Prevention efficacy of dentin tubule sealing with Nd:YAG laser against tooth discoloration induced by vital pulp treatment.

BACKGROUND: The discoloration potential of dental materials and applications such as vital pulp therapy also cause discoloration due to the presence of blood. Dentin tubule sealing methods could be used for the prevention of discoloration. AIM: The purpose of this study was to evaluate the effect of sealing pulp chamber walls with Nd:YAG laser against discoloration caused by tricalcium silicate-based materials in the presence and absence of blood contamination. DESIGN: Eighty-one extracted human maxillary incisors were prepared and randomly divided into nine groups according to the Nd:YAG laser application, the cement to be used (NeoMTA Plus/Biodentine), and the presence or absence of blood. The color measurements were obtained with a spectrophotometer at baseline and then at the sixth (T1) and 12th (T2) months thereafter. RESULTS: Sealing with Nd:YAG laser and placing NeoMTA Plus or Biodentine on human blood significantly increased discoloration at T1 and T2 (p < .05). Similarly, without sealing the cavity and placing NeoMTA Plus or Biodentine on human blood significantly increased discoloration at T1 and T2 (p < .05). CONCLUSION: Regardless of sealing the dentin tubules with Nd:YAG laser, NeoMTA Plus and Biodentine caused more discoloration in the presence of blood contamination.

Evaluation of changes in ion release and biological properties of NeoMTA-Plus and Endocem-MTA exposed to an acidic environment.

AIM: To analyse in vitro changes in ion release and biological properties of Endocem-MTA (Maruchi, Wonju, Korea) and NeoMTA-Plus (Avalon Biomed Inc, Bradenton, FL, USA) exposed to acidic or neutral environment on human dental periodontal ligament stem cells (hPDLSCs). METHODOLOGY: Cell viability and wound healing assays were performed using eluates of each material. Cell death and changes in phenotype induced by the set endodontic sealer eluates were evaluated through flow cytometry. To evaluate cell attachment to the different materials, hPDLSCs were directly seeded onto the material surfaces and analysed by scanning electron microscopy. The chemical composition of the materials was determined by energy-dispersive X-ray (EDX), and ion release was evaluated by inductively coupled plasma-mass spectrometry. Statistical analysis was performed with analysis of variance and a Bonferroni or Tukey post-test (α < 0.05). RESULTS: The MTT assay revealed non-cytotoxic effects of NeoMTA-Plus and Endocem-MTA at pH 5.2 and 7.4. However, there were minor differences compared with the control, especially at pH 5.2, where both materials were associated with significantly greater cell viability (P < 0.05). In both environments, the materials stimulated hPDLSCs to migrate. hPDLSCs were attached to the bioactive cements, with multiple prolongations proliferated on the surface of the samples. Moreover, there were no changes to cell phenotype or apoptosis/necrosis rates, indicating that the acidic environment did not induce cell death. Prismatic crystalline structures were seen on the surface of the cements exposed to butyric acid and EDX analysis identified a marked peak of Ca2+ from NeoMTA-Plus and Endocem-MTA in acidic and physiological environments. CONCLUSIONS: An acidic environment favoured the release of Ca2+ ions from both bioactive cements, and the cytotoxicity of these bioactive cements was low in both environments studied.

Properties of NeoMTA Plus and MTA Plus cements for endodontics.

