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Streptococcus salivarius TOVE-R has previously been reported as a successful competitor with Streptococcus mutans 10449S and Streptococcus sobrinus 6715-13 WT on the teeth of rats. We studied, in vitro, some possible bases for this competition, including hydrogen peroxide or catalase production, bacteriocin or enocin production and growth rates. Growth rates were measured spectrophotometrically in both complex and defined media. We studied conditions of (i) aerobic and anaerobic incubation; (ii) glucose and sucrose medium supplementation at three concentrations each; (iii) various initial pH's; (iv) singly- or doubly-inoculated cultures; and (v) half-strength, normal, or double-strength broth used both fresh and as culture filtrates. TOVE-R grew as well as did mutans streptococci at acid pH, decidedly better at alkaline pH, and nearly twice as fast near neutral pH. The average doubling time for TOVE-R was about 0.5 hr, while that for the mutans streptococci was about 1.0 hr. When TOVE-R was grown together with a mutans streptococcus, the growth rate observed for the doubly-inoculated culture was equal to or less than that of TOVE-R alone, never greater. The presence and proportions of both organisms in mixed cultures were confirmed by plate counts, direct specific immunofluorescence, and Nomarski interference microscopy. There was no evidence, by any of the methods employed, to indicate the production of an inhibitory substance against mutans streptococci by TOVE-R, or vice versa. Also, there was no evidence that the faster growth rate of TOVE-R could be attributed to nutrient limitation of the mutans streptococci. TOVE-R's ability to compete successfully with mutans streptococci in vivo may be attributable to its inherent ability to grow faster over a wide range of environmental conditions, as observed in vitro. [ABSTRACT FROM AUTHOR]

The effect of cefotetan on different clinical isolates of Klebsiella has been compared to that of other cephalosporins. The post-antibiotic effect and the effect of pulse-dosing of cefotetan were also tested by an original method whereby the antibiotic was removed with an ion-exchange resin. Finally, the resistance of cefotetan to inactivating enzymes of bacterial origin has been compared with that of other cephalosporins. [ABSTRACT FROM PUBLISHER]

Objectives: The aim of this in vitro study was to evaluate the antimicrobial action of BioPure MTAD (Dentsply Tulsa Dental, Johnson City, TN), Tetraclean, Cloreximid (a mixture of Chlorhexidine (CHX) digluconate and Cetrimide), and 5.25% NaOCl (Ogna Laboratori Farmaceutici, Milano, Italy) against selected endodontic pathogens (Enterococcus faecalis, Porphyromonas gingivalis, and Prevotella intermedia). Materials and Methods: The agar plate diffusion procedure was used to observe the antimibrobial activity of irrigants. Results: Statistical analysis revealed significant effects of the different irrigants on the bacteria colonies. Treatment with 5.25% NaOCl induced a larger zone of microbial inhibition in Prevotella intermedia and Porphyromonas gingivalis (Tukey HSD post-test, P = 0.0001) when compare to MTAD, Tetraclean and CHX. Anyway, MTAD and Tetraclean were more effective to inhibit bacterial growth compared to CHX (P < 0.0001, Tukey HSD post-test). Furthermore, post hoc analysis revealed that MTAD and Tetraclean induced the largest zone of microbial inhibition of Enterococcus faecalis cultured under both aerobic and anaerobic conditions, when compared with 2% CHX and NaOCl (P < 0.0001, Tukey HSD post-test). The control group showed no microbial inhibition. Conclusion: 5.25% NaOCl showed a high antimicrobial activity against anaerobic bacteria. MTAD and Tetraclean showed a high action against both, strictly anaerobic and facultative anaerobic bacteria. Chlorexidine + Cetrimide (Cloreximid) showed the lowest antibacterial activity against both, facultative and strictly anaerobic bacteria tested.

