Dentinal tubule penetration following ultrasonic, sonic, and single-cone technique of a biosealer: An ex vivo study

Background

The endodontic space is complex, and using a single-cone obturation technique fails to ensure a complete filling.

Introduction

This study aimed to investigate the effect of ultrasonic activation, sonic activation, and single-cone technique of a biosealer on its dentinal tubular penetration.

Materials and Methods

In the experiment, single-root mandibular premolars were randomly assigned to three groups (n = 20): group A, ultrasonic activation; Group B, sonic activation; and Group C, single-cone technique. Penetration of the fluorescently labeled biosealer was investigated using a confocal laser scanning microscope.

Results

The data were statistically analyzed using Kruskal-Wallis and Mann-Whitney tests (P = 0.05). The highest penetration of biosealer was observed in Group A, followed by Group B (P < 0.05).

Conclusions

Dentinal tubule penetration of biosealer was significantly improved by ultrasonic and sonic activation techniques.

The incidence of dental fractures in the Italian population during the COVID-19 pandemic: An observational study

Background

The COVID-19 infection has become a pandemic after breaking out in China in the past months of 2019 and spreading rapidly worldwide. To counter this pandemic, several governments worldwide have taken several drastic measures to try to stop the spread of the virus, including a very strict lockdown that has caused a sudden and, in many cases, negative change in people's daily lives. In the literature, several studies have shown how the pandemic has significantly impaired many people's mental health, causing short- and long-term stress, anxiety, and sleep disturbances.

Introduction

This study aims to analyze the correlation between the stress caused by the COVID-19 pandemic and the parafunctions of the temporomandibular joint and masticatory muscles, which in turn, have led to an increase in the incidence of fractures and dental injuries. The ultimate goal is to understand the best choice the dentist must make in the preventive and therapeutic fields.

Materials and Methods

A questionnaire called "Incidence of tooth fractures during the COVID-19 pandemic" was prepared using the Google® Forms platform. This questionnaire consists of 13 questions. This electronic questionnaire was addressed to all dentists in the Campania Region (ITA) and disseminated through social networks such as WhatsApp® or Facebook® or E-mail.

Results

A total of 730 dentists completed the survey. Of these, 450 (61.7%) stated that the number of patients reporting muscle and joint pain in the morning had increased during the COVID-19 pandemic. 414 (56.7%) dentists noted an increase in parafunction and 392 (53.6%) an increase in dental fractures during the pandemic period.

Discussion and Conclusions

As can be seen from the study results, an important correlation was found between the stress resulting from the COVID-19 pandemic and dental fractures. The dental elements treated endodontically, depending on the extent of the damage, require restoration, which is also the best preventive strategy in the case of dental fractures.

RETRACTED: Iandolo et al. Traditional and Recent Root Canal Irrigation Methods and Their Effectiveness: A Review. Clin. Pract. 2023, 13, 1059-1072

The Clinics and Practice Editorial Office retracts the article titled "Traditional and Recent Root Canal Irrigation Methods and Their Effectiveness: A Review" [...].

Nanoparticles and Their Antibacterial Application in Endodontics

Root canal treatment represents a significant challenge as current cleaning and disinfection methodologies fail to remove persistent bacterial biofilms within the intricate anatomical structures. Recently, the field of nanotechnology has emerged as a promising frontier with numerous biomedical applications. Among the most notable contributions of nanotechnology are nanoparticles, which possess antimicrobial, antifungal, and antiviral properties. Nanoparticles cause the destructuring of bacterial walls, increasing the permeability of the cell membrane, stimulating the generation of reactive oxygen species, and interrupting the replication of deoxyribonucleic acid through the controlled release of ions. Thus, they could revolutionize endodontics, obtaining superior results and guaranteeing a promising short- and long-term prognosis. Therefore, chitosan, silver, graphene, poly(lactic) co-glycolic acid, bioactive glass, mesoporous calcium silicate, hydroxyapatite, zirconia, glucose oxidase magnetic, copper, and zinc oxide nanoparticles in endodontic therapy have been investigated in the present review. The diversified antimicrobial mechanisms of action, the numerous applications, and the high degree of clinical safety could encourage the scientific community to adopt nanoparticles as potential drugs for the treatment of endodontic diseases, overcoming the limitations related to antibiotic resistance and eradication of the biofilm.

Child dental neglect and legal protections: a compendium of briefs from policy reviews in 26 countries and a special administrative region of China

Background

Child neglect is a public health, human rights, and social problem, with potentially devastating and costly consequences. The aim of this study was to: (1) summarize the oral health profile of children across the globe; (2) provide a brief overview of legal instruments that can offer children protection from dental neglect; and (3) discuss the effectiveness of these legal instruments.

Methods

We summarized and highlighted the caries profile and status of implementation of legislation on child dental neglect for 26 countries representing the World Health Organization regions: five countries in Africa (Nigeria, South Africa, Sudan, Tanzania, Zimbabwe), eight in the Americas (Argentina, Brazil, Canada, Chile, Mexico, Peru, Unites States of America, Uruguay), six in the Eastern Mediterranean (Egypt, Iran, Libya, Jordan, Qatar, Saudi Arabia), four in Europe (Italy, Latvia, Serbia, United Kingdom), two in South-East Asia (India and Indonesia) and one country (China) with its special administrative region (Hong Kong) in the Western Pacific.

