bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of alternating and direct electrical current application on the odontoblastic layer in human teeth: an in vitro study
Authors: Alwas‐Danowska H. M. , Huysmans M.‐C. D. N. J. M. , Verdonschot E. H. 
Published: March 2003

Alwas‐Danowska HM, Huysmans M‐CDNJM, Verdonschot EH. Effects of alternating and direct electrical current application on the odontoblastic layer in human teeth: an in vitro study. International Endodontic Journal, 32, 459–463 1999.Aim The aim of this study was to investigate the influence of a low intensity alternating current on the odontoblasts and odontoblast layer and compare this with the effects of a direct current.Methodology Teeth extracted for orthodontic reasons were immersed in physiological saline stabilized with thymol crystals. Within 1h of extraction, an alternating or direct current was applied on the crown in the direction of the apex of the tooth for 120–360s. The current doses were 12, 30, 60, 600 1800, 3600, 7200, 24 000 and 144000 μC. The teeth were fixed in Bouin or Baker fluids, the pulps removed, dehydrated and immersed in paraffin, then sectioned, stained with haematoxylin and eosin, and studied under a light microscope.Results Neither direct nor alternating current, similar to that applied in electrical caries diagnosis caused histological changes in the odontoblasts.Conclusions There was no difference between direct and low intensity alternating current in the response of the odontoblast.
Reliability of radiographic observations recorded on a proforma measured using inter‐ and intra‐observer variation: a preliminary study
Authors: Saunders M. B. , Gulabivala K. , Holt R. , Kahan R. S. 
Published: March 2003

Aim  The aim of this preliminary study was to test the reliability of radiographic evaluation of features of endodontic interest using a newly devised data collection systemMethodology  Twelve endodontic MSc postgraduate students and one specialist endodontist examined sample radiographs derived from a random selection of 42 patients seen previously on an Endodontic New Patient Clinic (EDI). Each student examined a random selection of 8–9 roots on periapical radiographs of single‐ and multirooted teeth, with and without previous root canal therapy and 3–4 dental panoramic tomograms (DPTs). A total of 100 roots were examined. A proforma was used to record observations on 67 radiographic features using predefined criteria. Intra‐observer agreement was tested by asking the students to re‐examine the radiographs. The principle investigator and the specialist endodontist examined the same radiographs and devised a Gold Standard using the same criteria. This was compared with the student assessments to determine inter‐observer variation. The postgraduates then attended a revision session on the use of the form. Each student subsequently examined 8–9 different roots from the pool of radiographs. A further assessment of inter‐observer variation was made by comparing these observations with the Gold Standard.Results  Of the 67 radiographic features, only 25 had sufficient response to allow statistical analysis. Kappa values for intra‐ and inter‐observer variation were estimated. These varied depending on the particular radiographic feature being assessed. Fifteen out of 25 intra‐observer recordings showed ‘good’ or ‘very good’ Kappa agreement, but only three out of 25 inter‐observer observations achieved ‘good’ or ‘very good’ values. Inter‐observer variation was improved following the revision session with 16 out of 25 observations achieving ‘good’ or ‘very good’ Kappa agreement.Conclusions  Modification to the proforma, the criteria used, and training for radiographic assessment were considered necessary to improve the accuracy and reproducibility of the observations entered.
Evaluation of apical sealing of three endodontic sealers
Authors: De Almeida W. A. , Leonardo M. R. , Filho M. Tanomaru , Silva L. A. B. 
Published: March 2003

