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Until recently, little was known about the susceptibility pattern of Cyberlindnera fabianii (Cy. fabianii) planktonic cells and biofilms regarding the most frequently administered systemic antifungals, despite the high mortality rate and its potential role in catheter-related infections. In the current study, the activity of fluconazole, amphotericin B and echinocandins (anidulafungin, caspofungin and micafungin) was determined against planktonic and sessile cells of Cy. fabianii clinical isolates (n = 8). Planktonic minimum inhibitory concentrations (MICs) ranged from 1 to 2, from 0.25 to 1, from 0.015 to 0.06, from 0.03 to 0.12 and from 0.25 to 0.5 mg/l for fluconazole, amphotericin B, anidulafungin, caspofungin and micafungin, respectively. One-day-old biofilms were highly resistant to fluconazole (MIC ranged from 512 to > 512) compared to planktonic counterparts, but not to amphotericin B (MIC ranged from 0.25 to 2 mg/l) and echinocandins (MIC ranged from 0.06 to 2 mg/l). Based on the calculated planktonic killing rates, the highest activity was observed in the case of anidulafungin (k values ranged from 0.37 to 2.09), while micafungin, caspofungin, amphotericin B and fluconazole exerted 0.46–1.47, 0.14–0.86, −0.03 to 2.08 and −0.15 to 0.09 killing rate value ranges, respectively. The obtained in vitro planktonic and sessile susceptibility patterns suggest that echinocandins and amphotericin B may be the most reliable treatment option for the treatment of Cy. fabianii infections.

A szerző a debreceni Stomatológiai Klinika történetének fontos időszakát idézi fel a két kiváló professzor irányítása alatt (Szentpétery József és Keszthelyi Gusztáv) az 1979-től 2000-ig terjedő időszakban.

Pefloxacin is a second-generation fluoroquinolone antibiotic. Besides its advantageous characteristics, side effects including the hypofunction of salivary glands, decreased saliva production, and peripheral neuropathy were observed during the administration of pefloxacin. The aim of this study was to investigate the changes in the number of serotonergic immunoreactive fibers and mast cells after pefloxacin treatment in the parotid and sublingual glands of rats to detect the possible neurotoxic effect of pefloxacin. The adult female rats were treated with intraperitoneal (i.p.) injection of pefloxacin for three or seven days (at a concentration of 20 mg/100g body weight) and the serotonergic innervation pattern along with the change in mast cell number were evaluated by using histochemistry and immunohistochemistry in the parotid and sublingual glands. We found that a three-day treatment significantly increased the number of immunoreactive serotonergic nerve fibers, but after a seven-day treatment the number of serotonin positive nerve fibers decreased almost to values of the control group. The alteration of mast cell number was parallel with the changes of the serotonin positive fibers during the treatment. These results suggest that pefloxacin treatment can modify the finely controlled communication between the immune- and the peripheral nervous systems, resulting neurogenic inflammatory process. The background of this process is the altered serotonergic innervation and the increased number of activated mast cells releasing different mediators for example histamine, which can finally lead to reduced number of serotonin positive nerve fibers after a seven-day treatment of pefloxacin leading to atrophy and hypofunction of the salivary glands.

Az elmúlt 30-40 évben a fogászati implantátumok alkalmazása jelentősen megváltoztatta a fogpótlások készítésének lehetőségét.Az első bizonyíték az implantátumokra a maja kultúrából ered (i. sz. 600 körül), Európában az 1500–1800-asévekben többféle módon és különféle anyagok beültetésével próbálkoztak.Magyarországon elsőként 1934-ben Debrecenben helyeztek be csavar implantátumokat alsó állcsontba, melyekreszinte azonnal hídpótlást készítettek. A műtéteket Hüttl Tivadar sebészprofesszor és Karácsonyi Ágoston fogorvos végezték.Számos esetben alkalmazták az eljárást, melyet szabadalmaztatni is kívántak, de egy budapesti vizsgázott fogászfelszólalása miatt 1935. tavaszán a beadványukat visszavonták.Pontosan nem ismerjük a behelyezett implantátumok számát, a sikerességi rátát, azonban tartósságukat jól mutatja,hogy még 1959-ben is találkoztak olyan beteggel, aki még akkor is használta az így elkészült rögzített fogpótlását. Azesetről fényképekkel és röntgenfelvételekkel kiegészített tudományos közlemény született.Cikkünk röviden áttekinti az eljárás menetét, eszközeit és a szabadalmaztatással kapcsolatos ellentmondásokat.

