bluuebunny/crossref_metadata_2025_split huggingface dataset:
Treatment of root perforations with calcium hydroxide and SuperEBA cement: a clinical report
Authors: BOGAERTS P. 
Published: November 2003

SummaryIatrogenic root perforations sometimes occur during root canal treatment or when preparing the root canal for a post. The inflammation in the periradicular tissues caused by root perforation reduces the prognosis of the involved tooth. The situation may be further complicated if by coronal leakage, microorganisms are allowed to infect the canal and the periradicular region. This clinical report presents a nonsurgical technique, based on the internal matrix concept, using both calcium hydroxide and SuperEBA together to repair root perforations. The author has experienced good clinical results with this perforation repair technique.
Comparison of two laser Doppler systems on the measurement of blood flow of premolar teeth under different pulpal conditions
Authors: MESAROS S. , TROPE M. , MAIXNER W. , BURKES E. J. 
Published: November 2003

SummaryAn in vivo investigation was conducted to assess the ability of two laser Doppler flowmeters (DRT4, Moor Instruments Ltd; Laserflo BPM2, Vasamedics) to differentiate between vital pulp, ischaemically necrosed pulp, and an empty pulp chamber in premolar teeth in children. Sixteen intact, vital teeth in need of extraction for orthodontic purposes were identified. Laser Doppler blood flow readings were taken prior to (Tl) and after the administration of adrenaline‐free local anaesthetic (T2), after extraction and replantation of the teeth (T3), and after broaching the pulp tissue and replanting the teeth (T4). The data collected (flux values) far both instruments were analysed using a repeated measures ANOVA. Significant differences were found for vital pulp (Tl, T2) versus ischaemically necrosed pulp (T3), and for vital pulp (Tl, T2) versus an empty pulp chamber (T4), with the Moor DRT4 instrument This instrument also detected a significant difference in pulpal blood flow to the vital pulp, before and after the administration of local anaesthetic. No other significant differences were found.
Periapical radiographic techniques during endodontic diagnosis and treatment
Authors: FAVA L. R. G. , DUMMER P. M. H. 
Published: November 2003

SummaryThe objective of this article is to describe various radiographic projections which can be used during endodontic therapy. Changes to the angulation of the X‐ray beam in relation to the teeth and film can help diagnosis and treatment by producing images which provide additional information not always visible on radiographs taken with standard angulations. For example, changes in angulation can be useful to determine the number and curvature of roots and canals, to identify superimposed roots and to distinguish between anatomical landmarks and apical pathology. Although use of such techniques increases the diagnostic yield of films, it must be appreciated that such views lead to images that are less distinct because of inherent image distortion. Nevertheless, use of the various techniques during endodontics can provide substantial benefit for clinicians In their daily practice.
Effect of sealer thickness on long–term sealing ability: a 2–year follow–up study
Authors: KONTAKIOTIS E.G. , WU M‐K. , WESSELINK P.R. 
Published: November 2003

SummaryLong‐term sealing ability of root‐canal sealer is of clinical importance. We compared the performance of five sealers and a dentine bonding agent, at thicknesses of 0.05 mm (thin layer) and 0.3 mm (thick layer), in 212 standard human root specimens, before and after storage in water for 2 years. Thick layers of Roth and Pulp Canal Sealer EWT (PCS–EWT) allowed more leakage than did thin layers (P = 0.0000, 0.0358 for Roth and PCS–EWT, respectively) whereas no significant difference was found between the thin and thick layers for AH26, Ketac‐Endo, Sealapex and J& J Bonding Agent. The pooled results of the thin and thick layers, which have clinical relevance, showed that after storing the specimens in water for 2 years, AH26, Sealapex, Ketac‐Endo and PCS–EWT leaked more than before storage in water (P = 0.0008, 0.0000, 0.0035, 0.0257 for AH26, Sealapex, Ketac‐Endo and PCS–EWT respectively), and that)&J Bonding Agent allowed less leakage and PCS‐EWT more leakage than the other four sealers (P= 0.0000).
Scanning electron microscope study comparing four root canal preparation techniques in small curved canals
Authors: HEARD F. , WALTON R.E. 
Published: November 2003