De Almeida WA, Leonardo MR, Tanomaru Filho M, Silva LAB. Evaluation of apical sealing of three endodontic sealers. International Endodontic Journal, 33, 25–27, 2000.Aim  The apical sealing ability of three different endodontic sealers was evaluated in extracted teeth using dye penetration.Methodology The root canals of 99 extracted human maxillary central incisors were prepared sequentially 2mm beyond the apical foramen with a size 55 Nitiflex file. The teeth were divided into three experimental groups and obturated by lateral condensation of cold gutta‐percha and one of the following sealers: group 1, zinc oxide and eugenol sealer (Fill Canal); group 2, glass ionomer sealer (Ketac‐Endo) and group 3, epoxy resin sealer (AH Plus). The teeth were covered with nail varnish to within 1mm of the apical foramen and immersed in 2% methylene blue in areduced pressure environment for 24h. After this period, the teeth were washed and cut longitudinally for apical leakage analysis. The values were obtained from the maximum depth of leakage as well as the average between the maximum and minimum values observed for each group.Results  Statistical evaluation of the results showed no significant difference in the leakage between Fill Canal and Ketac‐Endo (P >0.05). Leakage with AH Plus was significantly less (P <0.01) than with the other sealers.Conclusions  All three sealers allowed some leakage to occur. Leakage with AH Plus was significantly different than with Fill Canal or Ketac‐Endo.
Detection of a transitional ion concentration zone during electronic measurement of root canal length: a study in vitro
Authors: Tamarut T. , Kovačević M. , Uhač I. 
Published: March 2003

AbstractAimThe aim of this study was to examine the importance of a transitional ion concentration zone at the apical foramen during electronic root canal length measurement (ERCLM).MethodologyThe model comprised 21 extracted single‐rooted human teeth, divided into two experimental groups and one control group, each of seven teeth. The anatomical tooth length was determined from the site of reference on the tooth crown to the canal orifice and was measured using an endodontic file and a vernier caliper. Two aqueous solutions of various NaCl, KCl and CaCl2 concentrations were mixed with agar. The Na+, K+ and Ca++ concentrations corresponded to the average value of each group as determined by atomic spectrophotometry evaluation of the extirpated human pulps. The agar containing cations was injected into the root canals after their preparation to a foramen diameter of 0.70 mm. The control teeth were then completely immersed in agar having the same concentration of cations as the agar inside the canal. In the first experimental group (group 1), the teeth were immersed in agar so that the ion concentration was higher inside the canal; in the second experimental group (group 2), the concentrations were reversed. In all three groups, ERCLM was performed by an EED 11 – resistance type device. Length d1 was defined as the length of the root when measured to a value one degree less than the test value. Length d2 was defined as the length of the root inducted by the test value, which corresponded to the resistance of the periapical agar.ResultsIn group 1 the average d1 length was 0.44 ± 1.05 shorter than the anatomical foramen (AF), and in group 2, 1.11 ± 0.43 mm longer than AF. In the control group the d1 length was on average − 3.02 ± 3.72 mm from the AF. The d1 values of all groups were not statistically significantly different from the anatomical length (AL). In all three experimental groups the d2 length was statistically significantly different from the AL (P < 0.05, t‐test); group 1 d2 = AL + 6.32 ± 1.38 mm; group 2 d2 = AL + 6.27 ± 1.47; control group d2 = AL + 9.15 ± 1.00 mm.ConclusionsThe results of this study indicated that when the electroconductive medium in the canal had a different ion concentration than the periapex, and the canal orifice had a wide diameter (0.70 mm), the transitional concentration zone influenced the accuracy of measurement during ERCLM with a resistance type device. When ion concentrations inside and outside the canal were identical, in teeth with a wide foramen diameter (0.70 mm or more) the lack of a transitional ion concentration zone meant that the length of the root canal could not be determined by ERCLM.
Endodontic teaching in Philippine dental schools
Authors: Cruz E. V. , Jimena M. E. M. , Puzon E. G. , Iwaku M. 
Published: March 2003

AbstractAimThe aim of this study was to evaluate the pattern of undergraduate endodontic teaching in Philippine dental schools.MethodologyData were gathered by sending questionnaires to the deans of the 23 dental schools in the country to determine details of the teaching of root canal treatment in permanent teeth. The covering letter requested that endodontic staff complete the questionnaire.ResultsTwenty of 23 dental schools returned completed questionnaires. Similarities were observed in the timing of undergraduate endodontic teaching, working length determination, and root canal preparation technique. Irrigating fluids recommended included one or a combination of the following: sodium hypochlorite, hydrogen peroxide, distilled water and EDTA. The root canal medicaments popularly employed were CMCP and eugenol. Most schools used slow‐setting zinc oxide eugenol cement as sealer. Differences between schools were noted in the laboratory component of the course. The time allotted for the laboratory exercises, as well as the number of teeth used, differed greatly between each school. An inadequate tutor to student ratio was noted in the majority of schools. Teaching aids were limited and, in most instances, produced by faculty members. Most faculty members teaching endodontics had no specialist training.ConclusionThe results of this study have demonstrated that there is a need to review endodontic teaching in the majority of the Philippine dental schools to ensure that the course content and curriculum employed by all schools meet specified standards and that appropriate measures should be considered to enhance the learning experience of students.
An unusual case of furcation external resorption
Authors: Wood P. , Rees J. S. 
Published: March 2003

