An assessment of microbial coronal leakage of temporary filling materials in endodontically treated teeth

This in vitro study evaluated the microbial leakage of Cavit, IRM, and Dyract when used as temporary filling materials after root canal treatment. The degree of coronal leakage was assessed by using a microbiological marker consisting of Streptococcus faecalis and Candida albicans. For each of the two organisms, a set of 15 maxillary premolars were prepared chemomechanically and obturated with thermoplasticized gutta-percha. A 3.5-mm thick layer of one of the three temporary filling materials was inserted in the access cavities of the teeth from each group (each group was compromised of five teeth). The control teeth (four positive and four negative) lacked any filling material over the gutta-percha, whereas the orifice and the apical foramen of the negative control were completely sealed with nail polish. Each tooth was placed in a well of a 24-well tissue culture plate and embedded in trypticase soy broth and 0.5% Bactoagar. An organism suspension was inoculated in the access cavity, and microbial penetration was detected as an increase in turbidity of the broth. At the end of 30 days, the results showed that all positive control teeth leaked within 1 week, whereas those that served as negative control remained uncontaminated throughout the test period. With both organisms, IRM started to leak after 10 days, whereas Cavit and Dyract leaked after 2 weeks.     

A laboratory study of coronal microleakage using four temporary restorative materials

AIM: The aim of this study was to compare the sealing abilities of Fermin and Canseal with the more popular temporary coronal filling materials, Cavit and Caviton. METHODOLOGY: Standardized access cavities were prepared in 160 intact human permanent molar teeth. They were divided into five groups consisting of 32 samples. The teeth were restored using one of the temporary filling materials, namely: Fermin, Canseal at two powder to liquid ratios, Caviton and Cavit. Thermal cycling and/or load cycling were applied on the samples. Assessment of microleakage utilized methylene blue dye penetration. Grading of the microleakage pattern was from 1 to 3, with 3 providing the best seal. Results were analyzed using two-way anova and by Fisher's PLSD post hoc test (P < 0.05). RESULT: Microleakage along Fermin, Caviton and Cavit samples did not go beyond Leakage Grade 2. Dye penetration into these materials was noted. This was not observed in the two groups of Canseal tested. However, the two groups of Canseal exhibited total leakage notably after being subjected to thermal cycling. There was a statistically significant difference in the microleakage scores obtained between the materials and conditions tested (P < 0.0001). CONCLUSION: Fermin was found to exhibit the best seal amongst the four materials tested followed by Caviton, and Cavit. Thermal cycling influenced the seal of certain types of temporary filling materials more than load cycling.     

Bacterial microleakage of Cavit, IRM, TERM, and Fermit: a 21-day in vitro study

The aim of our study was to evaluate the leakage of four cements (Cavit, IRM, TERM, and Fermit) using a two-compartment model system and Streptococcus sanguis as bacterial marker. Access cavities in premolars were filled with cement and the teeth immersed in culture medium in the model system. Half of the teeth were thermocycled on day 2. Bacterial percolation into the upper compartment was measured at regular intervals (days 2, 7, 14, and 21). Cement thickness was measured at the end of the study. In the nonthermocycled group, Cavit was more leakproof than the other cements at day 2 (p = 0.011), than TERM and IRM at day 7 (p = 0.043). Fermit was more leakproof than IRM at day 7 (p = 0.043). In the thermocycled group, Cavit was more leakproof than the other cements at day 7 (p = 0.041). Thermocycling did not significantly affect leakage. Cement thickness averaged 4.1 mm and did not significantly affect leakage. These results should be considered when using cements as temporary fillings.     

