Prevalence Studies on Root Canal Anatomy Using Cone-beam Computed Tomographic Imaging: A Systematic Review

Introduction

In the literature, several prevalence studies on root canal anatomy using cone-beam computed tomographic technology are currently available although their results remain disperse. This systematic review aimed to appraise and combine, under strict criteria conditions, selected prevalence studies in order to comprehend the distribution of root canal configuration types among different populations.

Ultrasonic Irrigant Activation during Root Canal Treatment: A Systematic Review

Introduction

The aim of this study was to systematically review the evidence on the cleaning and disinfection of root canals and the healing of apical periodontitis when ultrasonic irrigant activation is applied during primary root canal treatment of mature permanent teeth compared with syringe irrigation.

Prevalence of Apical Periodontitis and Conventional Nonsurgical Root Canal Treatment in General Adult Population: An Updated Systematic Review and Meta-analysis of Cross-sectional Studies Published between 2012 and 2020

IntroductionThis study aimed to summarize data on apical periodontitis (AP) and nonsurgical root canal treatment (NSRCT) prevalence and risk factors related to age, gender, and quality of restorative and endodontic treatment in the general population from cross-sectional studies published between 2012 and 2020.MethodsAn electronic search was performed in the following databases: Web of Science, Scopus, and PubMed. The conducted literature search covered studies published between 2012 and 2020, without restrictions on language. The STROBE and NOS tools were used for quality assessment of the included studies.ResultsSixteen articles were included in the review. In total, 200,041 teeth were examined. On average, 6.3% of teeth had AP, and 7.4% had NSRCT. Forty-one percent of RCT teeth had AP, and 3.5% of untreated teeth had AP. Female patients were less prone to AP in endodontically treated teeth only, compared with male patients (P < .001). Variable stratification of age subgroups among included studies prevented us from conducting a meta-analysis. An increase in AP frequency was found in teeth with inadequate restorative and endodontic treatment (P < .001 and P < .001, respectively). Because of high heterogeneity, these results should be taken with caution.ConclusionsThere is an increased AP prevalence in the adult general population compared with data from 2012 (6.3% versus 5.4%) in both endodontically treated (41.3% versus 35.9%) and untreated teeth (3.5% versus 2.1%). In addition, AP developed less frequently in female patients with endodontically treated teeth and in teeth with inadequate compared with adequate restorative and endodontic treatment.     

The Effect of Photodynamic Therapy in Root Canal Disinfection: A Systematic Review

Introduction

Effective root canal disinfection is a fundamental component of successful root canal treatment. Photodynamic therapy (PDT) has been proposed as a new adjunctive method for additional disinfection of the root canal system with the possibility of improved treatment outcomes. The aim of this systematic review was to investigate the effect of PDT on bacterial load reduction during root canal disinfection.

Methods

Two reviewers independently conducted a comprehensive literature search using a combination of medical subject heading terms and key words to identify studies relevant to the Population Intervention Control Outcome question. The selection of articles for inclusion was performed in 2 phases based on predetermined eligibility criteria according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Inter-reviewer agreement for each phase was recorded. The effect of PDT on bacterial load reduction during root canal disinfection was evaluated as the primary outcome variable during data extraction.

Results

The literature search provided 57 titles and abstracts. Three articles met the inclusion criteria and were selected for this systematic review. The reasons for study exclusion in each phase were recorded. Because of the heterogeneity in clinical indications and PDT protocols among the included studies, a meta-analysis could not be performed. All included studies showed a positive effect of PDT in the reduction of microbial load in root canal treatment ranging from 91.3%–100%.

Conclusions

Limited clinical information is currently available on the use of PDT in root canal disinfection. If supported by future clinical research, PDT may have efficacy for additional root canal disinfection, especially in the presence of multi–drug-resistant bacteria.     

