth in the three study groups were asymptomatic. On radiographic evaluation of the periapical region, healing was observed in 80%, 47% and 50% of teeth in Groups I, Group II and Group III, respectively. However, the difference was not statistically significant between the groups (p = 0.150). CONCLUSION: The severity of periodontal disease had no influence on periapical healing after NSET in teeth with concomitant endodontic periodontal lesions without communication. CLINICAL RELEVANCE: Periodontal disease has significant impact on apical periodontitis however severity of the periodontitis does not negatively impact the apical periodontitis.

Metformin switches cell death modes to soothe the apical periodontitis via ZBP1.

Apical periodontitis (AP) is a disease caused by pathogenic microorganisms and featured with the degradation of periapical hard tissue. Our recent research showed the crucial role of Z-DNA binding protein 1 (ZBP1)-mediated necroptosis and apoptosis in the pathogenesis of AP. However, the specific regulatory mechanisms of ZBP1 in AP are not fully elucidated. It was found that metformin has a regulatory role in cell necroptosis and apoptosis. But whether and how metformin regulates necroptosis and apoptosis through the ZBP1 in the context of AP remains unknown. This study provided evidence that lipopolysaccharide (LPS) promotes the synthesis of left-handed Z-nucleic acids (Z-NA), which in turn activates ZBP1. Knockout of Zbp1 by CRISPR/Cas9 technology significantly reduced LPS-induced necroptosis and apoptosis in vitro. By using Zbp1-knockout mice, periapical bone destruction was alleviated. Moreover, type I interferon induced the expression of interferon-stimulated genes (ISGs), which serve as a major source of Z-NA. In addition, the RNA-editing enzyme Adenosine Deaminase RNA specific 1 (ADAR1) prevented the accumulation of endogenous Z-NA. Meanwhile, metformin suppressed the ZBP1-mediated necroptosis by inhibiting the expression of ZBP1 and the accumulation of ISGs. Metformin also promoted mitochondrial apoptosis, which is critical for the elimination of intracellular bacterial infection. The enhanced apoptosis further promoted the healing of infected apical bone tissues. In summary, these results demonstrated that the recognition of Z-NA by ZBP1 plays an important role in AP pathogenesis. Metformin suppressed ZBP1-mediated necroptosis and promoted apoptosis, thereby contributing to the soothing of inflammation and bone healing in AP.

Comparation of the effectiveness of conventional needle irrigation and photon-induced photoacoustic streaming with sodium hypochorite in the treatment of teeth with apical periodontitis: a randomized clinical trial.

Photon-initiated photoacoustic streaming (PIPS) with an Er: YAG laser has been introduced in root canal treatment to improve irrigation and facilitate the removal of bacteria in the root canal system. This study aimed to compare the antibacterial effectiveness of two different root canal irrigation techniques, conventional needle irrigation (CNI) and PIPS, using 1% sodium hypochlorite (NaOCl), in the treatment of teeth with apical periodontitis. Sixty patients with a total of sixty teeth affected by apical periodontitis were included in this study. The teeth underwent root canal therapy, and after mechanical instrumentation, they were randomly assigned to two groups (n = 30) based on the final irrigation protocol: CNI or PIPS with 1% NaOCl. Bacterial suspensions in the root canals were evaluated using Adenosine 5'-triphosphate (ATP) assay kit after mechanical instrumentation and after final irrigation. Then, a follow-up was conducted after 7 days. The results revealed that final irrigation significantly reduced ATP values in both the CNI and PIPS groups (P < 0.001). The ATP values after final irrigation was greater in the CNI group compared to the PIPS group (P < 0.001). After a 7-day follow-up, percussion tenderness and fistula were significantly resolved in both groups (P < 0.05). A multivariate linear regression model was used to identify the factors that influence post irrigation ATP values. The analysis demonstrated that pre-operative percussion tenderness (P = 0.006), the presence of a fistula (P < 0.001) and the method used in the final irrigation (P < 0.001) had a significant impact on the ATP value after final irrigation. These results indicate that employing PIPS with 1% NaOCl as the final irrigation protocol exhibited superior antibacterial effectiveness and has the potential to enhance clinical outcomes in the treatment of teeth afflicted with apical periodontitis.