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Objective: The aim of this investigation was to evaluate the effect different cleaning techniques used on enamel surfaces have on the bond strength of a composite resin to the dental enamel. Method and Materials: Eighty-eight bovine enamel fragments were mounted in acrylic resin bases. The enamel surfaces were sanded using 200-, 400-, and 600-grit sandpapers, thus creating a smear layer. These surfaces were then randomly divided in 2 groups: 1 of them received salivary contact for 10 minutes, and the other received it for 60 minutes. Then all surfaces were cleaned with a pumice and water paste applied with a rubber cup, followed by the application of biological detergent, sodium bicarbonate jet, or air/water spray. After cleansing, the enamel surfaces received the application of the Scotchbond Multi-Purpose adhesive system and Z100 composite resin, following the manufacturer's instructions, using an appropriate matrix. After storage at 37°C for 8 days, traction tests were carried out using an Instron machine operating at 0.5 mm/minute. Some fractured specimens (randomly chosen) were analyzed under scanning electron microscopy. Results: The statistical analysis using descriptive and inferential methods did not show significant differences between the different periods of time of salivary contact. The technique of pumice and water paste cleaning followed by the application of biological detergent was significantly more efficient than the others. Scanning electron micrographs of the fragments after traction tests confirmed these results. Conclusion: The technique of pumice and water paste cleaning followed by the application of biological detergent was the treatment that allowed the best results in terms of resin bonding to bovine enamel covered with acquired pellicle, and the sodium bicarbonate jet technique presented the lowest bond strength values and seemed to disturb the acid conditioning of enamel surfaces. [ABSTRACT FROM AUTHOR]

Interaction between resin tags and microtags of adhesive systems and dentinal collagen fibrils is a poorly understood aspect of adhesion. This study evaluated this interaction in 25 recently extracted human third molars. Each tooth was embedded in an epoxy resin and cross-sectioned to obtain two 1-mm-thick dentin disks. The outer dentin surfaces were polished with wet 600-grit sandpaper to create a uniform smear layer. After etching with 35% phosphoric acid for 15 seconds, the primer and adhesive of Scotchbond Multi-Purpose and the resin composite Z100 (3M Dental Products, St Paul, MN 55144, USA) were placed on the dentinal surfaces according to the manufacturer's instructions. The disks were left in distilled water at 37°C for two weeks, then fractured perpendicular to the bonded surfaces in order to obtain two hemi-disks. The fractured surfaces were treated with 2N-chloridric acid and processed for scanning electron microscopy. Gold-coated specimens were examined with a JEOL 6100 scanning electron microscope. Results showed a hybrid layer with resin tags of approximately 100 µm in length and numerous and fine branching resin microtags. The tags and microtags created by this three-step adhesive system were observed in intimate contact with the collagen fibrils of dentin, even in deeper zones which were not affected by acid etching. It suggests that adhesion to dentin may include both micromechanical and chemical aspects. [ABSTRACT FROM AUTHOR]

The aim of this research was to analyse the long-term clinical behaviour of two dental materials applied as filling under silver amalgam restorations: glass–ionomer cement (GIC) and composite resin with adhesive system (CR). In this study, 117 posterior teeth (29 premolars and 88 molars) were selected with carious lesions which resulted in great loss of dentin and cusps with unsupported enamel. After caries removal, cavities were prepared and totally filled with GIC or with CR. In a following visit, new cavities were prepared, leaving the employed filling material as a base and support for the enamel, which were then restored with silver amalgam. Restorations were evaluated periodically after 6 months and up to 5 years. Both fracture and pulpal involvement rates were low. Although differences could be observed in the behaviour of the materials, statistical survival estimation showed that the performances of GIC and CR as filling material were similar. There was a significant association both between kind of tooth (molar or premolar) and long-term survival of the restorations; and between degree of unsupported enamel and the same long-term survival. Our results confirmed that the technique in which GIC or CR are used as filling under silver amalgam restorations is clinically acceptable. [ABSTRACT FROM AUTHOR]

