bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microleakage of Diaket and amalgam in root‐end cavities prepared using MicroMega sonic retro‐prep tips
Authors: LLOYD A. , GUTMANN J. , DUMMER P. , NEWCOMBE R. 
Published: November 2003

SummaryThein vitro sealing ability of the root‐canal sealer Diaket when used as a root‐end filling material was compared with that of amalgam using linear microleakage of Indian ink. Eight groups of 20 extracted teeth each were formed, plus 12 control teeth as follows: 1) root‐end resection of 45° bevel, root‐end cavity preparation with an 008 round bur, amalgam root‐end filling; 2) 45° bevel, bur, Diaket; 3) 45° bevel, using a sonic retro‐prep tip, amalgam; 4) 45° bevel, sonic, Diaket; 5) no bevel, bur, amalgam; 6) no bevel, bur, Diaket; 7) no bevel, sonic, amalgam; 8) no bevel, sonic, Diaket, Root‐end cavity depths of 3 mm were prepared. Specimens were immersed in Indian ink for 2 weeks. The teeth were demineralized, rendered transparent and linear dye penetration recorded. Results showed that Diaket provided a superior seal to amalgam irrespective of the root‐end preparation. The degree of bevel of the resected root‐end did not influence leakage. Sonic instrumentation resulted in a larger root‐end cavity than with burs.
Calcium hydroxide root canal sealers: evaluation of pH, calcium ion concentration and conductivity
Authors: da SILVA L. A. BEZERRA , LEONARDO M. R. , da SILVA R. S. , ASSED S. , GUIMARÃES L. F. L. 
Published: November 2003

SummaryThe calcium hydroxide ionization of four root canal sealers (Sealapex, CRCS, Sealer 26, and Apexit) was studied by measuring conductivity and pH and by conducting atomic absorption spectroptiotometry. Samples 6 mm in diameter and 15 mm long were prepared from these sealers. After setting and 48 h storage in a desiccator, five samples of each material were placed in 50 ml distilled water and analysed after 0,1,2,4, 6 and 24 h and 5, 15 and 30 days. The results showed that Sealapex was the root canal sealer showing the highest pH, ionic calcium and total calcium values (P<0.05) throughout the experimental period, followed by CRCS, Apexit and Sealer 26
Root canal treatment of a mandibular canine with three root canals. Case report
Authors: HOLTZMAN LIOR 
Published: November 2003

SummaryThe differing morphological manifestations of the root canal system have been the subject of research, and the incidence of various shapes of root canal systems has been classified. The present case describes the root canal treatment of a rare morphological pattern, namely a mandibular permanent canine with three root canals. No report of a similar case has been published previously.
Cutaneous odontogenic sinus tract to the chin: a case report
Authors: TIDWELL E. , JENKINS J.D. , ELLIS C.D. , HUTSON B. , CEDERBERG R.A. 
Published: November 2003

SummaryWe report a case of cutaneous odontogenic sinus tract to the chin. The patient first noticed the cutaneous condition in 1977. Inappropriate medical and dental treatment was ineffective. Correct diagnosis and treatment was completed in 1993. We offer diagnostic and treatment guidelines for the management of similar cases.
Sealing properties of a new epoxy resin‐based root‐canal sealer
Authors: ZMENER O. , SPIELBERG C. , LAMBERGHINI F. , RUCCI M. 
Published: November 2003

SummaryIn this study a new epoxy‐resin‐based endodontic sealer, AH Plus, was tested in vitro for apical leakage. The conventional sealer AH26, for which information is already available, was used as the control. The root canals of 72 single‐rooted teeth were prepared biome‐chanically using a stepback technique before lateral condensation of gutta‐percha with one of the two sealers. Teeth were immersed in 5% methylene blue dye for 2,4 or 10 days. The roots were split longitudinally so that the extent of dye penetration could be measured with a stereomicroscope. The mean extent at 2 days was 0.4 mm for AH26 and 1.4 mm for AH Plus. Neither material produced a complete apical seal and leakage increased with the duration of immersion in dye. The differences between observation periods as well as between materials with respect to dye penetration were statistically significant ANOVA, (P < 0.005).
An evaluation of microbial coronal leakage in the restored pulp chamber of root‐canal treated multirooted teeth
Authors: CHAILERTVANITKUL P. , SAUNDERS W. P. , SAUNDERS E. M. , MACKENZIE D. 
Published: November 2003

