In Vitro and In Vivo Efficacy of New Composite for Direct Pulp Capping.

OBJECTIVES: To investigate physicochemical properties, dentin bonding, cytotoxicity, and in vivo pulp response of experimental self-adhesive composites tailored to direct pulp capping. MATERIALS AND METHODS: Experimental composites were prepared with beta-tricalcium phosphate and hydroxyapatite nanoparticles adsorbed with simvastatin and glutathione added at 0% (control resin), 1 wt% (Res 1%), and 10 wt% (Res 10%). A commercial light-curable calcium hydroxide (Ca(OH)2) (Ultra-Blend Plus) was used as control material. The physicochemical properties investigated were flexural strength and modulus, calcium release, and degree of conversion. Dentin bonding was assessed by the push-out test. Proliferation and cell counting assays were performed to evaluate in vitro cytotoxicity using fluorescence microscopy. In vivo pulp capping was performed on molars of Wistar rats, which were euthanized after 14 days and evaluated by histological analysis. RESULTS: No statistical difference was observed in flexural strength and cell viability (p > 0.05). Res 10% presented higher modulus than control resin and Ca(OH)2. Also, Res 10% attained statistically higher degree of conversion when compared to other experimental composites. Ca(OH)2 showed higher calcium release after 28 and 45 days of storage, with no statistical difference at 45 days to Res 10%. All experimental composites achieved significantly higher bond strength when compared to Ca(OH)2. While no significant difference was observed in the cell proliferation rates, resins at lower concentrations showed higher cell viability. In vivo evaluation of pulp response demonstrated no pulp damage with experimental composites. CONCLUSIONS: The experimental composite investigated in this study achieved adequate physicochemical properties with minor in vivo pulpal inflammation and proved to be a valuable alternative for direct pulp capping.

Antimicrobial Effect of Calcium Hydroxide Combined with Electrolyzed Superoxidized Solution at Neutral pH on Enterococcus faecalis Growth.

OBJECTIVE: To evaluate the effect of the combination of calcium hydroxide (Ca(OH)2) and a novel electrolyzed superoxidized solution at neutral pH, known as OxOral® on Enterococcus faecalis growth in root canals. METHODS: Sixty human teeth were used, from which root canals were infected and randomly divided into the following treatment groups: saline solution, saline solution plus Ca(OH)2, OxOral®, and OxOral® plus Ca(OH)2. RESULTS: A permanent reduction in bacterial growth was observed at days 1, 6, 12, and 18 after OxOral® plus Ca(OH)2 treatment from 4.4 ± 0.074 log10 CFU/mL to 0.0 ± 0.001 log10 CFU/mL. In addition, alkaline conditions maintenance was observed from application time (pH = 12.2 ± 0.033) to 18 d posttreatment (pH = 12.6 ± 0.083). CONCLUSION: The combination of OxOral® and Ca(OH)2 provides an alkaline pH and inhibits E. faecalis growth into the root canals. Our study opens the possibility for further research on the use of OxOral® in endodontic therapy.

Establishment and utilization of an evaluation system for virucidal activity of disinfectants against a coronavirus with apparent applicability to SARS-CoV-2.

Decontamination of pathogens on surfaces of substances is very important for controlling infectious diseases. In the present experiments, we tested various disinfectants in aqueous phase as well as on plastic surface carrying a viral inoculum, through dropping and wiping decontamination techniques, comparatively, so as to evaluate virucidal efficacies of those disinfectants toward an avian coronavirus (infectious bronchitis virus: IBV). We regard this evaluation system applicable to SARS-CoV-2. The disinfectants evaluated were 0.17% food additive glade calcium hydroxide (FdCa(OH)2) solution, sodium hypochlorite at 500 or 1,000 ppm of total chlorine (NaClO-500 or NaClO-1,000, respectively), NaClO at 500 ppm of total chlorine in 0.17% FdCa(OH)2 (Mix-500) and quaternary ammonium compound (QAC) diluted 500-fold in water (QAC-500). In the suspension test, all solutions inactivated IBV inoculum that contained 5% fetal bovine serum (FBS) under detectable level within 30 sec. In the carrier test, all solutions, except NaClO-500, could inactivate IBV with 0.5% FBS on a carrier to undetectable level in the wiping-sheets and wiped-carriers. We thus conclude that suspension and carrier tests should be introduced to evaluate disinfectants for the field usage, and that this evaluation system is important and workable for resultful selection of the tested disinfectants against avian coronavirus and SARS-CoV-2 on surfaces, particularly on plastic fomite.

