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PubMed2003

Calcium hydroxide as an intracanal medication: effect on posttreatment pain.

Calcium hydroxide is advocated as an intracanal medication for various purposes, including prevention of posttreatment symptoms. This study assessed whether calcium hydroxide had a pain-controlling effect at different times when compared with no intracanal medication. One hundred forty patients participated. Conditions diagnosed were pulp/periapical pathosis with or without symptoms. At least partial cleaning and shaping was completed. At random, either Ca(OH)2 plus H2O paste or a dry cotton pellet was placed in the canals of half the teeth, respectively. All teeth were temporized with Intermediate Restorative Material. Patients assessed posttreatment pain up to 48 h as none, mild, moderate, or severe. The pain levels in each test group [Ca(OH)2 versus cotton pellet] at each time period were compared statistically with a multiple-regression analysis. There was no significant difference in posttreatment pain between the two groups at any time period or with any diagnosis or symptom. The use of calcium hydroxide as an intracanal medication was unrelated to the incidence and/or severity of posttreatment pain.

Adult↗
PubMed2004

Lack of genotoxicity of formocresol, paramonochlorophenol, and calcium hydroxide on mammalian cells by comet assay.

Formocresol, paramonochlorophenol, and calcium hydroxide are widely used in dentistry because of their antibacterial activities in root canal disinfection. However, the results of genotoxicity studies using these materials are inconsistent in literature. The goal of this study was to examine the genotoxic potential of formocresol, paramonochlorophenol, and calcium hydroxide using mouse lymphoma cells and human fibroblasts cells in vitro by the comet assay. Data were assessed by Kruskal-Wallis nonparametric test. The results showed that all compounds tested did not cause DNA damage for the tail moment or tail intensity parameters. These findings suggest that formocresol, paramonochlorophenol, and calcium hydroxide do not promote DNA damage in mammalian cells and that the comet assay is a suitable tool to investigate genotoxicity.

Analysis of Variance↗
PubMed2005

Endodontic therapy associated with calcium hydroxide as an intracanal dressing: microbiologic evaluation by the checkerboard DNA-DNA hybridization technique.

This study evaluated the predominant microbiota of infected necrotic pulps and the effects of calcium hydroxide therapy on these microorganisms by the checkerboard DNA-DNA hybridization technique. Conventional endodontic therapy associated with calcium hydroxide as intracanal dressing was performed in 12 single-rooted teeth with pulp necrosis and periradicular bone lesion. Samples were collected from the canal at baseline and 14 days after therapy, and the presence of 44 bacterial species was determined by the checkerboard method. Significant differences in the microbiota from baseline to post-therapy were sought by the paired-samples t test. The most prevalent species included F. nucleatum ss. vincentii, C. sputigena, C. ochracea, S. constellatus, V. parvula, P. gingivalis, P. melaninogenica, and S. sanguis. Most of the microorganisms were reduced after treatment, particularly A. gerencseriae, A. israelii, A. naeslundii, C. gingivalis, C. ochracea, P. gingivalis, S. noxia, S. sanguis, and S. oralis (p < 0.05). Conversely, A. actinomycetemcomitans, C. sputigena, and E. corrodens increased in numbers after therapy. These results indicate that conventional endodontic therapy with calcium hydroxide results in the reduction of pathogenic species associated with pulp necrosis. However, its use is limited, because it did not eliminate the whole spectrum of microorganisms.

Adult↗
PubMed1978

Effect of aluminium hydroxide and glycopyrrhonium on the absorption of ethambutol and alcohol in man.

1 The effect of aluminium hydroxide and/or of glycopyrrhonium on the absorption of a single oral 50 mg/kg dose of ethambutol (EMB) was investigated on thirteen tuberculous in-patients and on two groups of healthy volunteers with six subjects each. The EMB concentrations in serum and 10+h urine were measured by colorimetry. 2 In order to assess gastric emptying the healthy volunteers ingested ethanol, either 0.5 g/kg in 10% solution or 0.8 g/kg in 20% solution, simultaneously with the drug, and breath alcohol levels were measured repetitively. 3 Aluminium hydroxide significantly lowered the serum EMB levels of the patients during the first 4 h after the EMB intake. No consistent effect was found in the first student experiment, whereas in the second experiment aluminium hydroxide and glycopyrrhonium, alone or in combination, clearly retarded the EMB absorption. 4 Repeated breath alcohol analysis proved unsuitable to indicate the time course of gastric emptying in these circumstances.

