Grossman's Sealer Research Articles

Zinc Oxide Nanoparticles Enhance Physicochemical Characteristics of Grossman Sealer

IntroductionMetallic antibacterial nanoparticles have been shown to provide distinct antibacterial advantage and antibiofilm efficacy when applied in infected root canals. The purpose of this study was to evaluate the influence of incorporating zinc oxide nanoparticles (ZnO-Np) on the physicochemical properties of Grossman sealer. MethodsGrossman sealer was prepared according to its original formula. Additionally, 4 experimental sealers were prepared by replacing the zinc oxide component of the powder with ZnO-Np (average size of 20 nm) in different amounts (25%, 50%, 75%, and 100%). Characterization of the setting time, flow, solubility, dimensional changes, and radiopacity were performed according to American National Standards Institute (ANSI)/American Dental Association (ADA) Specification 57. Scanning electron microscopic and energy-dispersive X-ray spectroscopic analyses were conducted to assess the ultrastructural and chemical characteristics of experimental sealers subjected to the solubility test. Statistical analyses were performed with analysis of variance and post hoc Tukey-Kramer tests with a significance level of 5%. ResultsA statistically significant difference in the setting time was observed among groups (P < .05), but only 25% ZnO-Np sealer complied with ANSI/ADA requirements. There was a significant difference in the flow characteristics between the control and 25% and 75% ZnO-Np experimental sealers (P < .05), but all sealers conformed to ANSI/ADA standardization; 25% ZnO-Np sealer showed significantly less solubility (1.81% ± 0.31%) and dimensional change (−0.34% ± 0.12%) than other sealers (P < .05). All sealers showed ultrastructural changes with increasing solubility. ConclusionsZnO-Np decreased the setting time and dimensional changes characteristic of Grossman sealer; 25% ZnO-Np improved the physicochemical properties of Grossman sealer in accordance with ANSI/ADA requirements.

Evaluation of apically extruded debris during endodontic retreatment

A growing interest to preserve teeth into the mouth by patients resulted in the increasing number of endodontic retreatments, and when these happen, many different types of irritants are extruded through the foramen. Objective: This study analyzed in vitro the amount of debris extruded through the foramen using four instrumentation techniques during endodontic retreatment. Material and methods: Forty mesial-buccal roots of first molars were selected, instrumented with anatomical diameter up to size #30 ISO file and then obturated with gutta-percha and grossman sealer by lateral condensation. After, they were separated and randomly allocated into four groups with 10 teeth each for the endodontic retreatment procedure: G1 – conventional technique + solvent, G2 – conventional technique without solvent, G3 – ProTaper retreatment + solvent, G4 – ProTaper retreatment without solvent. In all groups, gutta-percha in the coronal portion was removed by using size 1-3 Gates Glidden drills. All teeth were irrigated with distilled water. The debris extruded through the foramen were collected and weighed by an analytical balance. Results: Group 4 had the lowest average for material extrusion through the foramen followed by groups 2, 3 and 1. When Tukey test for statistical analysis was applied, no significant difference among groups were found (p = 0.5664). Conclusion: We conclude that all instrumentation techniques used in this study produced debris which goes beyond the foramen.

Reaction of Rat Subcutaneous Connective Tissue to a Mineral Trioxide Aggregate–based and a Zinc Oxide and Eugenol Sealer

IntroductionThe purpose of this study was to evaluate the subcutaneous connective tissue reaction in rats to a mineral trioxide aggregate (MTA)-based endodontic sealer Fillapex (Angelus, Londrina, PR, Brazil) and compare it with Grossman sealer (Farmadental, Buenos Aires, Argentina). MethodsSterile medical-grade silicone tubes containing the test materials were implanted in 24 Wistar rats. After 10, 30, and 90 days, the animals (n = 8 per period) were euthanized, and the implants along with their surrounding tissues were dissected, fixed, and processed for histologic evaluation. A 4-category evaluation system was used to evaluate the microscopic observations. The tissue response on the lateral walls of the silicone tubes was used as the negative control. The data were analyzed for statistical significance using the Wilcoxon signed rank, Kruskal-Wallis, and Dunn tests. ResultsFillapex showed a severe tissue reaction for all 3 observation periods. Grossman sealer showed similar features after 10 and 30 days, but the reaction decreased slightly after 90 days. In contrast, the negative controls did not show adverse reactions in any sample of the 3 time periods. After 10 and 30 days, no statistically significant differences were found between Fillapex and Grossman sealer (P > .05); however, the difference was significant after 90 days (P < .05). For all experimental periods, there were statistically significant differences between both Fillapex and Grossman sealer and the negative controls (P < .05). ConclusionsIt was concluded that both MTA-Fillapex and Grossman sealer remained toxic to subcutaneous tissues in rats after 90 days.

