Fibrin adhesive implant in wound healing repair of dental sockets with topical application of epsilon aminocaproic acid: Histological analysis

The aim of the study was to evaluate wound healing repair of dental sockets after topical application of 5% epsilon-aminocaproic acid (EACA) and the use of fibrin adhesive implant in rats under anticoagulant therapy with warfarin. Sixty Albinus wistar rats were used, divided into three groups of 20. In Group I, the animals were given 0.1 mL/100 mg of 0.9% saline solution per day, beginning 6 days before dental extraction and continuing throughout the experimental period. In Group II, the animals received 0.03 mL of sodium warfarin daily, beginning 6 days before the surgery and continuing until the day of sacrifice; after tooth extractions, the sockets were filled with fibrin adhesive material. In Group III the animals were treated as in Group II, and after extractions, the sockets were irrigated with 5 mL of 5% EACA and filled with the same fibrin adhesive material. All groups presented biological phases of wound healing repair, the differences being evident only in the chronology. The results obtained in Group III were very similar to those of Group I in the last period of wound repair, whereas Group II presented a late chronology compared to the other groups. © 2005 Wiley Periodicals, Inc.

Response of human dental pulp to dentin adhesive systems

Many in vivo studies have stated that the response of the dentin/pulp complex does not depend on the dental material used as the liner or pulp-capping agent. However, several in vitro studies have reported the metabolic cytotoxic effects of resin components applied to fibroblast and odontoblast cell lines. The aim of this study was to evaluate the human pulp response following direct pulp capping with current bonding agents and calcium hydroxide (CH). Sound premolars scheduled for orthodontic extraction had their pulp tissue mechanically exposed. After hemorrhage control and total acid conditioning, the experimental bonding agents, including All Bond 2, Scotchbond MP-Plus, Clearfil Liner Bond 2, and Prime & Bond 2.1 were applied on the pulp exposure site. CH saline paste was used as the control pulp-capping agent. All cavities were restored with Z-100 resin composite according to the manufacturer's instructions. Following extractions, the teeth were processed for microscopic evaluation. In the short term, the bonding agents elicited a moderate inflammatory pulp response with associated dilated and congested blood vessels adjacent to the pulp exposure site. A mild inflammatory pulp response was observed when Clearfil Liner Bond 2 or CH was applied on the pulp exposures. With time, macrophages and giant cells engulfing globules and components of all experimental bonding agents displaced into the pulp space were seen. This chronic inflammatory response did not allow complete pulp repair, which interfered with the dentin bridge formation. Pulp exposures capped with CH exhibited an initial organization of elongated pulp cells underneath the coagulation necrosis. CH stimulated early pulp repair and dentin bridging that extended into the longest period. The bonding agents evaluated in the present study cannot be recommended for pulp therapy on sound human teeth.

Testicular biopsy with Tru-Cut needle in conjunction with fibrin adhesive or nylon suture: assessment of post-biopsy testicular function in rams

Testicular biopsy has been a complementary technique for clinical and research purposes to evaluate reproductive function in males. However, hemorrhage, inflammation, degeneration, and adhesion are factors that might limit the use of this procedure. In order to minimize these potential problems, fibrin glue derived from snake venom, a tissue adhesive with sealing, hemostatic, and healing properties, was used in conjunction with bilateral testicular biopsy with the Tru-Cut needle and was compared with a more conventional technique that uses nylon suture. Thirty mature rams were randomly assigned to three groups of 10 animals each, as follows: nonsurgical control group (no scrotal surgery, or biopsy); biopsy + glue group (fibrin glue on puncture sites and skin incisions) and biopsy + suture group (compression with swab on puncture sites and suturing of skin incision). The surgeries of the rams in the biopsy groups were performed on the same day, which was designated Day 0 for all three groups. Data of scrotal circumference, number of spermatozoa per ejaculum, percentage of morphologically abnormal spermatozoa, spermatozoa motility, and serum testosterone concentrations from Days -7, 20, 40, 60, 80 and 100 were evaluated. There were no significant differences between groups within days for any of the parameters evaluated. In conclusion, the testicular biopsy procedure using the Tru-Cut needle in conjunction with conventional nylon suture or the more novel fibrin glue in rams did not affect any of the parameters of testicular function evaluated in this study and was shown to be relatively simple, safe and efficient. (C) 2002 Published by Elsevier B.V. B.V.