SummaryThis in vitro study investigated the effect of a resinreinforced glass ionomer lining material on the coronal leakage of a mixed obligate microbial marker in maxillary molars obturated with lateral condensation of cold gutta‐percha and Tubliseal sealer, after 2 years' storage. Forty maxillary first molars were prepared chemomechanically to a size 30–40 master apical file. The teeth were divided into an experimental group (30 teeth) and control group (10 teeth). In the experimental group, the floor of pulp chamber and the root‐canal opening of I5 teeth were covered with Vitrebond as a lining; the remaining 15 teeth received no lining. These teeth were tested for leakage using a microbiological marker consisting of anaerobic streptococci and Fusobacterium nucleatum. The teeth were checked daily for bacterial leakage for 60 days. All positive control teeth leaked within 48 h, while the negative control teeth remained uncontaminated throughout the test period. The teeth restored with Vitrebond liner showed no leakage whilst 60% of the specimens with no Vitrebond liner showed leakage after 60 days.
An in vitro study of coronal microleakage in root‐canal‐treated teeth restored by the post and core technique
Authors: FOX K. , GUTTERIDGE D. L. 
Published: November 2003

SummaryThe aims of this study were to compare coronal microleakage around cast and prefabricated post and cores and to examine the coronal seal achieved by temporary post crowns. Thirty extracted, single‐rooted, human teeth were prepared chemomechanically, root filled with gutta‐percha and sealer and prepared for a standard post. Three groups, each of 10 teeth, were restored with either: (i) cast post and cores cemented with zinc phosphate cement; (ii) prefabricated posts and composite cores cemented with a composite luting cement; or (iii) temporary post crowns cemented with a temporary zinc oxide–eugenol cement. The teeth were thermocycled and placed in Indian ink for 1 week, then demineralized and rendered transparent. Linear coronal dye penetration around the posts was measured and recorded. Results indicated that while cast post and cores and prefabricated posts and composite cores produced a good seal, leakage was significantly greater with temporary post crowns (P < 0.05). It is concluded that to prevent re‐infection of the root canal system, it may be preferable to restore the tooth immediately with a prefabricated post and composite system rather than place a temporary post crown and subsequently a cast post and core.
Evaluation of the effectiveness of sodium hypochlorite used with three irrigation methods in the elimination of Enterococcus faecalis from the root canal,in vitro
Authors: SIQUEIRA J.F. , MACHADO A.G. , SILVEIRA R.M. , LOPES H.P. , de UZEDA M. 
Published: November 2003

SummaryThe effectiveness of 4.0% sodium hypochlorite (NaOCl) used with three irrigation methods in the elimination ofEnterococcus faecalis from the root canal was tested in vitro. Root canals contaminated with E.faecalis were treated as follows: (i) irrigation with 2 mL of NaOCl solution and agitation with hand files;(ii)irrigation with 2 mL of NaOCl solution and ultrasonic agitation;(iii)irrigation with NaOCl alternated with hydrogen peroxide. Contaminated canals irrigated with sterile saline solution served as the control. Paper points used to sample bacteria from the root canals were transferred to tubes containing 5 mL of brain heart infusion (BHI) broth. Tubes were incubated and the appearance of broth turbidity was indicative of bacteria remaining in the root canal. There were no statistically significant differences between the experimental groups. However, NaOCl applied by the three methods tested, was significantly more effective than the saline solution(control group) in disinfecting the root canal.
Bacterial penetration through temporary restorative materials in root‐canal‐treated teeth in vitro
Authors: IMURA N. , OTANI S. M. , CAMPOS M. J. A. , JARDIM E. G. , ZUOLO M. L. 
Published: November 2003

SummarySeventy extracted single‐rooted mandibular premolars were used in this study to determine the length of time needed for bacteria present in natural human saliva to penetrate through three commonly used temporary restorative materials and through the entire root canal system obturated with the lateral condensation technique. Five intact teeth with no decay were used in the negative control group and five teeth with extensive decay in communication with the canal, in the positive control group. The 60 teeth used in the experimental group were divided into three groups. In Group 1, the access cavities of 20 teeth were temporarily restored with gutta percha, in Group 2 with IRM and in Group 3 with Cavit‐G. All 70 teeth were mounted individually where the crown was placed in contact with human saliva. All five teeth in the positive control group caused broth turbidity within 24 h. In contrast, broth in the negative control group remained clear throughout the entire experimental period. In the experimental group, the average time for broth contamination of access cavities closed with gutta percha, IRM and Cavit‐G was 7.85, 12.95 and 9.80 days, respectively. The Kruskal‐Wallis nonparametric test showed significant differences among the groups, while the multiple comparison test showed that the IRM group was statistically better than the gutta percha group when the average lengths of time for contamination were compared (P < 0.05).
Antibacterial activity of calcium hydroxide‐containing endodontic sealers onEnterococcus faecalis in vitro
Authors: FUSS Z. , WEISS E. I. , SHALHAV M. 
Published: November 2003