Effect of root canal filling materials on dimensions of cone-beam computed tomography images

Objective To evaluate the discrepancy of root canal filling (RCF) measurements obtained from original root specimens and cone-beam computed tomography (CBCT) images. Material and Methods Seventy-two human maxillary anterior teeth were prepared up to an ISO #50 K-File 1 mm short of the apical foramen. Thus, the teeth were randomly divided into 8 groups, according to the root canal filling material: Sealapex®, Sealapex®+gutta-percha points, Sealer 26®, Sealer 26®+gutta-percha points, AH PlusTM, AH PlusTM+gutta-percha points, Grossman Sealer, and Grossman Sealer+gutta-percha points. After root canal preparation and RCF, CBCT scans were acquired and the specimens were sectioned in axial, sagittal and coronal planes. The RCF measurements were obtained in different planes and thicknesses to determine the discrepancy between the original root specimens (using a digital caliper) and the CBCT images (using the scanner's proprietary software). One-way analysis of variance and Tukey tests were used for statistical analyses. The significance level was set at α=5%. Results Measurements of the different endodontic filling materials were 9% to 100% greater on the CBCT images than on the original root specimens. Greater RCF dimensions were found when only sealers were used, with statistically significant difference among the groups. Conclusions RCF dimensions were greater on CBCT images than on the original root specimens, especially when only sealer was used.

Bond strength of different endodontic sealers to dentin: push-out test

ObjectiveThe aim of this in vitro study was to evaluate the bond strength of different root canal sealers to dentin. Material and MethodsForty extracted single-rooted human teeth were examined and the coronal and middle thirds of the canals were prepared with a 1.50 mm post drill (FibreKor Post System, Pentron). The teeth were allocated in two experimental groups, irrigated with 2.5% NaOCl+17% EDTA or saline solution (control group) and instrumented using Race rotary files (FKG) to a size #40 at the working length. Then, the groups were divided into four subgroups and filled with Epiphany sealer (Group 1), EndoREZ (Group 2), AH26 (Group 3) and Grossman's Sealer (Group 4). After 2 weeks of storage in 100% humidity at 37ºC, all teeth were sectioned transversally into 2-mm-thick discs. Push-out tests were performed at a cross-head speed of 1 mm/min using a universal testing machine. The maximum load at failure was recorded and expressed in MPa. ResultsMeans (±SD) in root canals irrigated with 2.5% NaOCl and 17% EDTA were: G1 (21.6±6.0), G2 (15.2±3.7), G3 (14.6±4.5) and G4 (11.7±4.1).Two-way ANOVA and Tukey's test showed the highest bond strength for the Epiphany's group (p< 0.01) when compared to the other tested sealers. Saline solution decreased the values of bond-strength (p<0.05) for all sealers. ConclusionEpiphany sealer presented higher bond strength values to dentin in both irrigating protocols, and the use of 2.5% NaOCl and 17% EDTA increased the bond strength values for all sealers.

Effectiveness of a silicon-based root canal sealer for filling of simulated lateral canals

The purpose of this in vitro study was to evaluate the ability of a silicon-based root canal sealer, compared to zinc oxide and eugenol and an epoxy resin-based sealers, for filling of simulated lateral canals. Thirty extracted single-rooted human teeth were selected, conventional access was made and the working length was established 1 mm from the apical foramen. Three simulated lateral canals, one in each root third (coronal, middle and apical) were prepared in both the mesial and distal surfaces of each tooth using a size 15 reamer adapted to a low-speed handpiece. Each root canal was instrumented using ProTaper rotary files up to file F3 at the working length, and then irrigated with 2.5% NaOCl followed by EDTA. The teeth were assigned to 3 groups (n=10), according to the root canal sealer: Roeko Seal (Group 1), Sealer 26 (group 2) and Grossman's sealer (Group 3). Gutta-percha cold lateral condensation technique was performed in all groups. Postoperative radiographs were taken and the images were projected for evaluation of the quality of lateral canal filling. Data were submitted to statistical analysis by Kruskal Wallis test at 5% significance level. The results showed that Grossman's sealer filled a larger number of lateral canals than Roeko Seal (p<0.05) and Sealer 26 (p<0.01). It may be concluded that Roeko Seal silicone-based root canal sealer was not as effective as the Grossman's sealer for filling of simulated lateral canals. The lateral canals localized in the apical third of the root were more difficult to be filled.