Adhesive Quality of Self-adhesive and Conventional Adhesive Resin Cement to Y-TZP Ceramic Before and After Aging Conditions

Purpose: This study evaluated the adhesive quality of simplified self-adhesive and conventional resin cements to Y-TZP in dry and aged conditions. Methods: Y-TZP ceramic blocks (N=192) (5 x 5 x 2 mm) were embedded in acrylic resin and randomly divided into two groups, based on surface conditioning: 96% isopropanol or chairside tribochemical silica coating and silanization. Conditioned ceramics were divided into four groups to receive the resin cements (Panavia F 2.0, Variolink II, RelyX U100 and Maxcem). After 24 hours, half of the specimens (n=12) from each group were submitted to shear bond strength testing (0.5 nun/minute). The remaining specimens were tested after 90 days of water storage at 37 degrees C and thermocycling (12,000x, 5 degrees C-55 degrees C). Failure types were then assessed. The data were analyzed using three-way ANOVA and the Tukey's test (alpha=0.05). Results: Significant effects of ceramic conditioning, cement type and storage conditions were observed (p<0.0001). The groups cleaned using alcohol only showed low bond strength values in dry conditions and the bond strength was reduced dramatically after aging. Groups conditioned using silica coating and silanization showed higher bond strengths both in dry and aged conditions. A high number of specimens failed prematurely prior to testing when they were cleaned using 96% isopropanol. Conclusion: Overall, silica coating and silanization showed higher, stable bond strengths with and without aging. The durability of resin-ceramic adhesion varied, depending on the adhesive cement type.

Osseous regeneration in the presence of fibrin adhesive material (Tissucol) and epsilon-aminocaproic acid (EACA).

The effects of Tissucol and Tissucol/EACA on bone healing were evaluated histologically. Experimental defects were made in both tibias of 25 rats. Test materials were placed in defects in right tibias and left tibias served as control. Five animals in each group were killed at 1, 3, 7, 14 and 21 days after surgery. Results showed that: a) Tissucol did not interfere with connective and osseous tissue formation; b) Tissucol allowed new bone formation; c) Tissue residues in Tissucol groups in sections of 21-day specimens did not impair healing; d) Tissucol/EACA was usually completely resorbed and healing was complete 21 days after surgery in the Tissucol/EACA group.

Effects of fibrin adhesive material (Tissucol) on alveolar healing in rats under stress.

The effects of Tissucol on alveolar healing following stress were evaluated histologically, comparing three groups of 28 male albino rats each. Stress was applied and their right upper incisors were extracted. Group A served as an empty control site. In Group B, Tissucol was applied into the alveolar cavity. Group C received local antifibrinolytic treatment (alveolar irrigation with epsilon-aminocaproic acid solution) before implant of Tissucol into the tooth socket. Four animals in each group were killed at 1, 3, 6, 9, 15, 21 and 24 days after surgery. Results showed that: 1) Tissucol did not interfere with connective and osseous tissue formation; 2) Tissucol allowed new bone formation; 3) Tissucol residues in Group B in sections of 24-day specimens did not impair healing; 4) Tissucol was usually completely resorbed and healing was complete 24 days after surgery in Group C.

Biocompatibility of an adhesive system applied to exposed human dental pulp

Human pulp tissue was directly capped with All Bond 2, or calcium hydroxide and evaluated 7, 30, or 60 days after the procedures. Histological analysis was performed to assess the inflammatory cell response, tissue disorganization, dentin bridging, and the presence of bacteria. At 7 days, with All Bond 2 capping, there was a large area of neutrophilic infiltrate underlying the pulp capping material, and the death of adjacent odontoblasts, was observed. However, with time, the neutrophilic reaction was replaced by fibroblastic proliferation with macrophages and giant cells surrounding globules of resin scattered in the coronal pulp tissue. The persistent inflammatory reaction and hyaline alteration of extracellular matrix inhibited complete pulp repair or dentin bridging. In contrast, at 7 days, the pulp tissue capped with calcium hydroxide exhibited odontoblast-like cells organized underneath coagulation necrosis. Pulp repair evolved into apparent complete dentin bridge formation at 60 days. All Bond 2 did not appear to allow any pulp repair and does not appear to be indicated for direct pulp capping of human teeth. Copyright © 1999 by The American Association of Endodontists.

