Porosity and sealing ability of root fillings with gutta-percha and BioRoot RCS or AH Plus sealers. Evaluation by three ex vivo methods.

AIM: To investigate the ability of BioRoot RCS, a tricalcium silicate-based root canal sealer and AH Plus to effectively fill the root canals of contralateral teeth using three evaluation methods, and to investigate also the correlation between the methods. METHODOLOGY: The prepared root canals of ten pairs of contralateral mandibular premolar teeth were filled with gutta-percha and sealer using lateral compaction. The percentage of voids within the root canal was assessed by micro-computed tomography, whilst sealing ability was investigated by fluid transport and leakage of fluorescent microspheres. The interaction of sealer with dentine, and sealer penetration were assessed by confocal microscopy. The void volume, fluid flow, microsphere leakage and sealer interaction with dentine for both materials were compared. Nonparametric (Mann-Whitney) tests were used to compare the % void and fluid transport of the two sealers. Spearman correlation was used to assess the pairwise relationships between the techniques. The level of significance was set to 0.05. RESULTS: BioRoot RCS exhibited significantly more percentage of voids than AH Plus. There was no difference in fluid flow and microsphere penetration. BioRoot RCS exhibited a different pattern of sealer penetration and interaction with the dentine walls compared to AH Plus. For both materials, the pairwise correlations between the three techniques were close to zero, indicating weak relationships. CONCLUSIONS: MicroCT analysis revealed a higher void volume for BioRoot RCS. The other techniques did not show a difference between the sealing ability of the sealers. The correlation between the three ex vivo methods of assessment was weak demonstrating their complementarity rather than their concordance.

Sealing efficacy of a single-cone root filling after post space preparation.

OBJECTIVES: The aim of the present study was to compare the sealing efficacy of root fillings made by a single-cone technique with three different sealers and a cold lateral compaction technique with an epoxy sealer. MATERIALS AND METHODS: Eighty extracted single-rooted human teeth were assigned to four experimental groups: group 1, single-cone and epoxy sealer; group 2, single-cone and calcium silicate-based sealer; group 3, single-cone and methacrylate resin-based sealer; and group 4, cold lateral compaction and epoxy sealer. Twenty extra teeth served as negative and positive controls. After preparation of a coronal post space, the sealing efficacy of the root fillings was assessed on a fluid transport setup. The results were analyzed using Kruskal-Wallis and Mann-Whitney U test. RESULTS: No fluid transport was detected for the negative controls whereas all the positive controls showed rapid fluid transport. No significant difference was detected between groups 1, 3, and 4 whereas group 2 demonstrated significantly more fluid transport than all the other experimental groups. CONCLUSIONS: Root fillings made by a single-cone technique with the epoxy or methacrylate-based sealers were as effective after post space preparation as those made by a cold lateral technique with the epoxy sealer in sealing the root canal. CLINICAL RELEVANCE: Specific root canal sealers in combination with single-cone technique represent a noteworthy alternative to the use of cold lateral compaction technique when a post space is required. The use of effective endodontic procedures with simplified technical implementation may positively affect endodontic outcome.

[Endodontics in motion: new concepts, materials and techniques 1. Hydraulic Calcium Silicate Cements]. / Endodontologie in beweging: nieuwe concepten, materialen en technieken 1. Hydraulische calciumsilicaatcementen.

Hydraulic Calcium Silicate Cements (HCSCs) constitute a group of materials that have become increasingly popular in endodontics since the introduction of Mineral Trioxide Aggregate (MTA) in the 1990s. MTA is Portland cement to which bismuth oxide has been added to increase its radiopacity. The most important property of MTA is its capacity to set in water or a humid environment. However, MTA also has important limitations, for example, it's difficult to work with and can discolour teeth. Recently, numerous products based on HCSC chemistry, which can be considered as modifications of MTA intended to reduce its limitations, have become available on the market. Despite their potential advantages, all of these materials have their own specific limitations that are currently insufficiently known and investigated.

The correlation between fluid transport and push-out strength in root canals filled with a methacrylate-based filling material.

AIM: To investigate the correlation between fluid transport and dislocation resistance in canals filled with a methacrylate-based filling material. METHODOLOGY: The root canals in sixty-five single-rooted human teeth were prepared to size 40, 0.06 taper. Sixty roots were filled with a single-cone technique using RealSeal SE sealer and divided into 3 groups, whilst five roots served as fluid transport positive control. Group 1 (n = 20): correlation group. Specimens were consecutively tested with fluid transport for 90 min and thereafter with the push-out test at coronal and apical root levels. Group 2 (n = 20): push-out control. Specimens were only subjected to the push-out test at coronal and apical root levels. Group 3 (n = 20): fluid transport negative control. Specimens were totally covered with nail varnish. The correlation between fluid transport and dislocation resistance was assessed by Kendall's tau-b coefficient. The Mann-Whitney U-test was used to compare dislocation resistance between groups 1 and 2 and fluid transport between groups 1 and 3. Significance level was set at P < 0.05. RESULTS: Kendall's tau-b correlation coefficients between fluid transport and dislocation resistance were weak, being coronally 0.139 (P = 0.444) and apically -0.080 (P = 0.658). No significant difference in dislocation resistance could be detected between groups 1 and 2 at both root levels (P = 0.052 and P = 0.336, respectively). CONCLUSION: No significant correlation could be identified between fluid transport and dislocation resistance, meaning that the corono-apical sealing ability of a methacrylate-based root canal filling is independent of its adhesive properties as indicated by its dislocation resistance.

Bisphosphonates and their clinical implications in endodontic therapy.

This review gives an overview of the factors that may play a role in the development of osteonecrosis of the jaw in patients treated with bisphosphonates (BPs) and undergoing nonsurgical endodontic treatment as well as some recommendations for its prevention. BPs are a widely prescribed group of drugs for diverse bone diseases. The occasional but devastating adverse effect of these drugs has been described as bisphosphonate-related osteonecrosis of the jaw (BRONJ). As this condition is debilitating and difficult to treat, all efforts should be made to prevent its occurence in patients at risk. The main triggering event is considered to be dental extraction. Even though nonsurgical endodontic treatment appears to be a relatively safe procedure, care remains essential. After an overview of this class of drugs, the clinical presentation, epidemiology and pathogenesis of BRONJ, as well as the possible risk factors associated with its development after nonsurgical endodontic treatment will be described. Finally, several strategies will be proposed for the prevention of BRONJ during nonsurgical endodontic treatment.