Results

Twenty-five of the 26 countries have legal instruments to address child neglect. Only two (8.0%) of these 25 countries had specific legal instruments on child dental neglect. Although child neglect laws can be interpreted to establish a case of child dental neglect, the latter may be difficult to establish in countries where governments have not addressed barriers that limit children's access to oral healthcare. Where there are specific legal instruments to address child dental neglect, a supportive social ecosystem has also been built to facilitate children's access to oral healthcare. A supportive legal environment, however, does not seem to confer extra protection against risks for untreated dental caries.

Conclusions

The institution of specific country-level legislation on child dental neglect may not significantly reduce the national prevalence of untreated caries in children. It, however, increases the prospect for building a social ecosystem that may reduce the risk of untreated caries at the individual level. Social ecosystems to mitigate child dental neglect can be built when there is specific legislation against child dental neglect. It may be more effective to combine public health and human rights-based approaches, inclusive of an efficient criminal justice system to deal with child dental neglect.

Recent Advances in Endodontic Diagnosis and Modern Treatment Plans

Generally, to achieve success in endodontics, it is essential to perform all stages of treatment with cautiousness and excellence [...].

Traditional and Recent Root Canal Irrigation Methods and Their Effectiveness: A Review

According to contemporary dental standards, the primary goal of endodontic therapy is the chemo-mechanical cleaning of the complex root canal system. Watering root canals with approved solutions and activating them are essential parts of this operation. This review outlines various irrigant activation methods for root canal therapy. Specifically, a comparison among the methods of manual dynamic activation, sonics (subsonic, sonic, and ultrasonic), internal heating, and lasers, was conducted. The results in this work were gathered using Scopus, Web of Science, Google Scholar, and PubMed databases by searching the following keywords: sodium hypochlorite, cleaning, activation, and irrigation methods. The present work concluded that the use of irrigant activation has a greater benefit than its absence. Regardless, it is impossible to point to a single effective activation method.

Contemporary Endodontic Approaches for Children

Endodontic therapy is necessary when caries extend further into the tissues of the tooth and reach the pulp, producing irreparable inflammation or necrosis [...].

Modern Advances in Microendodontics: The State of the Art

The concept of "minimally invasive" advances is becoming increasingly popular in the endodontic field [...].

Histological Evaluation of Root Canals by Performing a New Cleaning Protocol “RUA” in Endodontic Surgery

Aim: To enhance cleaning during retro-preparation in endodontic microsurgery. Materials and Methods: Forty mandibular premolars were instrumented, filled with a single cone technique, and then retro-preparation was performed and assigned to experiment A. In group A1, the cavity created by the retro preparation was cleansed with 2 mL of normal sterile saline. In group A2, the retro cavity was cleaned with 2 mL of sterile saline after the retro preparation. All the irrigation solutions mentioned above were delivered using an endodontic needle with a lateral vent and a gauge of 30. Subsequently, in group A2, 17% EDTA gel and 5.25% gel were inserted into the cavity and activated using ultrasonic tips. After the irrigation protocols, the specimens were decalcified for histological evaluation. Results: In the experiment, the amount of hard tissue debris was significantly greater in group A1 compared to group A2 (p < 0.05). Conclusions: The samples in group A2, where the new protocol was performed, showed statistically significant results.

The Endodontic Space

Modern endodontics allows for the use of new materials and techniques in treating and saving teeth in a simple and reproducible way [...].

Smear Layer and Debris Removal from Root Canals Comparing Traditional Syringe Irrigation and 3D Cleaning: An Ex Vivo Study

Background: Endodontic treatment objectives comprise eliminating or decreasing bacterial load inside the complex endodontic space. Removing the smear layer and debris becomes mandatory to achieve good three-dimensional (3D) cleaning. Aim: This study assesses the difference in smear layer removal using the 3D cleaning technique and traditional syringe needle irrigation. The 3D cleaning technique includes the ultrasonic activation of intracanal-heated NaOCl. Materials and Methods: Our current study used single-rooted human mandibular premolar teeth to test the earlier-mentioned technique (n = 30). Initially, an endodontic access cavity was performed. Consequently, specimens were randomly distributed into three study groups according to irrigation protocol. The groups were Group 1, where the traditional syringe needle irrigation system was applied; Group 2, where the 3D cleaning technique was performed; and Group 3, in which teeth remained uncleaned as it was regarded as the control group. Once the experiment was completed, the teeth were decoronated at the cementoenamel junction (CEJ) and examined using scanning electron microscopy (SEM). Debris and smear layers were viewed in 1000× magnification and scored. Results: Statistical analysis was performed with a standard statistical software package (SPSS, version 28.0; SPSS IBM, Armonk, NY, USA). Data were analyzed with a nonparametric analysis of variance (Kruskal−Wallis ANOVA) among the groups tested and among the thirds of the canals. The level of significance was set at p < 0.05. A statistically significant (p < 0.05) lower mean smear layer and debris score was observed in both study groups compared to the control group. Group 2 showed better results compared to Group 1. Conclusions: The present study concluded that the 3D cleaning technique is an effective irrigation method for removing debris and smear layers. Future research, such as CLSM (Confocal Laser Scanning Microscopy) and Histological study, should be employed to confirm this study’s conclusion.

Modern Endodontics

The goal of modern endodontics is the complete removal of damaged tissue and bacteria from the endodontic space [...].