AbstractAimTo describe the presentation and management of an unusual external root resorption.SummaryAn unusual external inflammatory root resorption presented in the furcation of a mandibular first molar. Review of earlier radiographs suggested that the lesion was non‐progressive. Occlusal trauma associated with anterior open bite was the most likely aetiological factor. No active treatment was prescribed.Key learning points

External resorption may occur following loss of the external root surface.
Occlusal trauma may be a propagating stimulus for progressive resorption.
Lesions may sometimes be non‐progressive, and treatment may therefore be more damaging than observation.
The use of calcium sulphate in the surgical treatment of a ‘through and through’ periradicular lesion
Authors: Pecora G. , De Leonardis D. , Ibrahim N. , Bovi M. , Cornelini R. 
Published: March 2003

AbstractAim This randomized, controlled, clinical study was designed to evaluate the adjunctive effect of calcium sulphate grafts on the surgical treatment of through and through periradicular lesions.Methodology  Twenty patients each with one tooth showing evidence radiologically of a periradicular lesion wider than 10 mm, with lack of both buccal and lingual cortical bony plates and an indication for surgery were selected for the study. Ten teeth were treated with apicectomy, root‐end filling and grafting of the bone defect with calcium sulphate prior to suturing (test group). The other 10 teeth received the same surgical therapy but no grafting with calcium sulphate (control group). The outcome of the healing process was evaluated at 6 and 12 months radiographically following the criteria reported by Rud and Andreasen.Results At the six‐ and 12‐month evaluation the test group had seven teeth with complete healing and two with incomplete healing, whilst the control group showed three teeth with complete healing, five with incomplete healing and one with unsatisfactory healing. One tooth in each group had to be extracted because of a vertical fracture that occurred during the follow‐up period.Conclusions  The results of the study demonstrate that the addition of calcium sulphate as a bone graft during the conventional surgical treatment of through and through lesions improves the clinical outcome. Histological analysis is desirable to investigate the quality of tissues formed using the two surgical procedures.
Frequency and distribution of endodontically treated teeth and apical periodontitis in an urban Danish population
Authors: Kirkevang L‐L. , Hörsted‐Bindslev P. , Ørstavik D. , Wenzel A. 
Published: March 2003

AbstractAim The aim of this study was to investigate the prevalence of endodontically treated teeth and apical periodontitis (AP) in a Danish population.Methodology From Aarhus County 614 individuals were radiographically examined, and the frequency of endodontic treatment and periapical status of all teeth were assessed. The year of birth of the subjects ranged from 1935 to 1975. The chi‐squared test was used to determine the significance of differences between males and females and amongst age and tooth groups for the following parameters: AP, the number of endodontically treated teeth, and the number of endodontically treated teeth with AP.Results A total of 15 984 teeth were examined; of these 538 (3.4%) had AP and 773 (4.8%) had been endodontically treated. Of the endodontically treated teeth, 404 (52.2%) had AP. Females had more endodontically treated teeth than males; otherwise, no effect of gender was observed. Significantly more molars (P < 0.01) had been endodontically treated (8.1%) compared to premolars (5.4%) and anterior teeth (2.5%). The prevalence of AP in connection with molars was significantly (P < 0.01) higher (7.0%) than premolars (2.8%) and anterior teeth (1.5%). The prevalence of endodontically treated teeth and of teeth with AP gradually increased with age.Conclusions  The average number of teeth, the number of teeth with AP and the number of teeth with endodontic treatment in Danish adults were comparable to findings in other European countries. The frequency of endodontically treated teeth with AP was found to be high compared to that demonstrated in other epidemiological studies.
Aetiology of root canal treatment failure: why well‐treated teeth can fail
Authors: Siqueira J. F. 
Published: March 2003

