Investigação ex vivo do diâmetro anatômico do canal mesiopalatino de primeiros molares superiores humanos / Ex vivo investigation of the anatomical diameter of the mesiopalatal canal of human maxillary first molars

Objetivou-se investigar ex vivo o diâmetro anatômico e conicidade do canal mesiopalatino de primeiros molares superiores. Para tanto, trinta e três primeiros molares superiores humanos foram acessados, explorados para confirmação da existência do canal mesiopalatino, identificados, suas raízes mesiovestibulares seccionadas transversalmente em três níveis e, então, os fragmentos foram fotografados com microscópio digital, que permitiu a realização das determinações dos diâmetros anatômicos deste canal em cada amostra. Os resultados foram calculados em função dos valores médios e de desvio padrão dos diâmetros em cada nível, obtendo-se respectivamente 0,20 mm e ±0,09 mm (nível cervical), 0,20 mm e ±0,08 mm (nível médio) e 0,17 mm e ±0,06 mm (nível apical). Nas condições deste estudo, de acordo com caráter atrésico e baixa conicidade do conduto mesiopalatino, sugere-se a necessidade de uso de instrumentos de diâmetro de ponta mínimo de 0,25 mm e conicidade 0,03 para o seu preparo.

The aim was to investigate ex vivo the anatomical diameter and taper of the mesiopalatine canal of maxillary first molars. To this end, thirty-three human maxillary first molars were accessed, explored to confirm the existence of the mesiopalatine canal, identified, their mesiobuccal roots transversely sectioned at three levels and then the fragments were photographed using a digital microscope, which allowed the anatomical diameters of this canal to be determined in each sample. The results were calculated according to the mean and standard deviation values of the diameters at each level, obtaining 0.20 mm and ±0.09 mm (cervical level), 0.20 mm and ±0.08 mm (middle level) and 0.17 mm and ±0.06 mm (apical level) respectively. Under the conditions of this study, given the atresic nature and low taper of the mesiopalatine canal, it is suggested that instruments with a minimum tip diameter of 0.25 mm and a taper of 0.03 should be used for its preparation.

Análise do diâmetro de cones acessórios calibrados por réguas calibradoras / Diameter analysis of accessory cones calibrated by calibrating rulers

O objetivo do presente estudo foi de comparar o diâmetro dos cones acessórios FM EL calibrados por duas réguas calibradoras com seus respectivos diâmetros nominais. Foram calibrados 80 cones de guta percha FM EL (Odous de Deus) utilizando duas réguas calibradoras das seguintes marcas: Prisma e Denco. Os cones foram divididos em 8 grupos (n=10) de acordo com a régua e com o diâmetro em que foram calibrados. Posteriormente, os cones foram fotografados e tiveram seus D0 mensurados através do software ImageJ. Após a realização da análise estatística utilizando-se os testes de Normalidade de Shapiro-Wilk e o teste t Student (Distribuição Normal), obteve-se os seguintes resultados: não houve diferença estatisticamente significativa com o valor de referência na régua prisma nos cones 40, isto é, em todas as outras situações encontrou-se diferença com os valores de referência. Quando foram comparados os valores das medianas e desvio padrão das duas réguas calibradoras também houve diferença estatisticamente significativa (p<0,05) nos cones 25, 35 e 40. Os cones acessórios FM EL (Odous de Deus) calibrados com a régua Denco diferiram dos diâmetros nominais da régua. Assim, deve-se estar atento à exatidão e precisão desses instrumentos a fim de se evitar possíveis erros de mensuração e interpretação capazes de comprometer o êxito da obturação no tratamento endodôntico.

The aim of the present study was to compare the diameter of the FM EL accessory cones calibrated by two calibrating rulers with their respective nominal diameters 80 FM EL gutta percha cones (Odous of God) were calibrated using two calibrating culers of the following brands: Prisma and Denco. The cones were divided in 8 groups (n=10) according to the ruler and the diameter in which they were calibrated. Posteriorly, the cones were photographed and nad their D0 neasured through the software ImageJ. After performing the statistical analysis using the Shapiro- Wilk Normality tests and the Student T test (Normal Distribution), the following results were obtained: there was no stastistically significant difference with the reference value in the prism rule in the cones 40, that is, in all other situations, a difference was found with the reference values. When the median values and standard deviation of the two calibrating rulers were compared, there was also a statistically significant difference (p<0,05) in cones 25, 35 and 40. The FM EL (Odous of God) accessory cones calibrated eita the Denco ruler differed from the nominal diameters of the ruler. Thus, one must pay attention to the accuracy and precision of these instruments in order to avoid possible errors of measurement and interpretation capable of compromising the success of filling in endodontic treatment.