Nature and Prevalence of Bacterial Taxa Persisting after Root Canal Chemomechanical Preparation in Permanent Teeth: A Systematic Review and Meta-analysis

IntroductionCulture-independent molecular studies have shown a broad spectrum of bacterial taxa that persist after chemomechanical procedures (CMP). Therefore, this study systematically reviewed these reports to explore the prevalence of bacteria in post-instrumentation samples of root canals from permanent teeth, especially of as-yet-uncultivated/difficult-to-culture bacteria.MethodsElectronic databases were searched from 2007 to January 2021. Clinical studies using culture-independent molecular methods to identify species-level taxa before and after CMP were included. Studies were critically appraised using the Joanna Briggs Institute Prevalence Critical Appraisal Checklist and the funnel plot analysis. The meta-analysis was performed on the prevalence of as-yet-uncultivated/difficult-to-culture bacterial taxa using RStudio.ResultsA total of 3781 titles were screened, but only 20 studies were included. The most frequent species in post-instrumentation samples were Streptococcus spp., Leptotrichia buccalis, Fusobacterium nucleatum, and Capnocytophaga ochracea. The detection frequency of some species increased after CMP, including mainly Firmicutes members such as streptococci, Enterococcus faecium, Selenomonas noxia, and Solobacterium moorei. The prevalence (confidence interval) of difficult-to-culture species was as follows: Dialister invisus, 17% (7%–29%); Solobacterium moorei, 14% (8%–23%); Bacteroidaceae [G-1] bacterium HMT 272, 13% (5%–23%); and Filifactor alocis, 11% (3%–23%).ConclusionsThe prevalence of as-yet-uncultivated/difficult-to-culture bacterial taxa in post-instrumentation samples was low. The persistent species belonged mainly to the phylum Firmicutes, and streptococci were the major members. Future larger clinical studies on the composition of the whole bacterial community that persist after CMP are still necessary for a better understanding of bacterial interactions and their clinical significance in the treatment outcome.     

Machine-assisted Agitation Reduces Postoperative Pain during Root Canal Treatment: A Systematic Review and Meta-analysis from Randomized Clinical Trials

Introduction

This systematic review and meta-analysis aimed to assess whether machine-assisted agitation resulted in less postoperative pain (PP) compared with syringe irrigation with needle alone in adult patients undergoing root canal treatment.

急性根尖周炎患牙治疗前后前列腺素E-2水平的变化

目的　检测急性根尖周炎患牙治疗前后根管渗出液中前列腺素E2水平的变化。方法　用同位素放射免疫法测定25例急性根尖周炎患牙治疗前后根管内渗出液中前列腺素E2含量的变化。结果　急性根尖周炎患牙治疗前后前列腺素E2的含量明显不同,治疗前明显高于治疗后。结论　前列腺素E2水平的变化与根尖周炎临床表现之间有着密切的关系,根管渗出液中前列腺素E2浓度反映出根尖周炎的活动性。     

Outcome of Root Canal Treatment in Dogs Determined by Periapical Radiography and Cone-Beam Computed Tomography Scans

The purpose of this study was to compare the favorable outcome of root canal treatment determined by periapical radiographs (PRs) and cone beam computed tomography (CBCT) scans. Ninety-six roots of dogs' teeth were used to form four groups (n= 24). In group 1, root canal treatments were performed in healthy teeth. Root canals in groups 2 through 4 were infected until apical periodontitis (AP) was radiographically confirmed. Roots with AP were treated by one-visit therapy in group 2, by two-visit therapy in group 3, and left untreated in group 4. The radiolucent area in the PRs and the volume of CBCT-scanned periapical lesions were measured before and 6 months after the treatment. In groups 1, 2, and 3, a favorable outcome (lesions absent or reduced) was shown in 57 (79%) roots using PRs but only in 25 (35%) roots using CBCT scans (p = 0.0001). Unfavorable outcomes occurred more frequently after one-visit therapy than two-visit therapy when determined by CBCT scans (p = 0.023).     

Diabetes Mellitus and Periapical Abscess: A Cross-sectional Study

IntroductionDental morbidities associated with diabetes mellitus (DM) include an increased prevalence of periodontal diseases (PDs). However, the occurrence of periapical infections in DM has not been sufficiently documented in the literature. The purpose of this study was to investigate the occurrence of periapical abscesses (PAs) in type 1 DM (T1DM) patients, type 2 DM (T2DM) patients, and nondiabetics in a hospital-based population.MethodsWe conducted a cross-sectional study by accessing the University of Florida Health Integrated Data Repository, and diagnoses of T1DM, T2DM, and PA were obtained from queries using the International Statistical Classification of Diseases, 10th Revision. The following parameters were recorded: age, sex, and race. A logistic regression model for aggregated data was used to assess the association between the occurrence of PA and the diabetic groups (T1DM, T2DM, and nondiabetic groups) after adjusting for PDs and cardiovascular disease (CVD).ResultsAmong 867,526 patients, we found 5260 (0.6%) with T1DM and 52,493 (6.1%) with T2DM. The prevalence of PAs in the total hospital population was 4923 (0.6%), 102 patients (1%) with T1DM and 766 (6%) with T2DM with statistically significant differences. In subjects without PDs, diabetic patients are almost 3 times likely to have PAs compared with nondiabetic subjects. Among subjects with PDs, the association is weaker (odds ratio = 1.35) but still significant at a level of 0.05. In subjects without CVD, DM subjects are greater than 3 times more likely to have PA, whereas among subjects with CVD, subjects with DM are 1.5 times more likely to have PA.ConclusionsA higher prevalence of PAs was reported in diabetic patients compared with the other hospital population. Comprehensive dental treatment should be administered to diabetic patients to maximize glycemic control.     

