Frequency and distribution of root filled teeth and apical periodontitis in a Greek population.

AIM: To investigate the prevalence of root filled teeth and apical periodontitis (AP) in a Greek population. METHODOLOGY: A random sample of 320 patients who required full mouth periapical radiographic examination as a part of diagnostic and planning procedures were included. The age of the patients ranged from 16 to 77 years. A total of 7664 teeth were assessed and the frequency of root filled teeth and periapical status was recorded. Two observers evaluated the radiographs under standardized conditions. AP was defined as distinct periapical radiolucency or widening of the periodontal ligament space exceeding two times the normal width. Statistical evaluation of differences in proportions between groups was performed using random effects logistic regression models. RESULTS: The periapical status of 286 (3.7%) teeth was impossible to evaluate because of radiographic faults; these teeth were excluded from further analysis. A total of 1040 (13.6%) teeth had radiographic signs of AP and 680 (9.2%) teeth had been root filled. Of the root filled teeth, 408 (60.0%) had AP. There was no difference in the number of root filled teeth between males and females; the prevalence of root filled teeth increased with age. Significantly more molars (13.1%) and premolars (11.9%) than anterior teeth (5.8%) had been root filled (P < 0.001). The prevalence of AP was significantly higher (P < 0.001) in molars (23.9%) and premolars (14.0%) than anterior teeth (9.4%). CONCLUSIONS: The prevalence of AP and the frequency of root filled teeth with AP in this Greek population were higher than those found in many other European countries. The frequency of root filled teeth was comparable with findings in other epidemiological studies.

The influence of root-end resection and root-end cavity preparation on microleakage of root filled teeth in vitro.

AIM: To investigate in vitro the influence of root-end resection and root-end cavity preparation on leakage of root filled teeth. METHODOLOGY: The root canals of 48 roots, 16 mandibular premolars (G1), 16 mandibular incisors (G2) and 16 maxillary incisors (G3), 12 mm in length, were enlarged using a modified 'balanced force' technique and filled with gutta-percha and sealer using lateral compaction. After setting, leakage along the canal was measured using a fluid transport model. Root-end resection and root-end cavity preparation were then performed, leaving roots 10 mm in length with root fillings of 7 mm (groups R1, R2 and R3, respectively). Fluid transport was measured again along the remaining root fillings of all groups using the same experimental conditions. Results of leakage before and after root-end resection were analysed statistically using the Kruskal-Wallis and Wilcoxon tests. RESULTS: A total of 31% of the roots leaked before and 54% after root-end preparation; the difference was significantly different (P < 0.001). No significant differences were found either among groups G1, G2, G3 (P = 0.565) or among groups R1, R2, R3 (P =0.2628). Significant differences, however, were shown between groups G1-R1 (P = 0.0053), G2-R2 (P =0.0089) and G3-R3 (P = 0.0461). CONCLUSIONS: Root-end resection and root-end cavity preparation compromised the seal of 7 mm root fillings in all tooth groups. Increased leakage was recorded in the following order: mandibular incisors > mandibular premolars > maxillary incisors.

Plasma levels of soluble cellular adhesion molecules in patients with arterial hypertension. Correlations with plasma endothelin-1.

Background: Several reports have shown that circulating, soluble cellular adhesion molecules and endothelin-1 (ET-1) are implicated in the pathophysiological events of atherosclerosis and may reflect the endothelial dysfunction characterizing this disorder. Methods: To evaluate the expression of these factors in arterial hypertension (AH), we measured plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble P-selectin (sP-selectin), and ET-1 in 60 untreated patients with mild to moderate AH (hypercholesterolemic: n=31, normocholesterolemic: n=29) and 30 sex- and age-matched normocholesterolemic normotensive controls. Results: Hypertensive patients exhibited significantly higher levels of sICAM-1 (234+/-21 vs. 187+/-12 ng/ml, P<0.005), sVCAM-1 (681+/-42 vs. 589+/-23 ng/ml, P<0.005), sP-selectin (89+/-17 vs. 55+/-11 ng/ml, P<0.01) and ET-1 (6.2+/-0.7 vs. 2.4+/-0.3 pg/ml, P<0.01) than did normotensive controls. The normocholesterolemic hypertensives had lower levels of sICAM-1, sVCAM-1 (P<0.01), sP-selectin and ET-1 (P<0.05) than hypercholesterolemic hypertensives, but higher levels than normotensive controls (P<0.05). In hypertensives, plasma ET-1 was significantly correlated with mean arterial pressure (r=0.51, P<0.03) and sICAM-1 levels (r=0.64, P<0.01). In hypercholesterolemic hypertensives, LDL cholesterol was also significantly correlated with plasma levels of sICAM-1 (r=0.53, P<0.04) and sP-selectin (r=0.41, P<0.05). Conclusions: Plasma levels of soluble cellular adhesion molecules are elevated in hypertensive patients in comparison to normotensive controls and may be related to plasma ET-1 activity. The coexistence of hypercholesterolemia may enhance the plasma soluble adhesion molecule activity induced by AH.