Percepção profissional sobre tratamento endodôntico em sessão única e múltiplas sessões / Professional perception of single and multi-session endodontic treatment

Na odontologia a decisão do tratamento é exclusiva dos cirurgiões dentistas e suas percepções, incluindo filosofia de tratamento, fazendo com que a prática de novos conceitos, tratamentos ou técnicas dependam não apenas de sua lógica ou eficácia biológica. Sendo assim, este estudo teve como objetivo avaliar os parâmetros envolvidos na tomada de decisão de cirurgiões dentistas clínicos e especialistas para a realização do tratamento endodôntico em sessão única ou múltiplas sessões. Para tanto, este estudo contou com uma coleta de dados através de um questionário online, aplicado cirurgiões dentistas clínicos gerais e especialistas em endodontia. As respostas foram tabuladas e analisadas por meio de estatística descritiva. Os resultados revelaram que a maioria dos endodontistas e dos clínicos gerais prefere realizar tratamento endodôntico em sessão única, devido ao menor desperdício de material, além do melhor domínio da anatomia e tratamento em um único momento. O motivo mais comum para os endodontistas e clínicos gerais escolherem o tratamento com múltiplas visitas é para dentes com prognóstico duvidoso e os casos em que o profissional aguarda a remissão dos sintomas antes da obturação. Em conclusão, a maioria dos endodontistas e dos clínicos gerais preferiu realizar tratamento endodôntico em sessão única.

In dentistry, treatment decisions are made exclusively by dental surgeons and their perceptions, including treatment philosophy, which means that the practice of new concepts, treatments or techniques depends not only on their logic or biological efficacy. Therefore, the aim of this study was to evaluate the parameters involved in clinical and specialist dental surgeons' decision to carry out endodontic treatment in single or multiple sessions. To this end, data was collected using an online questionnaire administered to general dental surgeons and endodontic specialists. The answers were tabulated and analyzed using descriptive statistics. The results revealed that the majority of endodontists and general practitioners prefer to carry out endodontic treatment in a single session, due to less wastage of material, as well as better mastery of the anatomy and treatment at a single time. The most common reason for endodontists and general practitioners to choose treatment with multiple visits is for teeth with a doubtful prognosis and cases in which the professional is waiting for symptoms to remit before filling. In conclusion, the majority of endodontists and general practitioners preferred to carry out endodontic treatment in a single session.

Patient-related predictors of post-operative pain following root canal treatment: A structural model analysis.

AIM: The pathways to post-operative pain are complex and encompass factors that extend beyond the treatment protocol employed. This study aimed to identify patient-related predictors of post-operative pain following root canal treatment. METHODOLOGY: A total of 154 patients received a single-visit root canal treatment for asymptomatic necrotic mandibular molars. Before treatment, dental anxiety, dental fear and sense of coherence (SOC) were measured as predictors for each patient using validated questionnaires. Other measured predictors included gender, age, previous negative experiences at the dental offices and prior root canal treatment. Post-operative pain was assessed using the Numeric Rating Scale at multiple time-points over 30 days. Structural equation analysis was employed to evaluate the direct and indirect effects of patient-related predictors on a theoretical model of post-operative pain. The irrigant solution was also included in the model, as it was the only aspect that varied in the treatment protocol (sodium hypochlorite 2.5% and 8.25%). RESULTS: Dental anxiety (coefficient 0.028; p < .01), dental fear (coefficient 0.007; p = .02) and irrigant solution (coefficient 0.004; p = .03) exerted a direct effect on post-operative pain. SOC exerted an indirect effect on post-operative (coefficient 0.006; p = .01) through dental anxiety and dental fear. Moreover, previous negative experiences (coefficient 0.048; p = .04) exerted an indirect effect on post-operative pain through dental anxiety. CONCLUSIONS: Dental anxiety, dental fear, previous negative experiences and SOC are patient-related predictors of post-operative pain following root canal treatment. These factors should be taken into consideration in clinical practice, as patients with these characteristics may be at an increased risk of experiencing post-operative pain.

