Effect of post space preparation on apical seal: influence of time interval and sealer.

Med Oral Patol Oral Cir Bucal. 2007 Oct;12(6):E464-8

Authors: Corrêa Pesce AL, González López S, González Rodríguez MP

OBJECTIVE: To assess the efficacy of two sealants to preserve the apical seal after root canal preparation and cementation of posts at 24 h or 72 h after endodontic treatment. STUDY DESIGN: Sixty human single-root teeth were instrumented and obturated using lateral compaction technique with EndoFill [30] or AH-Plus) [30] and were prepared in one of three ways, leaving a 3 mm gutta percha remnant in all cases: without cast post preparation, with preparation after 24 h or after 72 h. After cementing the posts, the specimens were thermal cycled at 5 and 55 degrees C in water baths, submerged in 2% methylene blue dye for 72 h, embedded in acrylic resin and cut transversally into three 1-mm apical sections. Dye leakage was quantitatively assessed as the percentage leaked area. RESULTS AND CONCLUSION: Comparison of the apical sections showed significant differences in leakage with both sealers among the three preparation groups (p<0.001). No significant differences between sealers were found in any preparation group or in the same sections.

PMID: 17909515 [PubMed - indexed for MEDLINE]

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

Braz Dent J. 2007;18(1):20-3

Authors: Barbizam JV, Souza M, Cecchin D, Dabbel J

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.

PMID: 17639195 [PubMed - indexed for MEDLINE]

Residual antibacterial activity of chlorhexidine digluconate and camphorated p-monochlorophenol in calcium hydroxide-based root canal dressings.

Braz Dent J. 2007;18(1):8-15

Authors: Soares JA, Leonardo MR, Tanomaru Filho M, Silva LA, Ito IY

The purpose of this study was to evaluate the residual antibacterial activity of several calcium hydroxide [Ca(OH)2]-based pastes, placed in root canals of dogs' teeth with induced chronic periapical lesions. Root canals were instrumented with the ProFile rotary system and filled with 4 pastes: G1 (n=16): Ca(OH)2 paste + anesthetic solution; G2 (n=20): Calen paste + camphorated p-monochlorophenol (CMCP); G3 (n=18): Calen; and G4 (n=18): Ca(OH)2 paste + 2% chlorhexidine digluconate. After 21 days, the pastes were removed with size 60 K-files and placed on Petri plates with agar inoculated with Micrococcus luteus ATCC 9341. Pastes that were not placed into root canals served as control. After pre-diffusion, incubation and optimization, the inhibition zones of bacterial growth were measured and analyzed by Mann-Whitney U test at 5% significance level. All pastes showed residual antibacterial activity. The control samples had larger halos (p<0.05). The mean residual antibacterial activity halos in G1, G2, G3 and G4 were 7.6; 10.4; 17.7 and 21.4 mm, respectively. The zones of bacterial growth of G4 were significantly larger than those of G1 and G2 (p<0.05). In conclusion, regardless of the vehicle and antiseptic, all Ca(OH)2-based pastes showed different degrees of measurable residual antibacterial activity. Furthermore, unlike CMCP, chlorhexidine increased significantly the antibacterial activity of Ca(OH)2.

PMID: 17639193 [PubMed - indexed for MEDLINE]

Comparative chemical study of MTA and Portland cements.

Braz Dent J. 2007;18(1):3-7

Authors: Oliveira MG, Xavier CB, Demarco FF, Pinheiro AL, Costa AT, Pozza DH

Portland cement has been analyzed and compared to mineral trioxide aggregate (MTA) because of their chemical similarity. The possibility of using this material as a less expensive alternative to MTA in dental practice should be considered. In view of this, the present study compared the components of a Portland cement (Votoran) to two commercial brands of MTA (Pro-Root and MTA-Angelus). Twelve specimens of each material were fabricated and examined by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) to obtain their percentage of chemical elements. The means of the chemical elements found in each material was compared by descriptive statistics. Bismuth was present only in MTA cements to provide radiopacity. In conclusion, the tested cements have similar components, which supports, as far as composition is concerned, the possible clinical use of Portland as an option to MTA.

PMID: 17639192 [PubMed - indexed for MEDLINE]

Apical seal comparison of low-temperature thermoplasticized gutta-percha technique and lateral condensation with two different master cones.

Med Oral Patol Oral Cir Bucal. 2007 Mar;12(2):E175-9

Authors: P&#xE9;rez Heredia M, Clavero González J, Ferrer Luque CM, González Rodríguez MP

AIM: To compare the apical sealing in mesio-buccal canals of extracted molars obturated with low-temperature thermoplasticized gutta-percha or cold lateral condensation techniques using a .06 or a .02 mm/mm tapered gutta-percha master cone. The secondary aim was to evaluate the depth of spreader penetration in root canals using a .06 or a .02 mm/mm tapered gutta-percha master cone. METHODOLOGY: Forty-four mesio-buccal curved canals (25-40 degree) were instrumented with .06 nickel-titanium rotary instruments and randomly distributed into two control groups (n=4) and three experimental groups (n=12) for obturation by the Ultrafil 3D system or by cold lateral condensation with .06 or .02 tapered master cone. Canal sealer AH-Plus was used. The depth of spreader penetration was recorded in millimetres. Roots were covered with two layers of nail polish, immersed in India ink for 7 days, transversally sectioned and examined with a stereomicroscope. Student s t test was used to determine whether there was a difference in spreader penetration between groups. Kruskal-Wallis test was used to determine whether there was a difference in leakage. RESULTS: There were no differences among the three groups (p=0.396), which showed a very similar mean microleakage (0.42, 0.75 and 0.42). The difference in spreader penetration between the groups filled by cold lateral condensation was significant (p=0.001) CONCLUSION: The Ultrafil 3D system and cold lateral condensation techniques with .06 or .02 tapered master cones were equally effective in the apical sealing of curved canals. The spreader penetrated deeper using a .02 mm/mm tapered gutta-percha master cone.

PMID: 17322810 [PubMed - indexed for MEDLINE]

Sealer penetration and marginal permeability after apicoectomy varying retrocavity preparation and retrofilling material.

Braz Dent J. 2006;17(4):323-7

Authors: Winik R, Araki AT, Negrão JA, Bello-Silva MS, Lage-Marques JL

Apicoectomy failure is generally related to inappropriate marginal sealing of the retrocavity, which allows percolation of microorganisms and their products from root canal system to periapex. This study evaluated tubular penetration of canal sealers and marginal permeability after retrocavity irradiation with Er;Cr:YSGG laser and retrofilling with MTA or cyanoacrylate. Twenty-two single-rooted teeth were decoronated and endodontically treated, their apical 3 mm were resected and the root ends were retroprepared with a low-speed bur. Twenty roots were randomly assigned to 4 groups (n=5): GI and GII--retrofilling with MTA and cyanoacrylate, respectively; GIII and GIV--retrocavity irradiation with Er;Cr:YSGG laser (2.78 microm, 4 W, 20 Hz, 70.8 J/cm(2)) and retrofilling with MTA and cyanoacrylate, respectively. The remaining 2 roots served as positive and negative controls. The analysis of rhodamine B dye infiltration (p=0.05) demonstrated that laser irradiation and MTA retrofilling presented significantly higher permeability rates (p<0.05). Retrofilling with cyanoacrylate showed significantly lower permeability, either when laser was used or not on retrocavity. SEM analysis depicted more cyanoacrylate penetration through dentinal tubules when compared to MTA, suggesting a more efficient marginal sealing. Based on these results, it may be concluded that cyanoacrylate provided a less permeable retrofilling regardless of the retropreparation method, suggesting a more favorable condition to the establishment of the periapical healing.

