Antimicrobial effectiveness of polyhexamethylene biguanide on Enterococcus faecalis, Staphylococcus epidermidis and Candida albicans.

Aim To evaluate the antimicrobial activity of 0.2% polyhexamethilene biguanide (PHMB) in root canal models infected with Enterococcus faecalis, Candida albicans and Staphylococcus epidermidis. PHMB was compared in these tests with 2.5% NaOCl and 0.2% CHX. Methods Prepared models of 50 human root canals (n=50) were immerged in mixed, four- weeks old culture that consisted of E .faecalis, S. epidermidis and C. albicans. Roots were randomly divided into three groups: one with 30 (n=30) and two with 10 (n=10) samples. Samples were treated with polyhexamethylene biguanide (PHMB) (0.2%), sodium hypochlorite (NaOCl) (2.5%) and chlorhexidine (CHX) (0.2%), respectively. Root dentin was sampled before and after the tretment with these solutions. Colony- forming units (CFU) were counted to asses the antimicrobial effects of three solutions on viability of selected microrganisms in specimens before and after the treatment.T-test was used for comparison of results between specimens before and after the treatment, while Newman-Keuls test was used for pairwise comparison at p=0.05. Results The PHMB was significantly more efficient in reducing the number of all three tested microorganisms. NaOCl and CHX made only statistically significant (p<0.05) difference in case of E. faecalis and S. epidermidis. In the case of C. albicans, this difference was not statistically significant due to the small number of positive samples and high initial dispersion of results. Conclusion Both solutions PHMB and NaOCl were successful in eliminating E. faecalis and S. epidermidis from the mature dentin biofilm, CHX was not successful enough.

Electric pulp test threshold responses in healthy incisors, canines, premolars and molars.

The purpose of this study was to determine the range of threshold responses of healthy dental pulps and test the reproducibility of the electric pulp test (EPT). Forty-nine dental students participated in the study. Sound teeth in both arches, except third molars, were included. The teeth were isolated using cotton rolls and dried with compressed air, and the threshold responses were recorded. Participants stopped the stimulus increase by pressing the switch at the first sensation of discomfort. The measurements were repeated after 30 days. The obtained data were analysed using SPSS® 16.0. The mean thresholds for the maxillary incisors, canines, premolars and molars were 10.77, 21.07, 21.88 and 34.07 µA, and for mandibular incisors, canines, premolars and molars 9.81, 18.7, 19.24 and 30.1 µA respectively. The differences between the two measurements were statistically significant for teeth 32, 31, 41 and 42. The EPT was shown to be reproducible for all the teeth tested except mandibular incisors.

Frequency of bacetrial content finding in persistant periapical lesions.

OBJECTIVES: To determine the percentage of persistant apical lesions positive for bacterial nucleic acids, to detect microorganisms difficult to cultivate in persistant apical lesions by PCR and relate them to endodontic failure, clinical symptoms and diabetes mellitus. MATERIALS AND METHODS: The samples of persistent apical lesions were collected during apicoectomy. Bacterial ubiquitous primer 16S rRNA was used to detect 16S ribosomal RNA in 36 samples. A species-specific PCR was performed with primers targeted to the bacterial 16S rRNA genes of Prevotella Nigrescens, Pseudoramibacter alactolyticus, and Propionobacterium propionicum. RESULTS: Six samples (16.67%) were positive for bacterial ribosomal RNA. Pseudoramibacter alactolyticus was detected in three samples. Propionibacterium propionicum and Prevotella nigrescens were detected in one sample each. The prevalence of infection of such lesions with P. intermedia, P. propionicum and P. alactolyticus is low. CONSLUSION: The study we conducted gave insufficient data about extraradicular infection and its connection with diabetes mellitus and clinical symptoms. CONCLUSIONS: Apical lesions persisting after endodontic treatment could harbor microorganisms other than Actinomyces and Propionicum species.

Radiomorphometric indices of mandibular bones in an 18th century population.

OBJECTIVE: To estimate four radiomorphometric indices of mandibular bones in an 18th century population sample, and possibly associate the findings with bone mass loss related to sex, age, nutritional habits and pathologies reflecting on the bone. DESIGN: Thirty-six sculls (31 males, 5 females), recovered from the crypt of Pozega Cathedral in Croatia were analyzed. Age estimation was based on tooth wear, and Eichner class was determined according to the number of occlusal supporting zones. The parameters in recording analogue orthopantomographs were set to constant current of 16 mA, exposure time of 14.1s, and voltage between 62-78 kV. Films were processed in an automatic dark chamber processor for 12 min, and digitized at 8-bit, 300 dpi. The thickness of the mandibular cortex was assessed below the mental foramen (MI), at antegonion (AI), at gonion (GI). Qualitative mandibular cortical index (MCI) was assessed. RESULTS: Average values of MI, AI and GI were 3.97 ± 0.94 mm, 2.98 ± 0.56 mm, and 1.99 ± 0.55 mm, respectively. Statistically significant differences between males and females were found for AI right (p=0.014), GI left (p=0.010) and GI average (p=0.006), and were in all cases higher in males. There were no statistically significant differences between age groups for either index (p>0.05). Considering Eichner classification the differences were not significant for MI (p=0.422), AI (p=0.516), and GI (p=0.443), but in Eichner classes II, MCI was significantly higher (p=0.02). CONCLUSION: The obtained data does not suggest generalized malnutrition or calcium, phosphorus and vitamin D deprivation in the historic population studied.