The purpose of this study was to determine whether cherry extract has any effect on salivary α-amylase activity (sAA) or on the level of Streptococcus mutans in human saliva. 70 patients (45 females and 25 males) in three age groups (22 children, 25 young adults, and 23 adults) were examined. All participants completed a questionnaire to obtain information on their oral health behaviour and life style. Clinical examination was performed to record the number of decayed, missing and filled teeth (DMF-T). Saliva samples were collected for the measurement of sAA and the salivary S. mutans level before and after chewing a gum with or without cherry extract. Statistical evaluation of data was performed. S. mutans and the sAA level of unstimulated saliva samples did not depend on either age or gender. The basal sAA value of adult patients was in linear correlation with the dental caries status. Habitual chewing-gum use decreased the resting sAA and the mean of DMF-T. The number of S. mutans cells was significantly lower in the resting saliva of allergic patients. The applied mechanical and gustatory stimuli by chewing gum resulted in higher sAA and S. mutans levels and a slow decrease of values was observed in the control group for the next 30 min. Thereafter, sAA and S. mutans levels decreased earlier in the presence of sour cherry extract than those of control cases. Chewing gum with sour cherry extract may be useful for the prevention of dental caries.

We evaluated the in vitro activity of posaconazole against nine Candida species using minimum fungicidal concentration (MFC) measurements and time-kill methods.MFCs of posaconazole were determined for 209 clinical isolates (32 Candida albicans, 30 Candida glabrata, 21 Candida tropicalis, 29 Candida krusei, 28 Candida parapsilosis sensu stricto, 50 Candida inconspicua, 13 Candida kefyr, 3 Candida lusitaniae and 3 Candida guilliermondii) and 7 ATCC Candida strains. The following strains were tested in time-kill studies: 3 strains each of C. glabrata, C. kefyr, C. guilliermondii and C. lusitaniae; 2 C. tropicalis; 4 C. albicans; 4 C. inconspicua; 9 C. krusei; 12 C. parapsilosis; and 7 ATCC strains.Posaconazole was fungicidal in both MFC and time-kill experiments (at 2 mg/L within 48 h in time-kill assays) against each C. krusei, C. inconspicua and C. lusitaniae strain and was fungistatic against each C. albicans, C. glabrata, C. tropicalis and C. guilliermondii strain. For the C. parapsilosis strains, posaconazole MFCs wereor=2 mg/L for 20 of the 28 isolates tested; however, in the time-kill tests, even at drug concentrations of 32-64 x MIC, posaconazole was fungistatic against all C. parapsilosis strains tested.MFC values were good predictors of the fungistatic or fungicidal activity of posaconazole, as determined by time-kill curves, for all tested species except C. parapsilosis. Our results highlight the fungicidal action of posaconazole against a number of clinically relevant Candida species.

An in vitro model has been developed for study of cariogenic potential of different Candida species. Slices were prepared from the root of extracted healthy teeth. These disks were covered with inert material, only the central hole, i.e. the root canal dentin surface remained uncovered. These preparates with free root dentin surfaces were incubated in Sabouraud medium in the presence of six-six Candida albicans, Candida glabrata, Candida tropicalis, Candida krusei, Candida inconspicua and Candida norvegensis strains. The calcium release was detected for 15 days. Two types of release could be distinguished. C. albicans deliberated calcium more aggressively (type “A” curve), while other Candidas were characterized by less expressed calcium releasing capacity (type “B” curve). Curves type “A” and “B” were divided into four steps in order to characterize more precisely the different dynamics of calcium release. Analyses of the different steps also suggested the more aggressive behaviour of C. albicans. Our results indicate that in addition to cariogenic role of different bacteria, fungi may also actively take part in the dentinal caries progress.

Fluoroquinolone antibiotics (FQAs) are widely used in dental and medical therapy. Despite their known severe adverse actions on the central and peripheral nervous system, little attention has been directed toward the potential toxic side effects of these compounds on the oral tissues. As the saliva secretion is controlled by the nervous system and neuropeptides, the neurotoxic effect of pefloxacin (PEF), a representative member of FQAs, was studied in rats in the present work. Previously, we demonstrated a significant weight loss of parotid gland tissue, a marked decrease in 3H-thymidine incorporation, a decreased volume of saliva and amylase activity of the glandular tissue in response to PEF. Animals received intraperitoneal injection of PEF (20 mg/100 g body weight daily) for 3 and 7 days. Normal histology, and neurofilament 200, substance P (SP) and calcitonin gene-related polypeptide (CGRP) containing nerve fibers were detected with immunohistochemical methods. A marked decrease of the weights in salivary glands and the acinar diameters were measured. Similarly, a strong and significant decrease of the number of SP and CGRP containing nerve fibers were detected. These findings suggest that the impaired morphology and innervation pattern of salivary glands is related to the neurotoxic adverse effect of FQA treatment.