Adult↗
PubMed1996

Calcium ion diffusion from calcium hydroxide-containing materials in endodontically-treated teeth: an in vitro study.

The aim of this in vitro study was to determine the amount and duration of diffusion of calcium ions from both a calcium hydroxide-containing root canal sealer and an intracanal medicament, through the apical foramen and the dentinal tubules of endodontically-treated teeth. The root canals of 88 freshly extracted single-rooted teeth were prepared using the modified double flared, balanced force technique with patency filing. The teeth were divided into four test groups of 20 teeth each and a control group of eight teeth. One group was dressed with a non-setting calcium hydroxide while the other was obturated using cold lateral condensation of gutta-percha with a calcium hydroxide-containing sealer. An artificial root defect was created in the apical third of the root of the teeth in the other two groups and the root canals were either dressed or obturated in the same way as the first two groups. All groups were incubated at 37 degrees C and were sampled for calcium diffusion after 1, 2 and 3 days and 1, 2, 3, 4 and 8 weeks. There was statistically significantly more calcium diffusion with the non-setting groups compared with the sealer groups (P < 0.05). There was more calcium ion diffusion from teeth with a patent apical foramen than those with an artificial resorptive root defect (P < 0.05).

Analysis of Variance↗
PubMed2005

Calcium release and pH-characteristics of calcium hydroxide plus points.

AIM: To evaluate calcium ion release and pH-characteristics of calcium hydroxide plus points (CHPP), conventional calcium hydroxide points (CHP, both Coltène/Whaledent, Langenau, Germany) and aqueous calcium hydroxide suspension (CHS) (Calxyl, OCO, Dirmstein, Germany). METHODOLOGY: Ten CHPP or CHP of size 50 were immersed into 5 mL isotonic sodium chloride solution. Conventional Ca(OH)2-free gutta-percha points served as negative control. Calcium release was measured up to 44 days by means of complexometric titration. Time dependent pH behaviour of all points in comparison with CHS was determined immersing 30 points of size 50 into 2.3 mL 0.9% wt NaCl-solution at time intervals of 0.5-72 h by a microelectrode measuring chain and a pH-meter. The surface morphologies of new and used gutta-percha points were evaluated qualitatively under a scanning electron microscope. Statistical evaluation was carried out using Kolmogorov-Smirnov-tests, Mann-Whitney-tests and multifactorial anova. RESULTS: For CHPP, a threefold greater calcium release was measured compared with CHP. Both types of points as well as CHS showed a maximum pH of approximately 12. Differences between groups were statistically significant for calcium release and pH (multifactorial anova; P < 0.001). Both types of points showed porous surfaces after usage, with a rougher surface for CHPP. CONCLUSIONS: CHPP and CHP increased the pH of isotonic sodium chloride >11 within 3 min. CHPP had a greater release of Ca2+ compared with CHP.

Analysis of Variance↗
PubMed2005

Calcium hydroxide dressings using different preparation and application modes: density and dissolution by simulated tissue pressure.

AIM: To study the effect of different apical shapes in prepared simulated root canals on the application of a commercially prepared calcium hydroxide paste by a syringe or lentulo spiral. METHODOLOGY: Three different types of root canal preparation were performed in 90 simulated canals: group A to an apical size 20 and a 0.10 taper using hand and rotary instruments, group B to an apical size 30 and a 0.08 taper using GT rotary instruments and group C to an apical size 40 and a 0.04 taper using ProFile 0.04 instruments. The insertion of calcium hydroxide [Ca(OH)2] paste was accomplished using either a lentulo spiral or a syringe. After 1 week of simulated fluid pressure applied to the apical end of the canal using physiological saline solution, the solution was evaluated for released Ca(OH)2. The specimens were weighed initially, after preparation, after insertion of Ca(OH)2 paste, after temporization with Cavit and after 1 week of simulated fluid pressure. Digital radiographs of the filled canals were taken and canal areas in mm2, gray values of the Ca(OH)2 dressings, total area of voids in mm2, as well as location of voids in the apical, middle or coronal thirds of the root canals were measured. Analyses of variance, with Scheffe's post-hoc tests, as well as chi-square tests were performed. RESULTS: Canals in group C had significantly fewer (P < 0.01) radiographic voids than canals in groups A and B. Using a lentulo spiral resulted in significantly (P < 0.05) fewer voids compared with the injection technique. More voids were detected coronally compared with middle and apical root canal thirds (P < 0.05). CONCLUSIONS: Canal shape and method of application had an impact on the amount and radiodensity of calcium hydroxide dressings in simulated root canals. Canals prepared to an apical size 40 and a taper of 0.04 had the least number of voids; Ca(OH)2 was placed with significantly fewer voids using a lentulo spiral compared with the injection technique.

