Evaluation of the Sealing Ability of Direct versus Direct-Indirect Veneer Techniques: An In Vitro Study

Backgrounds. Marginal discoloration, microleakage, wear, and marginal fractures are all prevalent problems with composite veneers, and this scenario leads the esthetic outcome to deteriorate with time, resulting in patient discontent. Aim of the Study. The study’s goal was to determine the marginal sealing ability of composite laminate veneers when employing two types of veneer techniques: direct and direct-indirect veneers, as well as two types of composite resin: nanohybrid and microfilled composite resin restorations, using dye penetration method. Materials and Methods. In this study, forty extracted human teeth were utilized. Following a standardized veneer preparation on the labial surface of the teeth, they were separated into two groups of 20 teeth each, using the following composite application techniques: group A: direct veneers and group B: direct-indirect veneers. Following that, each major group was separated into two subgroups of ten teeth each, based on the type of composite employed: subgroup 1 used nanohybrid composite resin, while subgroup 2 used microfilled composite resin. All of the samples were kept in distilled water, thermocycled, and soaked in 2% basic fuchsine dye. These specimens were sectioned and examined under a stereomicroscope for dye penetration at the gingival margin. The data was analyzed using independent T -tests using SPSS 22. Result. Using direct-indirect veneer technique with nanohybrid composite resin material resulted in the most negligible dye penetration at the gingival margin, while using direct veneer technique with microfilled composite resin material resulted in the maximum dye penetration. For both composite materials, gingival microleakage was lower when using the direct-indirect veneer technique than when using the direct technique, and the difference was statistically significant ( P < 0.05 ). In both techniques, gingival microleakage was lower with nanohybrid composite than with microfilled composite, and the difference was statistically highly significant ( P = 0.001 ). Conclusion. The sealing ability of the gingival margin of tooth/composite interface is better when applying direct-indirect veneer technique with nanohybrid composite resin than that of direct veneer technique with microfilled composite resin material.

Comparison of Root End Sealing Ability of Three Retrograde Filling Materials in Teeth with Root Apices Resected at 90° using Dye Penetration Method under Fluorescent Microscope: An In-vitro Study

Background: Inadequate seal at the apex is the substantial cause for surgical endodontic dissatisfaction. The retrograde filling material which is used should prevent the egress of potential contaminants into periradicular tissue. Objectives: To evaluate the ability of MTA Angelus, Zirconomer and Bioactive bone cement to seal the root end as retrograde filling material; and to compare root end sealing ability of these three different retrograde filling materials with apices resected at 900 angles using dye penetration method under fluorescent microscope. Methodology: Thirty six extracted upper anterior teeth are to be cut horizontally at the CEJ. After following the standard protocols of, “cleaning, shaping and obturation” with gutta percha and “AH Plus sealer”, the samples will be resected 3mm at the apical end at 90 degree angle along the long axis of the tooth with the help of diamond disc. A root end cavity of depth 3mm will be made with Diamond coated ultrasonic surgical tip S12 90 ND. The teeth will be randomly categorized in 3 groups: Group 1: MTA angelus; Group 2: Zirconomer; Group 3: Bioactive Bone Cement. Following which the roots to be coated with nail varnish except the tip. Each material will be compressed in the root end cavity with the help of small pluggers. All the samples which are retrofilled will be kept in acrydine orange for a duration of 24 hours, following which cleaning & bucco-lingual sectioning(vertical) will be done. Fluorescent microscope will be used for observation of sectioned root samples. Expected Results: Bioactive bone cement is expected to have better sealing ability of the retrograde cavity preparation with minimal or no microleakage followed by MTA Angelus and then Zirconomer. Conclusion: If this study proves correct, this would be helpful for the clinicians to choose better and the most efficient retrograde filling material with best sealing ability and minimal microleakage in a retrograde preparation which will aid in success of the root canal treatment further resolving the infection.