Minimally invasive guided endodontic microsurgery with Zekrya bur: A 48-month follow-up case report.

Endodontic microsurgery guided by navigation systems represents a precise and minimally invasive approach for retreatment of apical periodontitis following failed conventional endodontic therapy. Accurate localization and minimal access to the root apex are paramount for successful outcomes and preservation of anatomical structures. Workflow considerations, such as three-dimensional (3D) virtual planning and endodontic guidance represent new crucial aspects for addressing complex cases. This clinical case report presents the successful reintervention of a complex case using a Zekrya bur, operative microscopy, cone beam computed tomography and biocompatible materials. After a 48-month follow-up, complete healing of the treated area was observed. This minimally invasive technique, employing a simple instrument widely available globally, underscores the potential for efficient and predictable outcomes in complex endodontic microsurgical retreatment.

Dissimilar Sequelae Caused by Single Dental Trauma: A Case Report with Long-Term Follow-up.

Immediate care and accurate diagnosis are essential for treating dental trauma. This report presents a 7-year-old boy suffered a bicycle accident with direct trauma to the mouth and extrusive luxation of teeth #11 and #21. The emergency treatment was performed within the first hour. Clinical examinations showed that both teeth exhibited 3 mm extrusion from comparing their incisal edges to their neighboring teeth, had edematous gingiva, showed grade 3 mobility and were painful to percussion. Radiographic exams showed incomplete root formation, widened periodontal spaces along their entire lengths and absence of bone or root fractures. The treatment consisted of immediate repositioning and semi-rigid splinting. After 15 days, tooth #11 exhibited no clinical signor symptom and tooth #21 was diagnosed with pulp necrosis, with an acute dentoalveolar abscess and intraoral edema. Immediate endodontic treatment was initiated (intracanal dressing with calcium hydroxide paste). At 30 days, another pulp sensibility test was performed on tooth #11, which had a negative response. In the same visit, the intracanal dressing of tooth #21 was replaced. The Ca(OH)2 medication was replaced every 6 months until the formation of an apical barrier. The final dressing consisted of gutta-percha and Grossman's sealer and was placed two and a half years after the first dressing appointment. The extrusive luxation resulted in two different sequelae: complete root obliteration in tooth #11 and anomalous root development after the formation of an apical barrier in tooth #21. The patient received orthodontic treatment after 6 years from the initial treatment with no negative outcome. After 18 years follow-up, both teeth were stabilized with no symptom or sign. It's important to follow the evolution of every trauma case continuously because the sequelae can be unpredictable.

Comparing the Efficiency of Single versus Dual Ultrasonic Devices for Metallic Post Removal in Endodontic Retreatment: A Clinical Study.

Introduction: Ultrasonic vibration for metallic post removal seems to be a unanimous choice between endodontists and general practitioners for providing the best results and having the highest safety. This study compared the time required by ultrasonic vibration for removing metallic post (MP) when 1 or 2 ultrasonics devices are used. Materials and Methods: One hundred and fifteen teeth with MPs from 105 patients, indicated for nonsurgical endodontic retreatment were divided into 2 groups according to the number of ultrasonic devices used (G1-1 device) and (G2-2 devices). In G1, the MP was worn with a transmetal bur, alongside the wear of the cement line (around 2 mm deep). Then, an ultrasonic tip attached to an ultrasonic unit, with a power of 100% was activated at the level of the post, with constant water spray at a level of 1 mm above the axial surface of the tooth. The position of the tip was changed between buccal and lingual surfaces every 10 seconds until the MP was removed. In G2 the same procedures were performed as described in G1, but two ultrasonic tips were activated simultaneously at buccal and lingual surfaces until the MP was removed. The vibration time necessary for removing each MP was recorded using a chronometer. Results: The mean time was 131.10±29.68 seconds (mean±standard error of the mean) for MP removal using one ultrasonic device, and 24.86±6.88 seconds for two devices. The time required for MP removal using two ultrasonic devices was significantly less than when using one ultrasonic device (P<0.001). Conclusion: The technique with 2 ultrasonic devices proved to be more efficient than the one using only 1 ultrasonic device.