Destoxificação e perfil nutricional da torta de mamona destoxificada por diferentes soluções alcalinas / [Detoxification and nutritional profile of the detoxified castor by different alkaline solutions]

Objetivou-se avaliar a destoxificação da torta de mamona bruta (TMB), por meio de dois produtos alcalinos em diferentes concentrações, e seus efeitos sobre a composição química, a degradabilidade in situ da MS e o fracionamento de proteínas. Utilizou-se o hidróxido de cálcio [Ca(OH)2] e o hidróxido de sódio (NaOH) em duas concentrações (60 e 90 gramas), diluídos em quatro quantidades de água (1.000; 1.500; 2.000 e 2.500mL de água por quilo de TMB). Observou-se que, das diferentes concentrações utilizadas, somente a utilização de 90 e 60 gramas de Ca(OH)2 e NaOH, respectivamente, conseguiu destoxificar 100% da TMB, ambas diluídas em 2.000mL de água. Por outro lado, ao avaliar o tempo mínimo de contato dos reagentes com a TMB para uma máxima destoxificação, observou-se que três horas de contato é o tempo necessário para os reagentes diminuírem em 100% as proteínas citotóxicas, além de não deixar atividade hemaglutinante nesse material. A destoxificação com o NaOH proporcionou maior degradação das proteínas solúveis e da matéria seca, favorecendo a disponibilização do nitrogênio não proteico, estando sua aplicação em escala industrial na dependência de estudos sobre viabilidade operacional e econômica.(AU)

This study aimed to evaluate the detoxification of crude castor (DCC) through two alkaline products in different concentrations and their effects on the chemical composition, in situ degradability of DM and the fractionation of proteins. We used the calcium hydroxide [Ca(OH)2] and sodium hydroxide (NaOH) in two concentrations (60 and 90 grams) diluted in 4 quantities of water (1,000; 1,500; 2,000 and 2,500ml of water per kilo of DCC). It was observed that in the different concentrations used, only the use of 90 and 60 grams of Ca(OH)2 and NaOH, respectively managed to detoxify 100% of the DCC, both diluted in 2,000ml of water. On the other hand, when assessing the minimum time of contact of the reagents with the DCC for maximum detoxification, it was observed that with three hours of contact is the time required for the reagents decrease in 100% of the cytotoxic proteins, in addition to not leave haemagglutinating activity in this material. The detoxification with NaOH provided greater degradation of soluble proteins and degradation of dry matter, favoring the provision of non-protein nitrogen, while its application on an industrial scale is in the dependence of studies on operational feasibility and cost.(AU)

Efficacy of calcium hydroxide and chlorhexidine in pulp revascularization after trauma in young permanent teeth.

The objective of this study is to observe and analyze the efficacy of calcium hydroxide and chlorhexidine in pulp revascularization after trauma in young permanent teeth. A total of 120 patients who were treated in our hospital for pulp revascularization after trauma in young permanent teeth were enrolled as research objects in the study. The patients were treated with calcium hydroxide and chlorhexidine and the overall treatment efficiency was statistically observed. The improvement in various indicators before and after treatment was observed, including pain symptom score, gum swelling symptom score, tooth looseness score. The overall treatment efficiency was recorded. The results showed that there were 70 cases of significant effective treatment, 42 cases of effective treatment, and 8 cases of ineffective treatment, respectively, with overall treatment efficiency of 93.33%. Compared with the pain score, gum swelling score and teeth looseness score before treatment, these indicators showed a significant improvement after treatment, p<0.05. The application of calcium hydroxide and chlorhexidine during pulp revascularization after trauma in young permanent teeth can significantly improve the therapeutic effect and achieve higher therapeutic efficiency, demonstrating huge application value.

Comparative evaluation of the efficacy of three methods of delivering calcium hydroxide into the root canal.