PMID: 17262147 [PubMed - indexed for MEDLINE]

Antimicrobial analysis of different root canal filling pastes used in pediatric dentistry by two experimental methods.

Braz Dent J. 2006;17(4):317-22

Authors: Amorim Lde F, Toledo OA, Estrela CR, Decurcio Dde A, Estrela C

The objective of this study was to compare, by two experimental methods, the antimicrobial efficacy of different root canal filling pastes used in pediatric dentistry. The tested materials were: Guedes-Pinto paste (GPP), zinc oxide-eugenol paste (OZEP), calcium hydroxide paste (CHP), chloramphenicol + tetracycline + zinc oxide and eugenol paste (CTZP) and Vitapex. Fiven microbial strains (S. aureus, E. faecalis, P. aeruginosa, B. subtilis and C. albicans) obtained from the American Type Culture Collection were inoculated in Brain Heart Infusion (BHI) and incubated at 37 degrees C for 24 h. For the direct exposure test (DET), 72 paper points were contaminated with the standard microbial suspensions and exposed to the root canal filling pastes for 1, 24, 48 and 72 h. The points were immersed in Letheen Broth (LB), followed by incubation at 37 degrees C for 48 h. An inoculum of 0.1 mL obtained from LB was then transferred to 7 mL of BHI, under identical incubations conditions and the microbial growth was evaluated. The pastes showed activity between 1 and 24 h, depending on the material. For the agar diffusion test (ADT), 30 Petri plates with 20 mL of BHI agar were inoculated with 0.1 mL of the microbial suspension, using sterile swabs that were spread on the medium. Three cavities were made in each agar plate (total = 90) and completely filled with one of the filling root canal pastes. The plates were pre-incubated for 1 h at room temperature and then incubated at 37 degrees C for 24 to 48 h. The inhibition zone around each well was recorded in mm. The complete antimicrobial effect in the direct exposure test was observed after 24 h on all microbial indicators. All root canal filling materials induced the formation of inhibition zones, except for Vitapex (range, 6.0-39.0 mm).

PMID: 17262146 [PubMed - indexed for MEDLINE]

In vitro cytotoxic and non-genotoxic effects of gutta-percha solvents on mouse lymphoma cells by single cell gel (comet) assay.

Braz Dent J. 2006;17(3):228-32

Authors: Ribeiro DA, Marques ME, Salvador DM

Chloroform and eucalyptol are widely used in clinical dentistry as gutta-percha solvents. However, these compounds may represent a hazard to human health, especially by causing injury to genetic apparatus and/or inducing cellular death. In this study, the genotoxic and cytotoxic potentials associated with exposure to chloroform and eucalyptol were assessed on mouse lymphoma cells in vitro by the single cell gel (comet) assay and trypan blue exclusion test, respectively. Both gutta-percha solvents proved to be cytotoxic at the same levels in concentrations of 2.5, 5 and 10 microL/mL (p<0.05). On the other hand, neither of the solvents induced DNA breakage. Taken together, these results suggest that although both tested compounds (chloroform and eucalyptol) are strong cytotoxicants, it seems that they are not likely to increase the level of DNA damage on mammalian cells.

PMID: 17262130 [PubMed - indexed for MEDLINE]

In vitro evaluation of the antimicrobial activity of endodontic sealers.

Braz Oral Res. 2006 Oct-Dec;20(4):303-6

Authors: Miyagak DC, de Carvalho EM, Robazza CR, Chavasco JK, Levorato GL

The purpose of this study is to evaluate the antimicrobial activity of the endodontic sealers: N-Rickert, Sealapex, AH Plus, Mineral Trioxide Aggregate (MTA) and portland cement. The Agar diffusion method was used in plates previously inoculated with the following microorganisms: C. albicans, S. aureus, E. faecalis, E. coli. The diameters of microbial inhibition zones were measured after 24 hours of incubation in kiln at 37 degrees C. According to the methodology used, it was possible to conclude that only the sealers AH Plus and N-Rickert presented antimicrobial activity against C. albicans, S. aureus, and E. coli; no antimicrobial activity in MTA, Sealapex and portland cement was observed. N-Rickert presented the largest inhibition zones varying from 8 to 18 mm, and the microorganism E. faecalis was resistant against all sealers tested.

PMID: 17242789 [PubMed - indexed for MEDLINE]

Methodologies for assessment of apical and coronal leakage of endodontic filling materials: a critical review.

J Oral Sci. 2006 Sep;48(3):93-8

Authors: Ver&#xED;ssimo DM, do Vale MS

Apical leakage continues to be a topic of great interest, because in spite of the advances in Endodontics, clinical failures still occur. Most failures are probably attributed to the proliferation of bacteria that remain viable after chemical-mechanical preparation and cause periapical tissue irritation. Coronal leakage has aroused researchers' interest over the last few years, since canals may be re-contaminated after loss of coronal sealing or fracture of the remaining tooth. In this review, the various methodologies used for assessing root canal sealing capacity are critically analyzed, as they are not standardized, which makes it difficult to compare the results obtained when different methodologies are used, even though the same substrate is being assessed.

PMID: 17023739 [PubMed - indexed for MEDLINE]

Apical leakage of Resilon obturation material.

J Contemp Dent Pract. 2006 Sep 1;7(4):45-52

Authors: Bodrumlu E, Tunga U

AIM: The aim of this study was to assess the apical sealing ability of Resilon obturation material. METHODS AND MATERIALS: Forty-two single rooted extracted human teeth were selected and randomly divided into three groups. They were obturated using lateral condensation with gutta-percha and AH 26/AH plus and Resilon; also, 12 root canals were used as control groups. The apical leakage was measured using the dye penetration methodology. RESULTS: The teeth filled with gutta-percha and AH 26 displayed the most apical leakage. The least apical leakage was shown with Resilon. DISCUSSION: The differences in leakage among the groups, gutta-percha with AH 26 (2.4 mm, SD:1.87), gutta-percha with AH plus (2.1 mm, SD: 1.69), and Resilon (1.7 mm, SD:1.32), were statistically significant (p< 0.001). CONCLUSION: Based on the data of this study, all groups produced a satisfactory seal. However, Resilon and Epiphany sealer showed the least apical leakage.

PMID: 16957790 [PubMed - indexed for MEDLINE]

Mineral trioxide aggregate.

J Am Dent Assoc. 2006 Sep;137(9):1214, 1216; author reply 1216

Authors: Needleman HL

PMID: 16946419 [PubMed - indexed for MEDLINE]

Effectiveness of rotary and hand files in gutta-percha and sealer removal using chloroform or chlorhexidine gel.

