Comparison of preparation design and material thickness on microbial leakage through Cavit using a tooth model system

Biological considerations of dental materials as orifice barriers for restoring root-filled teeth

There is ample published literature regarding the technical aspects of restoring root-filled teeth, but little concerning the biological impacts, consequences, and criteria for the selection of direct restorative materials following endodontic treatment. The provision of an effective coronal seal in addition to a sound root filling is known to be important in the prevention of root canal infection. This review seeks to explore the evidence concerning the selection of dental materials in the restoration of root-filled teeth, specifically with a close examination of the properties of commonly used materials as orifice barriers. © 2023 Australian Dental Association.

Comparative Evaluation of Cotton PTFE Tape and Foam Pellets as Endodontic Spacer in Primary Teeth: An In Vivo Study

Aim and objective

This study was conducted to microbiologically evaluate cotton, PTFE tape, and foam pellets as endodontic spacer in primary teeth.

Materials and methods

Thirty primary second molars indicated for pulpectomy were included in this study. Followed by the completion of pulpectomy in each teeth cotton, PTFE tape, and foam pellets were placed as endodontic spacers randomly in 10 teeth each. The samples were collected from the pulp chamber at baseline and after 7 days to evaluate for microbial contamination of the same. The data obtained was tabulated and subjected to appropriate statistical analysis.

Results

There was a statistically significant increase in the colony forming unit after 7 days in cotton and foam pellet group. But PTFE tape group showed very minimal contamination of the pulp chamber after 7 days.

Conclusion

Within the limitations of this study, it can be concluded that PTFE tape found to be the best alternative to cotton as an endodontic spacer.

Clinical significance

In case of multiple visit pulpectomy procedure, the state of sterility must be maintained in between the appointments until a definitive coronal restoration is placed following root-canal obturation. So it is mandatory to place an endodontic spacer under a provisional restoration to maintain the patency of the root canals and prevention of the microbial growth. The PTFE tape is inorganic, nonfibrous material which can be tightly packed without any voids under the provisional restoration. So PTFE tape is the best material to maintain the root canal patency and to provide a sterile environment by preventing the microbial growth under the provisional restoration as an endodontic spacer material in between the appointments.

How to cite this article

Somani R, Arya MV, Singh DJ, et al. Comparative Evaluation of Cotton PTFE Tape and Foam Pellets as Endodontic Spacer in Primary Teeth: An In Vivo Study. Int J Clin Pediatr Dent 2022;15(1):74-78.

Assessment of bacterial and dye penetration through post/crown interim restorations while under simulated masticatory load

The aim was to compare two temporary cements to determine which resisted bacterial and dye penetration under temporary posts/cores/crowns subjected to simulated masticatory function. Forty-six single canal human tooth roots were prepared for posts/crowns. A cotton pellet and Cavit were placed in each post space. Temporary posts/cores/crowns were cemented with Intermediate Restorative Material (IRM) (n = 23) or Tempocem (n = 23). Specimens were sterilised, then immersed in a mixture of Streptococcus gordonii and India ink, and subjected to 4 weeks simulated mastication. Dye penetration was assessed by visually inspecting the cotton pellets. Bacterial penetration was determined by placing the pellets into sterile broth and by plating them onto agar plates to confirm S. gordonii growth. There was no statistically significant difference between the cements and the dependent variables of bacterial and dye penetration. Hence, both cements are good options to cement temporary posts/cores/crowns during endodontic treatment of anterior teeth.

Coronal Bacterial Penetration after 7 days in class II endodontic access cavities restored with two temporary restorations: A Randomised Clinical Trial

The aim of this in vivo randomised clinical trial was to assess coronal bacterial penetration after placement of Cavit G and IRM temporary restorations in Class II endodontic access cavities. After completion of endodontic treatment, placement of an orifice seal and disinfection of the operating field, sterile cotton pellets were placed in the pulp chamber and the cavities were restored with Cavit G or IRM. After 7 days, coronal and proximal restoration thickness was measured by digital radiographs. Cotton pellet was evaluated by culture methods and polymerase chain reaction assay and bacterial species identified. Bacterial growth was observed in 5 of the 27 (18%) Cavit G samples and in 11 of the 27 (40%) IRM samples which was not significant. Coronal restoration thickness of 4-5 mm and proximal restoration thickness of more than 2.15 mm for Cavit G and 2.35 mm for IRM are recommended to prevent bacterial penetration over 7 days. Adequate restoration thickness is critical to prevent bacterial penetration.