BACKGROUND: Calcium hydroxide, due to its favorable properties, such as an antimicrobial effect as well as its ability to dissolve necrotic tissues, inhibit tooth resorption and stimulate the formation of a hard tissue barrier, is widely used in root canal treatment. OBJECTIVES: The objective of this study was to compare the efficacy of 3 methods of delivery of calcium hydroxide into the canals. MATERIAL AND METHODS: This in vitro experimental study was performed on acrylic resin blocks with simulated curved canals (curvature of 24° and 44°). Calcium hydroxide was delivered into the canals with 3 different instruments : a hand file, a Lentulo and a rotary file. The data was analyzed using the three-way analysis of variance (ANOVA) and Tukey's test. RESULTS: The density of calcium hydroxide was significantly different among the 3 groups (p < 0.001). The manual delivery technique resulted in the lowest and using a rotary file in the highest density of calcium hydroxide (p < 0.001). The mean density of calcium hydroxide was significantly higher in the canals with curvature of 24°, irrespective of the delivery method (p < 0.001). The lowest mean density of calcium hydroxide was noted at 1 mm and 3 mm from the apex, whereas the highest mean density was noted at 11 mm from the apex, irrespective of delivery method (p < 0.001). CONCLUSIONS: A rotary file seems to be the most efficient instrument for delivering calcium hydroxide into the canals, especially into the apical region of canals with greater curvature.

In vitro treatment of Enterococcus faecalis with calcium hydroxide impairs phagocytosis by human macrophages.

OBJECTIVE: Monocyte-derived macrophages (MDMs) ability to phagocytize and produce nitric oxide (NO) was tested against root-canal strains of Enterococcus faecalis submitted to alkaline stress. Root-canal strains were also compared with urine Enterococci. MATERIALS AND METHODS: Enterococcus faecalis were stressed with alkaline-BHI broth and incubated in vitro at a cell/bacteria ratio of 1:5. Phagocytosis was analyzed by fluorescence microscopy using acridine orange stain, and NO concentration was measured in supernatants. RESULTS AND CONCLUSIONS: Alkaline-stress significantly impaired MDMs phagocytosis of E. faecalis strains analyzed, except in ATCC4083 isolated from a pulpless tooth, but NO production was unchanged. Comparison of different strains showed the urine isolate had higher NO levels than root canal strains. Alterations in the bacterial cell wall structures after alkaline-stress possibly made bacteria less recognizable and phagocytized by MDMs but did not affect their ability to activate NO production. Furthermore, root canal strains elicited different responses by immune cells compared with strains from urine. Clinically, impaired phagocytosis of E. faecalis could contribute to their persistence in root canal systems previously treated with calcium hydroxide.

Estimation of genomic instability and mitochondrial DNA damage induction by acute oral administration of calcium hydroxide normal- and nano- particles in mice.

Nowadays, there is increasing interest in using calcium hydroxide (Ca(OH)2) nanoparticles rather than normal-sized Ca(OH)2 because of its higher antimicrobial activities. However, the genotoxicity of Ca(OH)2 nanoparticles has not been well investigated. Therefore, this study was performed to estimate the possible genomic instability and mitochondrial DNA damage induction by normal and nano-sized Ca(OH)2 particles in mice. Oral administration of normal or nano-sized Ca(OH)2 particles induced DNA breakages and apoptosis causing genomic instability as a result of increased Calcium content, ROS and MDA levels and decreased SOD and Gpx activities reversely proportional to Ca(OH)2 particles size in the liver, brain and bone marrow tissues. However, decreases in mitochondrial membrane potential concurrently with downregulated expression of POLG, POLG1 and TFAM genes were only observed in the brain and bone marrow tissues confirmed mitochondrial DNA damage. In contrast, the expressions of POLG, POLG1 and TFAM genes have been improved and mitochondrial membrane potential has not unchanged in liver tissues. Conclusion: single oral administration of normal or nano-sized Ca(OH)2 particles induced genomic instability through ROS generation that exhausted the antioxidant defense system in the liver, brain and bone marrow tissues but impaired the mitochondrial DNA only in the brain and bone marrow tissues.

Antibacterial Activity of Rosmarinus officinalis, Zingiber officinale, Citrus aurantium bergamia, and Copaifera officinalis Alone and in Combination with Calcium Hydroxide against Enterococcus faecalis.