Apical Sealing Ability of Two Calcium Silicate-Based Sealers Using a Radioactive Isotope Method: An In Vitro Apexification Model

The aim of this study was to evaluate and compare the sealing ability of two calcium silicate-based sealers (TotalFill BC RRM Fast Set Putty and White ProRoot MTA) when used as apical plugs in immature teeth through nuclear medicine. Single-rooted extracted teeth (n = 34) had their crowns and root tip sectioned to obtain 14 mm long root segments to simulate an in vitro apexification model. Were created two experimental groups, namely MTA (n = 12) and BC (n = 12), and two control groups, PG (positive group, n = 5) and NG (negative group, n = 5). On the 4th day after placing the respective apical plug, the apical portions of the teeth were submerged in a solution of sodium pertechnetate (99mTcNaO4) for 3 h. Statistical analysis showed a significant difference between the MTA group and the controls (p < 0.05). The BC group had a significant difference regarding the negative control (p < 0.001) but showed no statistical significance regarding the positive control (p = 0.168). There was a statistically significant difference (p = 0.009) between the BC group (7335.8 ± 2755.5) and the MTA group (4059.1 ± 1231.1), where the last showed less infiltration. Within the limitations of this study, White ProRoot MTA had a significantly better sealing ability than TotalFill BC RRM Fast Set Putty.

Novel microwave surgical instrument for use in various lung resection situations

A novel surgical energy device with high sealing ability using microwave technology has been developed. This novel microwave surgical instrument (MSI) is capable of sealing and dissecting a vessel ≤ 5 mm in diameter. The high sealing ability of the MSI enables fine dissection of the lung parenchyma by a scissor-type blade. This device is particularly useful in situations wherein the use of an automatic suturing instrument is difficult. Here, we describe the dissection of the lung parenchyma using this device in three patients (cases 1–3). This device was used for wedge resection of a tumor located close to the pulmonary hilum, for subsegmentectomy, and for dividing incomplete interlobar fissure (cases 1–3, respectively). In all the cases, the postoperative course was uneventful. This MSI is effective for resection of the lung parenchyma, allowing fine tissue dissection and excellent tissue sealing. This technique could assist surgeons in various lung resection cases.

An Evaluation on Sealing Ability of Calcium Silicate-Based Cements and Glass Ionomer Cement as Perforation Repair Materials

Aims: The study evaluated the sealing ability of Biodentine, MTA Repair HP, and Glass ionomer cement as perforation repair materials by using a Stereomicroscopic analysis. Study Design: Experimental in vitro study Methodology: The access cavity was prepared on 45 samples of maxillary and mandibular teeth with a perforation of the standardized diameter of a No. 2 round bur at the bottom of the pulp chamber. All 45 samples were divided into three different experimental groups of 15 samples each. Group A (n=15), Group B (n=15) and Group C (n=15). The furcation repairs of the samples in groups A, B and C were carried out using Biodentine, MTA Repair HP and glass ionomer cement respectively. All sealed furcation perforation samples were stored at room temperature for 24 hours. Two layers of nail varnish were coated on all the surfaces to avoid dye penetration except for 2 mm around the area of the perforation site. After complete drying, all specimens were separately soaked in 2% methylene blue solution for 48 hours, cleaned with water and dried for 24 hours. They were sectioned buccolingually. The perforation wall of the sectioned sample with the greatest dye penetration was selected for microleakage analysis. Results: The collected data from the three experimental groups were subjected to statistical analysis using one-way analysis of variance and Tukey's post hoc test for multiple comparisons of mean differences in dye penetration. The Biodentine group had the significantly lowest dye penetration length compared with the MTA Repair HP and glass ionomer cement groups (P<0.001). Conclusion: Biodentine showed better sealing ability as a repair material for furcation perforations compared to the other two materials.

Sealing ability of three different materials to repair furcation perforations using computerized fluid filtration method

Background. The present study aimed to evaluate the sealing ability of three different calcium silicate-based materials in furcation perforations. Methods. Seventy-six human mandibular molar teeth were selected. Perforations were created in the center of the pulp chamber floor. The experimental teeth were randomly divided into three groups (n=22). Perforations were repaired with MTA Angelus, Endocem MTA, or EndoSequence BioCeramic Root Repair Material Fast Set Putty (BC-RRM Putty). Microleakage of the different repair materials to be tested was measured by computerized fluid filtration method at 24- and 72-hour intervals. Results. For each time interval, no statistically significant difference was observed between the groups. For Endocem MTA and BC-RRM Putty groups, the difference between the leakage values measured at both periods was not statistically significant (P>0.05). However, there was a significant difference for the MTA Angelus group (P<0.05). Conclusion. All the calcium silicate-based materials used in the present study showed similar performance in repairing furcation perforations at 24- and 72-hour intervals.