AbstractAntimicrobial activity of endodontic sealers is an important factor in the prognosis of root canal treatment. The aim of this study was to analyse the antimicrobial activity of calcium hydroxide‐containing endodontic sealers, Sealapex (SA) and CRCS compared to a ZOE‐containing sealer, Roth's cement. The sealers were mixed and placed on the side wall of microtitre plate wells. A 10 μL suspension of Enterococcus faecalis was added to the surface of the sealers 1 h, 24 h, or 7 days after mixture. Bacteria were allowed to come into contact with the sealers for 1 h at 37°. Fresh media was then added and bacterial growth was measured every 30 min for 16 h. The results showed that in 1‐hour‐old mixture, CRCS and Roth's cement had a significantly better antimicrobial effect than SA. In 24‐hour‐old mixtures, ZOE‐based sealer showed a more potent antimicrobial activity than calcium hydroxide‐containing sealers, whereas SA showed a significantly better antimicrobial effect in the 7‐day‐old mixture. The antimicrobial activity of each tested sealer changes differently with the time interval between mixing and testing, suggesting different physicochemical properties and potentially diverse clinical applications.
Does the gonadotrophic axis play a role in the pathogenesis of Sertoli‐cell‐only syndrome?
Authors: LEIFKE E. , SIMONI M. , KAMISCHKE A. , GROMOLL J. , BERGMANN M. , NIESCHLAG E. 
Published: November 2003

Infertile men with Sertoli‐cell‐only syndrome (SCO) have highly elevated serum FSH immunoactivity related to the degree of histological damage. The activity that serum FSH exerts at the target site depends on its glycosylation pattern and FSH receptor (FSHR) function. Either could be impaired, leading to failure of spermatogenesis. The aim of the present investigation was to study bioactivity and the glycosylation pattern of serum FSH and the occurrence of mutations in the FSH receptor in infertile patients with SCO compared to normal men.Blood was taken from 19 patients with bilateral testicular focal or complete SCO and eight normozoospermic controls. FSH bioactivity in serum was measured using an␣ in‐vitro FSH bioassay based on recombinant rat FSHR. The glycosylation pattern of serum FSH was determined by concanavalin A chromatography. Inhibin B was determined in serum using a recently available assay. Genomic DNA extracted from blood lymphocytes was amplified by PCR using primers specific for the FSHR and screened by single‐stranded conformation polymorphism gel electrophoresis.Men with SCO showed significantly higher FSH in‐vitro bioactivity␣(34.9 ± 5.0␣IU/l) than controls (9.6 ± 0.8 IU/l; p < 0.01), as well as significantly elevated FSH immunoactivity (14.9 ± 1.7 IU/l) compared to controls (3.1 ± 0.5; p < 0.01). Immunoactivity of serum FSH was correlated with in‐vitro bioactivity (r = 0.9; p < 0.001) and was related to the degree of testicular damage (proportion of SCO‐tubules) (ANOVA: p < 0.001) and total testicular volume (r = −0.76; p < 0.01). An inverse relationship between serum FSH and inhibin B levels (r = −0.93; p < 0.001) was found. In the serum of SCO patients a slight increase in less glycosylated FSH isoforms was found (6.7 ± 0.6% versus 3.6 ± 0.3%; p < 0.05). No mutations of the FSHR were observed in SCO patients.We conclude that the spermatogenic failure observed in infertile patients with SCO histology and elevated FSH serum levels can be explained neither by a change in FSH bioactivity nor by mutations in the FSHR. The slight change in the FSH glycosylation pattern is probably related to higher hormonal secretion rates in SCO patients. The inverse relationship between serum FSH and inhibin B points to an intact endocrine testicular–pituitary circuit responsible for the compensatory increase of FSH in SCO.
Increased testosterone production in vitro by Leydig cells from rats with severe autoimmune orchitis
Authors: SUESCUN M. O. , CALANDRA R. S. , LUSTIG§ L. 
Published: November 2003