Prevalence, Features and Degree of Association of Oral Lesions in COVID-19: A Systematic Review of Systematic Reviews

Regardless of rapidly emerging findings on oral lesions described in adult SARS-CoV-2-positive subjects, the evidence level remains quite low and rather contrasting; therefore, the present systematic review of systematic reviews primarily aims to point out the overall prevalence of diagnosed cases. Secondary aims are to estimate the degree of association between oral lesions and SARS-CoV-2 infection and to grade, based on the reported frequency, the primary oral lesions, with related clinical presentations and microscopic features, in relation to COVID-19 forms. A study protocol compliant with the PRISMA statement was developed. Twelve studies were included, reporting highly heterogeneous and incomplete findings, thus precluding a meta-analysis. Further studies should be conducted to assess the overall prevalence of cases diagnosed with oral lesions among adult SARS-CoV-2-positive subjects, especially considering novel viral variants, and to determine their degree of association with SARS-CoV-2 infection and COVID-19 forms. Moreover, the reported findings noticed the need to evaluate the putative role both of SARS-CoV-2 in oral lesions genesis and of periodontitis and periodontal microbiome in COVID-19 worsening and re-activations. Deeper insights into oral lesions in adult SARS-CoV-2-positive subjects could enhance the comprehension of illness pathogenesis, natural history and clinical presentation, thus improving the preparedness of health professionals in the inter-disciplinary management of COVID-19.

Periodontal and Peri-Implant Health Status in Traditional vs. Heat-Not-Burn Tobacco and Electronic Cigarettes Smokers: A Systematic Review

The aim of the present systematic review was to evaluate and possibly differentiate the effects of traditional cigarettes, heat-not-burn tobacco, and electronic cigarettes on periodontal and peri-implant health status. Electronic cigarettes and heat-not-burn tobacco have become very popular in recent years and have been proposed to consumers as a safer alternative to conventional tobacco smoke, although their effect on periodontal and peri-implant health remains unclear. The study protocol was developed according to PRISMA guidelines, and the focus question was formulated according to the PICO strategy. A literature search was conducted across PubMed/MEDLINE and the COCHRANE library from 2003 to April 2022. From the 1935 titles initially identified, 18 articles were finally included in the study and extracted data were qualitatively synthesized. It may be carefully concluded that e-cigarettes may cause attenuated clinical inflammatory signs of periodontitis and, hypothetically, of peri-implantitis when compared to conventional tobacco smoke. Both alternative smoking products, containing nicotine, may likewise exert negative effects on periodontal and peri-implant health, as demonstrated by in vitro studies. Further investigations are needed to assess the impact of electronic cigarettes and heat-not-burn tobacco products on periodontal and peri-implant health status.

Chronic Stress and Depression in Periodontitis and Peri-Implantitis: A Narrative Review on Neurobiological, Neurobehavioral and Immune-Microbiome Interplays and Clinical Management Implications

Besides the well-known systemic factors for periodontal and peri-implant diseases, additional co-factors, such as chronic stress and depression, may also affect disease onset and progression as well as treatment responsiveness. Neurobiological and neurobehavioral pathogenic links between chronic stress and depression, on the one side, and periodontitis and peri-implantitis, on the other side, which have been little investigated and principally related to necrotizing periodontal disease, have been reviewed, along with their putative interconnections with periodontal immune-microbiome balance. Rising evidence suggest that dysregulated neurobiological and neurobehavioral factors, as well as periodontal immune-microbiome unbalance, all related to chronic stress and depression, may crucially interact and thus represent contributing factors in the genesis and worsening not only of necrotizing periodontal lesions, but also of chronic periodontitis and peri-implantitis. Such potential interconnections may be even more relevant in recurrent and aggressive cases of periodontal and peri-implant disease, which are frequently refractory to therapy, and may, if corroborated, coherently pave the way for personalized prevention and treatment strategies, possibly targeting immune-microbiome unbalance and neurobehavioral factors and focusing on neurobiological ones, especially in chronically stressed and depressed subjects with periodontitis and peri-implantitis.

Effect of hepatitis C antiviral therapy on oral lichen planus and hyposalivation in inmates

Background

Oral lichen planus (OLP) and hyposalivation have been reported as extrahepatic manifestations of hepatitis C virus (HCV) infection. Our study evaluated the effect of direct antiviral agents (DAAs) on OLP and hyposalivation in convicts with chronic hepatitis C, examining patients before, during and after the antiviral treatment period with direct acting antiviral agents (DAAs).

Methods

We screened 198 inmates for the presence of the HCV antibody. Patients found to be positive underwent a quantitative HCV-RNA test and HCV genotype typing, as well as an oral cavity examination using a scoring system for OLP (REU score) and the clinical oral dryness score (CODS). Subsequently, all patients underwent DAA therapy and a systematic physical examination of the oral cavity at 1, 3 and 6 months from the beginning of treatment.

Results

Fifty patients (25.25%) had a positive HCV-RNA test. At baseline, OLP was detected in 4 patients (8%), with a mean REU score of 10.13±4, and different degrees of hyposalivation were seen in 17 patients (34%), with a mean CODS score of 4.71±1.72. Six months after the start of DAA therapy, we observed resolution of OLP in 3 patients (75%) and improvement in the remaining subject with a significantly lower mean REU score (2±4). Hyposalivation disappeared in 5 patients, improved in 10, and remained unchanged in 2 patients with a significantly lower mean CODS score (0.06±0.24).

Conclusion

This study demonstrated the effectiveness of DAAs in the treatment of OLP and hyposalivation.

Modern rotary files in minimally invasive endodontics: a case report

Modern Endodontics aims to remove or decrease the bacterial load within the endodontic space. This target is achieved by performing adequate mechanical preparation combined with three-dimensional cleaning. The first step, shaping, is done using manual stainless steel files and Ni-Ti rotating files. In recent years, new rotating files have been developed in the martensitic phase, which, being more flexible, guarantees to work safely in the case of difficult anatomies. Therefore, this study aimed to demonstrate a non-surgical endodontic treatment using modern Ni-Ti files in a minimally invasive approach.