Coronal microleakage of three temporary restorative materials: an in vitro study

The sealing properties of three temporary restorative materials, Cavit, IRM, and a polycarboxylate-based cement, Ultratemp Firm, were investigated in vitro. Standardized access cavities were prepared in 45, intact, extracted, human molars. The teeth were randomly assigned to three groups and the access openings filled with one of three temporary filling materials. In five teeth (negative control), no restorative material was placed but the preparations were coated entirely with sticky wax. The five teeth of the positive control group had no restorative material and no sticky wax applied. After thermocycling for 500 cycles (5-55 degrees C), the experimental teeth were dipped in molten sticky wax to the CEJ. The coronal enamel was subsequently coated with two layers of nail varnish, leaving an area of 1 mm around the filling material uncovered. The samples were then immersed in 2% methylene blue dye solution for leakage assessment. The teeth were sectioned and the greatest depth of dye penetration was recorded. Positive control sections exhibited complete dye penetration, whereas negative controls had none. There was no statistically significant difference in marginal leakage between Cavit, IRM, and Ultratemp Firm (p > 0.05). All materials leaked at the interface material-dentin, whereas some IRM specimens absorbed the dye into the bulk of the material.     

Sealing ability of intermediate restorations and cavity design used in endodontics

Temporary filling materials are used in endodontics to prevent contamination of the root canal system during intertreatment visits. Recently, a new composition resin (TERM) has been introduced as an interim restoration in endodontics. The purpose of this investigation was to evaluate the efficacy of this resin as an interim restoration and possible effect of access cavity design with respect to its sealing ability compared with other temporary restorative materials. Sixty human teeth were divided into two categories, and two types of access cavities were prepared, namely tapered access with walls divergent toward the occlusal surface and straight access with parallel walls. The prepared teeth from each category were divided into three subgroups of ten each to receive Cavit (group I), IRM (group II), or TERM (group III). After the fillings were placed, the teeth were transferred into a humidor where they stayed for 24 hours. The teeth were then thermocycled. Each group was thermocycled for 2 hours at 1 minute intervals at 60 degrees C and 4 degrees C. Then the teeth were sealed with a compound and coated with two layers of clear varnish, with the exception of cavity margins. Each occlusal surface was immersed in a vial containing silver nitrate. The teeth were sectioned longitudinally, and the degree of dye penetration was evaluated under a dissection microscope according to set criteria. Our findings demonstrated that design of cavity preparation was not a functional parameter in leakage pattern. Results indicated that Cavit had the best sealing ability whereas IRM showed the maximum dye penetration.     

Comparative in vitro coronal microleakage study of new endodontic restorative materials

Complete sealing of endodontic access openings between appointments and after completion of therapy is an essential element in achieving endodontic success. Recently, two new products for use as temporary restorative materials, TERM and Dentemp, have become available. The purpose of this study was to compare in vitro the sealing ability of Cavit, Cavit-G, Cavit-W, and IRM-Caps, with TERM, Hard-TERM, and Dentemp. Standard access cavities were prepared in 144 intact extracted human teeth. They were equally and randomly distributed into seven groups, and their access openings were temporized. Specimens were submitted to thermocycling (5 to 55 degrees C) for 7 days and stained with silver nitrate. The teeth were split in half, and the greatest depth of dye penetration at the tooth surface was recorded. TERM exhibited the least leakage, while Hard-TERM demonstrated the greatest leakage, at the tooth-restoration interface.     

Microleakage of different types of temporary restorative materials used in endodontics

A temporary filling should seal the endodontic access cavity to avoid reinfection of the root canal system during endodontic treatment. The aim of this study was to evaluate the marginal seal of four temporary filling materials in endodontic access cavities in vitro, using the dye penetration method. Endodontic access cavity preparations were in 50 incisor and 50 molar noncarious nonrestored crowns of extracted human teeth. The coronal access of 10 teeth per group were filled with Coltosol, Algenol, IRM, Fermit or Fermit-N. After storing the teeth in demineralized water for 48 hours, they were immersed in 2% methylene blue dye for 24 hours. All the teeth were sectioned longitudinally and the linear depth of dye penetration was evaluated under a stereomicroscope. There was no significant difference in the microleakage observed in the high elasticity light-cured resin composite (Fermit) versus the low elasticity light-cured resin composite (Fermit-N) groups (p > 0.05).     

