Fluoride release and absorption at different pH from glass-ionomer cements.

OBJECTIVE: The aim of this study was to evaluate the fluoride release (release-tests) from two glass-ionomer cements (GIC), before and after NaF solution treatment (fluoride treatment) in different pH environments. MATERIALS AND METHODS: After 21 days, every second sample was submitted to fluoride treatment to simulate a fluoride recharge. After fluoride treatment every second sample was submitted to a further three days of long release-tests. Sample surfaces were analyzed by SEM before and after the release-tests in all pH solutions studied. RESULTS: The present study showed that GICs released fluoride ions for the duration of the examination period. For both materials the amount of F(-) released at low pH was considerably greater than at higher pH. The massive superficial breaking up observed by SEM probably promoted the releasing processes. Recharge is possible at different pH levels using NaF solution. CONCLUSIONS: Fluoride release may depend on GICs surface degradation caused by pH in the solution. The use of this kind of material may be an important issue in patients with with low pH saliva and with a high risks caries.

In vivo fluid movement through dentin adhesives in endodontically treated teeth.

Fluid transudation through simplified dentin adhesives can occur in bonded vital crown dentin, since these adhesives behave as permeable membranes after polymerization. The effect of adhesive permeability in endodontically treated teeth is unknown. This study examined the hypothesis that in vivo fluid movement through simplified adhesives occurs when they are applied to root canals. Dowel spaces were prepared in endodontically treated teeth with single root canals. Six adhesives were applied to the intra-radicular dentin of canal walls. Impressions were obtained with polyvinyl siloxane, and replicas were fabricated with the use of polyether impression material. Replica hemisections were gold-coated for SEM examination. Fluid transudation was evident on the adhesive surfaces of all simplified total-etch and self-etch adhesives. Conversely, most of the specimens bonded with the control three-step total-etch adhesive were devoid of fluid droplets. Permeability of simplified adhesives results in water movement, even in root-treated dentin. This may adversely affect the coupling of auto-/dual-cured resin cements.

Büschke-Lowenstein tumour in pregnancy.

During pregnancy a localised human papillomavirus (HPV) lesion may, in rare cases, develop into a Büschke-Lowenstein tumour. The choice of treatment is crucial as standard systemic treatment is teratogenic. We performed laser CO2 microsurgery because it has a low incidence of complications.

[Salivary glands swelling after the administration of a non-ionic iodized contrast medium]. / Tumefazione delle ghiandole sottomascellari dopo somministrazione di mezzo di contrasto iodato non ionico.

Salivary gland tumefaction (iodide mumps) is a rare, but possible, reaction to endovenous administration of a contrast medium. The authors describe three cases of bilateral, iodide mumps where swelling of the submaxillary salivary glands was seen after administration of a non ionic iodized contrast medium for upper GI examination. The cases differ from what is reported in the literature in that they occurred in subjects with good renal function and who had not previously presented any other early or delayed side effects subsequent to the use of a contrast medium. The authors then discuss the pathogenic hypotheses for this disorder subsequent to the administration of the new generation, low osmolarity contrast media which are generally better tolerated than traditional media.

Phonetic rehabilitation after laryngectomy.

This work deals with the phonetic rehabilitation of patients after laryngectomy, describing the various types of alaryngeal voice. The rehabilitation was monitored with a computer by means of a specific voice programme which permits the registration, visualization and reproduction of each sound emitted in conjunction with the classification of the principal parameters, thus allowing the patient to check his acoustic feedback.

[Renin and aldosterone]. / Renina e aldosterone

The radioimmunological dosages of renin and of aldosterone are used nowadays in clinical practice for research purposes only. The measurement of activity of plasma renin may be considered a significant indication of the concentration of the enzime in plasma and, indirectly, of its secretion. Several factors take a part in the regulation of renin secretion (mean arterial pressure, introduction of sodium and potassium, the sympathetic nervous system, ADH and concentration of angiotensin II in plasma). In pathological conditions such factors may cause alteration of the renin-angiotensin II system, thus determining hyperreninisms and hyporeninisms, whether associated with arterial hypertension or not. Several factors take a part on aldosterone secretion too (ACTH, sodiaemia, potassiaemia, renin-angiotensin II system). In pathological conditions the alteration of the regulation system may lead to hyperaldosteronism or to hypoaldosteronism of primary or secondary type. A survey of recent research on the physiopathology of the renin-aldosterone system is also given.