Guided Endodontic Treatment of Mandibular Incisor with Pulp Canal Obliteration following Dental Trauma: A Case Report.

Root canal obliteration is caused by hard tissue apposition and is often associated with teeth with a history of trauma, orthodontic movement, caries reaction, restorative procedures near the pulp chamber, and teeth of elderly patients. Preoperative planning of root canal treatment should be thorough and include an assessment of the patient's signs and symptoms in addition to the evaluation of complementary examinations. In a 27-year-old patient with dyschromia of the lower central incisor, a history of dental trauma, and a positive response to vertical percussion, an initial periapical radiograph was obtained that showed calcification of the canal and presence of a periapical lesion. The patient presented with pain on chewing, a positive response to palpation and a vertical percussion test. The diagnosis was symptomatic apical periodontitis. A cone-beam computed tomography scan was requested and a surface scan was performed to establish a static guide. The root canal was accessed in the middle third of the root and the canal was located using a minimally invasive approach. The root canal was treated conventionally. Results obtained showed the success of the treatment after a 3-year clinical and radiographic follow-up. Therefore, the use of an endodontic guide in cases of calcified canals significantly reduces the clinician's working time and offers a more predictable approach to the treatment of these pathologies.

Reducing Apical Bacterial Extrusion: The Impact of Reciproc File Size and Irrigation Technique.

Introduction: This study used different irrigation techniques to compare the levels of apical bacterial extrusion during the preparation of root canals with a reciprocating instrument widely used in endodontics, the Reciproc files 25/0.08 and 40/0.06. Materials and Methods: The irrigation techniques employed were conventional syringe irrigation and passive ultrasonic irrigation (PUI); the latter, with one or two activation cycles. Seventy extracted mandibular human premolars were contaminated with Enterococcus faecalis for 5 days and were distributed into 6 experimental groups (n=10), and the remaining specimens were used as positive and negative control groups (n=5). Group 1: instrumentation performed with Reciproc 25/0.08 and conventional syringe irrigation; Group 2: instrumentation performed with Reciproc 25/0.08 along with PUI for one minute after instrumentation (PUI-1); and Group 3: instrumentation performed with Reciproc 25/0.08 along with PUI for one minute before and after instrumentation (PUI-2). Groups 4, 5 and 6 were instrumented with Reciproc 40/0.06, and irrigation was performed similar to the previous groups, in the aforementioned order. Each root canal was irrigated with saline solution. Extruded debris was collected in microtubes. The contents of the microtubes were homogenized, diluted, and spread on Brain Heart Infusion agar. After 48 hours, the number of colony-forming units was determined for each sample. For statistical analysis, the Kruskal-Wallis test followed by the Dunn's tests were used (α=0.05). Results: The CFU/mL count indicated that the instrumentation with Reciproc 25/0.08 was associated with the highest bacterial extrusion, mainly when PUI was performed (P<0.05). Conclusion: All the instrumentation techniques caused bacterial extrusion through the apical foramen; however, the largest file size of the Reciproc 40/0.06 groups was associated with less apical bacterial extrusion.

[Effectiveness of curcumin as photodynamic therapy for endodontic procedures: a narrative review]. / Efectividad de la curcumina como terapia fotodinámica para los procedimientos de endodoncia: una revisión narrativa.

Introduction: Endodontic therapy is performed by biomechanical preparation and intracanal medication; however, residual bacteria can be compromised due to their ability to adhere to the root canal walls. Therefore, photodynamic therapy has gained popularity because of its good ability to prevent and eradicate microbial infections by using a light-activated dye. Objective: Analyze and to update the information on the effect of curcumin in photodynamic therapy in root canal treatment. Material and Methods: A literature search was carried out in PubMed/MEDLINE, Scopus, Ebsco, Science Direct, and LILACS databases using the keywords "curcumin", "turmeric", "photodynamic", "photochemotherapy", "photoradiation", "photoactivated disinfection", "root canal disinfection", "root canal therapy", "endodontics" in both Spanish and English, from 2018 to 2023. Results: Information from the last five years was collected with the aim of updating the study topic. 749 articles were examined using inclusion and exclusion criteria, of which only 50 met these criteria and were analyzed. Current studies show the effects of therapy on the contamination of the root canal biofilm with E. faecalis, demonstrating that photoactivated curcumin promotes the disruption of the biofilm and reduction of Colony-Forming Units. Conclusions: Curcumin as a photosensitizer demonstrates a potential antibacterial effect significantly decreasing the viability of microbial cells and the vitality of biofilms.