Sealing quality of a temporary filling material.

Endodontic access cavities were prepared in forty extracted human teeth. The access cavities were obturated with Cavit and tested for leakage with methylene blue. The data suggested that at least a 3.5 mm. thickness of Cavit should be used in order to prevent leakage. Examination under the scanning electron microscope showed areas in which the constituents of Cavit were improperly mixed, which may lead to increased penetration.     

Bacterial microleakage of Cavit, IRM, and TERM.

In this in vitro study, a model system was developed and tested to evaluate the sealing ability of temporary restorative materials used in endodontic access preparations. The materials studied, Cavit, IRM, and TERM, were tested on 40 premolars against a known bacterial species, Streptococcus sanguis. The leakage of bacterial cells was checked 4 and 8 days after initial immersion in the culture. Thermocycling was introduced on the fourth day. After 8 days the cement thicknesses were measured after the teeth had been longitudinally sectioned. Before and after thermocycling, IRM was less leakproof than Cavit (p < 0.05) and TERM (p < 0.05). Thermocycling aggravated percolation in the case of IRM, and decreased the tightness of Cavit, whereas TERM remained leakproof. The thicknesses were as follows: Cavit, 3.73 mm; IRM, 3.45 mm; and TERM, 5.49 mm. There was no statistically significant relationship between thickness and tightness.     

In vitro study to compare the coronal microleakage of Tempit UltraF, Tempit, IRM, and Cavit by using the fluid transport model

An adequate coronal seal is critical for the success of root canal therapy. The purpose of this study was to assess and compare the coronal microleakage of 4 temporary filling materials used to seal the access cavity in root canal treated teeth. Standardized access cavities were prepared in 55 extracted human, single canal teeth. They were instrumented by using a crown-down method to a size 45 file. The smear layer was removed with a 1-minute soak with 17% ethylenediaminetetraacetic acid followed by a 10-minute soak with 5.25% NaOCl and dried with paper points. All roots were obturated with gutta-percha and AH Plus sealer by using the continuous wave of condensation technique. The teeth were randomly divided into 4 groups of 10 teeth, with the remaining teeth serving as positive and negative controls. The access openings of the teeth in the experimental groups were filled with 4 mm of Cavit, IRM, Tempit, or Tempit-Ultra-F. All teeth were stored in 100% humidity at 37 degrees for 10 days, allowing sealer to set before testing. After thermocycling for 500 cycles (5 degrees C-55 degrees C), microleakage was measured by using the fluid transport model at 10 psi. All materials tested leaked. Kruskal-Wallis and Mann-Whitney U analysis indicated significantly less leakage (P < .05) with Tempit UltraF compared with Cavit and IRM. There were no statistically significant differences between Tempit Ultra-F and Tempit or between Cavit, IRM, and Tempit.     

Assessment of coronal microleakage of three materials used in endodontically treated teeth

This study compared the coronal microleakage of three restorative materials used to seal the access cavity in root treated teeth. Thirty six teeth were prepared and three experimental groups were obturated and the access cavity filled with different materials; Group A--Intermediate Restorative Material, Group B--Fuji II and Group C--Dyract AP. Microleakage was assessed by Indian ink penetration. The mean coronal dye leakage for Group A was 0.895 mm, for Group B 1.914 mm and for Group C 3.245 mm. There was significantly (p < 0.05) more dye leakage in teeth restored with Dyract AP compared to those with Fuji II or IRM.     