Confocal laser scanning microscopy evaluation of roots subjected to activation protocol in endodontic microsurgery

This study evaluated the penetration of the irrigant subject to activation after performing retro-preparation in endodontic microsurgery. Forty mandibular premolars were prepared and filled. Subsequently, 1 mm from the root apex was cut using a multi-blade bur and the retro-preparation was performed. In group 1, the retro-cavity was cleaned with 2 mL of saline and then with 2 mL of 5.25% NaOCl gel mixed with 0.1% Rhodamine B. In group 2, the retro-cavity was cleaned with 2 mL of saline, 17% EDTA gel was activated ultrasonically for 30 s and 5.25% NaOCl gel was mixed with 0.1% Rhodamine B and activated for 30 s. After 7 days, the roots were cut at 1mm from the apex and the slices were evaluated with confocal laser scanning microscopy. The samples of group 2 showed statistically better results. The activation protocol proposed resulted in enhanced irrigant penetration when compared to the traditional.

Riga-Fede disease: A systematic review and report of two cases

AIM

The term Riga-Fede disease has been used historically to describe traumatic ulceration that occurs on the ventral surface of tongue, buccal mucosa, gum or floor of the tongue in newborns and infants. It is most often associated with natal and neonatal teeth in newborns. The painful symptoms may be absent or acute, up to the point of preventing the baby from feeding. The aim of this work is to offer a description of the therapeutic solutions for the treatment of this pathological condition, with a review of the literature and the report of two cases.

MATERIALS

A systematic review of the literature of articles presenting Riga-Fede Disease associated with natal and neonatal teeth was performed following the PRISMA protocol (Prefered Reporting Items for Systematic Reviews and Meta-Analyses). This bibliographic search was performed through two databases, PubMed and Google Scholar.

CONCLUSION

Extraction and ameloplasty are the most effective treatments in the resolution of the Riga-Fede disease associated with natal/neonatal teeth. In the case of high dental mobility, resulting in an increased risk of exfoliation and possible tooth ingestion/inhalation, extraction is the therapeutic treatment of choice. When nutrition is not compromised, ameloplasty is the treatment of choice, as it is less invasive and more conservative.

COVID-19: The Patients' Perceived Impact on Dental Care

Objectives  The present study aims to investigate the effect of the COVID-19 pandemic on people's mental and physical balance, oral hygiene habits, type of diet, perceived safety of returning to the dentist, and aesthetics with the use of masks.

Materials and Methods  An online questionnaire was submitted to the Italian population between December 2020 and January 2021. It was sent via online platforms and included 21 questions.

Statistical Analysis  Differences in rates were calculated by using the Chi-square test. The level of significance was set at p <0.05.

Results  A total of 1,008 individuals completed the questionnaire. About 72% of participants were not concerned about returning to the dentist. Approximately 45% of the individuals intensified their oral hygiene and preventive rules. About 38% of participants increased their carbohydrate intake, while 28% increased their fat consumption. Furthermore, 75% of the participants felt that the mask did not diminish the beauty of their smile.

Conclusions  Most participants felt comfortable returning to the dentist but only for more urgent treatment. However, most people reported that they had not stepped up their home oral hygiene measures. The biggest changes in the population's eating habits involved increased carbohydrate and fat consumption. Finally, most participants responded that mask use did not compromise their aesthetics.

An innovative technique to safely perform active cleaning in teeth with open apices: CAB technique

The current study aims to evaluate in vitro the extrusion of NaOCl, using an artificial root canal with an open apex, using different canal irrigation protocols. For this study, a transparent artificial root canal was used. The apex was shaped to be oversized and irregular in form. After root canal mechanical shaping, the artificial cylindrical chamber, which was made below the large apical foramen, was filled with fuchsine-stained bovine pulp tissue. Afterward, irrigation protocols were carried out and compared regarding their safety with regards to irrigant extrusion. Subsequently, the examiner created two groups, Group A: internal heating associated with ultrasonic activation and Group B: internal heating associated with ultrasonic activation, using the CAB technique. In both the groups, 5.25% sodium hypochlorite solution was used as the irrigant. Regarding assessing the presence or absence of the extrusion, photographs at ×20 were taken and analyzed. For the statistical analysis, a t-test for paired samples was used. Extrusion of irrigant beyond the apex was present only in Group A. The main objective of endodontic treatment is the removal of damaged tissues and bacteria. For this reason, active cleaning is crucial in all endodontic treatment cases. Internal heating followed with ultrasonic activation while using the CAB technique was an effective and safe technique to ensure no irrigant extrusion beyond the open apex.

Systematic Review on White Spot Lesions Treatments

The difference in refractive index between the healthy enamel and the demineralized area generates a lesion with a milky white opaque appearance, clearly distinguishable from the surrounding healthy enamel. The aim of this systematic review was to evaluate if the infiltration technique is the most efficient treatment to resolve a white spot lesion when compared with remineralization and microabrasion techniques. The Population/Intervention/Comparison/Outcome question investigated: “in enamel WS lesion, the infiltration treatment compared to remineralization or microabrasion treatments is more or less effective in the camouflage effect?.” The research was performed on electronic databases, including Ovid MEDLINE, PubMed, and web of science. The search was conducted up to April 1, 2020. The scientific search engines produced 324 results. Only 14 were screened after screening. Based on the articles analyzed in this systematic review, the resin infiltration technique seems to be the most effective and predictable treatment for the aesthetic resolution of WSLs.

