In vitro performance of ultrasound enamel preparation compared with classical bur preparation on pit and fissure sealing.

AIM: Fissure sealants are effective in preventing caries. The aim of this in vitro study was to evaluate the effects of two different enamel surface preparation techniques for pit and fissure sealing. MATERIALS AND METHODS: Sixty extracted sound third molars were used. For each tooth, the mesial half of the occlusal fissures was treated with ultrasound diamond tip T1 mounted on an ultrasonic handpiece, while the distal half with conventional diamond bur. The teeth were randomly divided into 2 groups (n = 30/each). Group 1 samples were stored in distilled water at 4 °C. For group 2 samples, sealing of occlusal fissures was performed according to standard procedures. Bucco-lingual cuts parallel to the long axis of the tooth were made in order to separate the two different types of preparations. The effects of the executed procedures were assessed with SEM. RESULTS: Surfaces prepared with ultrasound system showed the presence of residual debris and appeared more irregular than surfaces prepared with traditional bur system. Furthermore, images showed the presence of cracks on the bottom and on the walls of the ultrasound prepared fissures. CONCLUSION: Conventional bur surface treatment showed a better performance when compared to ultrasound preparation and could probably ensure superior sealant retention.

A successful two-step integrated protocol of anti-HBV vaccination in chronic uremia.

A prospective study was performed in 40 chronic uremics which included: (1) the intramuscular administration to all patients of 40 micrograms of a DNA-recombinant vaccine (Engerix-B) at 0, 1, 2, 6 months; (2) an intramuscular booster dose of 40 micrograms at 18 months in patients having an anti-HBs titer greater than 100 mIU/ml at the 7th month (group A); (3) a further intramuscular supplementary dose of 40 micrograms at 12 months (besides that at 18 months) in patients developing an antibody titer less than 100 mIU/ml at the 7th months (group B); (4) an intradermal course of 5 micrograms of vaccine every 2 weeks until the protective titer (greater than or equal to 10 mIU/ml) was achieved, and then every month for a total of 6 months in patients who did not develop a protective titer even after 19 months (group C). At the end of the study, all patients had developed a protective titer: 77.5% after the 4th intramuscular dose, 12.5% after the 5th and 10% after 3.5 +/- 0.5 (mean +/- SEM) intradermal inoculations. The mean antibody titers were 1,461 +/- 98 mIU/ml in group A, 594 +/- 684 in group B and 131 +/- 133 in group C. In conclusion, our two-step integrated protocol gives an anti-HBs protective titer in all our patients.

Hepatitis B virus infection in chronic uremia: long-term follow-up of a two-step integrated protocol of vaccination.

Active immunization is crucial for eradicating hepatitis B virus infection from dialysis units. A prospective study was performed in 63 consecutive chronic uremic patients, which included the following: (1) the intramuscular (IM) administration of 40 micrograms of a DNA-recombinant vaccine (Engerix-B, Smith Kline & French Laboratories, Milan, Italy) to all chronic uremic patients at 0, 1, 2, and 6 months; (2) the antibody titer determination at the seventh month (chronic uremic patients with a titer > 100 mIU/mL received an IM booster dose of 40 micrograms at 18 months [group A], and those with a titer < 100 mIU/mL received a further IM dose of 40 micrograms at 12 months [group B]); and (3) the intradermal inoculation of 5 micrograms of vaccine every 2 weeks until the protective titer (> or = 10 mIU/mL) was achieved, and then monthly for 6 months, in chronic uremic patients who did not have a protective titer even after 19 months (group C). Thus, 41, 17, and five chronic uremic patients were allocated to groups A, B, and C, respectively. All developed a protective titer: 79.4%, 84.0%, and 87.5% after the fourth, fifth, and sixth IM dose at 7, 13, and 19 months, respectively. Five chronic uremic patients (group C) achieved seroprotection after 3.8 +/- 0.5 (SEM) intradermal inoculations.(ABSTRACT TRUNCATED AT 250 WORDS)