SummaryVarious instrumentation techniques have been proposed and examined with conflicting results. They include hand and ultrasonic techniques and combinations of the two. In the present study we assesed the effectiveness of four preparation methods for cleaning small, curved root canals, using backscattered‐imaging scanning electron microscopy (SEM). The methods were: (i) step‐back without initial coronal flaring; (ii) step‐back with coronal flaring; (iii) step‐back with initial coronal flaring and finished by ultrasonic irrigation; and (iv) ultrasonics only.Eighty freshly extracted maxillary and mandibular molars were randomly placed into four treatment groups of 20 teeth each. After preparation, roots were sectioned longitudinally and examined wet by SEM. Each canal was qualitatively evaluated and the groups compared for removal of debris and smear layer, both overall and at each level (apical, middle and coronal).There were no statistically significant differences between the techniques, either overall or within any of the regions. When comparing regions (regardless of technique) the middle level was cleaner than the apical or coronal levels.In conclusion, efficacy differed little among the techniques; none of them completely removed smear layer and all left debris.
Influence of infection at the time of root filling on the outcome of endodontic treatment of teeth with apical periodontitis
Authors: SJÖGREN U. , FIGDOR D. , PERSSON S. , SUNDQVIST G. 
Published: November 2003

SummaryThis study investigated the role of infection on the prognosis of endodontic therapy by following‐up teeth that had had their canals cleaned and obturated during a single appointment. The root canals of 55 single‐rooted teeth with apical periodontitis were thoroughly instrumented and irrigated with sodium hypochlorite solution. Using advanced anaerobic bacteriological techniques, post–instrumentation samples were taken and the teeth were then root‐filled during the same appointment. All teeth were initially infected; after instrumentation low numbers of bacteria were detected in 22 of 55 root canals. Periapical healing was followed up for 5 years. Complete periapical healing occurred in 94% of cases that yielded a negative culture. Where the samples were positive prior to root filling, the success rate of treatment was just 68%– a statistically significant difference. Further investigation of three failures revealed the presence of Actinomyces species in each case; no other specific bacteria were implicated in failure cases. These findings emphasize the importance of completely eliminating bacteria from the root canal system before obturation. This objective cannot be reliably achieved in a one‐visit treatment because it is not possible to eradicate all infection from the root canal without the support of an inter–appointment antimicrobial dressing.
Observation of Saccharomyces cerevisiae in blood of patient undergoing root canal treatment
Authors: DEBELIAN G. J. , OLSEN I. , TRONSTAD L. 
Published: November 2003

SummaryIn this study, an unusual observation of Saccharomyces cerevisiae isolated from an infected root canal and from the blood of a patient undergoing endodontic therapy of a tooth with asymptomatic apical periodontitis is reported. Phenotypic (biochemical tests, antifungal susceptibility tests and SDS‐PAGE of cellular proteins) and genetic (ribotyping) methods were used to characterize the strains. By using these methods it was found that the blood and root canal isolates were identical but differed from S. cerevisiae strains of other sources. It was therefore more than likely that the root canal was the source of the blood isolate and that it had been transferred unintentionally to the bloodstream during root canal treatment.
Analysis of forces developed during root canal preparation with the balanced force technique
Authors: BLUM J.‐ Y. , MACHTOU P. , ESBER S. , MICALLEF J. P. 
Published: November 2003

SummaryThe aim of this study was to examine the forces and torque developed during root canal preparation with the balanced force technique using a recently described force‐analyser device. A tooth was placed in a holder within the Endograph and forces and torques exerted were recorded. These parameters, which can be studied during preparation (on‐line) or stored and examinated subsequently (off‐line) generated endograms, which showed the forces generated with time. In addition, the endograms of preparations performed by students and endodontists, as well as deliberately induced failures in preparation technique (broken instruments), were compared. The values for the forces and torques depended on the size of the instruments and were related to the phase of the preparation. For the endodontists, the vertical and horizontal forces varied, respectively, from 0.08 ±0.01 kg for a size 15 to 0.65 ±0.10 kg for a size 45, and from 0.01 ±0.005 kg for a size 15 to 0.4±0.1 kg for a size 40. The torque varied from 0.08 ± 1 kg mm‐1 for a size 15 to 1.6 ± 0.4 kg mm‐1 for a size 45. With the Endograms used as a reference, the relation between the developed vertical forces and the torque became more similar between the groups of endodontists and students. The Endograph provides a new approach to the analysis of preparation technique because it depicts the relationships between the different parameters of the preparation.
Identification and characterization of antioxidant enzyme mRNAs in the rat epididymis
Authors: ZINI A. , SCHLEGEL P. N. 
Published: November 2003