A study of the rheological properties of endodontic sealers

To test the hypothesis that there would be no statistically significant difference in viscosity-related measures of endodontic sealers or change in these with strain rate, internal diameter or powder : liquid ratio in a capillary system. Materials used were Apexit, Tubliseal EWT, Grossman's sealer and Ketac-endo. Viscosity-related measures were tested in a two-plate test, and in a capillary rheometer. The mean values (n = 12) for thickness and diameter of material formed between two glass plates were tested with one-way analysis of variance. Pressure was applied to a capillary rheometer at strain rates 5 and 10 mm min(-1) in tubes of internal diameter 0.6 and 1.2 mm. Tubliseal EWT had a thinner film thickness than the other sealers (alpha = 0.05). The difference in diameter between Tubliseal EWT and the other sealers was significant apart from Apexit. Increased strain rate gave a significant increase (alpha = 0.05) in the flow of all sealers. Narrower tubes produced increased velocity, which was significant for all sealers, and reduced volumetric flow, which was significant for all sealers except Grossman's 2 : 1 (Wilcoxon signed rank test). Reduction in powder : liquid ratio of Grossman's significantly increased flow in narrow tubes and at higher strain rate (Mann-Whitney test). There was a significant difference between the flow of Tubliseal EWT and the other sealers tested in the two-plate test; capillary flow was affected by sealer, internal diameter, strain rate and powder : liquid ratio. The null hypotheses were rejected.

Short‐term antibacterial activity of root canal sealers towards Enterococcus faecalis

To investigate the antimicrobial activity of root canal sealers on Enterococcus faecalis, either allowing or avoiding direct contact between sealers and bacteria. Filter paper discs were immersed in standardized E. faecalis suspensions and exposed to freshly mixed sealers (MCS, AH Plus, Grossman's sealer, Sealapex, Apexit) in teflon wells for 30 min, with or without a filter membrane placed between filter paper discs and sealers (membrane-restricted contact test and direct contact test, respectively). After exposure, the filter paper discs were transferred to vials containing phosphate-buffered saline (PBS) and glass beads, and vigorously vortexed. PBS with resuspended bacterial cells was serially diluted and 25 microL droplets were seeded on TSA plates. The plates were incubated in air at 37 degrees C for 24 h and colony-forming units were counted. Using alpha = 0.05 as level for statistical significance, the data obtained were analysed using Student's t-test. In the direct contact test, MCS and AH Plus killed the bacteria to a level below the detection limit. They were followed in decreasing order of efficacy by Grossman's sealer, Sealapex and Apexit. In the membrane-restricted contact test, the sealers ranked: MCS, AH Plus, Grossman's sealer, Apexit and Sealapex, in descending order of antibacterial potency. MCS, AH Plus and Grossman's sealer significantly reduced the number of viable bacteria in both tests. Sealapex and Apexit were not statistically different from control. MCS, AH Plus and Grossman's sealer were effective in reducing the number of cultivable cells of E. faecalis. Calcium hydroxide-based sealers, Sealapex and Apexit were ineffective in this short-term experiment.

The pH Changes of Four Different Root Canal Sealers After Mixing at Various Time Intervals in vitro

The purpose of this study was to compare the surface pH level of four different type sealers after mixing at various time intervals in vitro. After cleaning and shaping root canals in 50 recently extracted, single-rooted human teeth, they were divided into six groups. Each of four groups was obturated with Apexit, N2, Sealapex, and Grossman sealers. The remaining groups served as controls. In group 1 nothing was added to the vial of saline solution. In group 2 canals had been instrumented but not obturated with sealer. The pH level of saline solutions was determined at intervals of 1 hour, 4 hours, 1 day, 2 days, 3 days, 1 week, and 4 weeks after teeth were placed in them. The pH levels of the five solutions were compared to each other and to that of saline solution only.