Braz Dent J. 2006;17(2):139-43

Authors: Bueno CE, Delboni MG, de Ara&#xFA;jo RA, Carrara HJ, Cunha RS

The purpose of this study was to assess in vitro the efficacy of nickel-titanium K3 rotary files and hand files for removal of gutta-percha and sealer from obturated root canals using either chloroform or chlorhexidine as solvents. Sixty extracted single-rooted bovine teeth with straight, large canals were prepared, obtured and randomly assigned to 3 groups (n=20). The teeth were stored at 37 degrees C for 1 month and then the gutta-percha and sealer were removed using different techniques, as follows. Group I: size 3 Gates-Glidden drills plus size 30 hand K-files and Hedström files and chloroform; Group II: K3 NiTi rotary files and chloroform; and Group III: K3 NiTi rotary files and 2% chlorhexidine gel. Radiographs were taken and scanned and the images were digitized. The total area of the canal and the area with remaining obturation material were measured in millimeters using a computed image analysis system (ImageLab). Data were analyzed statistically by one-way ANOVA and Tukey test at 5% significance level. The groups differed statistically (p<0.05) with respect to the average percentage of remaining gutta-percha and sealer, presenting the following sequence of effectiveness (from most to least effective): Group I (15.48%), Group II (28.42%) and Group III (35.96%). The findings of this study showed that, despite the technique used for removal of filling material, none of the retreated canals were completely free of gutta-percha and sealer remnants. The use of stainless steel hand files resulted in a lesser amount of filling debris than the use of nickel-titanium rotary instruments.

PMID: 16924342 [PubMed - indexed for MEDLINE]

Effect of eugenol-based endodontic cement on the adhesion of intraradicular posts.

Braz Dent J. 2006;17(2):130-3

Authors: Alfredo E, de Souza ES, Marchesan MA, Paulino SM, Gariba-Silva R, Sousa-Neto MD

The present study evaluated, in vitro, the influence of an eugenol-based endodontic sealer (EndoFill) on the adhesion of intra-radicular posts cemented with a resin-based cement (Enforce) ou a zinc phosphate cement. Twenty-four single-rooted maxillary canines were divided into 2 groups (n=12) and obturated with either gutta-percha points plus EndoFill or gutta-percha points alone (no cement). In each group, half of intracanal posts (n=6) were cemented with Enforce resin-based cement and half with zinc phosphate cement. Specimens were submitted to pull-out test in an Instron machine and tensile force was applied at a crosshead speed of 0.5 mm/min until post dislodgement. The maximum forces required for post removal was recorded (N) and means were submitted to statistical analysis by Kruskal-Wallis test (p<0.01). Posts cemented with zinc phosphate cement were significantly more retentive (353.4 N) than those cemented with Enforce (134.9 N) (p<0.01). Regarding the influence of the eugenol-based cement (EndoFill) on post retention, there was statistically significant difference (p<0.01) only between the groups cemented with Enforce, i.e., in the canals filled with EndoFill + guta-percha there was lower bond strength than in the canals filled with gutta-percha points alone (101.5 and 168.2 N, respectively). In conclusion, the zinc-phosphate-based cement showed greater post retention than the resin-based cement. The findings of this study suggest that the eugenol-containing sealer interfered with the adhesive properties of the resin-based cement.

PMID: 16924340 [PubMed - indexed for MEDLINE]

Improvement of eczematous symptoms after removal of amalgam-like metal in alveolar bone.

Bull Tokyo Dent Coll. 2006 Feb;47(1):13-7

Authors: Matsuzaka K, Mabuchi R, Nagasaka H, Yoshinari M, Inoue T

This case report describes a 55-year-old woman with an amalgam-like metal remaining in alveolar bone after root-end sealing in 1964, and who then developed eczematous facial symptoms from 2000 onwards. Removal of the amalgam-like metal material improved the symptoms.

PMID: 16924154 [PubMed - indexed for MEDLINE]

Dentin penetrability evaluation of three different dyes in root-end cavities filled with mineral trioxide aggregate (MTA).

Braz Oral Res. 2006 Apr-Jun;20(2):132-6

Authors: Vogt BF, Xavier CB, Demarco FF, Padilha MS

The purpose of this study was to evaluate the penetration of three dyes in MTA root-end fillings. In 30 single-rooted teeth, cavities for retrofilling were prepared with an ultrasound appliance and filled with MTA. The specimens were randomly assigned to three groups (n = 10) and immersed in the following solutions: 2% methylene blue (MET), 50% silver nitrate (NIT) and 0.2% rhodamine B (ROD). Two transversal slices (1 mm) of the retrofilling region were obtained and evaluated using the Image Tool 3.0 software to obtain a quantitative evaluation (in mm2) of the dye penetration around the retrofillings. Data were submitted to statistical analysis using Students t-test. The lowest degree of dye penetration was observed for the NIT group, in both slices (p < 0.05). Dye penetration was significantly larger in the ROD group when compared to the NIT group, in both slices (p < 0.05), and to the MET group, only in slice 1 (p < 0.05). Within the limitations of this study, it was concluded that the choice of dye could influence the penetration evaluation in root-end filling studies, and that the NIT had the lowest penetration capacity in the apical dentine.

PMID: 16878206 [PubMed - indexed for MEDLINE]

Evaluation of the antimicrobial activity of each component in Grossman's sealer.

Braz Oral Res. 2006 Apr-Jun;20(2):127-31

Authors: Savioli RN, Pecora JD, Mian H, Ito IY

The antimicrobial activity of Grossman's sealer and its components was evaluated on 13 different strains using the double layer well-diffusion method. Results revealed that Grossman's sealer presented antimicrobial activity against all the tested strains. Among the components of the cement, sodium tetraborate presented the greatest antimicrobial activity, both in type and diameter of the halo and ring of inhibition. Sealer powder, rosin, and eugenol presented similar activity, with no effect on P. aeruginosa and C. albicans. Among these, only eugenol had an effect on E. coli. Zinc oxide was only active against S. sobrinus and E. coli. Barium sulfate and bismuth subcarbonate did not show any antimicrobial effect.

PMID: 16878205 [PubMed - indexed for MEDLINE]

Treatment of pulp floor and stripping perforation by mineral trioxide aggregate.

J Formos Med Assoc. 2006 Jun;105(6):522-6

Authors: Tsai YL, Lan WH, Jeng JH

Mineral trioxide aggregate (MTA) has been widely used to repair various kinds of tooth perforations, but its use for obturation of the entire root canal has not been reported. We report two cases of tooth perforation successfully repaired with MTA. The first patient was a 78-year-old male with calcified canal and pulp floor perforation in the left maxillary first premolar. After bypass of the calcified palatal canal, both buccal and palatal canals were filled with gutta percha, and the pulp floor perforation was repaired with MTA. Clinical success with no evident radicular lesion was found at the 18-month follow-up. The second patient was a 51-year-old female with a stripping perforation in a C-shaped root canal of the right mandibular second molar detected after removal of a post. Following root canal debridement and calcium hydroxide therapy to control inflammation at the stripping perforation site, apical and furcation bone healing were observed by radiographic examination. The stripping perforation was repaired by obturation of the entire C-shaped root canal with MTA. Observation at the 9-month follow-up revealed bone healing without any clinical symptoms and signs. These cases suggest that MTA is an alternative root canal obturation material for treatment of stripping perforation in a C-shaped root canal and for repair of pulp floor perforation.

PMID: 16801043 [PubMed - indexed for MEDLINE]

Endodontic management of taurodontic teeth.