This study aimed to evaluate the efficacy of different concentrations of essential oils combined with calcium hydroxide against Enterococcus faecalis. Thirteen experimental groups were formed: NC (negative control); PC (positive control); GC (growth control); SC (sterilization control); RO (Rosmarinus officinalis); ROH (calcium hydroxide + RO); ZO (Zingiber officinale); ZOH (calcium hydroxide + ZO); AB (Citrus aurantium bergamia); ABH (calcium hydroxide + AB); CO (Copaifera officinalis); COH (calcium hydroxide + CO); DWH (calcium hydroxide and distilled water). After reconstitution of the E. faecalis strain, microdilution testing was performed to define the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The data were tabulated in an Excel spreadsheet, and the MIC and MBC were calculated in accordance with the Bacteriological Analytical Handbook. MICs in the range of 0 to 100 mg/ml were only observed in the ROH group. The RO, ROH, AB, ZO, and ZOH presented absolute data for MBC. Bacterial growth was detected in the DWH group at all concentrations tested. The combination of the essential oils tested here with calcium hydroxide appears promising as an intracanal medication in endodontic treatment because of its effectiveness against Enterococcus faecalis. Essential oils are important in endodontic therapy since calcium hydroxide, the gold standard intracanal medication, is not effective against E. faecalis.

Infection Control in Teeth with Apical Periodontitis Using a Triple Antibiotic Solution or Calcium Hydroxide with Chlorhexidine: A Randomized Clinical Trial.

INTRODUCTION: This randomized clinical study compared the antibacterial effectiveness of treatment protocols using either a triple antibiotic solution (1 mg/mL) or calcium hydroxide/chlorhexidine paste as interappointment medication in infected canals of teeth with primary apical periodontitis. METHODS: The root canals of single-rooted teeth with apical periodontitis were prepared by using a reciprocating single-instrument technique with 2.5% sodium hypochlorite irrigation and then medicated for 1 week with either a triple antibiotic solution (minocycline, metronidazole, and ciprofloxacin) at 1 mg/mL (n = 24) or a calcium hydroxide paste in 2% chlorhexidine gluconate (n = 23). Samples were taken from the canal at the baseline (S1), after chemomechanical preparation (S2), and after intracanal medication (S3). DNA extracts from clinical samples were evaluated for total bacterial reduction using a 16S ribosomal RNA gene-based quantitative polymerase chain reaction assay. RESULTS: All S1 samples were positive for the presence of bacteria, and counts were substantially reduced after treatment procedures (P < .01). Bacterial levels in S2 and S3 samples did not significantly differ between groups (P > .05). S2 to S3 reduction was 97% in the antibiotic group and 39% in the calcium hydroxide/chlorhexidine group; only the former reached statistical significance (P < .01). There were significantly more quantitative polymerase chain reaction-negative S3 samples in the antibiotic group than in the calcium hydroxide group (P < .05). CONCLUSIONS: Interappointment medication with a triple antibiotic solution at the concentration of 1 mg/mL significantly improved root canal disinfection, and its effects were at least comparable with the calcium hydroxide/chlorhexidine paste. Effectiveness and easy delivery of the antibiotic solution make it an appropriate medicament as part of a disinfecting protocol for conventional nonsurgical endodontic treatment and possibly regenerative endodontic procedures.

Development of a portable mini-generator to safely produce nitric oxide for the treatment of infants with pulmonary hypertension.

OBJECTIVES: To test the safety of a novel miniaturized device that produces nitric oxide (NO) from air by pulsed electrical discharge, and to demonstrate that the generated NO can be used to vasodilate the pulmonary vasculature in rabbits with chemically-induced pulmonary hypertension. STUDY DESIGN: A miniature NO (mini-NO) generator was tested for its ability to produce therapeutic levels (20-80 parts per million (ppm)) of NO, while removing potentially toxic gases and metal particles. We studied healthy 6-month-old New Zealand rabbits weighing 3.4 ±â€¯0.4 kg (mean ±â€¯SD, n = 8). Pulmonary hypertension was induced by chemically increasing right ventricular systolic pressure to 28-30 mmHg. The mini-NO generator was placed near the endotracheal tube. Production of NO was triggered by a pediatric airway flowmeter during the first 0.5 s of inspiration. RESULTS: In rabbits with acute pulmonary hypertension, the mini-NO generator produced sufficient NO to induce pulmonary vasodilation. Potentially toxic nitrogen dioxide (NO2) and ozone (O3) were removed by the Ca(OH)2 scavenger. Metallic particles, released from the electrodes by the electric plasma, were removed by a 0.22 µm filter. While producing 40 ppm NO, the mini-NO generator was cooled by a flow of air (70 ml/min) and the external temperature of the housing did not exceed 31 °C. CONCLUSIONS: The mini-NO generator safely produced therapeutic levels of NO from air. The mini-NO generator is an effective and economical approach to producing NO for treating neonatal pulmonary hypertension and will increase the accessibility and therapeutic uses of life-saving NO therapy worldwide.