AIM: To test a novel calcium silicate cement mixed with a water-based gel (NeoMTA Plus) with regard to chemical-physical properties and apatite-forming ability. METHODOLOGY: NeoMTA Plus (Avalon Biomed Inc. Bradenton, FL, USA; lot. 2014090301) and a commercial MTA-based material with similar properties (MTA Plus, Prevest Denpro Limited, Jammu, India; lot. 41001) were tested for ion-releasing ability, initial and final setting times, radiopacity, open and impervious porosity and apparent porosity, water sorption, weight loss, solubility, ability to nucleate calcium phosphates (CaP) after immersion in HBSS (Hank's Balanced Salt Solution) by ESEM-EDX and micro-Raman spectroscopy. The results were analysed statistically with the anova test (P  <  0.05). RESULTS: NeoMTA Plus had a prolonged setting time (315 min) and a satisfactory radiopacity (3.76 mm Al). Calcium and hydroxyl ion release was significantly greater and more prolonged in comparison with MTA Plus (P < 0.05). Both NeoMTA Plus and MTA Plus had high values of open porosity and solubility. ESEM-EDX and micro-Raman confirmed the ability to nucleate calcium phosphates on their surface after immersion in HBSS. CONCLUSION: NeoMTA Plus is a new calcium silicate-based cement for root filling with an adequate radiopacity and prolonged setting time. The ion release and CaP-forming ability could increase stability of the root filling and promote endodontic and periodontal tissue regeneration, enhancing the bioactivity and biocompatibility of the material.

Effect of Sodium Hypochlorite on Push-out Bond Strength of Four Calcium Silicate-based Endodontic Materials when used for repairing Perforations on Human Dentin: An in vitro Evaluation.

AIM: This study aimed to evaluate the push-out bond strength of NeoMTA Plus (NMTA), EndoSequence root repair material fast set putty (ERRMF), biodentine (BD), and ProRoot white mineral trioxide aggregate (PMTA) when used as perforation repair materials after exposure to 2.5% sodium hypochlorite (NaOCl) during the early setting phase. MATERIALS AND METHODS: Horizontal midroot sections were prepared from single-rooted human teeth. Sections (n = 144) were randomly divided into four groups: PMTA, BD, NMTA, and ERRMF. Materials were condensed and allowed to set for 10 minutes. The groups were further divided into two subgroups. The NaOCl group included specimens that were immersed in 2.5% NaOCl for 30 minutes, and the control group included specimens on which a wet cotton pellet was placed over the test material. After 48 hours, the highest force applied to the materials at the time of dislodgement was recorded. Slices were then examined under a digital microscope to evaluate the nature of the bond failure. The surfaces of two specimens from each subgroup were observed by scanning electron microscopy. Data were statistically analyzed with two-way and one-way analysis of variances, independent t-tests, and chi-square tests. The statistical significance was set at 0.05. RESULTS: In NaOCl-treated groups, PMTA showed a significantly higher push-out bond strength than the other three materials (p = 0.00). In the control groups, the bond strength of BD was significantly higher than that of PMTA, ERRMF, and NMTA (p < 0.05). Compared with the control group, NaOCl treatment significantly increased the push-out bond strength of PMTA (p = 0.00) and ERRMF (p = 0.00) and significantly reduced the bond strength of BD (p = 0.00) and NMTA (p = 0.03). None of the specimens showed an adhesive type of failure. The majority of the samples exhibited a cohesive failure type. Morphological observations revealed that the surfaces exhibited cubic crystals. In ERRMF, the crystals were few in number. Sodium hypochlorite enhanced the crystallization of NMTA. CONCLUSION: The push-out bond strengths of PMTA and ERRMF were significantly increased after exposure to 2.5% NaOCl in the early setting phase, and those of BD and NMTA were significantly decreased. CLINICAL SIGNIFICANCE: The results of the present study suggest that early exposure of NaOCl increase the push-out bond strength of PMTA and ERRMF. PMTA had the highest push-out values. Therefore, it would be a potentially useful perforation repair material for single visit endodontic treatment.

4-Year Follow-up of Full Pulpotomy in Symptomatic Mature Permanent Teeth with Carious Pulp Exposure Using a Stainproof Calcium Silicate-based Material.