Indian J Dent Res. 2005 Oct-Dec;16(4):177-81

Authors: Prakash R, Vishnu C, Suma B, Velmurugan N, Kandaswamy D

Taurodontism is a morpho-anatomical change in the shape of the tooth in which the body of the tooth is enlarged and the roots are reduced in size. Although taurodontism is a dental rarity, this unusual radicular form should merit circumspect considerations in planning and treatment. Endodontic management in taurodont teeth has been described as complex and difficult. The present paper describes the successful completion of endodontic treatment in three taurodontic teeth with appropriate use of instruments and techniques and also emphasizes the need for post endodontic rehabilitation.

PMID: 16761713 [PubMed - indexed for MEDLINE]

Analysis of the sealing ability of different obturation techniques in oval-shaped canals: a study using a bacterial leakage model.

Braz Oral Res. 2006 Jan-Mar;20(1):64-9

Authors: De Deus G, Murad CF, Reis CM, Gurgel-Filho E, Coutinho Filho T

The aim of this study was to evaluate the sealing ability of 3 obturation techniques in oval canals using a bacterial leakage model. Seventy mandibular incisors with oval canals were selected after buccolingual and mesiodistal radiographs, and divided into three groups. After instrumentation, the canals were obturated respectively by lateral condensation (G1), warm vertical condensation (G2) and Thermafil (G3). Five root canals were not obturated and served as positive controls; five teeth with intact crowns served as negative controls. All teeth were mounted on a 2 chamber apparatus and then exposed to human saliva. The number of days required for the entire contamination of the root canals was recorded, observing the turbidity of the BHI broth, for a period of 100 days. 84.21% of the samples from the lateral condensation group (G1); 84.21% of the samples from the warm vertical condensation group (G2); and 89.47% of the samples from the Thermafil System group (G3) showed no contamination at the end of the study. No statistical significant difference was found among the three techniques. The quality of the apical seal in the three techniques tested was similar.

PMID: 16729177 [PubMed - indexed for MEDLINE]

Anatomical redesign for the treatment of dens invaginatus type III with open apexes: a literature review and case presentation.

J Am Dent Assoc. 2006 Feb;137(2):180-5

Authors: Silberman A, Cohenca N, Simon JH

BACKGROUND: Dens invaginatus is a rare dental anomaly that may give rise to many complex anatomical forms. The complexity of the internal anatomy may create challenges for the complete removal of the diseased pulpal tissue and the subsequent sealing of the canal system. CASE DESCRIPTION: The authors discuss the modification of the internal anatomy under the operating microscope, allowing the clinician better access to treat predictably the canal system with conventional or alternative techniques. CONCLUSION AND CLINICAL IMPLICATIONS: Considering the anatomical variations and the challenges that a dens invaginatus may present, a practitioner may consider a modification of the internal anatomy of the canal system to gain better access for proper instrumentation, disinfection and sealing of the root canal system using conventional or contemporary techniques.

PMID: 16521383 [PubMed - indexed for MEDLINE]

Outcome of endodontic treatment of teeth filled using lateral condensation versus vertical compaction (Schilder's technique).

J Contemp Dent Pract. 2006 Feb 15;7(1):17-24

Authors: Aqrabawi JA

The purpose of this prospective clinical and radiographic investigation was to assess the treatment results following endodontic therapy of teeth filled with lateral condensation versus teeth filled with vertical compaction of warm gutta-percha. A total of 290 patients were treated using the standardized step-back technique for canal preparation, which were filled with either lateral condensation or vertical compaction in one single session. Five years later, the treatment results were assessed clinically and radiographically and related to the type of the obturation technique using Chi-square analysis. Of the 340 teeth that were reexamined, 160 teeth were filled with lateral condensation, and 180 teeth were filled with vertical condensation. The results showed a significantly higher success rate for the vertical compaction versus the lateral condensation technique of teeth presented with preoperative periapical lesions P<0.04. Regardless of the preoperative periapical status of the teeth, no statistically significant difference was found between the two techniques. The overall success rate of both filling techniques was 80.3%.

PMID: 16491144 [PubMed - indexed for MEDLINE]

A radiographic study of the relationship between technical quality of coronoradicular posts and periapical status in a Jordanian population.

J Oral Sci. 2005 Sep;47(3):123-8

Authors: Jamani KD, Aqrabawi J, Fayyad MA

A radiographic study was conducted to investigate the relationship between the technical quality of coronoradicular posts and periapical status. A total of 400 periapical radiographs, including 560 posts, of patients attending the Dental Department at Jordan University Hospital were scanned and studied. It was found that maxillary teeth were more frequently restored with posts (65.36%) than mandibular teeth (34.64%). Tapered posts accounted for 73.93% of the posts used. The ratio of the mean post length to crown length was 0.8, and that to root length was 0.45. The mean length of the remaining gutta percha apical to the end of the post was 6.22 mm. In addition, 25% of the posts deviated from the line of the root canal. Periapical radiolucency was evident in 53.93% of the assessed teeth. It is concluded that inadequate root canal treatment and coronoradicular posts are associated with increased prevalence of periapical radiolucency, and that general dental practitioners should be better trained in performing endodontic treatment and restoring endodontically treated teeth.

PMID: 16313089 [PubMed - indexed for MEDLINE]

Brazilian gutta-percha points. Part I: chemical composition and X-ray diffraction analysis.

Braz Oral Res. 2005 Jul-Sep;19(3):193-7

Authors: Maniglia-Ferreira C, Silva JB, Paula RC, Feitosa JP, Cortez DG, Zaia AA, Souza-Filho FJ

Eight nonstandardized gutta-percha points commercially available in Brazil (Konne, Tanari, Endopoint, Odous, Dentsply 0.04, Dentsply 0.06, Dentsply TP and Dentsply FM) were analysed chemically and by X-ray diffraction, and their chemical compositions were compared. The organic fraction (gutta-percha polymer and wax/resin) of the gutta-percha points was separated from the inorganic fraction (ZnO and BaSO4) by dissolving them in chloroform. The gutta-percha polymer was precipitated with acetone. The inorganic fraction was analysed by elemental microanalysis. Energy-dispersive X-ray microanalysis (EDX) and X-ray diffraction were employed to identify the chemical elements and compounds (barium sulfate and zinc oxide). The barium sulfate content was calculated based on the percentage of sulfur found in the elemental microanalysis. All analyses were repeated three times. The means and standard deviations of the percentage by weight of gutta-percha in the points were: Konne (17.6 +/- 0.30), Tanari (15.2 +/- 0.30), Endopoint (16.7 +/- 0.23), Odous (18.8 +/- 0.20), Dentsply 0.04 (15.7 +/- 0.17), Dentsply 0.06 (16.6 +/- 0.17), Dentsply TP (21.6 +/- 0.15) and Dentsply FM (16.3 +/- 0.23). The means and standard deviations of the zinc oxide content were: Konne (79.9 +/- 0.10), Tanari (81.9 +/- 0.07), Endopoint (81.3 +/- 0.40), Odous (79.7 +/- 0.26), Dentsply 0.04 (77.9 +/- 0.03), Dentsply 0.06 (78.2 +/- 0.07), Dentsply TP (69.8 +/- 0.19) and Dentsply FM (72.6 +/- 0.70). The method utilized was appropriate to quantify gutta-percha, wax/resin, zinc oxide and barium sulfate. Cone brands without barium sulfate were found. An unusual high wax/resin percentage was detected in Dentsply FM (p = 0.0003). Dentsply TP showed the highest gutta-percha percentage.