Adhesion of Endodontic Sealers: Scanning Electron Microscopy and Energy Dispersive Spectroscopy

The microscopic details of the debonded interfaces between endodontic sealers and dentin or gutta-percha were assessed in this study. Dentin, conditioned with 37% H3PO4 for 30 s, 25% citric acid for 30 s, 17% EDTA for 5 min, or a rinse with 10 ml of distilled H2O (control), and gutta-percha surfaces were coated with freshly mixed sealer: Grossman's sealer, Apexit, Ketac-Endo, AH Plus, RoekoSeal Automix, or RoekoSeal Automix with an experimental primer. The surfaces were pressed together and the sealers were allowed to set. After tensile bond strength testing, the morphological aspects of the fractured surfaces were assessed by scanning electron microscopy and energy dispersive spectroscopy. The energy dispersive spectroscopy successfully traced sealer components to the debonded surfaces. Some of the sealers penetrated into the dentinal tubules when the dentin surface had been pretreated with acids. However, these sealer tags remained occluding the tubules after bond failure in some instances only (Grossman's sealer, RoekoSeal Automix with an experimental primer, AH Plus/EDTA). Penetration of the endodontic sealers into the dentinal tubules when the smear layer was removed was not associated with higher bond strength.

A new silicon-based root canal sealer (Roekoseal-Automix).

This study evaluated the new silicon-based sealer 'Roekoseal-Automix' (RSA) with respect to sealing, bonding capabilities and biocompatibility with rat subcutaneous connective tissue. For the microleakage study, 36 single rooted teeth were instrumented and 30 of these obturated with either Grossman's sealer or RSA using lateral condensation technique (15 of each). Six teeth were not obturated and used as control group. For investigating bonding capability, 10 of the obturated roots with RSA and Grossman's sealer were ground and split longitudinally and examined by scanning electron microscopy (SEM). The RSA was found to seal significantly better than Grossman's sealer. The SEM examination revealed a good bond between RSA and the dentine and between RSA and the gutta-percha. Tissue reaction was evaluated by injecting 0.1 mL RSA into the connective tissue of 21 male Albino-Wistar rats and observing at 24 h, 7 days and 30 days and 30 days. Formation of a new granulation tissue with fibrous tissue adjacent to the material at 30 days. This study found that RSA performed well.

Adhesion of a glass-ionomer root canal sealer to human dentine.

This in vitro study evaluated the effect of smear layer removal on adhesion to human dentine of Ketac-Endo, Grossman, and Sealer 26 root canal sealers. A total of 60 extracted human maxillary and mandibular molars with their crowns ground flat were used. The teeth were divided into two groups: Group 1, the dentine surface received no treatment; Group 2, EDTA-C was applied to the dentine surface for 5 min. Ten samples were tested for each sealer and each group. Adhesion was measured with a Universal Testing Machine. Sealer 26 showed greater adhesion both with and without smear layer (p < 0.01). Ketac-Endo and Grossman sealers were statistically equal, having the lowest values of adhesion. Application of EDTA-C did not alter the adhesion of Ketac-Endo and Grossman sealers. However, the use of EDTA-C increased the adhesion of Sealer 26. The epoxy resin-based root canal sealer (Sealer 26) adhered better to dentine prepared with and without EDTA-C than glass-ionomer-based sealers and the zinc oxide eugenol-based (Ketac-Endo and Grossman) sealers.

Antimicrobial Activity and Flow Rate of Newer and Established Root Canal Sealers

Endodontic sealers that possess both optimum flow ability and antimicrobial properties may theoretically assist in the elimination of microorganisms located in confined areas of the root canal system. The antimicrobial effects and the flow rate of the following sealers were investigated and compared: Kerr Pulp Canal Sealer EWT, Grossman's Sealer, ThermaSeal, Sealer 26, AH Plus, and Sealer Plus. The agar diffusion test was used to assess the antimicrobial activity of the sealers. In the flow assay, 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. All root canal sealers tested showed some antimicrobial activity against most of the microorganisms. There were no significant differences between the materials tested (p > 0.05). All root canal sealers also flowed under the conditions of this study. Statistical analysis of the results revealed that AH Plus and Kerr Pulp Canal Sealer EWT had flow values significantly superior to the other sealers tested (p > 0.05). Taken together, these findings suggest that these sealers have the potential to help in the microbial control in the root canal system.