Mental Foramen and Anterior Loop Anatomic Characteristics: A Systematic Review and Meta-analysis of Cross-sectional Imaging Studies

IntroductionThe present study aimed to review the epidemiologic, topographic, and morphometric aspects of the mental foramen (MF) and anterior loop (AL) on cone-beam computed tomographic imaging studies.MethodsAn International Prospective Register of Systematic Reviews (PROSPERO)-registered systematic review (CRD42018112991) was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Two reviewers independently performed data extraction from observational studies that evaluated MF and AL on 7 electronic databases. MedCalc (MedCalc Software bv, Ostend, Belgium) software was used to perform a meta-analysis with a 95% confidence level.ResultsOf 1545 articles, 66 met the inclusion criteria, totaling 14,233 patients from 5 continents, with a total of 6655 females and 5884 males (some studies did not report sex), with an age range between 8 and 89 years. The most prevalent shapes of MF were oval (48.72%) and circular (44.36%), and the most frequent horizontal positions were between premolars (43.66%) and in line with the long axis of the second premolar (43.12%).ConclusionsBased on the articles that assessed AL, the mean prevalence was 43.18%, with most studies reporting bilateral localization as the most prevalent.     

Effectiveness of Intracanal Cryotherapy in Root Canal Therapy: A Systematic Review and Meta-analysis of Randomized Clinical Trials

IntroductionThe effectiveness of intracanal cryotherapy for reducing postoperative pain is unclear. The objective of this systematic review was to evaluate the effect of intracanal cryotherapy on postoperative pain after root canal therapy in patients with pulpal or periradicular pathosis.MethodsWe searched PubMed, Embase, Scopus, and the Cochrane Library as well as the top 3 endodontic journals for relevant articles. We included randomized controlled trials that included adults. Our main outcome was postoperative pain intensity measured with a validated scale. We assessed the risk of bias using the Cochrane criteria and the quality of the included studies using Grading of Recommendation Assessment, Development, and Evaluation. We used a random-effects model for meta-analysis.ResultsEight studies involving 810 patients were included. The overall risk of bias was moderate. Seven of 8 studies used a visual analog scale to measure pain intensity. Compared with controls, intracanal cryotherapy significantly reduced postoperative pain at 6 (mean difference = −1.37; 95% confidence interval [CI], −0.61 to −2.14; P < .05; I² = 76%; moderate-quality evidence) and 24 hours after the procedure (mean difference = −1.43; 95% confidence interval, −0.70 to −2.15; P < .05; I² = 89%; moderate-quality evidence). There was no significant effect on pain at 48 and 72 hours and 7 days after the procedure.ConclusionsModerate-quality evidence suggests that intracanal cryotherapy (ie, using cold saline irrigation as a final irrigant) significantly reduces the intensity of pain at 6 and 24 hours after root canal therapy. Future clinical trials assessing the effectiveness of intracanal cryotherapy are advocated.     

Effect of Preoperative Corticosteroids in Patients with Symptomatic Pulpitis on Postoperative Pain after Single-visit Root Canal Treatment: A Systematic Review and Meta-analysis

Introduction

This study addressed the following population, intervention, comparator, outcome, timing, study design and setting question: in patients with preoperative pain who undergo single-visit nonsurgical endodontic treatment, what is the comparative efficacy of corticosteroids compared with other analgesics or placebo in reducing postoperative pain and the incidence of adverse events.