[Acute apical abscess and associated factors in patients during the covid-19 pandemic in a health center in Acapulco, Mexico.] / Absceso apical agudo y factores asociados en pacientes durante la pandemia de covid-19 en un centro de salud de acapulco, méxico.

Objective: To estimate the prevalence of acute apical abscess and identify associated factors in patients of a health center from Acapulco, Mexico. Material and methods: Epidemiological study that collected clinical records of patients during the period of october 2021. Sociodemographic and housing information was collected, as well as personal pathological and non-pathological history and a record of the diagnosis of the periapical lesion based on its clinical characteristics issued by the operator on duty. Through multivariate analysis, a factor associated with acute apical abscess was identified with the odds ratio and its 95% confidence interval as estimators of the strength of association with CIETmap statistical software. Results: The 37% (32/87) of patients were diagnosed with the infection. In terms of gender, females were the most affected with a proportion of 56% (18/32). The most common cause was caries with 72% (23/32). The right upper second premolar was the most affected tooth with 25% (8/32). One associated factor was identified, age 36 to 62 years (ORa=3.54; CI95%a=1.27 -16.62). Conclusion: The morbidity rate of the infection was moderate, and it is a common pathology in stomatological emergency consultations, so it is important for the professional in charge of the area to manage it clinically. It will be important to implement oral health education strategies aimed at different age groups to raise awareness of the cariogenic process and its consequences.

Impact of CBCT acquisition protocols and artifact reduction filters on diagnosing vertical root fractures.

AIM: To evaluate the impact of acquisition protocols and artifact reduction filters in cone beam computed tomography on diagnosing vertical root fractures in endodontically treated teeth with and without intraradicular posts. MATERIALS AND METHODS: We analyzed 480 tomographic images acquired from two J. Morita scanners (0.125- and 0.08-mm voxel sizes protocols), with application of a blooming artifact reduction filter. Three evaluators assessed these images for root fractures using a 5-point Likert scale. Diagnostic accuracy between filters and protocols was determined using generalized linear models with binomial distribution for the outcome, considering protocol, filter, and dental status. Sensitivity, specificity, positive predictive value, and negative predictive value were also estimated for the filters and protocols. RESULTS: The 0.08-mm voxel size protocol demonstrated a significantly higher percentage of accurate diagnosis compared to the 0.125-mm protocol (p = .001). No statistically significant differences (p ≥ .087) were observed for filter application, interaction between protocol and filter, or dental status. Accuracy, sensitivity, and specificity values were respectively: .93, .87, 1.00 (protocol 1); .99, .99, .99 (protocol 2); .98, .96, .99 (no filter); .95, .90, 1.00 (with filter). CONCLUSION: The new findings found for the two J Morita scanners used in our study were that images acquired using the voxel size of 0.08 mm showed an improvement in the diagnosis of root fractures and the filters in these devices have no relevance significant for the diagnosis.

Exploring access cavity through non-carious cervical lesions: Impacts on instrumentation, obturation, and fracture resistance in mandibular incisors.

AIM: To compare the effects of Cervical Access Cavity (CervAC) and Traditional Access Cavity (TradAC) on root canal preparation, root canal filling, and fracture resistance in mandibular incisors. METHODOLOGY: Twenty recently extracted and intact mandibular incisors were initially scanned using a micro-CT device. The specimens were anatomically matched to create two groups (n = 10). A wedge-shaped non-carious cervical lesion (NCCL) was created on the buccal aspect of all teeth using a double-faced segmented diamond disc. In group 1, a TradAC was prepared, whilst in group 2, access was created through the simulated NCCL using a round diamond bur 1012. After root canal preparation with Rotate instruments sizes 15/0.04, 20/0.04, and 25/0.04, the teeth were scanned again and evaluated for root canal volume and surface area, static voxels, volume of removed dental tissue, and dentine thickness. After that, the root canals were filled using the single-cone technique, teeth were restored with composite resin, and subsequently rescanned to calculate the volume of filling materials and voids. Then, the restored teeth were subjected to fracture resistance tests using a universal testing machine. Statistical comparisons between groups were performed with the Mann-Whitney test or the Student's t-test, with a statistical significance level of 5%. RESULTS: Statistical comparisons indicated no significant differences between groups in terms of root canal volume, surface area, static voxels, removed root dentine, root canal filling volume, percentage of voids, or fracture resistance load (p > .05). Conversely, teeth prepared with TradAC showed a significantly higher percentage of dental tissue removed from the crown (p = .001) and a greater volume of filling material remnants in the pulp chamber (p < .001) compared to the CervAC group. A significantly lower percentage reduction in dentine thickness was observed only on the mesial aspect of root at Level 1 in TradAC group (p = .008). CONCLUSIONS: CervAC can be considered a viable alternative approach in the presence of NCCL in mandibular incisors.