Spermatozoa are highly sensitive to oxidative stress. The epididymis, a natural sperm reservoir, has maturational and storage functions. The epididymis may also protect spermatozoa from oxidative injury by elaborating scavengers of reactive oxygen species (ROS). Therefore, we have evaluated the mRNA expression of antioxidant enzymes in the normal rat epididymis and the effects of efferent duct ligation on the expression of these enzymes.Adult rat epididymides were harvested, divided into caput, corpus and cauda and processed for RNA extraction. Additional adult rats were subjected to unilateral efferent duct ligation and the epididymides harvested at 1, 4, 8, 16 or 28 days after the procedure. Antioxidant enzyme mRNA expression was assessed by Northern blot analysis using 32P‐labelled DNA probes derived from known cDNA sequences for classical cellular glutathione peroxidase (GSHPx), phospholipid hydroperoxide glutathione peroxidase (PHGPX), secretory epididymal glutathione peroxidase (E‐GPX), copper‐zinc superoxide dismutase (SOD), secretory epididymal superoxide dismutase (E‐SOD) and catalase. Specific mRNA levels were measured, with gene expression evaluated relative to total RNA, not per organ. Variations in lane loading were controlled by measuring the levels of 28S ribosomal RNA.GSHPx, PHGPX, SOD and catalase mRNA were detected in the caput, corpus and cauda epididymis. E‐GPX mRNA was only detected in the caput, whereas E‐SOD mRNA was primarily detected in the corpus. At 28 days after efferent duct ligation, epididymal weight decreased by 34% relative to controls ( p <  0.05). With the exception of PHGPX, the relative mRNA levels of the antioxidant enzymes studied did not change after efferent duct ligation.This study demonstrates that mRNAs for multiple antioxidant enzymes are expressed in the epididymis and that the relative expression of these enzymes remains largely unchanged in response to efferent duct ligation. Taken together, these results suggest that antioxidant enzymes may play an important, region‐specific role in epididymal function. Expression of the secretory antioxidant enzymes E‐SOD and E‐GPX is region‐specific, indicating that the need for antioxidant enzymes may vary along the length of the epididymis.
Histochemical demonstration of zinc ions in ejaculated human semen
Authors: STOLTENBERG M. , SØRENSEN M. B. , DANSCHER G. 
Published: November 2003

A revised in‐vitro technique for autometallographic demonstration of chelatable zinc in the human ejaculate is presented, and the localization of the loosely bound pool of zinc ions is described in semen smears and at the ultrastructural level. In semen smears, black autometallographic (AMG) grains indicated the presence of zinc ions dispersed between the spermatozoa. These AMG grains have the same size as grains associated with the sperm tail and may have the same origin. EM analysis of AMG‐developed smears fixed in osmium suggested that the detected zinc ions might be related to huge protein molecules present in semen and adhering to the surface of the spermatozoa.Spermatozoa in AMG‐stained smears exhibited zinc ions in the midpiece and head, and also joined to the membrane of the tail. Washed spermatozoa exhibited zinc ions only within the midpiece. Ultrastructurally, they were found located in the helecine mitochondria. A few grains were found in the acrosome of the washed spermatozoa. Treatment with the chelating agent DEDTC resulted in complete bleaching of the zinc staining. These findings and the fact that calcium EDTA acid blocks the plasma and surface staining, but not the acrosomal and mitochondrial staining, suggest that chelatable zinc ions exist in two separate pools in human semen.
Histopathological changes in Yucatan minipig skin following challenge with sulphur mustard. A sequential study of the first 24 hours following challenge
Authors: BROWN R.F.R. , RICE P. 
Published: November 2003