PMID: 16308607 [PubMed - indexed for MEDLINE]

Effect of different dye solutions on the evaluation of the sealing ability of Mineral Trioxide Aggregate.

Braz Oral Res. 2005 Apr-Jun;19(2):119-22

Authors: Tanomaru Filho M, Figueiredo FA, Tanomaru JM

Alkaline materials have shown incompatibility with methylene blue dye in leakage experiments. The goal of the present study was to analyze the effect of different dyes on the evaluation of the apical sealing ability of Mineral Trioxide Aggregate root-end fillings. Fifty-six extracted human canines were submitted to root canal instrumentation and obturation. After apical resection, retrograde cavities were prepared and teeth were randomly divided into four experimental (n = 13) and two control groups (n = 2). The following root-end filling materials were used: groups 1 and 2--Pro Root MTA (Dentsply), groups 3 and 4--zinc oxide-eugenol cement (ZOE). Teeth in groups 1 and 3 were immersed in 2% methylene blue solution, while teeth in groups 2 and 4 were immersed in 0.2% rhodamine B in a reduced pressure environment for 48 hours. Teeth were then longitudinally sectioned and leakage was evaluated. Results were submitted to statistical analysis (ANOVA and Tukey's test). Group 1 presented the least leakage (p < 0.05). It was concluded that the evaluation of the sealing ability of MTA is influenced by the dye used, since this material presented better sealing ability when evaluated with Methylene Blue, but was similar to ZOE when evaluated with rhodamine B.

PMID: 16292444 [PubMed - indexed for MEDLINE]

Microbial leakage of Cavit, IRM, and Temp Bond in post-prepared root canals using two methods of gutta-percha removal: an in vitro study.

J Contemp Dent Pract. 2005 Aug 15;6(3):53-61

Authors: Balto H, Al-Nazhan S, Al-Mansour K, Al-Otaibi M, Siddiqu Y

The aim of this study was to evaluate the integrity of the coronal seal of Temp-Bond and compare it to Cavit and IRM after post space preparation using S. faecalis as a microbial tracer. In addition, the affect of two methods of gutta percha removal on the apical seal of root canal fillings was also evaluated. Forty extracted human single rooted teeth were prepared chemomechanically and obturated with gutta percha and AH26 sealer cement using the lateral cold condensation technique to a standardized working length of 15 mm. About 10 mm of the coronal gutta-percha was removed with either Peeso-reamer or a hot plugger. The roots were divided into three experimental groups of 10 roots and a control group. Each experimental group was subdivided equally into two groups of 15 each according to the method of post space preparation. Cavit, IRM, and Temp-Bond were used to seal the access opening. Each root was fixed in a cuvette containing Tryptic Soya Broth which, covered 2 mm of the root apex. Bacterial suspension was introduced through pipette. Fresh bacterial suspension was added every week, and the system was monitored daily for the growth of microorganisms for a period of one month. The results showed there was no significant difference in terms of coronal leakage between the three coronal materials used (P=0.478), but the methods of gutta-percha removal did have an impact on the apical leakage (P=0.047). The mean value showed the Peeso-reamer provided less leakage compared to using a hot plugger during the 30-day experimental time period. It was concluded the temporary type of coronal seal of endodontically treated teeth will not prevent coronal leakage if left for a long period of time. In addition, permanent cementation of the post with the coronal restoration should be carried out as soon as possible to prevent recontamination of the root canal.

PMID: 16127472 [PubMed - indexed for MEDLINE]

Influence of apical patency and filling material on healing process of dogs' teeth with vital pulp after root canal therapy.

Braz Dent J. 2005;16(1):9-16

Authors: Holland R, Sant'Anna J&#xFA;nior A, Souza V, Dezan Junior E, Otoboni Filho JA, Bernabé PF, Nery MJ, Murata SS

The purpose of this study was to investigate the periapical healing process of dogs' teeth with or without apical patency and after root canal filling with two types of sealers. Forty roots of premolars and incisors were utilized. The root canals were over-instrumented and dressed with a corticosteroid-antibiotic solution for 7 days to obtain ingrowth of periapical connective tissue into the canals. After this period, the tissue was removed in half of the specimens (groups with patency) and preserved in the other half (groups without patency). Canals were filled by lateral condensation technique with gutta-percha points and either a calcium hydroxide-based sealer (Sealer Plus) or a Grossman's cement (Fill Canal). The animals were killed by anesthetic overdose 60 days after the endodontic treatment and anatomic pieces were obtained and prepared for histologic examination. Data were evaluated in a blind analysis on the basis of several histomorphologic parameters. The groups without patency had better results (p=0.01) than those in which the ingrown connective tissue was removed. Comparing the sealers, Sealer Plus had significantly better results (p=0.01) than Fill Canal. In conclusion, both the apical patency (presence or absence) and the type of root canal filling material influenced the periapical healing process in dogs' teeth with vital pulp after root canal treatment. The use of a calcium hydroxide-based sealer in teeth without apical patency yielded the best results among the experimental conditions proposed.

PMID: 16113927 [PubMed - indexed for MEDLINE]

Endodontics.

J Am Dent Assoc. 2005 May;136(5):581-2; author reply 582

Authors: Piacine MJ

PMID: 15966645 [PubMed - indexed for MEDLINE]

Histomorphological response of dogs' dental pulp capped with white mineral trioxide aggregate.

Braz Dent J. 2004;15(2):104-8

Authors: Faraco Junior IM, Holland R

This study was conducted to observe the response of dogs' dental pulp to white mineral trioxide aggregate (MTA) when used as pulp capping material. The pulp of 15 dogs' teeth was experimentally exposed and capped with white MTA. The animals were sacrificed two months later and the specimens were prepared for histomorphological study. The pulp capped with white MTA showed a healing process with complete dentin bridge formation in all samples. In some cases, there was not a tubular dentin shape, but only a structure with an interesting morphological aspect sealing the exposure site. Only 2 specimens exhibited pulp inflammation. In conclusion, the data obtained in this study showed that white MTA has the necessary properties of a pulp capping material.

PMID: 15776191 [PubMed - indexed for MEDLINE]

Success of an alternative for interim management of irreversible pulpitis.

J Am Dent Assoc. 2004 Dec;135(12):1707-12

Authors: McDougal RA, Delano EO, Caplan D, Sigurdsson A, Trope M

BACKGROUND: Extraction and endodontic therapy are treatment options for irreversible pulpitis. Extraction often is chosen for financial reasons. The authors conducted a study to investigate an alternative interim therapy. METHODS: The authors recruited patients (N = 73) with irreversible pulpitis and whose teeth were restorable but who opted for extraction owing to financial reasons. After undergoing pulpotomy, the teeth were restored by random assignment with one of two intermediate restorative materials: Caulk IRM (Dentsply Caulk, Milford, Del.) (Group I, n = 38) or an IRM base with glass ionomer core (Fuji IX GP, GC America, Alsip, Ill.) (Group II, n = 35). The authors monitored the teeth over six and 12 months for pain, integrity of restoration and radiographic periapical status by densitometric analysis. RESULTS: By six months, 10 percent of subjects remaining in the study (Group I, n = 27; Group II, n = 25) reported pain; by 12 months, 22 percent (Group I, n = 22; Group II, n = 18) reported pain. A two-tailed Fisher exact test showed no significant difference (P > or = .05) between groups at either time interval. No apical radiographic change was noted in 49 percent of teeth at six months (Group I, n = 18; Group II, n = 19) and 42 percent at 12 months (Group I, n = 16; Group II, n = 15). Chi2 analysis demonstrated no significant differences (P > or = .05) between groups. Seven of 22 restorations in Group I and four of 18 in Group II required repair at 12 months with no statistical difference (chi2 analysis, P > or = .05). CONCLUSIONS: The interim treatment of eugenol pulpotomy using either restorative material reliably prevented pain for six months. For longer periods, both restorations may require repair. CLINICAL IMPLICATIONS: This option should preserve the integrity of the arch and extend the use of the tooth while the patient finds the means to finance complete endodontic treatment.