Comparative efficacy of endodontic medicaments and sodium hypochlorite against Enterococcus faecalis biofilms.

BACKGROUND: Many studies have investigated the effectiveness of root canal irrigants and medicaments against Enterococcus faecalis. The aim of this study was to compare the efficacy of commonly used medicaments against E. faecalis cultured as a biofilm on dentine substrate. METHODS: An E. faecalis biofilm was established on human dentine slices using a continuous flow cell. Each test medicament (Ledermix, Ca(OH)2 , Odontopaste, 0.2% chlorhexidine and 50:50 combinations of Ledermix/Ca(OH)2 and Odontopaste/Ca(OH)2 ) was introduced into the flow cell and biofilms were harvested and quantitated by determining cellular protein. Cellular viability was determined using serial plating and the number of colony-forming units was normalized against cellular protein to allow treatment protocols to be compared. Qualitative scanning electron microscopy analyses of the biofilm were performed after a 48-h exposure to each test agent. RESULTS: Sodium hypochlorite achieved total bacterial elimination. Ledermix and Odontopaste had no significant effect on the E. faecalis biofilm. Ca(OH)2 and 50:50 combinations of Ca(OH)2 /Ledermix or Ca(OH)2 /Odontopaste reduced the viability by more than 99% while 0.2% chlorhexidine reduced bacterial numbers by 97%. CONCLUSIONS: Sodium hypochlorite remains the gold standard for bacterial elimination in root canal therapy. However, Ca(OH)2 in isolation and combined with Ledermix, and Odontopaste was highly effective in reducing bacterial viability.

Inclusion of calcium hydroxide-treated corn stover as a partial forage replacement in diets for lactating dairy cows.

Chemical treatment may improve the nutritional value of corn crop residues, commonly referred to as corn stover, and the potential use of this feed resource for ruminants, including lactating dairy cows. The objective of this study was to determine the effect of prestorage chopping, hydration, and treatment of corn stover with Ca(OH)2 on the feeding value for milk production, milk composition, and dry matter intake (DMI). Multiparous mid-lactation Holstein cows (n = 30) were stratified by parity and milk production and randomly assigned to 1 of 3 diets. Corn stover was chopped, hydrated, and treated with 6% Ca(OH)2 (as-fed basis) and stored in horizontal silo bags. Cows received a control (CON) total mixed ration (TMR) or a TMR in which a mixture of treated corn stover and distillers grains replaced either alfalfa haylage (AHsub) or alfalfa haylage and an additional portion of corn silage (AH+CSsub). Treated corn stover was fed in a TMR at 0, 15, and 30% of the diet DM for the CON, AHsub, and AH+CSsub diets, respectively. Cows were individually fed in tiestalls for 10 wk. Milk production was not altered by treatment. Compared with the CON diet, DMI was reduced when the AHsub diet was fed and tended to be reduced when cows were fed the AH+CSsub diet (25.9, 22.7, and 23.1 ± 0.88 kg/d for CON, AHsub, and AH+CSsub diets, respectively). Energy-corrected milk production per unit of DMI (kg/kg) tended to increase with treated corn stover feeding. Milk composition, energy-corrected milk production, and energy-corrected milk per unit of DMI (kg/kg) were not different among treatments for the 10-wk feeding period. Cows fed the AHsub and AH+CSsub diets had consistent DMI over the 10-wk treatment period, whereas DMI for cows fed the CON diet increased slightly over time. Milk production was not affected by the duration of feeding. These data indicate that corn stover processing, prestorage hydration, and treatment with calcium hydroxide can serve as an alternative to traditional haycrop and corn silage in diets fed to mid-lactation dairy cows.

Haemolytic anaemia and hepatocitolysis associated with hypermagnesaemia by repeated exposures to copper-calcium fungicides.

For the medical practice, our manuscript acts as a signal, despite only presenting three cases which feature the association between hepatocytolysis, haemolysis and hypermagnesaemia. This clinical-biologic triad was highlighted with the workers who through the nature of their profession were exposing themselves periodically to vapours which contained copper sulphate neutralised with calcium hydroxide, a fungicide used for fruit trees. We are exclusively assessing the haematological perturbation. In this aetiological context, the generating mechanism for haemolysis is very probable biochemical, where hypercupraemia interferes with cellular antioxidant defence mechanisms. Hypothetically, the role of the redox homeostasis disorder in the intravascular destruction of erythrocytes is sustained, and particularly the coexistence of cell cytolysis in the medullary erythroid compartment, which can be assimilated with a possible ineffective erythropoiesis.