Apical periodontitis as an aggravating factor for the severity of rheumatoid arthritis: An animal study.

AIM: The present study investigated the influence of apical periodontitis (AP) on the severity of rheumatoid arthritis (RA) using a Wistar rat model. METHODOLOGY: Forty male Wistar rats were distributed across four groups (n = 10) based on the induction of RA and AP: Control, RA, AP, and RA + AP. RA was induced through two immunisations with type II collagen emulsified in incomplete Freund's adjuvant, followed by one immunisation with complete Freund's adjuvant. After 21 days of RA induction, AP was induced by exposing the pulp of four molars. Animals were euthanized after 28 days of pulp exposure. Through the experiment, visual and behavioural assessments tracked RA development and the knees and hind paw joints were measured. Micro-computed tomography scans of knees and hind paws, as well as mandibles and maxillae, were conducted to evaluate RA severity and the presence of AP, respectively. Serum samples were collected to analyse proinflammatory cytokines (IL-1ß, IL-2, IL-17, and TNF-α). Non-parametric data were analysed using the Kruskal-Wallis test followed by Student-Newman-Keuls test, while one-way anova followed by Tukey's test was performed for parametric data. A significance level of 5% was employed. RESULTS: All molars submitted to access cavity developed AP. All joints subjected to arthritis induction developed the disease, with AP + RA demonstrating a higher arthritis severity when compared to the RA group (p < .05). RA + AP group displayed a significantly larger hind paw and knee circumference compared to the RA group (p < .05). Micro-CT images of RA and RA + AP groups revealed joints with erosions and bone deformities, with a significantly lower bone surface density, lower trabecular number and higher trabecular separation in the hind paw and a significantly lower percent bone volume and higher trabecular separation in the knees of RA + AP group compared to RA group (p < .05). RA + AP group exhibited a significantly higher level of TNF-α and a lower level of IL-2 compared to all other groups (p < .05). Both RA and RA + AP groups had significantly higher IL-17 levels (p < .05), while there was no significant difference in IL-1ß levels among the groups (p > .05). CONCLUSION: The findings from this study underscore a possible relationship between apical periodontitis and the exacerbation of rheumatoid arthritis.

Root Canal Dentin Microhardness after Contact with Antibiotic Medications: An In Vitro Study.

Background: Antibiotic pastes used as intracanal medication in cases of revascularization therapy might cause negative effects on tooth properties, such as a reduction in dentin microhardness. This in vitro study investigated dentin microhardness in three different locations distancing from the canal lumen after 20 days of treatment with a tri-antibiotic paste (ciprofloxacin, metronidazole, and minocycline), and with a double-antibiotic paste (ciprofloxacin and metronidazole), with calcium hydroxide [Ca(OH)2] UltracalTM XS-treated dentin as comparison. Material and Methods: Human mandibular premolars (n = 48) had the root canals cleaned and shaped and were used to produce dentin slices. Dentin slices remained immersed in the medications for 20 days. The Knoop microhardness (KHN) test was performed before (baseline/Day-0) and after treatment (Day-20) with the medications. Indentations were made at 25 µm, 50 µm, and 100 µm distances from the root canal lumen. The KHN was compared intra-group using Wilcoxon's test. Independent groups were compared using Mann-Whitney's and Kruskal-Wallis' tests, at α = 5%. Results: The microhardness in all the tested groups was reduced at Day-20 in comparison with Day-0 (p < 0.001) (intra-group comparison/same distances). The Day-0 values were similar, and the Day-20 values were higher for the Ca(OH)2 group (p < 0.05) (comparison between groups/same distances). Conclusions: Calcium hydroxide for 20 days would be preferred rather than antibiotic pastes to minimize the expected reduction in dentin microhardness during regenerative procedures.