Use of Diode Laser for Surgical Removal of Pyogenic Granuloma of the Lower Lip in a Pediatric Patient: A Case Report

BACKGROUND A pyogenic granuloma is an inflammatory exophytic lesion that can occur in the oral cavity. Numerous factors are involved in the etiology of the lesion and can lead to the tissue proliferation underlying the lesion's characteristic appearance. The main treatment is surgical excision with careful curettage of the surrounding tissues. The use of a laser has been proposed because it enables performing deep and precise incisions with better hemostasis and less invasive procedures with less discomfort to patients. The aim of this study was to evaluate the possible advantages of using a diode laser in the surgical treatment of pyogenic granuloma, particularly in the management of a pediatric patient. CASE REPORT A swelling in the lower lip of an 11-year-old female patient was analyzed. After several evaluations, a 980-nm diode laser in continuous wave mode was chosen for excision of the lesion. The lesion was excised successfully with a diode laser as a conservative method that was nonstressful for the pediatric patient. CONCLUSIONS Among the techniques for surgical excision of a lesion, the use of a diode laser has the following advantages: less invasiveness, absence of intra- and postoperative discomfort and pain, effective hemostasis with better control of bleeding, absence of scarring, better postoperative management, and greater patient compliance.

Conservative shaping combined with three-dimensional cleaning can be a powerful tool: Case series

Conservative endodontics has been introduced about a decade ago. Since then, it has been demonstrated that less canal preparations lead to more dentin preservation resulted in decreased stress on tooth structure, mainly in the coronal third of the root, and potentially a higher resistance to fracture. In addition, smaller and larger canal preparations were comparable with regard to the cleanliness of the root canal. The purpose of this case series was to report on the outcome of root canal treatments following a conservative canal preparation, followed by three-dimensional cleaning technique (intracanal heating and ultrasonic activation of NaOCl).

Effect of different final irrigation protocols on pulp tissue dissolution from an isthmus model

This study assessed the pulp tissue dissolution from isthmus of a two-rooted maxillary premolar using different final irrigation protocols. After root canal preparation, the surface of the tooth was reduced to an extent that the isthmus could be observed, and 1 mg of pulp tissue was introduced into the isthmus which was covered with a glass slide. Following six groups were tested: syringe and needle; subsonic activation; sonic activation; ultrasonic activation; heating followed by sonic activation; and heating followed by ultrasonic activation. Before and after each experiment a photograph of the isthmus was taken at 30× to register the area of the pulp tissue. Statistical analysis was performed with Kruskal-Wallis and Mann-Whitney tests (P < 0.05). Syringe and needle group showed the lower value of pulp tissue dissolution followed by subsonic irrigation procedures. Pulp tissue dissolution was significantly higher when heating was followed by sonic or ultrasonic activation.

The perception of COVID-19 among Italian dental patients: an orthodontic point of view

BACKGROUND

The present study aimed to investigate the patients' perception of the dental practice during the COVID-19 outbreak, and whether the pandemic will affect the attendance of orthodontic patients at the dental practice. An online questionnaire, including the Patient Health Questionnaire-4 (PHQ-4), was submitted to Italian dental patients with items about their perceived risks when going to the dentist, concerns about continuing orthodontic treatment, and the onset of temporomandibular disorders (TMD). Data were analyzed with a chi-square test and logistic regression analysis. The level of significance was set at P < 0.05.

RESULTS

A total of 1566 subjects completed the survey, including 486 who were under orthodontic treatment or who had a child in orthodontic treatment. A total of 866 participants (55.3%) thought the risk of contracting the COVID-19 infection was higher in a dental practice; this perception was associated with gender (women more than man), age (over 60 years old) and high levels of distress (P<0.001). However, 894 patients (57.1%) felt comfortable going back to the dentist. Most of the orthodontic patients (84%) would continue their treatment. After the lockdown, there was a slight increase in the frequency of TMD pain (356 versus 334).

CONCLUSIONS

Most of the participants believed that the dental practice is a place at greater risk of contracting COVID-19, even if they continue to go to the dentist. Gender, age, and the level of distress were associated with the increase in the fear of going to the dentist due to COVID-19. Because of the pandemic, 16% of patients undergoing orthodontic treatment would not return to the dental practice to continue their orthodontic treatment after the lockdown. The prevalence of TMD pain in the population increased due to the pandemic.

Perceived Preparedness of Dental Academic Institutions to Cope with the COVID-19 Pandemic: A Multi-Country Survey

Dental academic institutions are affected by COVID-19. We assessed the perceived COVID-19 preparedness of these institutions and the characteristics of institutions with greater perceived preparedness. An international cross-sectional survey of dental academics was conducted from March to August 2020 to assess academics’ and institutional attributes, perceived preparedness, and availability of infection prevention and control (IPC) equipment. Principal component analysis (PCA) identified perceived preparedness components. Multilevel linear regression analysis assessed the association between perceived preparedness and fixed effect factors (academics’ and institutions’ attributes) with countries as random effect variable. Of the 1820 dental academics from 28 countries, 78.4% worked in public institutions and 75.2% reported temporary closure. PCA showed five components: clinic apparel, measures before and after patient care, institutional policies, and availability of IPC equipment. Significantly less perceived preparedness was reported in lower-middle income (LMICs) (B = −1.31, p = 0.006) and upper-middle income (UMICs) (B = −0.98, p = 0.02) countries than in high-income countries (HICs), in teaching only (B = −0.55, p < 0.0001) and in research only (B = −1.22, p = 0.003) than teaching and research institutions and in institutions receiving ≤100 patients daily than those receiving >100 patients (B = −0.38, p < 0.0001). More perceived preparedness was reported by academics with administrative roles (B = 0.59, p < 0.0001). Academics from low-income countries (LICs) and LMICs reported less availability of clinic apparel, IPC equipment, measures before patient care, and institutional policies but more measures during patient care. There was greater perceived preparedness in HICs and institutions with greater involvement in teaching, research, and patient care.