两种根充材料治疗乳牙感染根管的临床疗效评价

目的:观察新型注射式根管糊剂作为乳牙根管充填材料的疗效.方法:设碘仿氧化锌丁香油糊剂作为对照组,共对224个乳牙行根管治疗观察3个月、1年后的疗效.结果:注射式新型根管糊剂与碘仿氧化锌丁香油糊剂远期疗效有显著差异(t=0.025,P＜0.05),尤其在乳磨牙治疗效果更为显著(t=0.02,P＜0.05);实验组超充和适充疗效无显著性差异(X2=0.28,P＞0.05),与欠充之间有显著性差异(X2=6.04,P＜0.05).结论:新型注射式根管糊剂更适合临床作为常规乳牙根管充填材料.     

Root Canal Treatment and Apical Periodontitis in a Brazilian Population with Type 1 Diabetes Mellitus: A Cross-sectional Paired Study

IntroductionThis study radiographically analyzed the prevalence of root canal treatment (RCT) and apical periodontitis (AP) in type 1 diabetes mellitus (T1DM) and nondiabetic individuals and its association with the history/current status of T1DM.MethodsIn a cross-sectional paired study, the radiographic records of 50 individuals with T1DM and 100 age- and sex-matched nondiabetic subjects were examined. The presence of RCT and AP was evaluated. Information regarding the history and current status of T1DM was collected from the medical records of each patient.ResultsOne or more RCTs were found in 76% and 44% of diabetic and nondiabetic subjects, respectively (P = .000). AP in 1 or more teeth was found in most T1DM patients (58%) and in 15% of the control subjects (P = .000). One or more RCTs associated with AP were found in 52% and 8% of T1DM and nondiabetic subjects, respectively (P = .000). Bivariate logistic regression analyses suggested that RCT (odds ratio [OR] = 10.435, P = .000), AP (OR = 3.508, P = .011), and RCT + AP (OR = 7.220, P = .000) were significantly associated with the presence of T1DM. Multivariate logistic regression showed that among T1DM individuals, there is an association between 11–15 years of diagnosis time and at least 1 RCT (OR = 46.316, P = .038) and an association between T1DM control and at least 1 tooth with AP (OR = 15.611, P = .016).ConclusionsRCT, AP, and RCT with AP were more prevalent in individuals with T1DM than in nondiabetic individuals. RCT and AP were associated with the presence of T1DM, specifically RCT with diagnostic time and AP with glycemic control.     

Prevalence of Periapical Abscesses in Patients with Hypertension: A Cross-sectional Study of a Large Hospital Population

IntroductionHypertension is a common major systemic disease and 1 of the most significant causes of mortality worldwide. Persistent hypertension is 1 of the risk factors for stroke, heart attack, heart failure, and arterial aneurysm and is a leading cause of chronic kidney failure. Common medications used to treat hypertension include beta blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and calcium channel blockers. The purpose of this study was to assess the prevalence of periapical abscesses in patients with different types of hypertension conditions and to evaluate the effect of commonly used antihypertensive medications on the prevalence of periapical abscesses.MethodsThe integrated data of hospital patients were used. Data from the corresponding diagnosis codes for hypertensive conditions and periapical abscess were retrieved by searching the appropriate query in the database. The odds ratio (OR) of periapical abscesses, its association with hypertensive conditions, and the intake of 4 antihypertensive medications were calculated and analyzed statistically.ResultsThe prevalence of periapical abscesses in patients with hypertensive conditions was 1.2% compared with 0.558% in the general patient population of the hospital. The OR for the prevalence of periapical lesions in patients with hypertension was 2.32. For primary hypertension, the OR was 2.02; for hypertensive heart disease, the OR was 2.68; for hypertensive chronic kidney disease, the OR was 2.1; for hypertensive heart and chronic kidney diseases, the OR was 4.16; for secondary hypertension, the OR was 4.16; and for hypertension crisis, the OR was 5.64. For patients treated with beta blockers, the OR was 2.58; for patients treated with angiotensin-converting enzyme inhibitors, the OR was 2.73; for patients treated with angiotensin II receptor blockers, the OR was 1.93; and for patients treated with calcium channel blockers, the OR was 2.79. The differences were statistically significant (P < .0001). The OR for the prevalence of periapical abscesses in patients treated with angiotensin II receptor blockers was significantly lower than that of patients treated with either beta blockers or calcium channel blockers (P < .00001).ConclusionsUnder the conditions of this study, it appears that the prevalence of perapical abscesses is significantly higher in hypertensive patients. The prevalence of periapical abscesses is higher in patients with secondary hypertension than in those with primary hypertension. Angiotensin II receptor blockers may significantly lower the prevalence of periapical abscesses in hypertensive patients.     