Paradoxical growth was noted in RPMI 1640 and antibiotic medium 3 in the case of 14 and 1 of 15 Candida tropicalis strains, respectively, at a caspofungin concentration of 12.5 μg/ml using minimum fungicidal concentration tests. Time-kill assays showed that against isolates killed at lower concentrations, caspofungin at a concentration of 12.5 μg/ml was only fungistatic.

Durable clenching on a particular occlusal area may affect the masticatory muscle activity and induce transitional deformation of the dentoalveolar, mandibular and temporomandibular tissues. These effects may provide detectable alterations in the occlusal contact pattern. The aim of this study was to evaluate the subsequent effect of clenching on the number and location of occlusal contacts. This study was carried out on 16 volunteers with correct occlusion and sharply demarcated occlusal contact pattern. The patient closed to intercuspal position with maximal biting force and the occlusal contacts were revealed with a 12 microns thick occlusal foil. Then a gnathometer was placed between the upper and lower incisors and the mouth was closed for two minutes with about 50 N closing force. After that the occlusal contacts were evaluated again. Paired t-test was used to evaluate the data. Both before and after clenching the highest average number of contacts was recorded on the surface of first molars. They were followed in decreasing order by the second molars, second premolars, first premolars, and finally the canines. When the number of contacts was compared in tooth groups, the first molars and the second premolars had more contacts than the second molars and the first premolars. On the surfaces of molars more occlusal contacts were registered after clenching than before. Significant differences were found in case of the left second molar only. It was concluded that durable clenching on a particular occlusal area might change transitionally the distribution of occlusal contacts.

In the last two decades dentists and other dental workers have been called attention to the risk of infection with blood-borne pathogens by a few reports. Before Hepatitis B vaccine became available in 1982, dentists and oral surgeons were reported to have a higher prevalence of Hepatitis B Virus (HBV) than other health-care workers and the general population. The first cases of AIDS were recognised in 1981, and in 1988 dentists infected with Human Immunodeficiency Virus was already registered without any other potential risk factor except his occupation. Hepatitis C Virus (HCV), a positive stranded RNA virus was isolated for the first time from a chronically infected chimpanzee by a human VIII factor concentrate. Now HCV is regarded to be the cause of most cases of non-A-non-B hepatitis. Although the risk of HCV infection among health-care workers is lower than it was in the case of HBV infection, there is some evidence of occupational transmission of HCV. The lack of effective vaccine, the proportion of chronic infections, and the limited success of therapy emphasises the importance of the problem for the dentists in practice. In this report the authors surveyed the epidemiology, transmission, and nature of HCV infection, and suggested some possible connection between the virus and certain oral diseases. The authors expounded some general aspects of management of HCV-infected patients in the dental practice and underlined the importance of preventing occupational transmission.

While antibiotics are broadly used in dental and medical therapy, little attention has been directed towards the potential toxic side effects of antibiotics on tissue regeneration. Here we examined the effect of a quinolone antibiotic, pefloxacin (Rhone Poulenc) on rat parotid gland responses to chronic isoproterenol treatment. Groups of rats received injections of isoproterenol to induce glandular growth, saline (controls), pefloxacin, or isoproterenol and pefloxacin in combination. Parotid gland weight decreased significantly after pefloxacin treatment for 7 days as well as inhibiting glandular enlargement provoked by isoproterenol. The same trend was observed for the rates of DNA synthesis, with the incorporation of [3H]-thymidine in isoproterenol/pefloxacin-treated rats reduced to 49% of isoproterenol treatment alone levels. Saline-treated animals were 42% of the rate of [3H]-thymidine incorporation into DNA observed in isoproterenol treated rats. While isoproterenol treatment increased steady-state mRNA levels for fos, jun, myc, src, c-erbB-2, ras and topo II, inclusion of pefloxacin with the isoproterenol regimen blocked these increases. Pefloxacin treatment by itself did not alter proto-oncogene mRNA levels in the parotid gland. Glandular amylase activity was decreased in the pefloxacin treated group, while the combination of isoproterenol with pefloxacin did not decrease glandular amylase levels to the extent of that observed with β-agonist treatment alone. In acute experiments, pefloxacin significantly decreased the volume of saliva secreted by the parotid gland. These results suggest that quinolone-based antibiotics disturb the secretory function of the parotid gland and can inhibit cell proliferation and regeneration. (Mol Cell Biochem 165: 55–63, 1996)