INTRODUCTION: This study aimed to assess the pulpal and restorative outcome of full pulpotomy in symptomatic mature permanent teeth with carious pulp exposure over 4 years. METHODS: Under local anesthesia, full pulpotomy was performed using the aseptic technique and a stainproof calcium silicate-based material (NeoMTA Plus; Avalon Biomed Inc, Bradenton, FL). The pain level was scored preoperatively and at 1 week posttreatment. Clinical and radiographic evaluation was performed at 6 months, 1, 2, and 4 years. Kaplan-Meier survival analysis and Cox proportional hazards regression were used to analyze the data. Failed cases were classified as endodontic or restorative failure. RESULTS: Full pulpotomy was completed in 109 teeth in 90 patients with an age range of 14-60 years (mean = 25 years). The study sample available for follow-up was 100 teeth in 86 patients with a recall rate above 90%. Preoperative pulp diagnosis was reversible pulpitis in 39 teeth and irreversible pulpitis in 61 teeth. The cumulative survival rates of pulpotomy were generally high (ie, 98%, 97.4%, 93%, and 83.8% at 6 months and 1, 2, and 4 years, respectively). The overall mean survival time of pulpotomy was 3.89 years (95% confidence interval, 3.84-3.95). The mean survival time was significantly higher for patients aged ≤25 years. However, in the multivariate analysis, the only significant predictor of pulpotomy failure was severe preoperative pain. Over the 4 years, 23 cases failed; only 10 of 23 failures were classified as endodontic failure, and the success of pulpotomy can be assumed to be 90%. CONCLUSIONS: Full pulpotomy in cariously exposed pulp of mature permanent teeth sustained a high success rate over 4 years. The coronal seal is crucial for long-term survival.

Characterisation of the calcium silicate-based cement-composite interface and the bonding strength with total-etch or single/two-stage self-etch adhesive systems.

Due to favourable biological and physical properties, calcium silicate-based cements (CSCs) are biocompatible materials used widely for vital pulp therapies. Sealing efficacy between the adhesive system and CSC determines the clinical success of treatment. This study aimed to evaluate the shear bond strength (SBS) of CSC to composite resin with different adhesive systems and to analyse the CSC-composite interface. Mineral trioxide aggregate (MTA) (ProRoot MTA; Dentsply Tulsa Dental, Tulsa, OK), Biodentine (Septodont, Saint-Maur-des-Fossés, France) and NeoMTA Plus (Avalon Biomed Inc., Bradenton, FL) samples (n = 90) were placed in the cavities and divided into three subgroups according to the adhesive family (n = 10). SBSs were measured using a universal testing machine. The interfaces were examined using a scanning electron microscope (SEM) (×1000). NeoMTA Plus showed significantly higher SBS values than MTA and Biodentine (P < 0.0001). The application of total-etch adhesive system over Biodentine and NeoMTA Plus provided the statistically highest bond strength (P < 0.05). However, when the SBS values of MTA subgroups were compared, different adhesive families applied over MTA did not make a significant difference in SBS values (P > 0.05). Based on SEM analyses, the specimens exhibit no gaps, cracks or delamination within the adhesive layer, which indicates a good adhesion between the CSC-composite interface in all subgroups. In conclusion, the different adhesive families used over CSC did not influence interfacial gap formation.

Effect of varying durations of intracanal medicament application used in regenerative endodontic treatment on the push-out bond strength of a novel cement: NeoMTA Plus.

AIM: The aim of the present study was to evaluate the effect of varying durations of intracanal medicament application used in regenerative endodontic treatment on the push out the bond strength of a novel cement-NeoMTA Plus. MATERIALS AND METHODS: A total of 60 extracted single-rooted maxillary anterior teeth were decoronated. Roots were instrumented uniformly until Peeso Reamer size #5 to simulate open apices. A total of 60 roots were then divided into four groups according to intracanal medicaments used (n = 15): Group 1: Triple antibiotic paste (TAP); Group 2: Double antibiotic paste (DAP); Group 3: Calcium hydroxide paste (CH); and Group 4 (control): No medicament. Samples were kept in saline solution for 2, 4, and 12 weeks, after which time five roots were selected randomly from each group, representing the samples of each time point. After removal of the medicaments, NeoMTA Plus was placed into 8 mm of the coronal third of the roots and samples were incubated. Roots were sectioned to obtain 2 discs per root (n = 10). A push-out test was used to measure the sealing efficacy of NeoMTA Plus. Data were analyzed using a one-way ANOVA followed by Tukey's pairwise comparisons. RESULTS: CH, DAP, and TAP application resulted in significantly lower values of the push-out bond strength of NeoMTA Plus after 12 weeks compared to 2 weeks (P < 0.05). [Table: see text] No significant differences were found between the time points in the control group (P > 0.05). [Table: see text] DAP showed lowest push-out bond strength. [Table: see text]. CONCLUSION: CH, DAP, and TAP cause an alteration in dentinal surface properties leading to negative effect on bond strength of NeoMTA Plus. The effect is more evident in DAP and as treatment time is prolonged. The type and duration of medicament application have to be monitored to achieve a maximum therapeutic value as well as to avoid compromise on the coronal seal.