We have previously observed (M. O. Suescun et al., 1994, Journal of Andrology, 15, 442–448) that rats with autoimmune orchitis (EAO) exhibit increased testosterone production in vitro by isolated testes. The aim of the present study was to determine whether the increase in testosterone production correlated with an enhanced number of Leydig cells and/or enhanced steroidogenic capacity per Leydig cell. For this purpose, EAO was induced in adult Sprague‐Dawley rats by active immunization with testicular homogenate and adjuvants. At 80 days after the primary immunization, 60% of rats presented with severe testicular damage characterized by sloughing of the seminiferous epithelium, seminiferous tubule atrophy and interstitial mononuclear cell infiltration. At 160 days after the first immunization, testicular lesions were more severe. A morphometric study, by light microscopy, showed an increase in the number of Leydig cells in rats with EAO (45% increase at 80 days and 50% at 160 days). By electronmicroscopy, testicular sections of rats with EAO revealed the presence of numerous Leydig cells closely associated with macrophages. Most Leydig cells exhibited ultrastructural features of active steroid secreting cells.The steroidogenic capacity of Percoll‐purified Leydig cells from testes of rats with EAO, killed at 80 and 160 days, was evaluated. Leydig cells from rats with EAO exhibited an enhanced steroidogenic response to hCG in vitro at 80 days (38%) and an increase in basal (77%) and post‐hCG testosterone production (115%) at 160 days compared to controls. However, these cells were less sensitive to hCG. In conclusion, the results indicate that the enhancement of in‐vitro testosterone production observed in rats with EAO is accounted for both by the increased number of Leydig cells and by the increased testosterone production of each Leydig cell.
Transforming growth factor‐β production during the development of renal fibrosis in rats with subtotal renal ablation
Authors: COIMBRA T.M. , CARVALHO J. , FATTORI A. , DA SILVA C.G.A. , LACHAT J.J. 
Published: November 2003

The histologic changes observed in the remnant kidney model include progressive mesangial expansion with collapse of capillary lumina, interstitial fibrosis and mononuclear cellular infiltration. Transforming growth factor‐beta (TGF‐β1) is an important regulator of extracellular matrix formation. The purpose of this study was to investigate the production and distribution of TGF‐β1 in the kidney during the development of glomerulosclerosis and renal fibrosis in rats with subtotal renal ablation. Eighty‐two female Wistar rats weighing 180–220 g were divided into two groups: 49 rats were subjected to 5/6 renal ablation and 33 to sham operation. Urinary albumin excretion, blood pressure and glomerular filtration rate (GFR) were evaluated after the surgical procedure. We also performed histology and immunohistochemistry and determined mRNA for TGF‐β1 in the kidneys of these rats 8, 15, 30 and 90 days after operation. The results showed progressively higher immunohistochemical TGF‐β1 staining in rats with subtotal renal ablation. Cortical renal content of TGF‐β1 mRNA was also higher in these animals and peaked at day 15.The existence of a temporal association between glomerulosclerosis, interstitial fibrosis and intense mononuclear cellular infiltration on the one hand and higher immunohistochemical TGF‐β1 staining in the renal cortex on the other show that this polypeptide may contribute to the development of renal fibrosis in this model.
Muscarinic modulation of endogenous noradrenaline release from adrenergic terminals in the guinea‐pig colon
Authors: Marino F. , Cosentino M. , De Ponti F. , Giaroni C. , Somaini L. , Bombelli R. , Ferrari M. , Aasen A.J. , Lecchini S. , Frigo G. 
Published: November 2003