PMID: 15646604 [PubMed - indexed for MEDLINE]

The pH changes of four different root canal sealers after mixing at various time intervals in vitro.

J Contemp Dent Pract. 2004 Nov 15;5(4):71-8

Authors: Evcil MS, Colak M

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.

PMID: 15558092 [PubMed - indexed for MEDLINE]

Fracture resistance of roots endodontically treated with a new resin filling material.

J Am Dent Assoc. 2004 May;135(5):646-52

Authors: Teixeira FB, Teixeira EC, Thompson JY, Trope M

BACKGROUND: The authors evaluated the fracture resistance of endodontically treated teeth filled with either gutta-percha or a new resin-based obturation material. METHODS: The authors prepared and randomly divided 80 single-canal extracted teeth into five groups: lateral and vertical condensation with gutta-percha, lateral and vertical condensation with the new resin-based obturation material, and a control group with no filling material. The specimens were stored in 100 percent humidity for two weeks, mounted in polyester resin and loaded to failure. RESULTS: The authors found statistically significant differences among the experimental groups (P < .05). The groups with the new material displayed higher mean fracture loads and the gutta-percha groups lower mean fracture load values than the control unfilled group. However, the differences were not significant. The groups with the new material displayed significantly higher mean fracture loads than gutta-percha groups independent of the filling technique used. CONCLUSIONS: Filling the canals with the new resin-based obturation material increased the in vitro resistance to fracture of endodontically treated single-canal extracted teeth when compared with standard gutta-percha techniques. CLINICAL IMPLICATIONS; If other properties of the new resin-based obturation material compare favorably with those of gutta-percha for filling the root canal, it should be considered as a replacement for gutta-percha, as the results of this study indicate that it could provide enhanced resistance to tooth fracture.

PMID: 15202759 [PubMed - indexed for MEDLINE]

The effects of water and acetone-based dentin adhesives on apical microleakage.

J Contemp Dent Pract. 2004 May 15;5(2):93-101

Authors: Karadag LS, Bala O, T&#xFC;rköz E, Mihçioğlu T

In this study, the aim was to assess the in vitro apical microleakage of a resin-based sealer used with two different adhesives. Thirty nine freshly extracted maxillary incisors were used. The teeth were decoronated at the cemento-enamel junction with a water-cooled fissure bur. Chemo-mechanical debridement of the root canals was accomplished with the step-back technique. The smear layer was removed by 19% ethylenediamine tetra acetic acid (EDTA). The roots were then divided into three experimental groups of thirteen teeth in each. Specimens in group 1 were filled with gutta-percha, AH Plus sealer, and water-based adhesive system (Syntac Single Component). Group 2 specimens were filled with gutta-percha, AH Plus sealer, and acetone-based dentin adhesive (Prime & Bond NT ). Specimens of group 3 were filled with only gutta-percha and AH Plus sealer (no adhesive was applied). The teeth were immersed into 2% methylene blue solution. Apical sealing qualities were assessed by measuring the linear dye penetration with a stereomicroscope. Dentin tubule penetration was observed under scanning electron microscopy (SEM). Results showed no statistically significant difference between the materials used, however, the leakage in group 2 was less than group 1 and 3.

PMID: 15150637 [PubMed - indexed for MEDLINE]

Root-end filling materials alter fibroblast differentiation.

J Dent Res. 2004 May;83(5):408-13

Authors: Bonson S, Jeansonne BG, Lallier TE

Root-end filling materials are commonly used following endodontic surgical procedures; however, their effect on adjacent soft tissues is poorly understood. We predict that, due to the differences in their chemical composition, these materials will have profoundly different effects on the survival and differentiation of fibroblasts. Many of the root-end filling materials examined were initially cytotoxic to both PDL and gingival fibroblasts in co-culture experiments; however, this was reduced after the materials were washed in either mineral trioxide aggregate (MTA) or hybrid ionomere composite resin (HICR) for 2 wks. Additionally, PDL fibroblasts displayed enhanced proliferation on MTA and survival on amalgam when compared with gingival fibroblasts. MTA preferentially induced alkaline phosphatase expression and activity in both PDL and gingival fibroblasts. In contrast, HICR inhibited alkaline phosphatase expression and activity. In addition, MTA and HICR repressed pleiotrophin in PDL fibroblasts, while HICR repressed periostin in both fibroblasts. Thus, root-end filling materials differentially affect periodontal fibroblast differentiation. Abbreviations: mineral trioxide aggregate (MTA), zinc-oxide eugenol cement (ZOEC), hybrid ionomer composite resin (HICR), reverse-transcriptase polymerase chain-reaction (RT-PCR).

PMID: 15111634 [PubMed - indexed for MEDLINE]

Removing gutta-percha for dowel space preparation.

J Am Dent Assoc. 2004 Mar;135(3):330

Authors: Kaplowitz GJ

PMID: 15058621 [PubMed - indexed for MEDLINE]

[The comparison of performance between calcium hydroxide and metapex root canal filling materials in apexification of young permanent teeth]

Shanghai Kou Qiang Yi Xue. 2002 Dec;11(4):382-4

Authors: Wang S

PMID: 14983390 [PubMed]

Influence of passive ultrasonic activation on the penetration depth of different sealers.

J Contemp Dent Pract. 2004 Feb 15;5(1):115-25

Authors: Karadag LS, Tinaz AC, Mih&#xE7;ioğlu T

Correct use of instruments and irrigating solutions are major factors during chemo-mechanical preparation of root canals. Ultrasonically activated files and solutions are used for debridement of canals. In this study 42 single rooted anterior human teeth were used. The roots were divided into two groups. One group received an application of 17% ethylenediamine tetra acetic acid (EDTA) of 1 ml for 1 min using an ultrasonically energized file. The other group received an application of 17% EDTA of 1 ml for 0.5 min using an ultrasonically energized file. The groups were divided again into two subgroups. The roots were filled with a resin based sealer, AH26 and a glass ionomer sealer--Endion with lateral condensation technique. The roots were separated into two halves. The specimens were viewed through a scanning electron microscope (SEM). Statistical differences between the groups and regions were analyzed with Variance and Duncan tests. Under the conditions of this study, it can be said that ultrasonically activated irrigation did not reduce the smear layer effectively at 1 min and 0.5 min time intervals. According to this result, no difference was observed between the penetration of sealers.