A microleakage study of temporary restorative materials used in endodontics

The purpose of this study was to quantitatively evaluate the sealing properties of various temporary restorative materials used in standard endodontic access preparations by using a newly introduced fluid filtration method. The materials tested were Cavit, Cavit-G, TERM, glass ionomer cement, zinc phosphate cement, polycarboxylate cement, and IRM. Extracted human incisor, canine, and premolar teeth were used, and each tooth served as its own control by testing for microleakage prior to access preparation. Following access preparation, cotton pellets were placed in the pulp chamber so that the space remaining for the restoration was 4 mm. Immediately after placement of the restoration, the teeth were immersed in Ringer's solution and incubated at 37 degrees C. Microleakage was measured after various time intervals. The results indicated that Cavit, Cavit-G, TERM, and glass ionomer cement provided leakproof seals during the 8-wk testing period, while leakage was observed in 4 of the 10 teeth restored with zinc phosphate cement. IRM and polycarboxylate cement were the least effective of the materials tested for preventing microleakage.     

Leakage in roots coronally sealed with different temporary fillings

This study was aimed at determining the ability of different coronal temporary fillings to prevent corono-apical penetration of bacteria. A total of 103 human teeth, including three controls, were instrumented, obturated with gutta-percha, coronally sealed with either Cavit, Intermediate Restorative Material (IRM), glass-ionomer cement, Cavit/glass-ionomer cement, or IRM/glass-ionomer cement, respectively. Each root was fixed with wax between two chambers: the coronal chamber harboring soy broth with 10(8) colony-forming units of Streptococcus mutans/ml, the apical chamber containing sterile soy broth. The latter was checked daily for turbidity, indicating corono-apical penetration of bacteria. The Cavit group, the IRM group, and the Cavit/glass-ionomer cement group showed significantly more leakage than the glass-ionomer cement group of the IRM/glass-ionomer cement group. If a sample leaked, all except one (IRM/glass-ionomer cement) leaked before day 12. This in vitro study seems to indicate that only glass-ionomer cement and IRM combined with glass-ionomer cement may prevent bacterial penetration to the periapex of root-filled teeth over a 1-month period.     

Leakage of food-borne Enterococcus faecalis through temporary fillings in a simulated oral environment

AIM: To evaluate the hypothesis that food-borne viable Enterococcus faecalis cells could enter the root canal space via coronal leakage. METHODOLOGY: In a simulated oral environment under mastication the capacity of a calcium sulphate-based temporary filling material (Cavit W) to prevent leakage of E. faecalis from a cheese through the endodontic access cavity into the pulp chamber was assessed. Standardized class I access cavities were prepared in human maxillary molars. These were filled with Cavit of either 2 or 4 mm thickness (n=16, each). Empty access cavities served as positive, teeth filled with a light-curing composite material acted as negative controls (n=8, each). A cheese containing viable E. faecalis cells was placed on the occlusal aspects of test and control teeth, which were subsequently subjected to 680 mastication loads per day for 1 week in a masticator device perfused with artificial saliva at 37 degrees C. Leakage of E. faecalis from the cheese into the pulp chamber was assessed by culture on a kanamycin aesculin azide agar and compared between groups using Fisher's exact test. RESULTS: All of the positive controls showed pure growth of E. faecalis. In addition, one of the negative control teeth leaked. The 4 mm application of Cavit prevented leakage of E. faecalis significantly better than the corresponding 2 mm application: 1 of 16 specimens compared with 6 of 16 specimens had leakage, respectively (P<0.05). CONCLUSIONS: The current results substantiate the suspicion that food-derived microbiota could enter the necrotic root canal system via microleakage.     

Marginal leakage of different temporary restorations in standardized complex endodontic access preparations

This study compared the marginal leakage of temporary restorations using Cavit, IRM, zinc phosphate cement (ZPC), and copper bands cemented with ZPC. Standardized complex endodontic access preparations were made in 176 extracted human molars. The teeth were divided into six groups, including positive and negative controls. A Universal matrix system was placed over each tooth before restoration, except in the copper band group, in which teeth were restored with ZPC after copper band cementation. Marginal leakage was evaluated with a binocular microscope after the teeth were immersed in artificial saliva, colored with 2% methylene blue and buffered to neutral pH, at 37 degrees C for various time intervals after thermal cycling. In the experimental groups, the differences in the leakage scores of the Cavit group and the other groups were very marked. The Cavit group presented the least marginal leakage, irrespective of time, whereas more than half the specimens from the IRM, ZPC, and copper band groups displayed severe leakage from day 1.     