Dye penetration in dry and water-filled gaps along root fillings.

AIM: The aim of this study was to investigate the influence of hydration in voids along root fillings on methylene blue penetration. METHODOLOGY: A total of 80 human root canals were prepared using a step-back technique and filled with a zinc oxide based sealer and gutta-percha. Leakage along the fillings was measured by a transport fluid model and classified into three categories: gross leakage (GL), slight leakage (SL) and no leakage (NL). Specimens with NL and SL were immersed into methylene blue (MB) 2% for 24 h (group I). Specimens with GL which had wide gaps filled with water were randomly divided into two groups (II, III). Transport air was applied to remove water from gaps only in specimens of group III. All tested specimens from groups II and III were also immersed into MB 2% for 24 h. Each specimen was then split longitudinally and linear measurements of dye penetration were recorded. RESULTS: Group III (with dry gaps) showed significantly more dye penetration than group II. No significant difference was found between group I and group II. CONCLUSIONS: Methylene blue penetrates along root fillings more easily in dry gaps than in water-filled gaps.

Correlation of interleukin-6 gene expression to immunologic features in patients with cardiac myxomas.

Cardiac myxomas, the most common primary heart tumors in adults, show a variety of clinical manifestations and laboratory findings correlated with elevated interleukin-6 (IL-6) serum concentration. The aim of this study was to determine the expression of IL-6 mRNA in myxoma tissue as a cause to frequent immunologic abnormalities in patients with such tumors. In our centers, we analyzed 17 surgically resected myxomas using the polymerase chain reaction (PCR) and found increased IL-6 mRNA expression in 14 of 17 cases. The serum IL-6 levels of the 14 patients, detected by enzyme-linked immunosorbent assay (ELISA) with mouse antihuman monoclonal antibody (mAb), were high preoperatively (> 6 pg/ml) and decreased to normal postoperatively (< or = 6 pg/ml). These same 14 patients exhibited significant autoimmune disorders preoperatively. The other 3 patients had normal serum levels of IL-6 (< or = 6 pg/ml) and did not present any serious signs and symptoms, and molecular analysis did not show overexpression of IL-6 mRNA in neoplasmic tissue. These results suggest that IL-6 is overproduced in myxoma tissue and secreted into the systemic circulation as a stimulator of the immunoregulatory system. Furthermore, this study indicates the promising role of molecular biology techniques in the research of pathophysiologic mechanisms of cardiac myxomas.

In vitro study of the indirect action of calcium hydroxide on the anaerobic flora of the root canal.

The aim of this study was to evaluate in vitro a possible mechanism involved in the antimicrobial action of calcium hydroxide, namely absorption of carbon dioxide from the root canal. Twenty obligate and 20 facultative anaerobic bacteria isolated from infected root canals and identified to species level were used. For each bacterial species a standard concentration was achieved and 0.1 ml of the inoculum was spread on blood agar plates, which were consecutively incubated in an anaerobic chamber for 5-7 days. One experimental and one control group were studied: the experimental group included one plate with the bacterial species as well as one open plate containing 32 g calcium hydroxide paste at a mixing ratio of 6:4. Both plates were incubated in an anaerobic chamber for 72 h. The control group included only one plate containing the same bacterial species and was incubated under the same conditions. After a 72-h incubation, the number of the recovered bacteria were counted in both groups. Statistical analysis showed that the number of bacteria recovered from the control group was significantly lower than that of the experimental group, but no particular resistance of any bacterial species to calcium hydroxide could be detected. This finding strongly suggests that the ability of calcium hydroxide to absorb carbon dioxide may contribute to its antibacterial activity.

Effect of thickness on the sealing ability of some root canal sealers.

A fluid transport model study was used to evaluate the sealing ability of five root canal sealers, AH 26, Sealapex, Ketac Endo, Roth, and Kerr EWT, and a dental bonding agent at thicknesses of 0.05 mm (thin layer) and 0.3 mm (thick layer) with 270 standard human root sections obturated with sealer combined with standard gutta-percha cylinders. AH26 and Sealapex sealed more tightly in thick layers, whereas Ketac Endo, Johnson and Johnson Bonding Agent, Roth, and Kerr EWT sealed more tightly in thin layers. In thin layers J&J Bonding sealed more tightly than any other sealer tested. In thick layers AH 26 and Sealapex sealed more tightly than Ketac Endo and J&J Bonding Agent, and these sealed more tightly than Roth and Kerr EWT. These findings indicate that the thickness of the sealer layer significantly influences the sealing of a root canal filling and that the influence of thickness varies depending on the type of sealer.

