Elevated expression of Cu, Zn-SOD and Mn-SOD mRNA in inflamed dental pulp tissue.

AIM: To determine the mRNA expression levels of copper-zinc superoxide dismutase (Cu, Zn-SOD) and manganese SOD (Mn-SOD) in healthy and inflamed human dental pulp tissue. METHODOLOGY: Sixteen patients with symptomatic irreversible pulpitis (eight females and eight males) were selected for study. Normal healthy pulps were removed from extracted mandibular third molar teeth from 10 systemically healthy individuals (six females and four males). QRT-PCR analysis of Cu, Zn-SOD and Mn-SOD mRNA expression was carried out in 16 cases of irreversible pulpitis and in 10 cases of systemically healthy donors. The Shapiro-Wilk's test was used to test the normality of data, whereas the Mann-Whitney U-test was used to evaluate the significance of the differences between groups. Differences in the expression levels were considered to be statistically significant for P-values <0.05. RESULTS: A significant increase (P < 0.05) occurred in both Cu, Zn-SOD and Mn-SOD mRNA expression in cases of irreversible pulpitis. The increase in Mn-SOD level was significantly higher (P < 0.05) than the change observed for Cu, Zn-SOD. CONCLUSIONS: The development of pulpitis is associated with elevated transcription of both Cu, Zn-SOD and Mn-SOD; pulp tissue inflammation generated higher Mn-SOD transcription compared with Cu, Zn-SOD.

Ruptured cerebral aneurysm in the early stage of life--a congenital origin?

We report the case of a large fusiform aneurysm of the anterior cerebral artery in a 3-month-old girl presenting with generalized seizures and complicated by a cardiorespiratory arrest needing resuscitation. The native cerebral CT scan revealed a diffuse subarachnoid hemorrhage (Fischer III grade); CT angiography showed an aneurysm of the distal A1 segment of the anterior cerebral artery (ACA). Successful treatment was achieved through surgical trapping of the aneurysm and sacrifice of the distal A1 segment. A histological study of the aneurysmal wall revealed the absence of elastic fibers in an otherwise fibromuscular media and showed no signs of previous hemorrhage. Intracranial aneurysms of the ACA are very rare in the early stage of life and their pathogenesis is not clear. This case is of interest as the location and shape of the aneurysm, the absence of relevant familial and medical history, and the histopathological findings raise the hypothesis of a congenital origin. It further describes the value of CT angiography for studying aneurysms in the very young.

Tissue reaction initiated by different sealers.

AIMS: To analyse the type and degree of inflammatory reaction initiated by four sealers. METHODOLOGY: Twenty-four root canals of Macaca mulatta monkeys were filled within the canal and eight were overfilled with AH26, Apexit, Endomethasone or Grossman's sealers. The result of the treatment was evaluated after 6 months by histological assessment of the periapical tissues. RESULTS: In the group of root canals filled within the root, no inflammatory reaction was detected in specimens of Apexit and Grossman's sealers, but the other two sealers initiated different degrees of lymphocytic/plasmocytic tissue reactions. Endomethasone initiated a mild lymphocytic/plasmocytic reaction in three of the nine cases and AH26 caused mild lymphocytic/plasmocytic infiltration in two of the seven cases. In the group of overfilled root canals, all four sealers initiated inflammatory reactions. The periapical tissue reactions of overfilled root canals were similar to reactions detected in cases filled within the canal. However, additional histological features developed in specimens of Endomethasone and AH26: Endomethasone initiated a foreign body-type granulomatous reaction around the sealer particles and AH26 particles were engulfed by macrophages. The overfilled root canals of Apexit and Grossman's sealers initiated only lymphocytic/plasmocytic reactions. CONCLUSIONS: This study suggests that sealers with different chemical compositions initiate different histological reactions. It also emphasizes the importance of confining root filling to the canal system because all sealers initiate inflammatory reactions when they are present in the apical tissues

Resuscitation, anaesthesia and analgesia of the burned patient.

Burns resuscitation has evolved over the past few decades towards more evidence-based management. It has been shown that patients with major burns (i.e. involving more than 30% of the body surface) benefit from invasive monitoring, and physiological variable targeted resuscitation using vasoactive agents for cardiovascular support. The invasive approach results in a reduction of mortality rates. Since the introduction of the Parkland formula in 1968, there has been a trend towards the administration of fluid resuscitation far in excess of the volume predicted with this formula. This has led to an increase in complication rates, with more pulmonary oedema, and the appearance of abdominal compartment syndrome. Hypertonic saline solutions, whether with dextran or not, have shown no advantage over the classic Ringer's lactate solution. The colloid controversy has reached burns resuscitation, with the demonstration that the liberal use of albumin is associated with higher mortality rates. Fresh frozen plasma should only be used for specific coagulation disorders. On the other hand, artificial colloids, particularly gelatine, remain a useful tool in patients with major burns and haemodynamic instability, particularly, and can be given as early as 6 h after injury. Considering the actual evidence, using inotropes and vasopressors to reach supranormal haemodynamic endpoints seems preferable to delivering unrestricted amounts of fluid.