Histology of NeoMTA Plus and Quick-Set2 in Contact with Pulp and Periradicular Tissues in a Canine Model.

INTRODUCTION: NeoMTA Plus (Avalon Biomed Inc, Bradenton, FL) is a tricalcium silicate material similar to the first mineral trioxide aggregate product, ProRoot MTA (Dentsply Sirona, York, PA), but with improvements such as decreased setting time, increased ion release, increased water sorption, and nonstaining radiopacifiers. Quick-Set2 (Avalon Biomed Inc) is a newly formulated calcium aluminosilicate material that has a faster setting time and increased acid resistance and is nonstaining. The purpose of this study was to compare the healing of pulpal and periapical tissues in dogs after exposure to NeoMTA Plus and Quick-Set2 after pulpotomy and root-end surgery procedures. METHODS: Seventy-two teeth (36 for each procedure) in 6 beagle dogs received pulpotomy or root-end surgery using either NeoMTA Plus or Quick-Set2. The dogs were sacrificed at 90 days, and the teeth and surrounding tissues were prepared for histologic evaluation. Sixty teeth were evaluated and scored histologically (29 with pulpotomies and 31 with root-end resections). Specimens were scored for inflammation, quality and thickness of dentin bridging, pulp tissue response, cementum and periodontal ligament formation, and apical bone healing. RESULTS: Both materials displayed favorable healing at 90 days. The only significant difference was the quality of dentin bridge formation in pulpotomies using NeoMTA Plus compared with Quick-Set2. CONCLUSIONS: Quick-Set2 and NeoMTA Plus had similar effects on inflammation, pulp response, periodontal ligament and cementum formation, and apical tissue healing in dogs. NeoMTA Plus had superior dentin bridge quality compared with Quick-Set2.

Dentinal Tubule Penetration of Tricalcium Silicate Sealers.

INTRODUCTION: The treatments for which mineral trioxide aggregate (MTA)-based materials can be used in dentistry are expanding. Smaller particle size and easier handling properties have allowed the advent of tricalcium silicate sealers including EndoSequence BC Sealer (Brasseler USA, Savannah, GA), QuickSet2 (Avalon Biomed, Bradenton, FL), NeoMTA Plus (Avalon Biomed), and MTA Fillapex (Angelus, Londrina, Brazil). The objective of this study was to measure the tubule penetration with these sealers using continuous wave (CW) and single-cone (SC) obturation techniques. METHODS: Eighty single-rooted teeth were randomly divided into 8 groups of 10 and obturated with 1 of the previously mentioned sealers mixed with trace amounts of rhodamine using either the CW or SC technique. Teeth were sectioned at 1 mm and 5 mm from the apex and examined under a confocal laser microscope. The percentage of sealer penetration and the maximum sealer penetration were measured. RESULTS: The tricalcium silicate sealers penetrated tubules as deep as 2000 µm (2 mm). The percentage of sealer penetration was much higher 5 mm from the apex, with many specimens having 100% penetration for both SC and warm vertical techniques. MTA Fillapex, a resin-based sealer with less than 20% MTA particles, had significantly greater tubule penetration with a warm vertical technique versus the SC technique at the 1-mm level. CONCLUSIONS: Within the limitations of this study, the CW and SC techniques produced similar tubule penetration at both the 1-mm and the 5-mm level with the tricalcium silicate sealers BC Sealer, QuickSet2, and NeoMTA Plus.