1 The present study examined the role of muscarinic receptors in the modulation of noradrenaline (NA) release in the guinea‐pig isolated distal colon. The spontaneous endogenous NA overflow assayed by HPLC‐ED was taken as an index of NA release from enteric noradrenergic nerve terminals. 2 Physostigmine (10 μm) significantly enhanced spontaneous endogenous NA overflow. Hyoscine (muscarinic antagonist), (R)‐(‐)‐trihexyphenidyl and telenzepine (M1‐selective antagonists), and 11[[2‐[(diethylamino)methyl]‐1‐piperydil]acetyl]‐5,11‐dihydro‐6H‐pyrido[2,3‐b][1,4]benzodiazepine‐6‐one (AF‐DX 116, M2‐selective antagonist) inhibited NA overflow in a concentration dependent manner, with the following EC50 values: 131.74 (18.19–953.96), 101.62 (58.83–175.60), 150 (60–330), 30 (5–170) nm, respectively. 4‐diphenylacetoxy‐N‐methylpiperidine methiodide (4‐DAMP, M1‐ and M3‐ selective antagonist) had no significant effect up to 100 μm. 3 The muscarinic agonist oxotremorine inhibited NA overflow in a concentration dependent manner, with an EC50 value of 0.67 (0.30–1.51) μm. The response to oxotremorine was inhibited by muscarinic antagonists with the following order of potency: hyoscine = (R)‐(‐)‐trihexyphenidyl = telenzepine > 4‐DAMP >> AF‐DX 116. 4 In the presence of 3 μm tetrodotoxin (TTX), the effect of oxotremorine and 4‐DAMP was unchanged, while hyoscine, (R)‐(‐)‐trihexyphenidyl, telenzepine and AF‐DX 116, instead of inhibiting, significantly enhanced NA overflow. 5 The present results indicate that, in the guinea‐pig colon, endogenous acetylcholine sustains spontaneous NA release by activating muscarinic receptors possibly located on interneurones. In addition, inhibitory muscarinic receptors may exist on adrenergic terminals.
Adrenergic and nitrergic responses of the rat isolated anococcygeus muscle to a new toxin (makatoxin I) from the venom of the scorpion Buthus martensi Karsch
Authors: Gong J.P. , Gwee M.C.E. , Gopalakrishnakone P. , Manjunatha Kini R. , Chung M.C.M. 
Published: November 2003

1 Makatoxin I (MkTx I) is a new toxin purified from the venom of the scorpion Buthus martensi Karsch. Contractile (excitatory, adrenergic) and relaxant (inhibitory, nitrergic) responses of the rat isolated anococcygeus muscle (Acm) to MkTx I were investigated. 2 MkTx I (0.28 μm) produced a rapid and very marked rise in the tone of the Acm which then gradually waned to the control baseline. Phentolamine (5 μm), guanethidine (5 μm), tetrodotoxin (2 μm) and reserpine pretreatment in vivo (5 mg kg−1 s.c. at 24 h and 5 mg kg−1 i.p. at 3 h) completely blocked the contractile responses of the Acm to MkTx I. The responses to noradrenaline (NA) were blocked by phentolamine, but were potentiated by guanethidine. 3 MkTx I (0.28 μm) also marked and rapidly relaxed the tone of the carbachol (CCh; 3 μm), precontracted Acm. The addition of sodium nitroprusside (SNP; 1 μm) also produced a marked and rapid relaxation of the Acm. TTx (2 μm) or NG‐nitro‐L‐arginine methylester (L‐NAME, 50 μm) markedly inhibited the relaxant responses of the Acm to field stimulation (FS) as well as to MkTx I, but not the responses to SNP. 4 Therefore, the contractile responses of the rat anococcygeus muscle to MkTx I can be attributed to the release of transmitter NA acting on postjunctional α‐adrenoceptors, whereas the relaxant responses of the Acm to MkTx I involve the release of nitric oxide as the neurotransmitter which, presumably, results in the activation of the enzyme guanylate cyclase leading to relaxation of the muscle.
Age‐related changes in the reactivity of post‐synaptic adrenoceptors in the rat vas deferens: differences between the epididymal and prostatic portion
Authors: Markus R. P. , De Avellar M. C. W. 
Published: November 2003

1 Age‐related changes in the reactivity of postsynaptic α‐adrenoceptors of isolated portions (epididymal and prostatic) and in whole vas deferens have been studied using 4, 12 and 20 month‐old rats. 2 The pD2 values for adrenaline‐induced contractions were reduced in the epididymal portion and whole vas deferens of middle‐aged and old animals, but not in the prostatic portion. No age related change to phenylephrine or clonidine sensitivity was observed. 3 pA2 values of prazosin and yohimbine were not changed by aging in any preparation. Phentolamine pA2 values were reduced in the epididymal portion and in the whole vas deferens when adrenaline, but not when phenylephrine concentration–response curves were displaced by the antagonist. The mean pA2 value of yohimbine (6.78) indicates that this antagonist blocks α1‐adrenoceptors in the rat vas deferens. 4 The data presented here suggest that age‐related decreases in the sensitivity to adrenaline and phentolamine (when measured by displacing adrenaline concentration–effect curves) in the whole vas deferens are probably due to a variation in the proportion of α1‐adrenoceptor subtypes in the epididymal portion of the rat vas deferens.