Sulphur mustard (HD) or ‘mustard gas’ is a potent vesicant chemical warfare agent whose biological effects in man have been well documented. The histopathological features of the developing cutaneous HD lesion in female Yucatan minipigs up to 24 hours post exposure are reported. Following challenge with HD vapour at a concentration of 12.0 μmol/cm2 a sequence of ultrastructural changes to keratinocytes occurred which were initially seen in the stratum basale. Condensation of nuclear heterochromatin and loss of euchromatin was accompanied by cytoplasmic swelling and culminated in focal epidermal necrosis which was evident at 24 h after the challenge.The melanocyte appeared to be the cell type most sensitive to HD challenge with a loss of cytoplasmic electron density in areas of the cytoplasm immediately surrounding the melanosomes, chromatin condensation, nuclear membrane blebbing with mitochondrial and generalized cytoplasmic swelling. Isolated complete cell necrosis and disruption were noted as early as 2 h following the challenge with generalized necrosis being seen from 12 h onwards. From 12 h onwards, areas of basement membrane degeneration were also observed. These appeared similar in ultrastructure to that observed in other animal model systems but did not progress to the large blisters so typical of the human lesion.Damage to the upper dermis took the form of an inflammatory response typified by vascular endothelial swelling and vacuolation, dermal oedema and inflammatory cell (mainly neutrophil) infiltration.There was some evidence of transitory epidermal damage outside the prescribed wound area. This finding may be of clinical importance when surgical treatments are being considered.
The family interview: exploring experiences of family health and well‐being
Authors: Åstedt‐Kurki Pävi , Hopia Hanna 
Published: November 2003

Health and well‐being are basic concepts to nursing science and also important to practical nursing care to provide effective nursing we need to have a good understanding of both health and well‐being Experienced health has been studied quite extensively at the individual level, but the family's point of view has been very much neglectedThis study collected data on families' views on health and well‐being in interviews with nine families The interviews were held in a group situation, with all family members present, and they were structured around the three core themes identified by Åstedt‐kurki in her doctoral dissertation ‘doing, knowing, feeling’ The emotional bonds that the together family members may be a factor in the family's tendency to produce rich and detailed knowledge about their well‐being in interview situations On the other hand it is also possible that the family will try to convey as positive and image of itself as possible For reasons of reliability the nine families taking part in this study were interviewed twice
Pharmacological characterization of adrenoceptors in horse corpus cavernosum penis
Authors: Recio P. , López P. G. , Fernández J. L. G. , García‐Sacristán A. 
Published: November 2003

1 The presence and types of α and β‐adrenoceptors in the corpus cavernosum of the horse were studied in vitro by using selected ligands of adrenoceptors and isometric tension recording. 2 Noradrenaline and phenylephrine induced concentration‐dependent contractions in corpus cavernosum preparations. B‐HT 920 had no effect. 3 Phentolamine and prazosin produced a shift to the right of the dose‐response curve of noradrenaline, while the α2‐antagonist, rauwolscine had no effect on the response to noradrenaline. Phenylephrine‐evoked contractions of corporal strips were significantly inhibited by the α1‐adrenoceptor antagonist, prazosin. 4 Isoprenaline and salbutamol each relaxed precontracted corpus cavernosum preparations in a concentration‐dependent manner; the isoprenaline effect was blocked by propranolol, practolol and butoxamine. The salbutamol effect was blocked by butoxamine. 5 These results suggest the presence of postjunctional α1‐adrenoceptors in horse corpus cavernosum. There is also a heterogenous population of β‐adrenoceptors in this tissue, belonging to the β1 and β2 subtypes.
Prevention by a somatostatin analogue of the hypertensive and cardiovascular structural changes induced by blockade of adenosine receptors
Authors: Calhau C. , Martel F. , Alçada M.N.M.P. , Azevedo I. 
Published: November 2003