A novel modified obturation technique using biosealers: An ex vivo study

Background:

The root canal anatomy is a complex space, and using a single-cone obturation technique does not guarantee a complete filling.

Aim:

This research aimed to evaluate the actual temperature of the biosealer during the obturation phase inside the root canal using a new hot technique. In addition, this study evaluated the penetration depth of the biosealer inside dentinal tubules.

Setting and Design:

The current study was concluded on two ex vivo experiments; the former tested the temperature evaluation. The latter examined the penetration depth of the biosealer.

Materials and Methods:

In this study, 42 sec mandibular premolars were used, and two experiments were carried out. In the first experiment, two premolars were utilized, and two thermocouples of K-type for each tooth were used. During the second experiment, the penetration depth of the biosealer was examined, 40 teeth were selected. Root canals were prepared then divided into two obturation groups: A, gutta-percha, and biosealer with single-cone technique and B, gutta-percha, and biosealer with a newly proposed obturation method. Confocal laser scanning was used to assess the penetration of the sealer.

Statistical Analysis Used:

In the first experiment, the Bonferroni method was performed to compare the temperature data. The tests used in the second experiment were Shapiro–Wilk's test, Kruskal–Wallis, and Mann–Whitney tests.

Results:

The first experiment results showed that the heat does not reach the apical third using the new obturation method. In the second experiment, the results showed in Group B significantly higher biosealer penetration into the dentinal tubules as compared to Group A (P < 0.05).

Conclusions:

The highest level of penetration of the biosealer in the dentinal tubules was observed in the group of the new obturation method, and the last apical 3 mm remained at 37° using this novel hot modified technique providing no risk of chemical alteration of the biosealer.

Knowledge of dental academics about the COVID-19 pandemic: a multi-country online survey

BACKGROUND

COVID-19 is a global pandemic affecting all aspects of life in all countries. We assessed COVID-19 knowledge and associated factors among dental academics in 26 countries.

METHODS

We invited dental academics to participate in a cross-sectional, multi-country, online survey from March to April 2020. The survey collected data on knowledge of COVID-19 regarding the mode of transmission, symptoms, diagnosis, treatment, protection, and dental treatment precautions as well as participants' background variables. Multilevel linear models were used to assess the association between dental academics' knowledge of COVID-19 and individual level (personal and professional) and country-level (number of COVID-19 cases/ million population) factors accounting for random variation among countries.

RESULTS

Two thousand forty-five academics participated in the survey (response rate 14.3%, with 54.7% female and 67% younger than 46 years of age). The mean (SD) knowledge percent score was 73.2 (11.2) %, and the score of knowledge of symptoms was significantly lower than the score of knowledge of diagnostic methods (53.1 and 85.4%, P <  0.0001). Knowledge score was significantly higher among those living with a partner/spouse than among those living alone (regression coefficient (B) = 0.48); higher among those with PhD degrees than among those with Bachelor of Dental Science degrees (B = 0.48); higher among those seeing 21 to 30 patients daily than among those seeing no patients (B = 0.65); and higher among those from countries with a higher number of COVID-19 cases/million population (B = 0.0007).

CONCLUSIONS

Dental academics had poorer knowledge of COVID-19 symptoms than of COVID-19 diagnostic methods. Living arrangements, academic degrees, patient load, and magnitude of the epidemic in the country were associated with COVD-19 knowledge among dental academics. Training of dental academics on COVID-19 can be designed using these findings to recruit those with the greatest need.

Behavior change due to COVID-19 among dental academics-The theory of planned behavior: Stresses, worries, training, and pandemic severity

OBJECTIVE

COVID-19 pandemic led to major life changes. We assessed the psychological impact of COVID-19 on dental academics globally and on changes in their behaviors.

METHODS

We invited dental academics to complete a cross-sectional, online survey from March to May 2020. The survey was based on the Theory of Planned Behavior (TPB). The survey collected data on participants' stress levels (using the Impact of Event Scale), attitude (fears, and worries because of COVID-19 extracted by Principal Component Analysis (PCA), perceived control (resulting from training on public health emergencies), norms (country-level COVID-19 fatality rate), and personal and professional backgrounds. We used multilevel regression models to assess the association between the study outcome variables (frequent handwashing and avoidance of crowded places) and explanatory variables (stress, attitude, perceived control and norms).

RESULTS

1862 academics from 28 countries participated in the survey (response rate = 11.3%). Of those, 53.4% were female, 32.9% were <46 years old and 9.9% had severe stress. PCA extracted three main factors: fear of infection, worries because of professional responsibilities, and worries because of restricted mobility. These factors had significant dose-dependent association with stress and were significantly associated with more frequent handwashing by dental academics (B = 0.56, 0.33, and 0.34) and avoiding crowded places (B = 0.55, 0.30, and 0.28). Low country fatality rates were significantly associated with more handwashing (B = -2.82) and avoiding crowded places (B = -6.61). Training on public health emergencies was not significantly associated with behavior change (B = -0.01 and -0.11).

CONCLUSIONS

COVID-19 had a considerable psychological impact on dental academics. There was a direct, dose-dependent association between change in behaviors and worries but no association between these changes and training on public health emergencies. More change in behaviors was associated with lower country COVID-19 fatality rates. Fears and stresses were associated with greater adoption of preventive measures against the pandemic.

