Effect of substrate age and adhesive composition on dentin bonding.

PURPOSE: To study the effect of dentin age and adhesive composition on the microtensile dentin bond strengths (µTBS) of five dentin adhesives. MATERIALS AND METHODS: Sixty extracted caries-free human teeth were assigned to the appropriate age group: less than 21 years of age (<21), 21-40 years of age (21-40), and greater than 40 years of age (>40). For each age group, specimens were randomly divided into five dentin adhesives: (1) Adper Easy Bond (EB, 3M ESPE), a one-step self-etch adhesive; (2) Experimental Adper Easy Bond without the Vitrebond Co-polymer (CP) (EBnoCP, 3M ESPE); (3) Adper Single Bond Plus (SB, 3M ESPE), a two-step etch&rinse adhesive; (4) Experimental Adper Single Bond Plus without CP (SBnoCP, 3M ESPE); and (5) Adper Scotchbond Multi-Purpose (MP, 3M ESPE), a three-step etch&rinse adhesive, as the control group. Specimens were sectioned in X and Y directions and the resulting beams were tested to failure in tension mode at a crosshead speed of 1 mm/min. Statistical analysis was computed using t-test and two-way analysis of variance followed by Fisher least significant difference multiple comparison post hoc test at p < 0.05. RESULTS: The highest mean µTBS values were obtained in the control group (MP) for all age groups. EB resulted in statistically similar mean µTBS compared to EBnoCP for all age groups: p = 0.538 for (<21); p = 0.974 for (21-40); and p = 0.909 for (>40). SB resulted in statistically higher mean µTBS than SBnoCP for all age groups [p<0.009 for (<21); p<0.028 for (21-40); and p<0.041 for (>40)]. MP, the control group, resulted in statistically lower mean µTBS when applied to the oldest age group (>40) compared to the youngest age group (<21), at p < 0.04. When means were pooled for the variable 'age group,' SB resulted in significantly higher mean µTBS than SBnoCP at p < 0.009, while EB resulted in statistically similar mean µTBS compared to EBnoCP (p=0.9). MP resulted in statistically higher mean µTBS than all other adhesives-SB (p<0.0001), SBnoCP (p<0.0001), EBnoCP (p<0.022), and EB (p<0.046). CONCLUSIONS: The substrate age influenced the bonding ability of the three-step etch&rinse adhesive. The presence of a carboxylic-based polymer (CP) enhanced the bonding ability of the two-step etch&rinse adhesive.

Laboratory bonding ability of a multi-purpose dentin adhesive.

PURPOSE: To evaluate the laboratory dentin and enamel microtensile bond strengths (microTBS) and interfacial ultra-morphology of a new multi-purpose dental adhesive applied under different bonding strategies. METHODS: microTBS - 36 extracted caries-free human molars were assigned to six groups: Group CSE - Clearfil SE Bond, a 2-step self-etch adhesive (self-etch control); Group SBU-SE - Scotchbond Universal Adhesive (SBU), applied as a one-step self-etch adhesive; Group OSLm - OptiBond SOLO Plus (OSL), a 2-step etch-and-rinse adhesive applied on moist dentin (etch-and-rinse control); Group OSLd - OSL applied on air-dried dentin; Group SBU-ERm - SBU applied as a 2-step etch-and-rinse adhesive on moist dentin; Group SBU-ERd - SBU applied as a 2-step etch-and-rinse adhesive on air-dried dentin. Build-ups were constructed with Filtek Z250 and cured in three increments of 2 mm each. Specimens were sectioned with a slow-speed diamond saw under water in X and Y directions to obtain bonded beams that were tested to failure in tension at a crosshead speed of 1 mm/minute. Statistical analyses were computed using one-way ANOVA followed by post-hoc tests at P< 0.05. Ultra-morphologic evaluation - dentin-resin interfaces were prepared for each of the six groups, processed, and observed under a FESEM. RESULTS: microTBS - OSLm resulted in significantly higher mean microTBS (63.0 MPa) than the other five groups. All SBU groups ranked in the same statistical subset regardless of the dentin treatment. The lowest mean microTBS were obtained with CSE (47.2 MPa) and OSLd (50.2 MPa), which were ranked in the same statistical subset. Ultramorphologic evaluation - The two self-etch adhesives resulted in a similar ultra-morphology. Dried dentin did not preclude the formation of a hybrid layer with SBU-ERd, as opposed to OSLd.

Evaluation of an epidemic of sporotrichosis in cats: 347 cases (1998-2001).

OBJECTIVE: To evaluate characteristics of a large epidemic of sporotrichosis in cats. DESIGN: Retrospective study. ANIMALS: 347 cats with naturally acquired infection with Sporothrix schenckii. PROCEDURE: Medical records were reviewed for data regarding clinical, mycologic, histopathologic, and routine hematologic and serum biochemical findings; assays for FIV-specific antibodies and FeLV antigen; antifungal treatment; and follow-up. RESULTS: Lesions varied from small papules to extensive zones of necrosis. Ten cats had no skin lesions, 114 had skin lesions at a single site, 86 had skin lesions in 2 sites, and 137 had skin lesions in 3 or more sites. Respiratory tract signs were observed in 154 cats and were the most frequent extracutaneous sign. Anemia, leukocytosis with neutrophilia, hypoalbuminemia, and hyperglobulinemia were the main blood abnormalities. Antibodies against FIV were detected in 28 cats, FeLV antigen was detected in 2 cats, and both were detected in 1 cat among 142 cats tested. During the study, 118 cats were lost to follow-up and 124 died. Of 266 cats that were treated, 68 were cured. Complete healing of the lesions was observed regardless of the presence of extracutaneous signs, general condition, treatment schedule, or coinfection with FIV. CONCLUSIONS AND CLINICAL RELEVANCE: Feline sporotrichosis was evident in subclinical to severe forms; however, cats can respond well to regular and prolonged antifungal treatment.