In vitro buffering properties of 3 composite resins.

AIM: A dental composite resin, Ariston pHc, has been described as having a cariostatic effect by buffering acid saliva and preventing decalcification and infiltration of restorations. The buffering effect has been reported due to the release of OH- originated from the alkaline glass embedded in the resin. The release would occur only in the presence of low salivary pH values. The aim of this in vitro investigation was to evaluate pH variations induced by Ariston pHc and 2 other composite resins (P60 and Z100). METHODS: Eighteen samples were prepared for each composite and 5 specimens of each brand were embedded in artificial saliva according to Brugirar and Mazille, at 3 different pH values. A 1(st) group of 5 specimens of each tested resin was immersed in neutral artificial saliva at pH 7.7, a 2(nd) group in acidified artificial saliva at pH 5.45 and a 3(rd) group in alkalised saliva at pH 9.25. Three other samples of each resin were immersed in tubes containing distilled water at pH 7.23 and served as controls. Twelve tubes were filled only with neutral, alkalised and acidified artificial saliva and distilled water at the above mentioned pH values. Measurements of pH modifications were taken after 1, 3, 9, 14, 31 days. RESULTS. Ariston pHc raised the pH of distilled water up to 9.59 after 1 day, and to 8.42 after 31 days. This pH modification shown by Ariston pHc in distilled water, compared to those of the other 2 composites were statistically highly significant, with p<0.001, while the pH variations of saliva containing the 3 resins were negligible, except for acidified saliva with Ariston pHc, where a slight pH enhancement with some statistical significance (p=0.04) was found. However, acidified saliva without any resin embedded was found to shift to neutrality as well. CONCLUSION: These results strongly suggest that none of the 3 tested materials can achieve an effective buffering action in vitro on low salivary pH values. However, the ability of Ariston pHc to raise the pH in distilled water, and to a lesser degree in acidified saliva, suggests that an in vivo buffering effect cannot be excluded.

[Can one use probabilistic protocols for antibiotic therapy in intensive care units?]. / Peut-on utiliser des protocoles d'antibiothérapie probabiliste en réanimation?

Due to a large spectrum, empiric antibiotics treatments participate to the increase in bacterial resistance. In order to improve its indications, the implementation of therapeutic guidelines in an ICU was studied. Empiric therapy was administered in 30% of the 178 patients receiving antimicrobial agents. Large spectrum drugs were prescribed in 26% of empiric treatments. The mean duration of empiric antibiotics administration was 3.2 days. It was concluded that it was possible to use guidelines of empiric antibiotic in an intensive care unit.

[Osteoplastic tooth transposition. Surgical method for orthognathic placement of a single tooth]. / Die osteoplastische Zahntransposition. Eine chirurgische Methode zur orthograden Einstellung von Einzelzähnen.

The procedure described in this article is based on the surgical subtotal luxation of a tooth-containing alveolar segment and allows the repositioning of single teeth while almost regularly safeguarding tooth vitality. This procedure has proven particularly effective in the treatment of maxillary anteriors, canines and premolars. For patients preferring surgical correction to long-term orthodontic treatment this limited operative intervention allows safe orthodontic alignment. To date, relapses have not been observed in the cases treated. Stable immobilization of up to six weeks postoperatively is achieved by splinting.

[Local and systemic antimycotic therapy of Candida-induced denture stomatitis]. / Lokale und systemische antimykotische Therapie der Candida-Prothesenstomatitis.

15 patients with clinically outstanding prosthesis stomatitis due to microscopically proved candida infection underwent treatment with the antimycotic agent Clotrimazol. After two weeks' therapy improvement was observed in 6 patients (40%), healing in 4 patients (27%); 4 patients did not respond and in one patient the condition was temporally made worse. Examination two weeks after cessation of therapy showed that the clinical condition in 8 patients was as bad as before therapy (53%), and 4 patients (27%) were symptom-free. 3 patients (20%) had improved further. Suggestions for the treatment of prosthesis stomatitis can be derived from these findings.