Management of Severe Curvatures in Root Canal Treatment with the New Generation of Rotating Files Using a Safe and Predictable Protocol

Objective:

The aim of this work was to show the management of severe curvatures done with the new generation of rotating files through a safe and predictable protocol.

Methods:

Three clinical cases were described. A safe protocol was explained using the latest generation of rotating files for the shaping of the anatomy of complex root canals. All the cases presented 90°, 45° curvatures and/or double curvatures.

Results:

The instrumentation of canals increased their surface area and volume. All the cases with 90° and 45° curvatures were optimally shaped.

Conclusion:

With the help of rotating files in the martensitic alloy, it is possible to work safely, while avoiding the risk of file separation, even in root canals with severe curvatures, thus achieving success even in complex clinical cases.

Evaluation of the actual chlorine concentration and the required time for pulp dissolution using different sodium hypochlorite irrigating solutions

Introduction:

The goal of root canal treatment is to shape and clean the endodontic space, reducing the bacterial load and removing the pulp tissue. Obviously, the action of the endodontic instruments is limited to the main canals, regardless of the complexity of the endodontic space. Consequently, finding the best possible cleaning technique, which can be obtained chemically using irrigation solutions, is a fundamental aid in endodontic therapy. One of the most commonly used root canal irrigants is sodium hypochlorite (NaOCl), available in various commercial formulations. The effectiveness of NaOCl is undeniable. However, the action of dissolution of the pulp tissue is merely dependent on the concentration and the characteristics of the irrigant itself.

Aim:

The aim of this study is to evaluate the effective concentration of different commercial formulas of NaOCl, by evaluating the percentage of total chlorine in each product. The dissolution capacity of the pulp tissue of each of the tested products was then analyzed by measuring the required time.

Materials and Methods:

Three commercial types of NaOCl were selected for this study: 5% NaOCl (ACE, Procter and Gamble), 5% NaOCl (N5, Simit Dental), and 6% NaOCl (CanalPro, Coltene). For each product, 10 packages were used, from which samples of the product were taken and 30 ml × 5 ml tubes were filled. All samples were divided into three groups and were analyzed using the DIN EN ISO 7393-2 method and the percentage of total chlorine (expressed as a percentage) was calculated. Forty samples of vital pulp were obtained from teeth freshly extracted for periodontal reasons and stored in physiological solution. In order to unify the size and weight of the samples (0.0001 mg), a microtome and a precision balance (Pro Explorer Ohaus) were used. Each sample, carefully examined by stereomicroscope (×40), was placed in artificial plastic containers and submerged in 0.1 ml of irrigating solution at room temperature (26°C). A fourth control group used saline solution as irrigant. Simultaneously with the insertion of the irrigating solution, a digital stopwatch was activated and the time necessary for the complete dissolution of the pulp sample was measured. The data obtained was subjected to statistical analysis.

Results:

The average percentages of chlorine detected for each group were: 4.26% (ACE), 5.16% (N5), and 5.97% (CanalPro). The Kruskal–Wallis test showed statistically significant differences between the different commercial formulations of hypochlorite (P < 0.05). CanalPro showed the lowest values, whereas ACE showed the highest values of dissolution time of the pulp.

Discussion:

The analysis of the total chlorine percentage found that the actual concentration of the NaOCl in the samples is close to the values declared by the manufacturers both in the case of N5 and CanalPro. On the contrary, the concentration detected in the samples of common bench bleach (ACE) is significantly lower, which has average values <5%. This explains the longer time taken for the complete dissolution of the pulp tissue. The average dissolution time of the pulp samples was in fact inversely proportional to the concentration detected in the tested irrigants and hence that a lower time corresponds to a higher concentration.

The IG- file use to Gauge the Apical Diameter in Endodontics: An In Vitro Study

Aim:

The aim of this study was to evaluate the efficacy of the IG-file, a new instrument designed for apical diameter gauging.

Materials and Methods:

After shaping with F1 Universal Protaper, 60 roots were randomly divided into two groups and assigned to two operators, One Expert in Endodontics (EO) and One Unexpert (UO).

In each sample, after canal curvatures have been detected, the apical diameters were measured with the IG-file and the K-NiTi. The results were compared with the reference value obtained by retrograde apical gauging. The data were statistically analyzed.

Results:

Among 60 samples, 10% of errors were recorded when the IG-files were used; in the K-NiTi group the incorrect measurements were 70%.

In both groups (expert and unexpert) the IG-file measurements were more accurate than the K-NiTi (90 vs 33 and 90 vs 26,7). The differences were statistically significant.

In curved canals, the difference between measurement rates performed with both instruments was statistically significant (85,7% IG-file vs 28,6% K-NiTi) as well as for the samples without curvatures (92,3% IG file vs 30,8% NiTi file).

In root canals without curvatures overestimation errors in K-NiTi file group are more frequent than underestimation errors. This difference was statistically significant.

Conclusion:

A proper gauging of the apical diameter has a key role in endodontic therapy; an incorrect measurement can lead to clinical failures. This “in vitro” study highlights that IG-file improves measurement accuracy independently from clinician experience. Furthermore, in curved canals, the IG-file is more accurate than K-NiTi.

Thermafil: A New Clinical Approach Due to New Dimensional Evaluations

Background

There are a lot of techniques to obturate the root canals, but lateral condensation of gutta-percha is the most used one. An important aspect of thermafil is the error margin tolerated by the manufacturer in the production of plastic carriers. In literature, there is no evidence about discrepancy percentage between different carriers. It is demonstrated that the error margin of gutta-percha is 0.5% and is 0.2% for metal files (ISO standards).