PMID: 14973565 [PubMed - indexed for MEDLINE]

[Analysis of short-term pain occurrence applying different materials for root canal therapy]

Shanghai Kou Qiang Yi Xue. 2003 Aug;12(4):260-2

Authors: Wang RF, Shao YS, Jiang JF, Song Y

OBJECTIVE: The aim of this study is to compare the occurrence of pain applying different materials of root canal therapy in vital teeth. METHODS: 288 vital teeth were divided into 4 groups, Cortisomol sealer+gutta-percha and Vitapex+gutta-percha were used respectively in 2 groups of one time method; while Cortisomol sealer+gutta-percha and Vitapex+gutta-percha were used after 24-48 hours drainage in the other 2 groups. The occurrence of pain after 1 week was recorded. RESULTS: In all treated teeth,the occurrence rate of self-healing pain after root canal therapy was 22.6%, the occurrence rate of non-self-healing was 2.08%; in the groups of one time method,the occurrence rate of pain using Cortisomol was lower than the group using Vitapex with significant difference(P<0.01); while in the groups of root canal filling after drainage,the occurrence of self-healing pain in the group using Cortisomol was lower than the group of using Vitapex without significant difference(P>0.05);the pain occurred within 72 hours in most of the teeth. CONCLUSION: Root canal treatment applying Cortisomol sealer+gutta-percha can decrease the rate of pain occurrence after root canal filling.

PMID: 14966636 [PubMed - indexed for MEDLINE]

[Clinical evaluation of zinc oxide eugenol and Vitapex as root canal filling materials in primary teeth]

Shanghai Kou Qiang Yi Xue. 2003 Oct;12(5):377-9

Authors: Zhang XF, Xu XB

PMID: 14966617 [PubMed - indexed for MEDLINE]

[Analysis of the effect on the stress of root canal wall by vertical and lateral condensation procedures]

Shanghai Kou Qiang Yi Xue. 2003 Oct;12(5):359-61

Authors: Hong J, Xia WW, Xiong HG

OBJECTIVE: To analyse the stress variations of root canal wall that resulted from vertical and lateral condensation. METHODS: On the basis of the finite-element model of the mandibular first molar that modified by step-back technique, mesial-buccal root canal was chosen as tested root canal and simulated the procedure of vertical and lateral condensation. The maximal stress of root canal wall and its position were calculated by special software upon different loading condition. RESULTS: Stress of root canal wall caused by vertical condensation was higher than that by lateral condensation on the same loading condition. Maximal stress of vertical condensation was located on loading section and one of lateral condensation was located on coronal and middle 1/3 of root. The lower the position that was loaded, the higher the stress of wall of root canal. CONCLUSION: Lateral condensation will not bring on vertical root fracture directly,but over-force and improper operation are both dangerous that gives rise to vertical root fracture with whichever method.

PMID: 14966612 [PubMed - indexed for MEDLINE]

[The clinical evaluation of tinidazole-iodoform root canal paste on treatment of chronic periapical periodontitis associated with ectopic sinus]

Shanghai Kou Qiang Yi Xue. 2003 Feb;12(1):73-4

Authors: Ji PH, Jiang ZM, Xu QL

PMID: 14661472 [PubMed - indexed for MEDLINE]

[The effect of pit and fissure sealants in teeth filling with silver amalgam]

Shanghai Kou Qiang Yi Xue. 2003 Jun;12(3):237-8

Authors: Yu YM, Liu XH, Li DL

PMID: 14661344 [PubMed - indexed for MEDLINE]

Analysis of the film thickness of a root canal sealer following three obturation techniques.

Pesqui Odontol Bras. 2003 Apr-Jun;17(2):119-25

Authors: de Deus GA, Martins F, Lima AC, Gurgel-Filho ED, Maniglia CF, Coutinho-Filho T

The aim of this study was to obtain a quantitative analysis of the film thickness of a root canal sealer formed after filling by three different techniques. Thirty human maxillary incisors were selected and access cavities were prepared using high-speed diamond stones and water spray. A size #15 K-Flexofile was introduced in the canal of each specimen until it was seen just at the apical foramen. The working length was determined to be 1 mm short of that position and the canals were prepared to an apical size of #45 K-Flexofile. Copious irrigation with 5.25% NaOCl (sodium hypochlorite) was used during and after instrumentation. The samples were divided into three groups and obturated as follows: G1 - lateral condensation, G2 - lateral condensation with an accessory cone, and G3 - continuous wave of condensation. The samples were evaluated in the cervical, middle and apical thirds. The film thickness of the root canal sealer was measured through a microscopic evaluation. Statistical analysis was obtained using the Wilcox test. Statistical analysis showed significant differences between G3 and G1, G3 and G2 (p < 0.05). In general, the lowest film thickness was observed in the continuous wave of condensation (G3). Lateral condensation with an accessory cone (G2) and lateral condensation (G1) demonstrated poorer results in this study, showing a higher film thickness. The small film thickness of the sealer obtained by the continuous wave of condensation technique may increase the clinical performance of this technique.

PMID: 14569352 [PubMed - indexed for MEDLINE]

Cytotoxic effects of cyanoacrylates used as retrograde filling materials: an in vitro analysis.

Pesqui Odontol Bras. 2003 Apr-Jun;17(2):113-8

Authors: de Azevedo CL, Marques MM, Bombana AC

Cyanoacrylate has been used in medicine and dentistry for many years. It has been used as a postextraction dressing and retrograde filling material in endodontic surgery. The aim of this study was to evaluate the cytotoxic effects of Histoacryl and other two homologue ethyl cyanoacrylates, Super Bonder and Ultrabond, on cultured fibroblasts, using the Trypan blue dye exclusion assay. The cyanoacrylates were applied to round glass coverslips, which were placed in contact with NIH 3T3 cells. After 0, 6, 12 and 24 h (short-term assay; viability) and 1, 3, 5 and 7 days (long-term assay; survival), the cells were examined under phase light microscopy and counted. The data were compared by the Kruskal-Wallis test. In the short-term experiments, only the cultures of the Ultrabond group (GIV) presented significant smaller percentages of cell viability than the cultures of the other groups (GI: control; GII: Super Bonder; GIII: Histoacryl). Although the cultures of the Super Bonder group (GII) presented smaller percentages of cell viability than cultures of the other groups (GI, GIII, GIV) at the long-term assay, this group was the only experimental group presenting a continuous and progressive cell growth. Our results have shown an in vitro biocompatibility of Histoacryl and ethyl cyanoacrylate homologues. These cyanoacrylates could therefore be of importance for endodontic purposes.

PMID: 14569351 [PubMed - indexed for MEDLINE]

Coronal microleakage assessed by polymicrobial markers.

J Contemp Dent Pract. 2003 Aug 15;4(3):1-10

Authors: Britto LR, Grimaudo NJ, Vertucci FJ

Studies have shown significant bacterial leakage following exposure of sealed root canals to artificial and natural saliva. The objective of this study was to determine contamination via bacterial migration in artificial saliva in endodontically treated teeth using different obturation techniques and sealers. A total of 144 extracted, human mandibular anterior teeth were cleaned and shaped to a #40 master apical file using hand and rotary instrumentation. One hundred and twenty teeth were divided into two experimental groups. The teeth in Group 1 were obturated with gutta-percha using lateral compaction and five different sealers, and the teeth in Group 2 were obturated with gutta-percha using thermomechanical compaction and five different sealers. The remaining 24 teeth were prepared as positive and negative controls. All specimens, except the negative controls, were inoculated every five days with Anaerobic streptococci (NCTC 9891) related to Peptostreptococcus micros and Prevotella intermedia (ATCC 25611). The contamination onset time was continuously recorded and turbid broths cultured for bacteria identification. The controls behaved as expected. Regardless of the combination between obturation techniques and different sealers, all broths became turbid during this experiment. The correlation between the obturation techniques and the sealers revealed statistical significance using ANOVA (p<0.0001), followed by the Duncan Multiple Range Test, which determined the ranking between these interactions. The combination of MicroSeal obturation technique with Ketac-Endo sealer allowed a slower rate of coronal-apical bacterial migration.