Management of paediatric patients undergoing diagnostic and invasive cardiology procedures.

Since diagnostic cardiac catheterization in children with congenital heart disease was first reported in 1947, echocardiography has been used as a non-invasive diagnostic tool in congenital heart disease, resulting in a decrease in diagnostic cardiac catheterizations. However, the total number of cardiac catheterizations remained at a steady level until the mid-1980s and has since increased progressively. This is a result of the introduction of interventional transcatheter techniques to improve or correct congenital heart malformations. Since the first description of balloon atrial septostomy, the range of indications for such techniques has steadily increased, particularly in the past 15 years. 'Deep' sedation or general anaesthesia is essential for the conduct of cardiac catheterization in children, particularly in the younger age group.

A comparative study of seven instruments in shaping the root canal in vitro.

The objective of this study was to evaluate the shaping characteristics of various root canal instruments using human teeth. A total of 420 extracted human roots were embedded in resin blocks. The embedded roots were divided into three groups, i.e. roots with (i) straight, (ii) apically curved, and (iii) whole-length curved canals according to the Schneider's angle and the length of the radius of arc fitting the curvature of root canals. Each of the three groups containing 140 roots were randomly divided into seven subgroups prior to preparation. The canals were prepared manually with traditional and flexible instruments, engine driven Racer-type, Giro-type, randomly vibrating instruments and with sonic and ultrasonic instruments. The shortcomings of the seven preparation methods were assessed by the superimposition of projected radiographs taken in bucco-lingual and mesio-distal views before and after the preparation. The prepared straight canals showed a high percentage (75.7%) of apical asymmetry. Coronal transposition of the apical stop was graded with higher scores in all canal forms prepared with Racer-type and Giro-type instruments, which could have occurred through packing of debris towards the apical constriction. The majority of the prepared curved canals were asymmetrical in shape. The location of the aberrations depended on the original shape of the canal but the method of shaping also had a decisive effect on the post-operative form of the canal. Large differences were found between the incidence of elbow (11.7-40.0%) and zip (75.7-80.0%). K-Flex files produced minor canal aberrations and significantly less asymmetry (P < 0.05) than the conventional hand instruments. The MM 1400 handpiece and ultrasonic instruments were associated with less aberration and significantly less asymmetry than the other instruments tested. The Excalibur appeared to be superior to the conventional hand instruments in straight canals, but its shaping characteristics were similar to conventional instruments in curved canals. Under the conditions of this study, canal shaping with Cavi Endo, MM 1400 and K-Flex files appeared to be superior to that achieved with conventional hand instruments Excalibur, Intra Lux Endo Kopf 3LDSY, and 3LD instruments.

The effect of root canal morphology on canal shape following instrumentation using different techniques.

The objective of this study was to evaluate the shaping characteristics of different root canal instruments in teeth with different root canal forms. A total of 420 extracted human roots were embedded in resin blocks. The embedded roots were divided into three groups, i.e., roots with (i) straight (I form), (ii) apically curved (J form), and (iii) entirely curved canals (C form) with reference to the Schneider's angle and the length of the radius of arc of the curvature of the root canals. Each of the three groups containing 140 roots were randomly divided into seven subgroups prior to preparation. The canals were enlarged manually with traditional and flexible hand instruments, three different engine driven instruments and sonically and ultrasonically powered instruments. The shortcomings of the seven preparation methods were assessed by superimposition of projected radiographs taken in bucco-lingual and mesio-distal views before and after preparation. Results showed that observation of perforation, incidence of elbow and of asymmetrical preparation of the root canals depended on root canal configuration. It was striking that the coronal transposition of the apical stop, uneven wall contour, ledge formation and incidence of zip were independent of root canal morphology. Evaluation of data of asymmetry of preparation (canal transposition) revealed significant differences (p < 0.05). Asymmetry of preparation was the most frequent aberration of the prepared root canals and it was possible to study it with precision. It was concluded that this measurement should be a priority for future instrument testing. The shaping characteristics of hand and engine driven instruments was modified by root canal morphology, but that of sonic and ultrasonic instruments was less dependent on the original anatomical form of root canals.

Tracheal gas insufflation reduces requirements for mechanical ventilation in a rabbit model of respiratory distress syndrome.

Tracheal gas insufflation is known to lower PaCO2 in larger animal models of respiratory distress syndrome, but its ability to reduce the ventilator pressures and tidal volume needed to achieve an acceptable PaCO2 has not been examined in small animals using modes of ventilation employed in neonatal intensive care. In this study, the effect of insufflating humidified gas into the lower trachea was examined in a saline lung lavage model of respiratory distress syndrome in rabbits, while the peak airway pressure during conventional pressure-limited ventilation was adjusted to keep the PaCO2 approximately constant. Tracheal gas insufflation significantly reduced the peak airway pressure required and reduced the delivered tidal volume but did not affect the AaDO2. The effects were more marked at a ventilator rate of 30 breaths per minute than at 60 bpm and more during continuous insufflation than when gas was insufflated only during expiration. These results suggest that tracheal gas insufflation may reduce the risk of ventilation-induced lung disease in the newborn.