Disinfection of dentinal tubules with 2% Chlorhexidine gel, Calcium hydroxide and herbal intracanal medicaments against Enterococcus faecalis: An in-vitro study.

AIM: This in vitro study was conducted to evaluate the disinfection of dentinal tubules using 2% Chlorhexidine gel, Honey, Aloe vera gel, Curcuma longa, Propolis gel and Calcium hydroxide against Enterococcus faecalis. MATERIALS AND METHOD: Two hundred and ten human mandibular first premolars were infected with Enterococcus faecalis for 21 days. Samples were divided into 7 groups. Group I- Saline (negative control), Group II- 2% Chlorhexidine gel(CHX), Group III- honey, Group IV- Aloe vera gel, Group V- 20% Curcuma longa gel, Group VI- Propolis gel and Group VII -Calcium hydroxide (CH). At the end of 1, 3 and 5 days, the antimicrobial efficacy of medicaments against E.faecalis was assessed at the depths of 200µm and 400µm. RESULTS: 2% Chlorhexidine gel was most effective followed by Propolis and Curcuma longa. CONCLUSION: 2% Chlorhexidine gel gave the best results. Among the herbal extracts Propolis and Curcuma longa hold a promising future but to implement their use as sole intracanal medicaments clinically, further in vivo and long term studies are warranted.

Preference and usage of intracanal medications during endodontic treatment.

OBJECTIVES: To investigate the preferences of general dental practitioners (GDPs) and endodontists in using endodontic intra-canal medications (ICMs). METHODS: This observational and descriptive study was conducted in 2014 in the western province of Saudi Arabia. Following ethical clearance and 2 pilot studies, a web-based questionnaire was electronically sent to 375 randomly and systematically selected GDPs and all endodontists in the western province (n=49). An accompanying e-mail explained the study's aims and confirmed that the data yielded would remain confidential. The responses were collected, and the data was analyzed using the Chi-square test at p=0.05. RESULTS: Significantly, the highest proportion of respondents (53.7%) reported disinfection of the root canals as the main function of ICMs. Calcium hydroxide (CH) was the preferred material of the majority of those who used the same ICM in all cases (85.7%). While the vast majority of all endodontists (87.5%) used CH after pulp extirpation, 48.5% of GDPs used formocresol (p less than 0.001). Almost 30% of those who used ICMs after pulp extirpation did not do so after cleaning and shaping of vital cases. Most endodontists used CH (62.5%) and antibiotics (37.5%) in necrotic pulp cases without apical lesions, which were significantly greater than those of GDPs who did the same (43.8% and 17.2%). CONCLUSIONS: Participants were aware that the main function of ICMs is disinfection of the root canal system. However, it is clear that GDPs should reduce their reliance on phenol- and formaldehyde-based medications. There was a distinct trend toward the use of ICMs, especially CH, in necrotic pulp cases.

Single versus two visits with 1-week intracanal calcium hydroxide medication for endodontic treatment: One-year post-treatment results from a multicentre randomised controlled trial.