Cytocompatibility and Antibiofilm Activity of Calcium Hydroxide Mixed with Cyperus articulatus Essential Oil and Bio-C Temp Bioceramic Intracanal Medicament.

Calcium hydroxide represents the most commonly used intracanal dressing between sessions; however, it may not be effective against all types of microorganisms. Several compounds of plant origin have attracted increasing attention from researchers in recent years. The objective of this study was to evaluate the cytocompatibility and antimicrobial activity of calcium hydroxide associated with the essential oil of Cyperus articulatus and the new bioceramic intracanal medicament Bio-C Temp®. Five experimental groups were designed: group Ca-C. articulatus essential oil; group CHPG-calcium hydroxide associated with propylene glycol; group CHCa-essential oil of C. articulatus associated with calcium hydroxide; and group U-UltraCal® XS; group BCT-Bio-C Temp®. The control group was a culture medium. Cytocompatibility was assessed by the methyltetrazolium (MTT) assay after exposure of the Saos-2 human osteoblast-like cell line to dilutions of commercial products/associations for 24 h and 72 h. The antimicrobial activity against mature Enterococcus faecalis biofilm was evaluated by the crystal violet assay. All commercial products/associations showed a cell viability similar to or even higher than the control group (p > 0.05) for both periods evaluated. C. articulatus essential oil associated or not with calcium hydroxide showed better antibiofilm capacity. C. articulatus associated or not with calcium hydroxide showed superior cytocompatibility and antimicrobial capacity, representing a promissory intracanal medicament.

Systemic administration of propranolol reduces bone resorption and inflammation in apical periodontitis of chronically stressed rats.

AIM: To evaluate the effect of systemic administration of propranolol on the severity of apical periodontitis (AP) in chronically stressed rats. METHODOLOGY: Twenty-four 70-day-old male Wistar rats (Rattus norvegicus, albinus) were distributed into three groups (n = 8): rats with AP without stressful conditions (AP-Control), rats with AP and submitted to a chronic unpredictable stress (CUS) protocol (AP + S) and rats with AP and submitted to a CUS protocol treated with propranolol (AP + S + PRO). Stress procedures were applied daily until the end of the experiment. After 3 weeks of CUS, AP was induced in all groups by exposing the pulpal tissue of mandibular and maxillary first molars to the oral environment. Propranolol treatment was administered orally once a day for the entire period of the experiment. Rats were sacrificed at 42 days, and the blood was collected for stress biomarkers serum dosage by multiplex assay. Mandibles were removed and submitted to microtomography and histopathological analyses. Periapical tissue surrounding the upper first molar was homogenized and subjected to RT-PCR analysis to evaluate the mRNA expression of RANKL, TRAP and OPG. Parametric data were assessed using one-way ANOVA followed by Tukey's test while the nonparametric data were analysed by the Kruskal-Wallis followed by Dunn's test. Significance level was set at 5% (p < .05) for all assessed parameters. RESULTS: Micro-CT revealed statistically significant differences in bone resorption which was greater in the AP + S group (p < .05), but no differences were observed between the Control and AP + S + PRO groups (p > .05). The AP + S + PRO group had a lower intensity and extent of inflammatory infiltrate compared to the AP + S group with smaller areas of bone loss (p < 0.05). The gene expression of RANKL and TRAP was significantly higher in the stressed group AP + S compared to the control group (p < .05), and a significantly higher OPG expression was observed in AP + S + PRO compared to the AP + S group (p < .05). CONCLUSIONS: Oral administration of propranolol had a significant effect on the AP severity in stressed rats, suggesting an anti-inflammatory effect and a protective role on bone resorption of AP in stressed animals. Further research is necessary to fully comprehend the underlying mechanisms.

Top 100 most-cited scientific articles in regenerative endodontics 2019-2023: A bibliometric analysis.