PMID: 12937592 [PubMed - indexed for MEDLINE]

In vitro evaluation of different chemical agents for the decontamination of gutta-percha cones.

Pesqui Odontol Bras. 2003 Jan-Mar;17(1):75-7

Authors: de Souza RE, de Souza EA, Sousa-Neto MD, Pietro RC

This study evaluated the effectiveness of three disinfectants used in Dentistry for decontamination of gutta-percha cones. Sixty gutta-percha cones were contaminated with standardized pure cultures of five species of microorganisms (Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, Candida albicans ATCC CBS-ICB/USP 562, Bacillus subtilis spores ATCC 6633 and Streptococcus mutans ATCC 25175). The cones were treated with 10% polyvinylpyrrolidone-iodine aqueous solution (PVP-I; Groups 1 and 2), 5.25% aqueous sodium hypochlorite (Groups 3 and 4) and paraformaldehyde tablets (Group 5). All chemical agents were efficient for the cold sterilization of gutta-percha cones in short time periods.

PMID: 12908064 [PubMed - indexed for MEDLINE]

Apical and periapical repair of dogs' teeth with periapical lesions after endodontic treatment with different root canal sealers.

Pesqui Odontol Bras. 2003 Jan-Mar;17(1):69-74

Authors: Leonardo MR, Salgado AA, da Silva LA, Tanomaru Filho M

The aim of this study was to evaluate the apical and periapical repair after root canal treatment of dogs' teeth with pulp necrosis and chronic periapical lesion using different root canal sealers. After periapical lesion induction, forty-four root canals of 3 dogs were submitted to biomechanical preparation using 5.25% sodium hypochlorite as an irrigating solution. A calcium hydroxide dressing (Calen PMCC) was applied for 15 days and the root canals were filled using the lateral condensation technique with gutta-percha points and Sealapex, AH Plus or Sealer Plus for sealing. After 180 days, the animals were sacrificed by anesthetic overdose and the obtained histological sections were stained with hematoxylin-eosin for optical microscopic analysis of the apical and periapical repair. The groups filled with Sealapex and AH Plus had better histological repair (p < 0.05) than the group filled with Sealer Plus, that had unsatisfactory results.

PMID: 12908063 [PubMed - indexed for MEDLINE]

Tissue reactions after intraosseous implantation of three retrofilling materials.

Bull Tokyo Dent Coll. 2003 Feb;44(1):1-7

Authors: Morinaga K, Nakagawa K, Carr GB

Bone tissue reactions to EBA, IRM, and cyanoacrylate cement (Base Liner) were studied in the rat mandible using an intraosseous implant method. Osseous cavities (1.4 mm in diameter) were surgically created in the mandibles, and materials were implanted in 60 male Wistar rats. Each specimen was evaluated histologically after 4 and 8 weeks. The development of fibrous connective tissue in direct apposition to the material was observed in the EBA and IRM groups at 4 weeks. A slight degree of macrophage infiltration was seen in the EBA group. After the 8-week observation period, IRM and EBA were frequently separated from the bone cavity by a fibrous connective tissue layer (p < 0.01). The Base Liner appeared to be in direct apposition to the osseous tissue in several areas (p < 0.01). These findings indicate that Base Liner reacts favorably with osseous tissue, compared with the EBA and IRM materials tested and seems to be a biocompatible material.

PMID: 12772580 [PubMed - indexed for MEDLINE]

[Intratubular penetration of root canal sealers]

Pesqui Odontol Bras. 2002 Oct-Dec;16(4):332-6

Authors: de Deus G, Gurgel Filho ED, Ferreira CM, Coutinho Filho T

The purpose of this study was to evaluate the capacity of penetration of four endodontic sealers (Endo Fill, Sealapex, AH Plus and Pulp Canal Sealer) into dentinal tubules. Seventy-two extracted human maxillary anterior teeth were utilized in this study. The teeth were cleaned and shaped by means of the balanced-forces technique. The work length was established at 1 mm beyond the apex. Copious irrigation with 10 ml of 5.25% sodium hypochlorite was carried out. The teeth were divided in 8 groups - 4 had the smear layer maintained, and 4 had it removed. The smear layer was removed with a commercial solution of 17% EDTA, and the root canal system was flushed for 3 min. Finally, the roots were irrigated with 3 ml of 5.25% sodium hypochlorite. All teeth were sealed by means of the technique of the condensation wave with a medium nonstandardized cone. After filling, the roots were grooved, longitudinally split and examined under a scanning electron microscope (SEM). The focus of observation was the interface between the dentin and the sealing material. The Rickert sealer (Pulp Canal) presented the maximum penetration depths into the dentinal tubules, and Sealapex, the minimum. The Spearman test was used to determine whether there were significant differences between the groups. The removal of smear layer allowed significant penetration of the sealers (p <= 0.01).

PMID: 12612772 [PubMed - indexed for MEDLINE]

Cross-reactivity between gutta-percha and natural rubber latex: assumptions vs. reality.

J Am Dent Assoc. 2002 Oct;133(10):1357-67

Authors: Hamann C, Rodgers PA, Alenius H, Halsey JF, Sullivan K

BACKGROUND: Immunological cross-reactivity between gutta-percha and natural rubber latex, or NRL, has not been demonstrated clearly despite recent concerns and several suspected cases reported in the literature. METHODS: The authors analyzed aqueous extracts of commercial gutta-percha points and raw gutta-percha samples for cross-reactivity to NRL by radioallergosorbent test, or RAST, inhibition; immunoblot inhibition; direct enzyme-linked immunosorbent assay, or ELISA; and ELISA inhibition using sera from NRL-allergic people as the source of anti-NRL immunoglobulin E, or IgE, antibodies. To confirm in vitro results, the authors conducted skin prick testing, or SPT, on a patient with type I NRL allergy using aqueous extracts from raw gutta-percha, ammoniated gutta-percha and gutta-percha points. RESULTS: Aqueous extracts from commercial gutta-percha points did not cross-react to NRL in RAST inhibition or immunoblot inhibition, ELISA or ELISA inhibition assays. However, three of 13 sera from subjects with type I NRL allergy exhibited IgE binding to raw gutta-percha extracts in direct ELISA. Moreover, in ELISA inhibition, the binding of IgE to raw gutta-percha extracts was inhibited in a dose-dependent manner by raw NRL and vice versa. SPT results from a subject with type I NRL allergy were positive for NRL and raw gutta-percha extracts but negative for gutta-percha point extracts. CONCLUSIONS: The authors found no detectable cross-reactivity between NRL and commercial gutta-percha points. However, their ELISA and SPT results demonstrated that some allergenic cross-reactivity exists between raw gutta-percha and raw NRL. CLINICAL IMPLICATIONS: Gutta-percha alone is not likely to induce symptoms in patients with type I NRL allergy. However, other materials used in obturating root canals may be irritating and potentially allergenic in patients with pre-existing allergies.

PMID: 12403538 [PubMed - indexed for MEDLINE]