Prevalence of apical periodontitis and quality of root canal fillings in population of Zagreb, Croatia: a cross-sectional study.

AIM: To determine the prevalence of apical periodontitis and assess the quality of endodontic fillings in the population of the city of Zagreb, Croatia. METHODS: A total of 1462 orthopantomograms from new patients at 6 different dental practices was analyzed during 2006 and 2007. The presence of periapical lesions was determined by using the periapical index score (PAI). The quality of endodontic fillings was assessed according to the filling length and homogenicity. Data were analyzed using t test and ANOVA with Scheffe post-hoc test. RESULTS: There were 75.9% of participants with endodontically treated teeth and 8.5% of all teeth were endodontically treated. Only 34.2% of endodontically treated roots had adequate root canal filling length, while 36.2% of root canal fillings had homogenous appearance. From the total number of teeth with intracanal post, 17.5% had no visible root canal filling. Using PAI 3 as a threshold value for apical periodontitis, periapical lesions were detected in 8.5% of teeth. Adequate quality of root canal fillings was associated with a lower prevalence of periapical lesions. CONCLUSION: We found a large proportion of endodontically treated teeth with apical periodontitis and a correlation between the quality of endodontic filling and the prevalence of periapical lesions. This all suggests that it is necessary to improve the quality of endodontic treatment in order to reduce the incidence and prevalence of apical periodontitis.

Dose- and mode-dependent effect of halogen dental curing blue light on the V79-cell line.

The aim of this study was to evaluate the time and dose dependent effect of halogen light from dental curing unit on the cell viability, colony-forming ability and proliferation of the V79 cell culture. The investigation included the medium mode (M), exponential (E) and standard (S) illumination mode for 20, 40 and 80 seconds. The viability was determined using the trypan blue exclusion test. Colony forming ability was assessed by colony count on post-exposure day 7. Cell proliferation was determined by cell counts during five post-exposure days. The viability of cells was not affected by blue light in view of exposure time and modes. Colony forming ability in treated cells was slightly, but not significantly lower than in control cells. Cell proliferation was lower in cells exposed to the M mode for 80 s on post-exposure day 3 and 4 (p < 0.05). On the same post-exposure days, the proliferation of cells exposed to modes E and S, showed a significant inhibition after 20, 40 and 80 s of exposure (p < 0.05). Disrupted cellular functionality and no significant decrease in colony forming ability of V79 cells in addition to time- and dose dependent significant inhibition of cell proliferation might be ascribed to the photocuring blue light activity and/or changes in temperature during the course of experiment in vitro.

[Temporomandibular disorders and headaches]. / Temporomandibularni poremecaji i glavobolje.

Temporomandibular disorder (TMD) is a common name for a series of pathologic conditions with similar signs and symptoms, which can lead to a disturbed and altered function of the stomatognathic system. Most of these conditions are of a multifactorial etiology, which can pose difficulties in obtaining a precise and accurate diagnosis. However, TMD is an ever more common and serious problem in contemporary dental practice and at general medical offices, so a more systematic approach in its diagnosis including data collection and interpretation is necessary. Accordingly, accurate diagnosis of TMD requires proper identification and classification of the dysfunction, as well as recognition of the mechanism and origin of pain occurrence.

Estrogen receptors in human pulp tissue.

OBJECTIVE: The aim of this study was to evaluate the expression of estrogen receptor (ER)-alpha in human pulp tissue. STUDY DESIGN: Tissue samples were collected from 51 teeth extracted for orthodontic reasons or from endodontically treated teeth. Immunohistochemical staining was performed with mouse antihuman ER-alpha 1D5 by using the alkaline phosphatase antialkaline phosphatase technique. Immunohistochemical reactivity was semiquantitatively assessed and graded on an intensity scale of 0 to 3. RESULTS: ERs were found in odontoblasts, endothelial cells, and Schwann cells. By means of statistical analysis, ERs were found to be common in odontoblasts (1.3-1.6) and in endothelial cells (1.0-1.4), whereas in Schwann cells they were somewhat rare (0.7-1.1). Difference in expression of ERs was not found among patients in different age groups. With respect to sex, a difference in reactivity was observed in Schwann cells, which showed higher reactivity in female pulps. CONCLUSION: The results of this study confirm the expression of ER-alpha in the human dental pulp.