AbstractLiterature reviewRoot canal treatment usually fails when the treatment is carried out inadequately. However, there are some cases in which the treatment has followed the highest standards yet still results in failure. In most of the cases, the endodontic failure results from persistent or secondary intraradicular infection. Extraradicular infections may also be implicated in the failure of some cases. In addition, it has been claimed that a few cases can fail because of intrinsic or extrinsic nonmicrobial factors. The purpose of this paper is to discuss the aetiology of the failure of root canal treatment, particularly in cases of well‐treated root canals. Indications for the treatment of endodontic failures are also discussed.
Root and canal morphology of Burmese mandibular molars
Authors: Gulabivala K. , Aung T. H. , Alavi A. , Ng Y‐L. 
Published: March 2003

AbstractAimTo study the root canal morphology of Burmese mandibular molars using a canal staining and tooth clearing technique.MethodologyMandibular molars (331) were collected from indigenous Burmese patients and designated; first (139), second (134), third (58) molars. Following pulp tissue removal and staining of the canal systems with Indian ink, the teeth were decalcified and rendered clear with methyl salicylate. Under magnification (×3), the following features were evaluated: (i) root number and morphology, (ii) number of canals per root, (iii) root canal configuration (Vertucci’s classification), (iv) number of apical foramina per root, (v) number and location of lateral canals and (vi) the presence of intercanal communications.ResultsMost of the mandibular molars had two separate roots (90% in first molars, 58% in second molars, 53% in third molars) and three‐rooted teeth were (10%) confined to first molars. C‐shaped roots occurred in 22.4% of mandibular second molars and a further 14.9% had two fused roots. The majority (81–100%) of conical distal roots possessed a simple type I (single canal) configuration. Whilst the canal system of mesial roots was more complex; 52–85% contained two canals, of which type II (two orifices, one foramen) and type IV (two separate canals) were the most prevalent. A broad range of 6.5–70% had intercanal communications. Fused/single‐rooted molars had a wide variety of canal system types but intercanal communications were rare except in C‐shaped roots (33%) of second molars. The majority of roots of all molars contained one or two apical foramina (91–96%) and the apical third had the highest prevalence of lateral canals.ConclusionsThere was a high prevalence of three‐rooted mandibular first molars and C‐shaped roots/canals in mandibular second molars from a Burmese population. Conical roots tend to have simple canal systems, whilst flatter/broader roots have more complex canal systems.
Enterococcus faecalis– a mechanism for its role in endodontic failure
Authors: Love R. M. 
Published: March 2003

AbstractAimThe aim of this study was to identify a possible mechanism that would explain how E. faecalis could survive and grow within dentinal tubules and reinfect an obturated root canal.MethodologyCells of Streptococcus gordonii DL1, Streptococcus mutans NG8, or E. faecalis JH2–2 were grown in brain heart infusion broth containing various amounts of human serum for 56 days. The ability of the three species to invade dentine and bind to immobilized type 1 collagen in the presence of human serum was assessed by dentine invasion and microtitre well experiments.ResultsAll three species remained viable over the period of the experiment when grown in human serum. Cells of all three bacteria were able to invade dentine and bind to immobilized collagen. Both of these properties were inhibited by the presence of collagen in the cell solution. Human serum inhibited dentine invasion and collagen adhesion by S. gordonii DL1 and S. mutans NG8, whilst dentine invasion by E. faecalis JH2–2 was reduced in the presence of serum, but not inhibited, and binding to collagen was enhanced.ConclusionsIt is postulated that a virulence factor of E. faecalis in failed endodontically treated teeth may be related to the ability of E. faecalis cells to maintain the capability to invade dentinal tubules and adhere to collagen in the presence of human serum.
A new technique for the study of periapical bone lesions: ultrasound real time imaging
Authors: Cotti E. , Campisi G. , Garau V. , Puddu G. 
Published: March 2003