Effects of root canal sealers on immunocompetent cells in vitro and in vivo.

Over the years of testing biocompatibility of endodontic filling materials, little attention has been paid to the potential adverse influences on the function of the immune system. Therefore, the purpose of this study was to investigate the extent to which extractable components of some commonly used root canal sealing materials (ERCS) may interfere with immunocompetent cells in vitro. The potential of these materials to cause delayed-type hypersensitivity (DTH) was also addressed in a rat model system. Extractable components were drawn in cell culture medium from freshly mixed or set material of AH 26. Grossman's sealer, Endomethasone, and Apexit. In-vitro assays included either spleen cells or rat pulp tissue cells that were released following enzymatic digestion with collagenase. Purified T cells for the pulpal cell assay were obtained from rat mesenteric lymph nodes. The effect of ERCS on the proliferation of concanavalin A (con A) stimulated spleen cell was measured by 3H-thymidine incorporation. Pulpal accessory cell function was monitored by the capacity of pulpal cells, pretreated with components of ERCS, to provide signals to con A stimulated T cells. DTH was tested after subcutaneous implantation of root canal sealers (RCS) in rats and challenge by ear injection. Pretreatment of pulpal cells with low dilutions of eluates from extracted AH 26 and Endomethasone resulted in a strong reduction of the T cell proliferation rate. The effect was considerably reduced (P < 0.01) when extracts of the solid material were employed. Extracts of Grossmans' sealer and Apexit affected T cell proliferation only to a limited extent in the pulpal cell assay. In general, assays on spleen cells showed a similar profile, although increased cell division was induced by Grossman's sealer at high eluate dilutions and a concentration-dependent decrease of cell division at lower concentrations of this material. ERCS evoked both immunosuppression and, in some instances, immunostimulation, but they did not release DTH.

Dowel space preparation in root canals filled with glass ionomer cement

The aim of this study was to evaluate post space preparation difficulties in canals filled with Ketac Endo and with Grossman's sealer. Sixty-three single-rooted teeth were prepared using a step-back technique and were divided into four groups: group 1--canals were irrigated with 25% tannic acid and filled with Ketac Endo and a single-cone technique; group 2--canals were irrigated with 1% sodium hypochlorite and fillings done as in the previous group; group 3--canals were irrigated with 25% tannic acid and filled with Ketac Endo and one gutta-percha cone previously adapted with chloroform; and group 4--canals were irrigated with 1% sodium hypochlorite and filled with Grossman's sealer and a lateral condensation technique. After 72 h, canals post space were prepared using Peeso drills. The time required was measured in seconds and analyzed by Tukey multiple comparison test (level 5%). Post space preparation time for groups 1 to 3 was longer than for group 4 and longer for group 1 than for groups 2 to 4.

Evaluation of glass ionomer as an endodontic sealant: An in vitro study

This study investigated the sealing ability of glass ionomer as a root canal sealer with and without lateral condensation of gutta percha cones. Ten gutta percha cones were embedded in Grossman's sealer and 10 in glass ionomer sealer. The sealers were mechanically separated from the gutta percha. The cone surfaces were examined using scanning electron microscopy (SEM). SEM revealed a characteristic etch pattern on the glass ionomer group and a hybrid layer on the cone surfaces of the Grossman's group. Additionally, 40 maxillary incisors were divided into four treatment groups: 1) glass ionomer sealer with lateral condensation, 2) glass ionomer sealer with only one master cone, 3) Grossman's sealer with condensation, and 4) Grossman's sealer with only one master cone. The average values for leakage (mm) in groups 1 through 4 were 0.81 +/- 0.75, 4.30 +/- 1.82, 0.67 +/- 0.80, and 1.10 +/- 1.68, respectively. Statistical analysis showed that group 2 leaked more than the other three groups.