Calcium Hydroxide↗
PubMed1993

Immunotherapy with aluminum hydroxide adsorbed insect venom extracts (Alutard SQ): immunologic and clinical results of a prospective study over 3 years.

This prospective study over 3 years investigated the safety, immunogenicity, and effectiveness of immunotherapy (IT) with aluminum hydroxide adsorbed insect venom extracts (Alutard SQ, ALK Laboratories) in patients with previous, severe, systemic, IgE-mediated, anaphylactic reactions to Hymenoptera stings. Seventeen patients were treated with honeybee venom (BV), 13 with yellow-jacket venom (YJV), and 5 with both. No severe reactions to IT were noted. Only 3 BV-allergic patients experienced mild systemic reactions of grades I or II (1 per 139 injections) during the increase phase. As for the immunologic data, there was a significant decrease in specific IgE antibodies after 1 year, and a significant increase in specific IgG and IgG4 antibodies on reaching the maintenance dose, with a further rise after 1, 2, and 3 years. Moreover, a significant decrease in anti-IgE autoantibodies was observed in the BV group. Out of the 11 patients that were occasionally restung by the relevant insect (totaling 19 stings in all), only one patient developed mild systemic allergic symptoms after a third sting. In view of these results, we consider IT with aluminum hydroxide adsorbed insect venom extracts to be safe, immunogenic, and effective. The low rate of side-effects may be due to the slow release of the venom in the aluminum hydroxide adsorbed form.

Adolescent↗
PubMed2004

Specific immunotherapy in honeybee venom allergy: a comparative study using aqueous and aluminium hydroxide adsorbed preparations.

BACKGROUND: For the immunotherapy of Hymenoptera venom allergy various preparations and treatment protocols are in use. However, controlled studies making direct comparisons of the efficacy and safety of different regimens are rare. OBJECTIVE: To assess prospectively different venom immunotherapy (VIT) protocols using an aqueous or an aluminium hydroxide adsorbed allergen preparation for the treatment of honeybee venom (HBV) allergy. METHODS: Sixty-five HBV allergic patients (42 males, 23 females; aged 17-75 years) with a history of systemic anaphylactic reactions (SARs) to honeybee stings were treated according to three different regimens. During the incremental phase, patients in group A (n = 21) or B (n = 21) received an aqueous preparation according to a rush protocol. Patients in group C (n = 23) were treated with conventional ("slow") VIT using an aluminium hydroxide adsorbed depot preparation. The maintenance dose was 100 microg venom in all groups. Maintenance treatment in group A was performed with the aqueous preparation administered every 4 weeks, whereas in groups B and C the depot preparation was administered every 8 weeks (group B) or every 4 weeks (group C). A sting challenge test with a living honeybee was performed in 49 patients, 6-12 months after reaching the maintenance dose. Another seven patients were stung accidentally by a honeybee ("field sting"). RESULTS: Treatment with the aqueous preparation evoked large local reactions more frequently than the depot preparation in the dose increase phase [53/693 (7.6%) vs 8/206 (3.9%); P = 0.059] and also in the course of maintenance therapy [85/172 (49.4%) vs 58/478 (12.1%); P < 0.001]. During the dose increase phase, systemic side-effects seemed to occur more frequently in patients on rush VIT with the aqueous preparation compared to patients initially treated with the conventional schedule using the depot preparation [13/42 (31.0%) vs 3/23 (13.0%); not significant). When re-stung by the culprit insect, SARs were observed in 3/20 patients (15.0%) in group A, 2/18 (11.1%) in group B and 3/18 (16.7%) in group C (not significant). CONCLUSIONS: The aluminium hydroxide adsorbed HBV preparation caused fewer large local reactions than the aqueous preparation. The therapeutic efficacy of the three treatment protocols did not differ.

Adolescent↗
PubMed1988

Alkalinization of peritoneal dialysis solutions with sodium hydroxide or sodium bicarbonate.