Efficacy and Safety of Oral Premedication on Pain after Nonsurgical Root Canal Treatment: A Systematic Review and Network Meta-analysis of Randomized Controlled Trials

Introduction

This review aimed to find the most effective oral premedication in reducing pain in adults after nonsurgical root canal therapy (NSRCT) using network meta-analysis.

Calcium Hydroxide–Based Root Canal Sealers: A Review

The aim of this review was to consider laboratory experiments and clinical studies of calcium hydroxide–based root canal sealers. An extensive search of the endodontic literature was made to identify publications related to calcium hydroxide–based root canal sealers. The articles were assessed for the outcome of laboratory and clinical studies on their biological properties and physical characteristics. Comparative studies with other sealers were also considered. Several studies were evaluated covering different properties of calcium hydroxide–based sealers including physical properties, biocompatibility, leakage, adhesion, solubility, antibacterial properties, and periapical healing effect. Calcium hydroxide–based root canal sealers have a variety of physical and biological properties. Comparative studies reveal their mild cytotoxicity, but their antibacterial effects are variable. Further research is required to establish the tissue healing properties of calcium hydroxide in root canal sealers.     

Worldwide Assessment of the Mandibular First Molar Second Distal Root and Root Canal: A Cross-sectional Study with Meta-analysis

IntroductionThis study assessed the prevalence of radix entomolaris and 2 canals at the distal aspect of mandibular first molars among different geographic regions by means of cone-beam computed tomographic imaging.MethodsPrecalibrated observers from 23 worldwide geographic locations followed a standardized screening protocol to assess 5750 cone-beam computed tomographic images of mandibular first molars (250 per region), gathering demographic data and recording the presence of radix entomolaris and a second canal at the distal aspect of teeth. Intra- and interrater reliability tests were conducted and comparisons among groups were performed using proportions and odds ratio forest plots. The significance level was set at 5%.ResultsThe results of intra- and interrater tests were above 0.79. The prevalence of radix entomolaris varied from 0.9% in Venezuela (95% confidence interval [CI], 0%–1.9%) to 22.4% in China (95% CI, 17.2%–27.6%). Regarding the proportion of a second distal canal, it ranged from 16.4% in Venezuela (95% CI, 11.8%–21.0%) to 60.0% in Egypt (95% CI, 53.9%–66.1%). The East Asia subgroup was associated with a significantly higher prevalence of an extra distolingual root, whereas the American subgroup, the American native ethnic group, and elderly patients were linked to significantly lower percentages of a second canal at the distal aspect of teeth. No significant differences were noted between male or female patients.ConclusionsThe overall worldwide prevalence rates of radix entomolaris and a second canal at the distal aspect of the mandibular first molar were 5.6% and 36.9%, respectively. The East Asia geographic region and Asian ethnic group had a higher prevalence of a second distal root.     

Area and 3-dimensional Volumetric Changes of Periapical Lesions after Root Canal Treatments

Introduction

This study compared the changes in size of periapical lesions after root canal treatment as revealed by periapical radiography (PA) and cone-beam computed tomography (CBCT) imaging using area and 3-dimensional volumetric measurements and assessed the outcome of the treatments based on these parameters.

Methods

Both PA and CBCT scans were taken preoperatively and at recall. In total, 50 teeth (71 roots) with evidence of periapical bone loss on both PA and CBCT images were endodontically treated and followed for 10–37 months. The area and volume of periapical lesions were measured, and changes were presented in the following 4 categories: lesion undetected, lesion reduced in size, lesion unchanged, or lesion enlarged. The McNemar and chi-square tests were used to compare the lesion changes determined by CBCT imaging and PA.

Results

The 4-category diagnosis made using both methods were in agreement in 39 of 71 (54.9%) roots, whereas disagreement was observed in 32 of 71 (45.1%) roots (P < .001). At recall, lesion was absent in 11 of 71 (15.5%) roots on CBCT scans and 32 of 71 (45.1%) roots on PA (P < .001). When success was defined as the absence of a lesion or a reduction in size of a lesion, 55 (77.5%) roots on CBCT imaging showed success and 63 (88.7%) roots on PA (P = .073).

Conclusions

Changes in lesion size after root canal treatment determined with 3-dimensional volumetric CBCT data and 2-dimensional PA data are different. The outcome of root canal treatments determined with PA could be untrue.