Objective: The aim of the present report is to report an unusual case of chondroid metaplasia of the dental pulp., Study Design: A white 45-year-old female patient appeared with signs and symptoms of an irreversible pulpitis on an upper left decayed third molar. After extraction, the tooth was fixed, demineralized, and processed for light microscopy., Results: Pulp tissue was replaced at one of the pulp horns by a colliquative necrosis surrounded by neutrophil leucocytes and congested blood vessels. Serial sections demonstrated a complete opening of the decayed tooth to the oral environment, and an area of chondroid metaplasia of the pulp was evident. Chondroid tissue was surrounded by a dense concentration of chronic inflammation cells., Conclusions: According to the best knowledge of the authors, this is possibly the first report of an occurrence of chondroid metaplasia in the dental pulp. This metaplasia could be the result of an attempt at tissue repair by the pulp tissue injured by the carious lesion. The pathologic changes in the dental pulp could have activated some of the mechanisms that have been described in other tissues, producing the formation of chondroid tissue. Pulp tissue may adapt to changed environmental stimuli by a deviation from normal cell differentiation.

In nonimmunocompromised patients aspergillosis of the paranasal sinuses is a relatively rare disease. Root canal treated teeth with overextension of the root canal sealer or solid materials such as gutta-percha or silver cones into the sinus might be the main etiological factor for aspergillosis of the maxillary sinus in healthy patients. Root-filling materials based zinc oxide-eugenol is considered to be a growth factor for aspergillus. Aspergillus fumigatus needs heavy metals such as zinc oxide for proliferation and metabolism. Prognostic and histological studies showed that instrumentation and obturation should not extend beyond the apical foramen. When the sealer and/or gutta-percha is extruded within the sinus, this produce an inflammatory reaction and then Aspergillus growth. We report one case of healthy 60-yr-old male with overextension of root canal sealer in maxillary sinus. After surgical procedure, microscopic examination revealed aspergillosis. Overextension into the maxillary sinus with root canal cements has to be avoided.

Objectives: We sought to characterize the prevalence of Russell bodies in specimens clinically diagnosed as pulpitis., Study Design: Forty-five teeth with symptomatic irreversible pulpitis were extracted, fixed, and demineralized. Five nonsymptomatic human teeth extracted for orthodontic purposes were used as controls. All teeth were then processed for light microscopy, for which they were stained variously, or for transmission electron microscopy (TEM)., Results: There was no evidence of Russell bodies in the pulp of 5 nonsymptomatic human teeth. Russell bodies, however, were detected in 31/45 (69%) of pulpitis specimens examined by light microscopy. The basic stains safranin and fucsin gave better visualisation of them than other staining procedures. All pulpitis specimens were histologically characterized as having the features of chronic inflammation. Of 5 specimens of pulpitis teeth evaluated by TEM, all exhibited Russell bodies. There was no morphological distinction among the Russell bodies when view either by light or electron microscopy. These structures appeared either within rough endoplasmic reticulum (RER) or they were found in extracellular stroma, suggesting their association with the lysis of cells., Conclusions: Russell bodies are prevalent in pulpitis samples with histological features of chronic inflammation, but are not found in all such samples. Russell bodies may not have been frequently detected in the past due to the types of stains employed in histolopathological study of pulps. The mechanistic basis of the association of Russell bodies with the symptoms of irreversible pulpitis is not clear.

Background: The easiest defence system carried out by the organism, the inflammatory response, happens with the support of phagocyting cells: the polymorphonuclear leukocytes (PMNL) or neutrophils are the most important cell line acting as the first defence of the organism against bacterial agents. Previous studies have shown a correlation between a reduction of the immune function and development of periodontal disease. Furthermore, it is well known that transplant patients show a variety of oral lesions as a consequence of their therapy, in particular to immunosuppressive drugs. The aim of this study is to evaluate the phagocytosis and killing functions of PMNL in transplant patients and in patients with periodontal disease in comparison with a group of healthy subjects., Methods: PMNL, were isolated by spontaneous sedimentation from heparinized blood and centrifugation of plasma on density medium. Phagocytosis rate was expressed as the percentage of Candida albicans phagocyted after 20' incubation and phagocyting PMNLs. Intracellular killing was expressed as the percentage of yeast cells killed., Results: We did not find a significant decrease of phagocytosis in transplant patients and patients with periodontal disease while these two groups of patients showed a decrease of PMNL killing activity in respect to healthy controls, an effect which was unrelated to the severity of periodontal disease., Conclusions: These results suggest that a reduction of killing activity, either spontaneous or drug-induced, would contribute to the development of periodontal disease.