Cytotoxic effects of current dental adhesive systems on immortalized odontoblast cell line MDPC-23

Objectives: Evaluate the cytotoxic effect of the three dental adhesive systems. Methods: The immortalized mouse odontoblast cell line (MDPC-23) was plated (30,000 cell/cm 2) in 24 well dishes, allowed to grow for 72 h, and counted under inverted light microscopy. Uncured fresh adhesives were added to culture medium to simulate effects of unset adhesive. Three adhesives systems were applied for 120 min to cells in six wells for each group: Group 1) Single Bond (3M), Group 2) Prime & Bond 2.1 (Dentsply), and Group 3) Syntac Sprint (Vivadent). In the control group, PBS was added to fresh medium. The cell number was counted again and the cell morphology was assessed under SEM. In addition, the adhesive systems were applied to circles of filter paper, light-cured for 20 s, and placed in the bottom of 24 wells (six wells for each experimental materials and control group). MDPC-23 cells were plated (30,000 cell/cm 2) in the wells and allowed to incubate for 72 h. The zone of inhibition around the filter papers was measured under inverted light microscopy; cell morphology was evaluated under SEM; and the MTT assay was performed for mitochondrial respiration. Results: The fresh adhesives exhibited more toxic (cytopathic effects) to MDPC-23 cells than polymerized adhesives on filter papers, and as compared to the control group. The cytopathic effect of the adhesive systems occurred in the inhibition zone around the filter papers, which was confirmed by the MTT assay and statistical analysis (ANOVA) combined with Fisher's PLSD test. In the control group, MDPC-23 cells were dense on the plastic substrate and were in contact with the filter paper. In the experimental groups, when acid in the adhesive systems was removed by changing the culture medium, or when the adhesives were light-cured, some cells grew in the wells in spite of the persistent cytotoxic effect. Significance: All dentin adhesive systems were cytotoxic odontoblast-like cells. Both acidity and non-acidic components of these systems were responsible for the high cytopathic effect of those dental materials. © 1999 Academy of Dental Materials. Published by Elsevier Science Ltd. All rights reserved.

Use of one-bottle adhesive as an intermediate bonding layer to reduce sealant microleakage on saliva-contaminated enamel

Purpose: To evaluate the influence of three different adhesives, each used as an intermediary layer, on microleakage of sealants applied under condition of salivary contamination. Materials and Methods: Six different experimental conditions were compared, 3 with adhesives and 3 without. After prophylaxis and acid etching of enamel, salivary contamination was placed for 10 s. In Group SC the sealant was applied after saliva without bonding agent and then light-cured. In Group SCA, after saliva, the surface was air dried, and then the sealant was applied and cured. In Groups ScB, SB and PB, a bonding agent (Scotchbond Dual Cure/3M, Single Bond/3M and Prime & Bond 2.1/Dentsply, respectively) was applied after the saliva and prior to the sealant application and curing. After storage in distilled water at 37°C for 24 hrs, the teeth were submitted to 500 thermal cycles (5°C and 55°C), and silver nitrate was used as a leakage tracer. Leakage data were collected on cross sections as percentage of total enamel-sealant interface length. Representative samples were evaluated under SEM. Results: Sealants placed on contaminated enamel with no bonding agent showed extensive microleakage (94.27% in SC; 42.65% in SCA). The SEM revealed gaps as wide as 20 μm in areas where silver nitrate leakage could be visualized. In contrast, all bonding agent groups showed leakage less than 6.9%. Placement of sealant with a dentin-bonding agent on contaminated enamel significantly reduced microleakage (P< 0.0001). The use of a bonding agent as an intermediary layer between enamel and sealant significantly reduced saliva's effect on sealant microleakage.