Evaluation of the antimicrobial effectiveness of citric acid and sodium hypochlorite on the anaerobic flora of the infected root canal.

This study was designed to evaluate the antimicrobial effectiveness of 25% citric acid, compared with 2.5% sodium hypochlorite, after time intervals of 5, 15, 30 and 60 min. Anaerobic bacterial species were isolated from infected root canals and categorized according to Gram stain as Gram-positive cocci, Gram-negative cocci, Gram-positive rods and Gram-negative rods. The experimental method used was similar to that proposed by the German Society for Hygiene and Microbiology (DGHM) with slight modifications. Testing revealed that citric acid does demonstrate antimicrobial properties against anaerobic bacteria, especially against cocci, but it is less effective than 2.5% sodium hypochlorite.

Study of the apices of human permanent teeth with the use of a scanning electron microscope.

The apical region of the roots of 38 maxillary incisors, 25 mandibular incisors, 29 maxillary second premolars, 92 mandibular first and second premolars, 12 maxillary first molars, and 17 mandibular first molars were prepared and studied with the use of a scanning electron microscope. The number and size of the main apical foramina, their distance from the anatomic apex, and the existence and size of accessory foramina were recorded, summarized, and statistically analyzed. More than one main foramen was observed in all groups except for the palatal root of maxillary molars and the distal root of mandibular molars. Accessory foramina were also observed in all groups of teeth. The distal roots of mandibular molars had the largest size main foramen (mean value, 392 microns), whereas the maxillary premolars had the largest accessory foramina (mean value, 53.4 microns) and the most complicated apical morphologic makeup. The distance of the main foramen from the anatomic apex never exceeded 1 mm. The highest values were observed at the mandibular incisors (978 microns), the distal root of mandibular molars (818 microns), and the upper premolars (816 microns). All values showed satisfactory fitting to normal distribution.

In vitro evaluation of the effectiveness of calcium hydroxide and paramonochlorophenol on anaerobic bacteria from the root canal.

The effectiveness of calcium hydroxide and paramonochlorophenol (PMCP) was tested on anaerobic bacteria isolated from infected root canals, at time intervals 5, 15, 30 and 60 min. The experimental method used was similar to that proposed by the German Society of Hygiene and Microbiology (DGHM), with slight modifications. Testing revealed that calcium hydroxide was significantly more effective than PMCP against the total number of anaerobes. Additionally, it was proved to be quickly and highly effective against some microorganisms related to severe clinical symptoms, such as B. melaninogenicus and P. gingivalis, as well as against actinomyces species.

Unusual case of general pulp calcification (pulp stones) in a young Greek girl.

An unusual case of generalized pulp calcification is reported in a 14-year-old Greek girl. Radiographic examination revealed large pulp stones in all permanent teeth located in the pulp chamber and sometimes extending to the coronal portion of the root canal. The patient's dental, medical and family history, as well as the findings from the clinical examination were non-contributory. Biochemical analysis of one pulp stone removed from the right maxillary central incisor revealed large amounts of urates, proteins and phospholipids, but a blood test of the patient showed no metabolic disturbance. Therefore, it is suggested that this unusual case may be of idiopathic origin.

[The reliability of electrical and thermal pulp tests. A clinical study]. / Klinikostatistike melete tes axiopistias ton dokimasion zotikotetas tou polphou.

A clinical study was conducted to assess the reliability of electrical and thermal pulp tests and to correlate the results with the true pulp status, as this was proved after the access opening, as well as to determine which clinical factors might be associated with the tests reliability. The results showed that pulp tests are reliable in a high grade and that there is no significant difference in their reliability.

[Pain after obturation of the root canals]. / Odontoponos meta to peras tes endodontikes therapeias.

This study was conducted to determine the incidence and degree of postobturation pain and to determine whether there is a significant relationship between pain and any clinical factors or conditions existing before, during, or at the completion of the root canal therapy. Of the 239 patients included in the study, 203 (84.9%) had no pain during the first 48 hours, 26 (10.9%) had slight pain, 5 (2.1%) had moderate pain and 5 (2.1%) had severe pain. Thirty days after obturation 3 patients had slight pain, 2 patients moderate pain and only one patient had severe pain. Meanwhile, we had to repeat the root canal therapy in 3 cases. Significant relationships were found between postobturation pain and obturation of the root canal past the apical foramen.