Peritoneal dialysis solution containing 1.5% dextrose was titrated with either sodium hydroxide or sodium bicarbonate. The titratable acidity was approximately 1.5 mmol/L as determined by sodium hydroxide titration. Generation of carbon dioxide on addition of sodium bicarbonate resulted in a titration curve that was shifted downward and to the right compared with the curve for sodium hydroxide addition. The information presented can be used to guide the amount of base to be added when partial or complete neutralization of peritoneal dialysis solution is desired.

Bicarbonates↗
PubMed1982

Primary mineralization of dentin in rats after pulp capping with calcium-hydroxide.

It has been previously reported that short term application of calcium-hydroxide to the dental pulp resulted in the formation of a dentin bridge with matrix vesicle calcification. The present study deals with the induction of reparative dentin in rat molar pulps by direct capping with calcium-hydroxide. The teeth were examined after 21 and 35 days. Transmission electron microscopy (TEM) revealed that the calcification process in the newly formed dentin was characterized by apatite deposition in matrix vesicles and the occurrence of calcifying nodules in the matrix. The persistence of these features of primary mineralization, during the experimental period, was associated with the continuous calcium hydroxide contact with pulp tissue, producing changes in its metabolic state.

Animals↗
PubMed1992

In vitro solubility of human pulp tissue in calcium hydroxide and sodium hypochlorite.

The tissue solvent capacity of a 2% stabilized sodium hypochlorite solution (Milton) and a commercial calcium hydroxide solution (Calasept) was examined under in vitro conditions where autolyzed human pulp fragments weighing approximately 0.0065 g were immersed in these solutions at 37 degrees C for periods of up to 10 days. It appeared that sodium hypochlorite was able to dissolve half the volume of pulp tissue within 1 h and the remaining tissue after 2-2 1/2 h. Calcium hydroxide dissolved half the pulp volume within 2 h, whereas it took 1 week for the remaining tissue to dissolve. These findings support the use of sodium hypochlorite as an irrigation solution during canal preparation and calcium hydroxide as a canal dressing for the purpose of creating a canal free of pulp remnants before root filling.

Calcium Hydroxide↗
PubMed1995

Evaluation of sealing ability, pH and flow rate of three calcium hydroxide-based sealers.

Three endodontic sealers containing calcium hydroxide (Sealapex, Sealer 26 and Apexit) and a zinc oxide-eugenol cement (Grossman's sealer) were examined for sealing ability, release of hydroxyl ions and flow rate. Dye penetration test was used to assess the sealing ability of the endodontic sealers. The pH test was accomplished to evaluate the release of hydroxyl ions from sealers and the pH readings were done at intervals of 30 min, 60 min and 7 days. In the flow test the sealers were placed between two glass slabs and a weight of 500 g was placed on the top of the glass. The diameters of the formed discs were recorded. The results revealed no statistically significant difference between apical seal provided by the four sealers. All of the calcium hydroxide based sealers alkalinized the surrounding medium. Sealer 26 cement presented significantly superior flow rate when compared with the other cements. These findings indicated that endodontic sealers containing calcium hydroxide presented satisfactory physicochemical properties when compared with a zinc oxide-eugenol sealer commonly used in endodontics.

Analysis of Variance↗
PubMed1995

Apical leakage following root canal dressing with calcium hydroxide.

The purpose of this study was to analyse the apical leakage in teeth filled by the lateral condensation technique following medication with calcium hydroxide. One hundred and twenty extracted human teeth were biomechanically prepared by using exclusively reaming motion with files up to #40. Half of the teeth received a calcium hydroxide dressing for 3 days. The medication was removed by irrigation and reaming motion with files #40 up to #70. The teeth were divided in 6 experimental groups, according to the dimension of the utilized instrument. The root canals were filled and posteriorly the teeth were placed into a 2% methylene blue dye solution inside a flask, which was attached to a vacuum pump. Leakage was measured linearly, and the results showed significantly (p<0.01) less leakage in the experimental groups that received calcium hydroxide dressings than in the control groups. The results persisted even after the removal of 300 micrometers of dentin from the root canal dentinal walls.

Analysis of Variance↗
PubMed1997

Effect of calcium hydroxide dressing on seal of permanent root filling.