BACKGROUND: Bibliometric analysis is a critical indicator of the influence and relevance of scientific papers, whilst also highlighting key contributors and gaps in knowledge in a scientific field. OBJECTIVES: To update and analyse the 100 most-cited papers in regenerative endodontics from 2019 to 2023. METHODS: A search of the most-cited recent papers focusing on regenerative endodontics using journals included in the category, 'Dentistry, Oral Surgery & Medicine', in the Clarivate Web of Science database from 2019 to 2023 was performed. Three researchers conducted the study selection and data extraction. Data extraction included publication title and year, authors, number and mean number of citations, institution, country and continent, study design, journal title, keywords and research topic. Citation counts were also collected in Google Scholar and Scopus databases. Graphical bibliometric networks were created using VOSviewer software. RESULTS: The number of citations of the 100 most-cited articles ranged from 6 to 85. Most were published in 2020 (n = 48), principally in the Journal of Endodontics (47%), followed by International Endodontic Journal (13%), Journal of Dental Research (6%) and Dental Materials (6%). Laboratory study was the most common study design amongst the included papers (n = 47), followed by narrative reviews (n = 17) and observational studies (n = 16). The most frequent first author on the top three most-cited papers was Hacer Aksel, whilst Adham A. Azim (n = 6; 89 citations) contributed most to the top 100 articles. The institution from which most articles originated was the University of Hong Kong (China) (n = 5; 81 citations), whereas the corresponding authors were predominantly from the United States of America (USA) (n = 31; 560 citations). The VOSviewer map of co-authorship demonstrated research collaborative clusters. 'Regenerative endodontics' and 'stem-cells' were the most employed keywords (37 and 36 occurrences respectively). DISCUSSION: The current study was designed not only to showcase the most influential papers in regenerative endodontics since 2019 but also to provide a better understanding of global research in this area over the last five years. CONCLUSIONS: This bibliometric analysis highlighted papers, authors, institutions and keywords in regenerative endodontics. The 100 most-cited papers primarily consisted of laboratory studies published in the USA, focusing on evaluating biomaterials and scaffold design strategies in contact with stem cells. Clinical studies and systematic reviews representing higher levels of scientific evidence are currently not the most influential in the regenerative endodontic field.

Evaluation of pulp tissue dissolution capacity through different sodium hypochlorite agitation protocols.

Aims: This ex vivo study aimed to assess the dissolving capacity of 2.5% sodium hypochlorite using eight agitation protocols within swine pulp tissue. Subjects and Methods: Twelve lower first premolars were prepared and split into the fragments with a groove housing porcine dental pulp. Groups were assigned based on agitation systems: manual, passive ultrasonic, Easy Clean and XP-Endo Finisher. Two agitation time protocols were applied: One min (3 s × 20 s cycles) and 2 min (6 s × 20 s cycles). Wilcoxon Mann-Whitney U test was used to compare the groups. Results: Both time frames demonstrated superior results compared to manual group (P > 0.5). However, in the two min groups, no significant differences were observed among the other protocols (P < 0.5). Intriguingly, increasing cycle numbers significantly improved results within each group (P > 0.5). Conclusion: Extending the chemical agitation time during final irrigation enhances tissue removal, regardless of the irrigation protocol employed.

Quality analysis of four filling techniques in ovoid root canals prepared with M® instruments

Aims: This study aimed to assess the quality of various filling techniques in ovoid root canals prepared using M® instruments. Materials and Methods: Sixty ovoid root canals underwent endodontic treatment with M® instruments and were subsequently divided randomly into four experimental groups, each employing a different obturation technique: TU - single cone; TL - active lateral condensation; TH - Tagger hybrid; TS - Schilder technique. Digital radiographs were taken in both mesiodistal and buccolingual directions to examine the filled teeth. The percentage of filling material and empty spaces was quantified using Photoshop® software. Data were subjected to statistical analysis using the one-way ANOVA test and T test (? = 0.05). Results: In the TL and TS groups, there was a significantly lower average percentage of unfilled spaces compared to the TU and TH groups (P<0.0001). When analyzing the radiographic directions, the mesiodistal view exhibited the highest mean percentage of unfilled spaces, with differences in filling quality observed only in the TU and TL groups. Conclusions: Active lateral condensation and Schilder techniques demonstrated superior performance in achieving effective filling of ovoid root canals.