Background: HCV-RNA occurrence in saliva of patients suffering from C hepatitis induced to consider saliva as a possible diffusion mean of this disease., Methods: Saliva and blood samples from 32 C hepatitis seropositive patients, followed for odontostomatologic problems in Odontoiatric Clinic of Brescia University were obtained. In every blood and saliva sample HCV-RNA concentration was evaluated following HCV-RNA 2.0 Assay (bDNA) Quantiplex test (Chiron), in Microbiology Institute of Brescia University., Results: All patients showing HCV-RNA in serum presented virus in saliva also; two patients with negative HCV-RNA serum presented virus in saliva. In latter cases, we supposed that viral concentration in serum was under sensibility threshold of employed method., Conclusions: Saliva appears an easily and not invasively obtainable medium for epidemiological studies on HCV diffusion in humans. Its role in C hepatitis transmission, on the contrary, has not been cleared till now.

Background: This study aims to define the influence of chlorhexidine on taste, considering either its concentration in mouthwashes or time of rinsing., Methods: Suprathreshold taste acuity of 40 healthy subjects tasting variously concentrated solutions of sucrose, sodium chloride, citric acid and quinine hydrochloride was determined. Subjects were divided into four groups. Three groups rinsed their mouths during one minute, twice a day, for seven days, with a selected mouthwash (respectively 0.12%, 0.20%, and 0.30% chlorhexidine solutions). The fourth group rinsed in the same manner with a 0.30% chlorhexidine mouthwash, and time of rinsing was 15"., Results: All the mouthwashes reduced taste acuity for salt and bitter; the perception of sweet and sour was not significantly modified. Chlorhexidine acted on taste in different ways: salt perception reached the lowest value on the second day of treatment and the degree of hypogeusia changed no more till mouthrinses were interrupted. Bitter perception was progressively reduced and reached the lowest value on the seventh day. In both cases taste reduction lasted some days after the interruption of mouthrinses. Quality of all tastes was altered by mouthwashes, but incidence of dysgeusia was not related to chlorhexidine concentration., Conclusions: Hypogeusia induced by chlorhexidine concerns specifically salt and bitter. Chlorhexidine concentration in mouthwashes till 0.12% and mucosa exposure not exceeding 60" twice a day, seem the best procedure to protect tastes in clinical practice.

Leukocyte adhesion deficiency is a rare inherited defect of phagocytic function resulting from a lack of leukocyte cell surface expression of beta2 integrin molecules (CD11 and CD18) that are essential for leukocyte adhesion to endothelial cells and chemotaxis. A small number of patients with leukocyte adhesion deficiency-1 have a milder defect, with residual expression of CD18. These patients tend to survive beyond infancy; they manifest progressive severe periodontitis, alveolar bone loss, periodontal pocket formation, and partial or total premature loss of the primary and permanent dentitions. We report on a 13-year-old boy with moderate leukocyte adhesion deficiency-1 and severe prepubertal periodontitis. This case illustrates the need for the dentist to work closely with the pediatrician in the prevention of premature tooth loss and control of oral infection in these patients.

Background: Attempts to detect Helicobacter pylori in dental plaque have given contrasting results, and the possibility of an oral-oral transmission of the infection remains unclear. In this study, a sensitive and specific immunoperoxidase method has been employed to assess the presence of H. pylori in dental plaque., Methods: Dental plaque smears from 80 patients undergoing gastroscopy were analyzed by an indirect immunoperoxidase test, employing a mixture of two monoclonal antibodies against H. pylori., Results: No immunostained bacteria were shown in any of the examined dental plaque samples., Conclusions: H. pylori is not usually present in dental plaque, indicating that oral-oral transmission of the infection could be due to intermittent esophageal reflux only.