Vasography may cause stricture of the vas deferens. The probable causes of this obstruction are traumatic lesion at the puncture site and the radiological contrast material used. Because of this problem we performed an experimental study using Wistar rats, which were divided into four groups: Group A-Control, Group B-injection of a saline solution, Group C-hypaque injection, Group D-hypaque plus saline solution. According to the results obtained it was concluded that the needle puncture is not responsible for stricture of the vas deferens. Hypaque is responsible for 5% of strictures and the use of a saline solution to wash the vas did not show any benefit. [ABSTRACT FROM AUTHOR]

A total of 205 patients have undergone stone extraction surgery. Three groups were studied: in 70 patients the stones were removed by flank incision, in 20 patients by posterior incision and 80 patients were treated by percutaneous nephrolithotomy. Patients submitted to percutaneous nephrolithotomy had a shorter hospitalization, operative time and a significantly reduced period of recuperation, allowing earlier return to work and decreased disability. Narcotic drugs were demanded in a lower amount in the percutaneous nephrolithotomy group. [ABSTRACT FROM AUTHOR]

Thirty-one patients with urethral stricture were subjected to internal urethrotomy under visual control. The patients were divided into two groups according to the surgical procedure: electrosurgical or cold resection. A modification of the Sachse knife was introduced in order to permit its use with the American Cystoscope Makers Inc. instruments. The success rate with cold resection was 81.81% and with the electrosurgical procedure 40%. Internal urethrotomy with cold resection is a simple and harmless operation, being a first choice in the treatment of urethral stricture. [ABSTRACT FROM AUTHOR]

Treatment of penile fracture, due to the low number of cases, still lacks adequate documentation. The authors present two cases of such pathology, which were treated conservatively, and presented penile deformities in the late follow up. Both conservative and surgical management are discussed; since surgery in these cases has low mortality and clinical treatment can be followed by various sequelae, the authors favour the former, stressing that it is mandatory in cases with urinary obstruction, progressive infiltration or cutaneous laceration. [ABSTRACT FROM AUTHOR]

Seven cases of anterior urethral stricture were studied. The diagnosis was made by exclusion of the inflammatory and traumatic causes. In three cases the stricture was located in the bulbar and in four cases in the penile urethra. The results obtained were good, with a follow-up of 5 to 50 months. Considerations are made about embryogenic, diagnostic, clinical picture and treatment. The verification of extensive lesions of the urethra determined the use of more complex surgical techniques of Johansen's urethroplasty devised for the treatment of this kind of pathology. [ABSTRACT FROM AUTHOR]

A case of menouria (Youssef's syndrome) following a vesicovaginal fistula repair is presented. The patient had typical clinical features of cyclic hematuria, absence of vaginal bleeding and complete urinary continence. Diagnosis was established by cystoscopy, cystography and hysterosalpingography which disclosed the communication between the bladder and the uterine cavity. Surgical treatment was hysterectomy with the closure of the bladder opening. The authors quote similar cases reported in the literature and attention is also called to the fact that the first case of menouria was reported in the literature by Machado in 1935. [ABSTRACT FROM AUTHOR]

For assessing plasma and tissue concentrations of norfloxacin after oral administration, twelve patients with benign prostatic hypertrophy (BPH) were given two doses of 400 mg norfloxacin approximately 12 hours apart prior to transurethral resection of the prostate (TURP). Prostatic tissue samples and blood samples were collected and assayed for norfloxacin content by HPLC. The mean peak norfloxacin concentration in plasma was 1.63 μg/ml (range 0.63 to 3.38 μg/ml). The mean peak concentration in prostatic tissue was 1.63 μg/g (range 0.75 to 3.30 μg/g). The plasma and prostatic tissue levels of norfloxacin exceeded the MIC's of most urinary tract pathogens. The data suggest that norfloxacin may be useful in the treatment of chronic bacterial prostatitis. [ABSTRACT FROM AUTHOR]