Assessment of Coronal Leakage of Temporary Restorations in Root Canal-treated Teeth: An in vitro Study

INTRODUCTION

Coronal leakage is one of the constant concerns in routine dental practice. It is one of the factors responsible for the failure of root canal therapy. Permanent restorations should be given as soon as possible after the completion of root canal therapy. If unavoidable, provisional restoration should be given in such a way that it maximally reduced the leakage of microorganisms and fluids from the external environment into the canal space. Hence, we evaluated the effect of saliva on the coronal leakage of temporary restorations.

MATERIALS AND METHODS

Biomechanical preparation of the root canals of 204 fresh mandibular first premolar teeth was done using endodontic files with intermittent irrigation of sodium hypochlorite solution and ethylenediaminetetraacetic acid. Alternate irrigation with normal saline was done periodically. After preparation, drying of the canals was done using paper points followed by sealing of the apical foramen. For the assessment of the microleakage, Siqueira et al apparatus and method was used. All the specimens were divided into four groups based on the provisional restorative material used. All the groups were further divided into three subgroups based on the presence and absence of intracanal medicaments. Verissimo et al's criteria were used to check the turbidity at 1-, 2-, 3-, and 4-week interval respectively. All the results were analyzed by Statistical Package for the Social Sciences (SPSS) software. Chi-square test was used to measure the level of significance, and p < 0.05 was considered to be significant.

RESULTS

In group I, all the subgroups' specimens showed significant difference at 1 week's time. Only the subgroup with no intracanal medicaments in Cavit-containing provisional restoration showed nonsignificant alterations. Statistically significant alterations were seen at 1, 2, and 3 weeks' interval in all the subgroups except for one with intracanal medicaments.

CONCLUSION

All the temporary restorative materials were not able to prevent microleakage after 1 week's time, with worst bacterial resistance shown by Ketac Molar and ionomer restorative material. Future studies are advocated for better prognosis of root canal therapy.

Bacterial microleakage of temporary filling materials used for endodontic access cavity sealing

Background/purpose

Providing a tight coronal seal is key for the success of endodontic treatment, therefore the study aimed to assess bacterial microleakage of materials used for short- and long-term temporization.

Materials and methods

One hundred and twenty-eight human upper-third molars were divided into six experimental groups (n = 20) and two control groups: negative (n = 4) and positive (n = 4). The standardized access cavities were prepared and filled with: (1) Cavit; (2) Fuji II LC; (3) Fuji IX; (4) Voco Clip; (5) AdheSE and Tetric EvoCeram; (6) Excite and Tetric EvoCeram. The crown of each tooth was sectioned to obtain 5.5-mm-high disks, which were assembled in a standard setup for bacterial microleakage studies using Streptococcus mutans. The monitoring lasted 90 days. Kaplan-Meier survival analysis was performed.

Results

The lowest amount of leaking samples was found in AdheSE and Tetric EvoCeram (31.3%), Cavit (33.3%), and Excite and Tetric EvoCeram groups (35.3%), followed by Fuji II LC (66.7%), Voco Clip (83.3%). and Fuji IX (88.2%) groups. According to the day of microleakage, materials could be classified in three groups with statistically significant differences (P < 0.05). In the first group were Cavit (70 days), AdheSE and Tetric EvoCeram (68 days), and Excite and Tetric EvoCeram (65 days), in the second group were Voco Clip (44 days) and Fuji II LC (43 days), and in the third group was Fuji IX (21 days).

Conclusion

None of the tested materials were able to completely prevent bacterial microleakage. Adhesively bonded composites and Cavit offer better sealing compared with glass ionomer cements, resin modified glass ionomer cements, and composites without the use of an adhesive system.