Taste anomalies have not been systematically investigated till recently in Italy. The influence of the taste on the choice of the foods, on the nutrition and on the same psycho-physic human mindedness has largely been demonstrated. In this study, taste anomalies associated with various pathologic conditions (nervous, endocrine, metabolic, infectious, immunological, carential or neoplastic disorders) are reported, as well as those produced by drugs, or surgical interventions. The type and the degree of taste anomalies associated to immunological diseases, allogeneic bone marrow transplantation and AL amyloidosis are particularly described.

The evolution and the improvement of the surgical techniques and pharmacological therapies brought to new patients categories, also in odontoiatric field for example patients who underwent organ transplantation. Among the patients, we wanted to dwell our attention on pediatric patients after liver transplantation, by light of the new therapeutic outlines modifications. In fact in these young patients it is possible to observe, besides the severe systemic consequences, also the involvement of the oral cavity. After the transplantation, the immunosuppressive therapy is set up and it is based on the use of cyclosporine with the possible azotiopine or steroid association. The cyclosporine side-effects are well known and, among these, the gingival hyperplasia. FK506 is a drug recently introduced, it is a strong immunosuppressor. Therefore we began to estimate patients who assumed FK 506, in order to compare the effect at the gingival level among patients who follow a cyclosporine therapy.

Periodontal disease, an affection of bacterial etiology, causes the destruction of the periodontal tissue. From both the diagnostic and the prognostic points of view, it is extremely important to evaluate the changes occurring in the alveolar bone in patients affected with periodontal disease. The information obtained by conventional radiographic techniques is usually poor due to the overlapping of anatomical structures and to the lack of an axial view of the structures. CT, thanks to millimetrical sections of the dental structures along the planes which parallel the hard palate, allows the evaluation of: 1) the size and the relationship between teeth roots, with no overlapping of anatomical structures; 2) bone thickness; 3) very early bone lesions around the teeth roots. The authors suggest CT as a valuable tool in the study of periodontal disease in its early stage and in the evaluation of advanced lesions, both before treatment and during follow-up, when it is important to check the results of conservative treatment.

The Authors describe the clinical case in which a 30 years old male patient presents anomalous pigmentation of the oral mucosa after the endodontic treatment of the upper right central incisive. The mucosa's anomaly appeared at the height of the lower third of the root near the branch of an accessory endodontic canal previously filled and it was caused by the outlet of filling material. After the examination of this case, the Authors affirme the importance of an accurate anamnesis in order to obtain a correct diagnosis of the various kinds of pigmented lesions, distinguishing the etiology, the pathogenesis and the histologic patterns.

The authors discuss the feasibility of using ultrasonography in the early diagnosis of congenital dysplasia of the hip. Having used the methods of Graf and Harcke, they devised a new scan which always reveals the state of the limbus in neonatal congenital dysplasia. This has been used for two years as an additional technique in neonates with a positive Ortolani click to demonstrate the presence of an inverted limbus, which is not revealed in the Graf and Harcke scans although they give a very good overall picture of the femoral head and acetabulum. The disclosure of an inverted limbus at this early stage is of crucial importance in determining the correct treatment to be adopted.

The effect of ceftriaxone against Gram-negative and Gram-positive strains of different clinical isolates has been compared to that of other cephalosporins such as cefuroxime, cefoxitin and cefotaxime. Cefotaxime and ceftriaxone have a notably higher activity against Enterobacteriaceae than cefuroxime and cefoxitin. If ceftriaxone activity is compared to cefotaxime activity, it may be seen that the former shows a stronger action against Pseudomonas, Proteus rettgeri, Enterobacter and Serratia. Against Staphylococcus aureus and enterococci the four antibiotics show a low level of activity. The effect of a microorganism's temporary contact with ceftriaxone was tested by a method whereby the antibiotic was removed with an ion-exchanging resin. Ceftriaxone shows rapid bactericidal activity against sensitive bacteria and if it is used at concentrations slightly higher than MIC, as in vivo against bacteria of average sensibility, we notice a 10-18 h bacteriostatic effect during which a prevalence of filamentous shapes of gram-negative bacteria is observed.