Low apical leakage along root fillings following an application of calcium hydroxide was reported in a few methylene blue dye penetration studies. It has been found recently that methylene blue is decolored by calcium hydroxide, indicating that the short penetration of methylene blue may not be due to a tight seal only. Of the 80 roots of human maxillary central incisors used in this study, 40 roots (group 1) received calcium hydroxide root canal dressing whereas another 40 roots (group 2) did not. All the roots were then obturated with gutta-percha and Tubli-Seal sealer. Leakage along 20 filled roots in each group was measured using a modified fluid transport model at 48 h, 2, 4, 8 and 16 weeks after obturation; whereas leakage of another 20 filled roots in each group was measured using dye penetration with 1% methylene blue. Using the fluid transport model, no significant difference was found between the two groups at any time interval (P = 0.4847, 0.3875, 0.9490, 0.4786, 0.9148 respectively after 48 h, 2, 4, 8 and 16 weeks); using the methylene blue penetration method, leakage in group 1 (with root canal dressing) was significantly less than that in group 2 (without root canal dressing) (P = 0.0374). The contradiction in results from the different models indicated that problems existed with the models.

Calcium Hydroxide↗
PubMed1999

Clinical evaluation of glutaraldehyde with calcium hydroxide and glutaraldehyde with zinc oxide eugenol in pulpotomy of primary molars.

The objectives of this study were to clinically evaluate the effectiveness of 2% buffered glutaraldehyde in pulpotomies of human primary molars and to compare the success rate of glutaraldehyde with calcium hydroxide and glutaraldehyde with zinc oxide eugenol as dressing material on the radicular pulp. Pulpotomies were completed on 61 primary molars in 19 children. The teeth were divided into two groups by random allocation. One group had a dressing of zinc oxide-eugenol base (IRM) incorporated with one drop of 2% buffered glutaraldehyde while the other group had a dressing of calcium hydroxide base incorporated with one drop of 2% buffered glutaraldehyde after the initial placement of 2% buffered glutaraldehyde on cotton pellet for 3 min. All teeth had light-curing compomer (Dyract) placed over the dressing material followed by a stainless steel crown restoration within 1 or 2 weeks after the pulpotomy. Blind clinical and radiographic evaluations of 57 teeth available after 12 months showed a success rate of 92.9% and 73.6% respectively. The clinical and radiographic success rates for glutaraldehyde/zinc oxide eugenol pulpotomies were 96.5% and 75.8% respectively while those for glutaraldehyde-calcium hydroxide were 89.2% and 71.4%. There was no statistically significant difference between the two groups either clinically or radiographically. The overall clinical success rate suggested that 2% buffered glutaraldehyde was an effective agent in the pulpotomy of human primary molars.

Calcium Hydroxide↗
PubMed2003

An experimental study on the vasoconstriction effect of calcium hydroxide using rat mesentery.

Calcium hyroxide has been used for eliminating persistent intracanal exudation. In order to address the mechanism behind this action, we investigated whether calcium hydroxide solutions cause the constriction of microvessels in the mesenteric microcirculation bed of rats. The exteriorised mesentery from anaesthetised rats was spread in a chamber, and arterioles, venules and capillaries were viewed under a digital microscope. Various concentrations of calcium hydroxide solutions were applied for 10 sec, and the diameter of the microvessels was recorded. In arterioles, calcium hydroxide solutions caused rapid and transient constriction. A statistically significant difference versus original diameter was detected 1 min after the application of 4.0 x 10(-3) mol/l and 1.0 x 10(-2) mol/l solutions (p < 0.05, one-way analysis of variance and Tukey-Kramer test). No statistically significant constriction occurred in capillaries and venules. It was concluded that the arteriolar constriction might be an explanation for the exudation-controlling effect of intracanal calcium hyroxide dressings.

Analysis of Variance↗
PubMed1982

Characterization and aqueous extraction of calcium hydroxide materials.

Analysis of two single and eight dual product systems showed the former to be calcium hydroxide dispersed in an aqueous gel in methyl ethyl ketone solution of an acrylic polymer and the latter were cements based on the polymerization occurring when mixing salicylate esters with calcium hydroxide. Using water as an extractant under controlled conditions, specimens of the prepared materials produced marked differences in pH values over 24 hours and conductivity over 72 hours; also cumulative extractions over 26 weeks showed substantial variation in the amount of calcium hydroxide and other solubles.

Calcium Hydroxide↗