[Comparative evaluation of different instruments for root canal preparation tested on extracted human teeth III. Study of sonic and ultrasonic instruments]. / A gyökércsatorna-tágító müszerek összehasonlító értékelése kihúzott emberi fogakon III. rész. A hangfrekvenciás és az ultrahangmüszerek vizsgálata.

A total of 460 roots of extracted human teeth were divided into three groups i.e. straight, apically curved and entirely curved groups. Each of the three groups were divided into seven subgroups according to instrumentation by conventional hand, K-Flex file, 3-LD, 3-LDSY, Excalibur. MM 1400 and Endo Sonic. Radiographs were taken both clinical and proximal views before and after the enlargement of canals. An assessment of shaping characteristic of instrumentation was made on the basis of overimposed radiographs including perforation, ledge formation smoothness of wall contour incidence of elbow and zip measurements at the elbow level and asymmetry measurements. The majority of enlarged root canals were asymmetrical in shape. High differences were found between the incidence of elbow and zip formation. Under laboratory conditions the K-Flex file produced minor canal aberrations and significantly less asymmetry than the conventional instruments. But both the above mentioned instruments caused perforations on curved canals, such as the instrumentation by Excalibur. The loss of working distance was significant in all canal forms prepared with 3-LD and 3-LDSY instruments, which could have occurred through the packing of debris towards the apical constriction. The Excalibur appeared to be superior to the conventional hand instrument in straight canals, but its shaping characteristic was similar to conventional hand instrument in curved canals. The MM 1400 handpiece and ultrasonic instruments resulted in less aberration and significantly less asymmetry than the other tested instruments.

[In vitro comparative study of instruments for root canal preparation. IV. Correlations between the original shape of the root canal and the asymmetry resulting from the preparation]. / Gyökércsatorna-preparáló müszerek in vitro összehasonlító vizsgálata. IV. rész. A gyökércsatorna eredeti formája és a preparálás során keletkezö aszimmetriák összefüggései.

Certain asymmetry of root canal preparation can be observed in the straight root canal group, as well. The modification of original root canal shape in this group usually is not substantial. Using hand instruments for shaping curved canals special tecniques are required to minimize the asymmetry. Though tendencies of different shaping characteristics can be observed on the mesiodistal and oro-vestibular views there are no statistically significant differences between the asymmetries measured on the oro-vestibular and mesio-distal views. The three dimensional form of canals usually exclude the possibility of forming the same asymmetry on both projections, but the difference between the two views is not striking, therefore the conventional clinical radiographs usually do not give complete information about the asymmetry of preparation.

[In vitro comparison of instruments for root canal preparation. III. Study of the instruments from the viewpoint of shaping asymmetry]. / Gyökércsatorna-preparáló müszerek in vitro összehasonlító vizsgálata. III. rész. A preparálóeszközök vizsgálata a tágítás aszimmetriájának szempontjából.

The shape of the prepared root canals is not consistent with the original anatomical shape in the majority of curved canals. The discrepancy is dependent of the type of instrument, the original anatomical form of the root canal and the location of the measurement. The original shape of the root canal has to be taken into consideration in the selection of preparatory instruments because their application is limited by the above mentioned factor. The sonic and ultrasonic preparatory instruments form an exception in this respect due to their non aggressive way of shaping. These instruments cannot be disregarded in the preparation of curved root canals.

[In vitro comparison of instruments used for root canal preparation. II. Effectiveness of the instruments]. / Gyökércsatorna-preparáló müszerek in vitro összehasonlító vizsgálata. II. rész. A müszerek hatékonyságának vizsgálata.

According to our examination, the anatomical shape of the root canal can influence the function of the examined instrument, therefore it's advisable to pay attention to the canal's curve at the selection of the root canal cutting instrument. Concerning the examined instruments, the least effective was the ultrasonic instrument.

[In vitro comparison of instruments for root canal preparation. I. Pilot study of the homogeneity of study groups]. / Gyökércsatorna-preparáló müszerek in vitro összehasonlító vizsgálata. I. Rész. Elökísérlet a kísérleti csoportok homogenitásának vizsgálatára.

If extracted human teeth are used for comparative study of root canal preparatory instruments the selection of roots into homogeneous test groups is decisive step of the experiment. On the basis our pilot USDA it is necessary not only to consider the Schneider angle and the length of root canal curvature but the surface area of root canals on the mesio-distal and oro-vestibular radiographs showing the projected view of the canals.

[Comparison of the planimetric and gravimetric methods in the study of the efficiency of endodontic instruments]. / Az endodontiai eszközök hatékonyságának vizsgálatára szolgáló plani- és a gravimetriás módszer összehasonlítása.

Both gravimetry (measurement of weight loss of roots after root canal preparation) and planimetry (measurement of surface area corresponding to the removed dentin layer of canal walls on oro-vestibular and mesio-distal X-ray views of roots before and after the preparation) were used on the same samples for determination of the efficacy of root canal shaping instruments. There were no statistically significant differences between the results obtained using either the gravimetry or the planimetry indicating the evidence of reliability of results obtained using only the planimetry as a single method.