AbstractAim This study describes the use of a real time‐ultrasound imaging technique (echography) for the study of periradicular lesions.Methodology Twelve patients with periapical lesions of endodontic origin, diagnosed with conventional clinical and radiographic examination, were examined further using echography at the site of the diagnosed lesions. Each lesion was echographically characterized and described by an expert echographist together with an endodontist. Once the major echographic features were identified, information on the size of the lesion, its content, and its vascular supply was obtained and recorded. A tentative differential diagnosis between a cyst and a granuloma was made based on the data.Results In all cases it was possible to obtain an echographic image. It was also possible to measure the lesions, to evaluate their content and to view their vascularization in different regions of the mouth.Conclusions Ultrasound real time imaging is a promising diagnostic technique in endodontology, but further work is required to refine the process.
The ferrule effect: a literature review
Authors: Stankiewicz N. R. , Wilson P. R. 
Published: March 2003

Abstract Literature review A ferrule is a metal ring or cap used to strengthen the end of a stick or tube. It has been proposed that the use of a ferrule as part of the core or artificial crown may be of benefit in reinforcing root‐filled teeth. A review of the literature investigating this effect is presented. The literature demonstrates that a ferrule effect occurs owing to the artificial crown bracing against the dentine extending coronal to the crown margin. Overall, it can be concluded that a ferrule is desirable, but should not be provided at the expense of the remaining tooth/root structure.
Phytochemicals and the breakthrough of traditional herbs in the management of sexual dysfunctions
Authors: Adimoelja Arif 
Published: March 2003

Traditional herbs have been a revolutionary breakthrough in the management of erectile dysfunction and have become known world‐wide as an ‘instant’ treatment. The modern view of the management of erectile dysfunction subscribes to a single etiology, i.e. the mechanism of erection. A large number of pharmacological agents are orally consumed and vasoactive agents inserted intraurethrally or injected intrapenially to regain good erection.Modern phytochemicals have developed from traditional herbs. Phytochemicals focus their mechanism of healing action to the root cause, i.e. the inability to control the proper function of the whole body system. Hence phytochemicals manage erectile dysfunction in the frame of sexual dysfunction as a whole entity.Protodioscin is a phytochemical agent derived from Tribulus terrestris L plant, which has been clinically proven to improve sexual desire and enhance erection via the conversion of protodioscine to DHEA (De‐Hydro‐Epi‐Androsterone).Preliminary observations suggest that Tribulus terrestris L grown on different soils does not consistently produce the active component Protodioscin.Further photochemical studies of many other herbal plants are needed to explain the inconsistent results found with other herbal plants, such as in diversities of Ginseng, Eurycoma longifolia, Pimpinella pruacen, Muara puama, Ginkgo biloba, Yohimbe etc.
How work‐place conditions, environmental toxicants and lifestyle affect male reproductive function1
Authors: Bonde Jens Peter , Storgaard Lone 
Published: March 2003

SummaryMajor temporal and geographical shifts in male reproductive function is presently an issue worldwide. The hormonal disruption hypothesis has achieved considerable attention but epidemiological evidence in support of the theory is lacking. Several occupational hazards to male reproductive function are known but exposure prevalences are hardly sufficient to play a role for reduced sperm count in the general male population. Sedentary work may be an exception. Perhaps prolonged time in the sedentary position exhausts the testicular heat regulation. But so far studies addressing implications of the heat hypothesis in the general population are few. Neither change of sexual behaviour nor reduced period of sexual continence seems to be a likely explanation. Tobacco smoking and consumption of caffeine and alcoholic beverages in adulthood have a rather marginal impact on spermatogenesis and can hardly explain major shifts or regional differences in male reproductive health. However, prenatal effects following smoking during pregnancy might play a role because we have witnessed a smoking epidemic among fertile women in some countries during the second half of the twentieth century. Moreover, if genetic factors play more than a marginal role for testicular function and sperm count, pregnancy planning resulting in reduced family size during the past 100 years could possibly explain a decline in semen quality because the most fertile part of the population reproduce less while the subfertile probably continue to get a limited number of children.