PURPOSE: To evaluate whether it is more effective to complete endodontic treatment in a single visit or in two visits with 1-week intracanal calcium hydroxide medication in symptomatic teeth and teeth with periapical lesions. MATERIALS AND METHODS: One hundred and ninety-nine patients, with one symptomatic tooth or a tooth with a periapical lesion, were randomised, according to a parallel group design, to receive a complete endodontic treatment in a single visit (99 patients) or in two visits with 1-week intracanal calcium hydroxide medication (100 patients), at two centres. Patients were followed for up to 1 year post-treatment and the outcome measures were tooth loss, radiographic healing, any complication, post-treatment pain and amount of painkillers used. RESULTS: Seven patients dropped out from the single-visit and ten patients from the two-visit group (all patients from one centre only). One patient lost his tooth from the single-visit and two patients from the two-visit group (difference in proportion = -0.01; 95% CI: -0.05 to 0.03; P = 0.619). Five single-visit patients and nine two-visit patients experienced one complication each (difference in proportion = -0.05; 95% CI: -0.12 to 0.03; P = 0.278). There were no statistically significant differences in tooth loss and complications. One year after treatment, complete radiographic healing was observed in 22 patients of the single-visit group and in 19 patients of the two-visit group; improvement in 43 patients of the single-visit group and in 54 patients of the two-visit group; and no changes/worsening in 24 patients of the single-visit group and in 15 patients of the two-visit group. There were no statistically significant differences in radiographic healing between the two groups (P = 0.509). Pre-treatment pain was reported by 68 single-visit patients and by 68 two-visit patients; 1-week post-treatment pain was reported by 27 single-visit patients and by 46 two-visit patients, and 2-week post-treatment pain was reported by 2 single-visit patients and 11 two-visit patients. For the first week, an average of 0.53 ±â€…1.23 tablets was taken by single-visit patients and 1.44 ±â€…3.32 tablets by two-visit patients. For the second week, no single-visit patients needed tablets and in the two-visit group the average was 0.37 ±â€…1.72 tablets. Patients of the two-visits group had statistically significant more post-treatment pain at 1 (P = 0.002) and 2 weeks (P = 0.011), and took more ibuprofen tablets at 1 (difference = -0.92; 95% CI: -1.62 to -0.21; P = 0.011) and 2 weeks after treatment (difference = -0.37; 95% CI: -0.72 to -0.03; P = 0.033), than in patients treated in a single visit. CONCLUSIONS: One year after treatment, both groups achieved similar clinical results; however, patients endodontically treated in a single visit suffered less postoperative pain and took less analgesics than patients treated in two visits, therefore a single-visit treatment should be recommended. Conflict-of-interest statement: This trial was self-funded and the authors have no conflict of interests to declare, however, rotary instruments were kindly provided by Sweden & Martina, Due Carrare PD, Italy.

Intracanal Irrigating Solutions Prior to Calcium Hydroxide Medication and Its Effects on Root Dentin Strength.

The aim of this study was to assess the effects of intracanal irrigation with sodium hypochlorite (NaOCl) and ethylenediaminetetracetic acid (EDTA) prior to calcium hydroxide medication on the compressive strength of root dentin. Forty-eight roots with single and straight canals were instrumented with a crown-down technique using Flexofile files and Gates Glidden burs, under 0.9% sodium chloride (NaCl) irrigation. Root canals were randomly separated into 4 groups (n=12), according to the irrigating solution: Control Group, 0.9% NaCl; GroupNaOCl, 1% NaOCl; GroupEDTA, 17% EDTA; and GroupEDTA+NaOCl, 17% EDTA and 1% NaOCl. Solutions remained for 40 min, renewed every 10 min, except for GroupEDTA+NaOCl, where the solutions were alternated every 10 min. Canals were dried and filled with calcium hydroxide paste, and radiographed. Each canal was sealed and stored at 37 °C for 30 days. After this period, the roots were cut 1 mm below the cementoenamel junction and 6 mm apically from this point in order to obtain 6 mm-long cylinders. The compressive test was conducted with a crosshead speed of 1 mm/min. The means (±SD) (MPa) of compressive strength were: Control Group, 151.23±94.36; GroupNaOCl, 167.50±57.25; GroupEDTA, 108.79±99.88; GroupEDTA+NaOCl, 60.12±92.10. Significant statistical differences among groups were found (ANOVA and Tukey, a=5%, p=0.02). Control Group and GroupNaOCl showed higher means of compressive strength than GroupEDTA+NaOCl. Intracanal irrigation with 17% EDTA and 1% NaOCl produced a significant reduction of dentin compressive strength 30 days after medication with calcium hydroxide.

Additive and reducing Effects between Calcium Hydroxide and Current Irrigation Solutions.

INTRODUCTION: Microorganisms should be considered to have the major role in starting and perpetuation of pulpo-periapical diseases. Using intracanal medicaments is necessary to gain a bacteria-free environment in the canal system. Calcium hydroxide (abbreviated as Ca(OH)2), which is the most commonly used medicament in endodontic therapy, has been shown to be effective against primary sources of infection; however, its effectiveness against some microorganisms, such as Candida albicans and Enterococcus faecalis has not been proved. On the other hand, sodium hypochlorite (NaOCl), chlorhexidine (CHX), and iodine potassium iodide (IKI) have been shown to be the potent medicaments against these microorganisms. Because of this fact, combination of Ca(OH)2 and some irrigants of the root canal has been suggested as potential intracanal medicaments. The aim of this literature review is to identify and address the efficacy of Ca(OH)2 in combined with some of these irrigating solutions.