In vitro and ex vivo microbial leakage assessment in endodontics: A literature review

The aim of this study was to perform a literature review of published in-vitro and ex-vivo studies, which evaluated microbial leakage in endodontics in the past 10 years. A comprehensive electronic literature search was carried out in PubMed database for English articles published from 2005 to 2016 using the keywords “endodontics,” “in vitro,” “ex vivo,” “microbial leakage,” “microbial penetration,” “saliva,” “Enterococcus faecalis,” “E. faecalis,” “endodontic sealers,” “temporary filling material,” “apical plug,” “mineral trioxide aggregate,” and “MTA.” The keywords were combined using Boolean operators AND/OR. Based on our search strategy, 33 relevant articles were included in the study. There are three main methods for assessment of bacterial microleakage, namely, (A) the dual-chamber leakage model, (B) detection of bacteria using a scanning electron microscope (SEM), and (C) polymerase chain reaction. All bacterial leakage models have some limitations and may yield different results compared to other microleakage evaluation techniques (i.e., dye penetration, fluid filtration, or electrochemical tests). The results of SEM correlated with those of microbial leakage test in most studies. Microbial leakage test using saliva better simulates the clinical setting for assessment of the leakage of single or mixed bacterial species.

Quantitative microleakage analysis of endodontic temporary filling materials using a glucose penetration model

OBJECTIVE

The purpose of this study was to analyze the sealing ability of different temporary endodontic materials over a 6-week period using a glucose penetration model.

MATERIALS AND METHODS

Standardized holes were formed on 48 dentin discs from human premolars. The thicknesses of the specimens were distributed evenly to 2 mm, 3 mm and 4 mm. Prepared dentin specimens were randomly assigned into six groups (n = 7) and the holes in the dentin specimens were filled with two kinds of temporary filling materials as per the manufacturers' instructions as follows: Caviton (GC Corporation, Tokyo, Japan) 2 mm, 3 mm, 4 mm and IRM (Dentsply International Inc., Milford, DE) 2 mm, 3 mm, 4 mm. The remaining specimens were used as positive and negative controls and all specimens underwent thermocycling (1000; 5-55°C). The sealing ability of all samples was evaluated using the leakage model for glucose. The samples were analyzed by a spectrophotometer in quantitative glucose microleakage test over a period of 6 weeks. As a statistical inference, a mixed effect analysis was applied to analyze serial measurements over time.

RESULTS

The Caviton groups showed less glucose penetration in comparison with the IRM groups. The Caviton 4 mm group demonstrated relatively low glucose leakage over the test period. High glucose leakage was detected throughout the test period in all IRM groups. The glucose leakage level increased after 1 week in the Caviton 2 mm group and after 4 weeks in the Caviton 3 mm and 4 mm groups (p < 0.05).

CONCLUSIONS

Caviton had better sealing ability than IRM in the glucose penetration model during 6 weeks. Temporary filling of Caviton to at least 3 mm in thickness is necessary and temporary filling periods should not exceed 4 weeks.

Bacterial and dye penetration through interim restorations used during endodontic treatment of molar teeth

INTRODUCTION

The purpose of this study was to investigate the association between dye and bacterial penetration through interim restorations used during endodontic treatment.

METHODS

Sixty-four extracted human teeth were used, with 2 teeth each as positive and negative controls. Endodontic access with a mesio-occluso-distal cavity was prepared. Palatal cusps of maxillary molars and buccal cusps of mandibular molars were removed. Cotton was placed over the canals and covered with Cavit. Thirty teeth were restored with Ketac Silver (KS) and 30 with KS reinforced with a stainless steel band (KSSB). Samples were submersed in India ink mixed with brain heart infusion broth containing Streptococcus gordonii. After 3 months of simulated chewing, structural integrity and dye and bacterial penetration were assessed.

RESULTS

Positive controls had both dye and bacterial penetration. Negative controls had no dye or bacterial penetration. All KS restorations debonded, whereas 18 KSSB restorations (60%) debonded. KS restorations were 1.67 times more likely to debond than KSSB restorations (Fisher exact test). KS was 1.3 times more likely to have dye penetration than KSSB (Fisher exact test) and 3 times more likely to have bacterial penetration, although not statistically significant (chi(2) test). Overall, 88.3% of specimens had dye penetration, and 20% had bacterial penetration. This 68.3% difference indicated no association between dye and bacterial penetration (exact McNemar test).

CONCLUSIONS

Stainless steel bands helped maintain structural integrity of KS restorations under masticatory function. Bands helped prevent dye penetration but not bacterial penetration. There was no association between dye and bacterial penetration.