Objective

The aim of this study was to evaluate the real dimensions of thermafil plastic carriers observed by the stereo microscope measuring the dimensional discrepancy between them.

Methods

For this study, 80 new thermafil (Dentsply Maillefer) have been selected. 40 thermafil 0.25 and 40 thermafil 0.30. Through 60X stereo microscope, the dimensions of the plastic carrier tips have been measured. The dimensions of the plastic carrier were also measured after a heating cycle. ZL GAL 11TUSM (Zetaline stereo evolution) microscope was used to observe the samples. Measurements were made through a dedicated software (Image Focus). All samples were analysed at 60X.

Results

A non-parametric paired test (Wilcoxon test) was used to compare baseline and after heating values; p-values ≤ 0.05 were assumed to be statistically significant.

Conclusion

The samples we measured showed a mean value of the diameters in Thermafil 25 that was 0.27 mm, for Thermafil 30 the mean value was 0.33 mm.We have measured a dimensional variable of 8% in the 25 group while in group 30 the maximum possible variation found was 4%, that's why we propose a new protocol of obturation with thermafil. We can also conclude that a single heating process does not affect clinically the plastic carrier dimensions.

Intracanal heating of sodium hypochlorite: Scanning electron microscope evaluation of root canal walls

Introduction:

The aim of this study is to evaluate the surface of root canals dentine using scanning electron microscope (SEM) after instrumentation with rotary Nickel-Titanium systems and two different protocols of activation of sodium hypochlorite (NaOCl) (extracanal heating at 50°C and intracanal heating at 180°C), to assess the presence/absence of smear layer and also the presence/absence of open dentinal tubules along the walls at the coronal, middle, and apical third of each sample.

Materials and Methods:

Thirty-six single-rooted teeth were selected, divided into three groups and shaped with ProTaper Universal instruments following irrigation protocols with 5.25% NaOCl. At the end of the preparation, three different protocols of activation were used: nonheated NaOCl in Group A, extra-canal heated NaOCl at 50°C for Group B and intracanal heated NaOCl at 180°C for Group C. Specimens were cut longitudinally and analyzed by SEM at standard magnification of ×1000. The presence/absence of the smear layer as well as the presence/absence of open tubules at the coronal, middle, and apical third of each canal were estimated using a five-step scale for scores. Numeric data were analyzed using Kruskal–Wallis and Mann–Whitney U statistical tests and significance was predetermined at P < 0.05.

Results:

Kruskal–Wallis analysis of variance (ANOVA) for debris score showed significant differences among the Ni-Ti systems (P < 0.05). Mann–Whitney test confirmed that Group A presented significantly higher score values than other Ni-Ti systems. The same results were assessed considering the smear layer scores. ANOVA confirmed that the apical third of the canal maintained a higher quantity of debris and smear layer after preparation of all the samples.

Discussion and Conclusions:

Intra-canal heating of NaOCl at 180°C proved to be more effective in obtaining clean canal walls. On the other hand, extra-canal heating at 50°C of NaOCl left a higher quantity of debris and the smear layer was widely represented.

An in vitro evaluation of the degree of pulp tissue dissolution through different root canal irrigation protocols

Aim

The aim of this study is to evaluate in vitro, using artificial lateral canals, the rate of dissolution of the pulp tissue through different protocols of canal irrigation.

Materials and Methods

One hundred artificial canals provided with lateral canals have been used. Each lateral canal was filled with pulp tissue and calibrated to 0.002 mg. All canals were irrigated using five different protocols. Five groups have been used for the experiment: Group A, distilled water (control); Group B, preheated NaOCl; Group C, NaOCl heated inside the canal; Group D, NaOCl ultrasonically activated; and Group E, NaOCl heated inside the canal with ultrasonic activation. All samples were weighed through professional microbalance in three different phases: before insertion of the pulp tissue into the lateral canal, after insertion of the pulp tissue and, finally, after different protocols of irrigation. A statistical analysis with Kruskal-Wallis test and Mann-Whitney test was performed.

Results

The partial dissolution of the pulp tissue inside the artificial lateral canal occurs only using the protocol with NaOCl heated inside the canal with ultrasonic activation. Other irrigation protocols are not able to dissolve the pulp tissue.

Discussion and Conclusions

The main objective of endodontic therapy is the removal of damaged tissues and bacteria. Modern literature highlights that it is impossible to remove all the pulp tissues and bacteria from the whole endodontic space. Hence, to achieve excellence and get positive results in the short and long term, it is necessary to use techniques and technologies that may increase the degree of root canal detersion.

Evaluation of cyclic fatigue resistance of modern Nickel-Titanium rotary instruments with continuous rotation

Aim: The aim of present study was to compare cyclic fatigue resistance of three modern Ni-Ti instruments used with continuous rotation. Materials and methods: For this study 3 groups of rotating instruments with continuous rotation (HyFlex EDM, Twisted File Adaptive, Revo S SU) have been used, each group consisted of 20 files. The various groups were subjected to cyclic fatigue testing through an artificial metal device. A statistical analysis with Kruskal-Wallis test and Mann-Whitney test was performed. Results: There were statistically significant differences between the three groups. The HyFlex EDM instruments have a fracture resistance slightly higher than the Twisted file and far higher than Revo S SU. Conclusions: Modern Ni-Ti alloys increase resistance of the rotating instruments to cyclic fatigue.