Ultrasonic preparation and obturation of root‐end cavities

This study evaluated the preparation of root-end cavities using an ultrasonically activated file, and the obturation of such cavities. In the first part, the root canals of 40 extracted teeth were prepared to size 40 and irrigated with NaOCl and EDTA. The root ends were resected and the teeth inoculated with Enterococcus faecalis, incubated for 10 days and divided into four groups: control; saline; irrigation; hand instrumentation performed via a retrograde approach up to size 50 using saline irrigant; ultrasonic instrumentation with prebent size 40 K-flex file inserted into a Piezon Master using saline irrigant. The teeth were fixed, sectioned longitudinally and viewed under scanning electron microscopy. Bacterial and smear layer scores were obtained at 1, 3, and 5 mm from the resected end. The bacterial scores for control and saline groups were similar; the scores for each instrumentation group were significantly lower than the control group (P<0.001). In addition, there were significantly fewer bacteria in the ultrasonic group compared with the hand instrument group (P<0.001). The smear layer scores for control and saline groups were similar, and significantly lower than in either instrumentation group (P<0.001). In the second part, root-end cavities were ultrasonically prepared in 20 extracted teeth. Ten cavities were filled with amalgam, and 10 with thermoplasticized gutta-percha and Grossman's sealer. After 24-h storage, the root ends were immersed in dye for 48 h. Cross-sectional slices of the obturated part of the root were evaluated using both light and confocal microscopy for dye leakage along the interface of filling material and dentine. There were no statistical differences between the leakage of amalgam and gutta-percha root-end fillings, nor between the two methods of microscopy.

Comparison of apical leakage between Ketac Endo sealer and Grossman sealer

Forty-eight extracted human teeth were prepared for study to compare ketac Endo cement with Grossman's cement in preventing leakage of a dye. Four groups were formed: (1) Grossman's sealer with a single gutta percha cone; (2) Grossman's sealer with lateral condensation of gutta percha; (3) Ketac Endo sealer with a single cone of gutta percha; and (4) Ketac Endo sealer with lateral condensation of gutta percha. The teeth were immersed in the dye for 10 days, after which they were rinsed in running tap water and cleared for observation. In the groups of teeth evaluated by three individual evaluators, the results consistently showed less leakage with glass ionomer sealers (groups 3 and 4) than with the Grossman's sealers (groups 1 and 2). The best results were noted when Ketac Endo sealers were used with lateral condensation.

Depth of penetration and appearance of grossman sealer in the dentinal tubules: An in vivo study

Five teeth extracted after chemomechanical preparation (group A) and 11 extracted 1 to 7 yr after endodontic treatment (group B) were selected for this study. A 1% NaOCl was used for irrigations and a lateral condensation technique with a Grossman-type sealer was used for obturation. The teeth were fractured and prepared for and viewed by a scanning electron microscope equipped with an electron dispersive spectrometer. All root canal walls of group A were covered with a thick smear layer. Sealer, either rod-like or granular in appearance and barium free, was present in the majority of the dentinal tubules of group B usually at a distance up to 200 microns from the root canal walls; in two cases up to 900 microns. Sealer was found deepest in the middle third of the root. The smear layer did not stop sealer from entering the dentinal tubules. The differences in the depth of penetration or in the appearance of the sealer cannot be attributed to the different time periods the teeth remained in the arch after endodontic treatment.

A histological comparison of periapical inflammatory and neural responses to two endodontic sealers in the ferret

Previous studies have shown that there is a proliferation of nerves beneath the apices of pulpectomized teeth. This may be due to the inflammation induced after the procedure, resulting, perhaps, from the irritant nature of the materials used to fill the root canal. The experiment reported here was conducted to determine whether this inflammation was induced by the sealer rather than arising as a result of tissue damage and whether, if inflammation is eliminated or reduced, the neural changes are also reduced. In 12 young adult ferrets under general anaesthesia the pulps of the lower canine teeth were removed and replaced with gutta percha and sealer. A sealer of Grossman's formulation with eugenol as the liquid phase was used on one side and a calcium hydroxide sealer that contained no eugenol on the other. Three months later the animals were, again under general anaesthesia, perfused with a fixative mixture. The mandibles were removed and the presence and size of any periapical inflammatory lesions and the density of periapical innervation determined histologically. All 12 teeth sealed with the Grossman's sealer had inflammatory lesions at their apices. Three of the 12 teeth treated with the calcium hydroxide sealer showed similar lesions. In all the teeth with inflammatory lesions the normal arrangement of nerves in a periodontal ‘plexus’ was disrupted but there was no statistically significant difference between the overall innervation density in inflamed and non-inflamed periapical areas nor between areas beneath teeth sealed with Grossman's sealer and with calcium hydroxide. The incidence of periapical inflammation is related to the nature of endodontic sealer used. The pattern but not the quantitative extent of the periapical innervation is related to the presence of inflammation.