1 Long‐term administration of the adenosine receptor antagonist, 1,3‐dipropyl‐8‐sulfophenylxanthine (DPSPX), causes arterial hypertension and cardiovascular hypertrophic and hyperplastic changes (Matias, Albino‐Teixeira, Polónia & Azevedo, 1991). As somatostatin is a repressor of cell growth, and adenosine is a potent inducer of the somatostatin gene, we investigated the putative involvement of somatostatin in the cardiovascular effects of DPSPX. 2 DPSPX (90 μg kg−1 h−1, i.p.) or saline and the somatostatin analogue, octreotide (75 μg kg−1 day−1, s.c.), or saline were infused through Alzet minipumps to Wistar rats. Blood pressure was measured with the tail‐cuff technique. Seven days after implantation of the minipumps the rats were killed and the tissues prepared for microscopy. 3 DPSPX induced arterial hypertension and cardiovascular hypertrophic and hyperplastic changes as previously described (Matias et al., 1991). Treatment of the rats with octreotide alone had no effect either on blood pressure or in blood vessel morphology. However, octreotide prevented both the hypertensive and the cardiovascular morphologic effects of DPSPX. 4 The results are compatible with the involvement of somatostatin in the long‐term cardiovascular effects of adenosine.
Water‐soluble fullerene derivatives attenuate exsanguination‐induced bronchoconstriction of guinea‐pigs
Authors: Lai Y.‐L. , Chiang L. Y. 
Published: November 2003

1 This study investigated the effects of increased antioxidants (administration of water‐soluble fullerenol‐1 and pre‐exposure to chronic hypoxia) as well as an iron‐chelating agent (deferoxamine) on exsanguination‐induced noncholinergic airway constriction in guinea‐pigs. 2 Fullerenol‐1 usually did not cause significant alteration in respiratory function (lung volumes, dynamic respiratory compliance, maximal expiratory flow at 50% total lung capacity (V¨max50), and forced expiratory flow at 0.1 s (FEV0.1)) at low (200 μg kg−1) or at high doses (2 mg kg−1), except that it produced a slight bronchial constricting action (decreases in both V¨max50 and FEV0.1) at high doses (2 mg kg−1) via intratracheal instillation. 3 Beginning 15 min after exsanguination, there was a marked temporal decrease in FEV0.1, indicating a gradual increase in airway constriction with time. 4 Administration of either fullerenol‐1 or deferoxamine, or pre‐exposure to chronic hypoxia significantly ameliorated the exsanguination‐induced bronchoconstriction. The results provide evidence that oxygen radicals play an important role in exsanguination‐induced airway constriction. 5 The significant effects of the increased antioxidants and deferoxamine, however, cannot be explained by the alteration in either tracheal neutral endopeptidase activity or lung tissue substance P level.
Comparative effects of calcium channel blockers and indomethacin on insulin secretion and blood pressure increase derived from α1‐adrenoceptor stimulation in the rabbit
Authors: García‐Barrado M. J. , Reverte M. , Palomero J. , Moratinos J. 
Published: November 2003

1 In conscious, fasted rabbits the intravenous infusion of the α1‐adrenoceptor agonist, amidephrine (3 and 10 μg kg−1 min−1) induced a dose related increase in insulin plasma levels. This effect was accompanied by a minor hypo‐ or hyperglycaemic response, depending on the dose of agonist infused. 2 A dose related increase in mean arterial pressure and reduction in heart rate were also found after amidephrine administration. 3 The insulin secretory response to amidephrine was not prevented in rabbits previously treated with atropine (5.26 μg kg−1 min−1). However, in the presence of muscarinic receptor blockade the bradycardic effect of amidephrine was either suppressed or attenuated. 4 Pretreatment with the calcium channel antagonist elgodipine (35 ng kg−1 min−1) or with indomethacin (0.66 mg kg−1 min−1) clearly blocked the effect of amidephrine on insulin secretion. 5 The haemodynamic changes induced by amidephrine were preserved in the presence of either verapamil (0.17 μg kg−1 min−1) or indomethacin, whereas the hypertensive response was antagonized by elgodipine. 6 Our results suggest that the metabolic and haemodynamic changes mediated by amidephrine are two independent effects, insulin secretion requiring the presence of extracellular calcium and the synthesis of arachidonic acid metabolites.