In vitro inhibition of caries-like lesions with fluoride-releasing materials

The aim of this study was to compare the in vitro caries inhibition of various resin-based materials. Class V cavities were prepared in twenty-five freshly extracted human premolar teeth which were then restored with glass-ionomer cement (Chemfill II), compomer (Compoglass F, Dyract AP) and composite resin (Tetric Ceram and Z 100). The teeth were submerged in an acid gel for 6 weeks. Each specimen was sectioned. These sections were left in water for 24 hours, and then examined using polarized light microscopy. The lesion consisted of two parts, the outer surface lesion and the cavity wall lesion. There was no significant difference in the body depth of the outer lesion and in the depth of the wall lesion among teeth restored with Compoglass F, Dyract AP and Chemfill II (P > 0.05). There was a significant difference between those restored with Z 100 and Tetric Ceram (P < 0.05). The length of the wall lesion for the teeth restored with Chemfill II was significantly smaller than that in the remaining groups (P < 0.05). The length of the wall lesion for teeth restored with Tetric Ceram and Z 100 was significantly higher than in the remaining groups (P < 0.05). These results suggest that composite materials and compomer provide less caries inhibition than glass-ionomer cements.     

Sealing ability of three materials in the orifice of root canal systems obturated with gutta-percha

There were 130 single roots randomly assigned to one of 12 experimental or two control groups. Forty specimens each were sealed with 1, 2, 3, or 4 mm of Cavit, ProRoot MTA, or Tetric. After creation of a uniform orifice diameter, the smear layer was removed and the canal systems obturated using warm lateral compaction of gutta-percha (GP). GP was removed to the experimental depth, experimental materials placed in the orifice, and roots submerged in India ink in a vacuum flask. Specimens were demineralized and leakage measured using a 10x stereomicroscope and graded for depth of leakage by one calibrated, blinded rater. There was no significant interaction (p > 0.05) between test materials and orifice depths, nor main effect of orifice depth (p > 0.05). However, there was a statistically significant main effect of test materials with Tetric demonstrating a significantly better seal than Pro Root or Cavit (p < 0.0001) irrespective of orifice depth.     

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

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.     

In vivo study of temporary filling materials used in endodontics in anterior teeth.

The sealing efficacy of temporary endodontic filling materials was tested in vivo. The following materials were studied: Cavit, Caviton, gutta-percha, three types of zinc phosphate cement, and zinc oxide and eugenol. All the materials were tested in the access cavity of the same anterior tooth in ten different patients for a minimum of 1 week. Seepage was determined bacteriologically by culturing a cotton pellet which was sealed into the access cavity. On the basis of the quantity of microorganisms grown anaerobically, differentiation was made between no leakage, minor leakage, and gross leakage. Findings with Cavit and Caviton are essentially the same and show no or minor leakage in the vast majority of tests. Gutta-percha showed gross leakage in six out of eight tests. Phosphate cements showed no leakage in more than two thirds of the tests.     

A comparison of two temporary restorations: light-cured resin versus a self-polymerizing temporary restoration

Temporary restorative materials are an important component of endodontic therapy. They must both adequately seal the access preparation between visits and protect the obturated canal(s) from microleakage until a permanent restoration can be placed. The efficacy of Cavit and T.E.R.M. (a new light-cured composite product) was compared with the use of a carbon black coronal microleakage protocol. The teeth examined had previously received coronal restorations. After the teeth were accessed, restored with Cavit or T.E.R.M., and exposed to the dye, they were cleared. Three-dimensional assessment then revealed that Cavit more consistently provided an effective seal. In addition, a great deal of microleakage was observed around the permanent restoration-tooth interface. This indicates that perhaps leaking permanent restorations should be removed in their entirety before initiation of endodontic treatment.