bluuebunny/crossref_metadata_2025_split huggingface dataset:
Marginal leakage of Gallium Alloy root‐end fillings: an in‐vitro assessment
Authors: WHITWORTH J. M. , KHAN A. Q. 
Published: September 2007

SummaryThe sealing ability of amalgam and Gallium Alloy Gallium Filling (GF) root‐end fillings was evaluated in vitro using a highly uniform collection of sheep incisor roots. Following ultrasonic canal debridement and orthograde obturation with gutta‐percha and sealer, root‐end cavities were prepared in 100 roots and filled with amalgam (50 teeth) or Gallium Alloy GF (50 teeth). Twenty‐five teeth from each group were subjected to immediate dye leakage assessment under vacuum conditions with methylene blue dye (2%), pH 7. Linear dye penetration was measured following longitudinal splitting. The other 25 teeth from each group were incubated in Ringer's solution for 12 weeks before leakage assessment by the same method. Control teeth were included in each component of the study.Mean linear dye penetration was: amalgam—5.17mm at baseline, 2.33mm after 12 week's incubation; Gallium Alloy GF—2.21mm at baseline, 1.41mm after 12 week's incubation. The apical marginal seal of both materials improved significantly following storage in Ringer's solution (P < 0.001). Gallium Alloy GF provided a better apical seal than amalgam, both at baseline and following storage (P < 0.001). Subjective evaluation of the general handling characteristics of Gallium Alloy GF revealed that it was a more difficult material to manipulate than amalgam, largely because of its wetting ability and consequent adhesion to dental instruments.
Endodontically treated teeth and periapical findings in the elderly
Authors: SOIKKONEN K. T. 
Published: September 2007

SummaryThe radiographic quality of root‐canal fillings, the prevalence of periapical findings and their associations with gender and age and were investigated in 133 dentate old people living at home (45 males and 88 females, aged 76, 81, and 86 years and who had endodontically treated teeth or periapical lesions.Sixteen per cent of the endodontically treated teeth (n= 507) exhibited periapical lesions, compared with 4% for the teeth not endodontically treated (P < 0.0001) (χ2 test). Lesions were least prevalent in association with radiographically adequate root canal fillings (10%), and most prevalent in teeth with root canal post perforation (100%). Overfilled root canals and multi‐rooted teeth with one or more unfilled roots also showed a high percentage of lesions (19% and 22%, respectively). Men had more periapical lesions than women in endodontically treated teeth (P < 0.0001, Mann‐Whitney U‐test), a finding contrary to previous studies in younger subjects. There were no other statistically significant differences between the sexes or age groups, although the percentage of root‐filled teeth increased with age.
The effect of retrograde cavity design on microleakage of amalgam fillings
Authors: GULABIVALA K. , SAYED A. A. , WILSON M. 
Published: September 2007

SummaryA phantom head model was modified to simulate as closely as possible the limited access encountered during periapical surgery on maxillary anterior teeth. Extracted human maxillary anterior and mandibular canine teeth were placed in this model in a standardized position for root resection, retrograde cavity preparation and filling with amalgam. Three different designs of retrograde cavities were evaluated: the conventional class 1 cavity, the slot cavity and a previously unreported approach, the funnel cavity.Upon completion of the retrograde filling, the teeth were removed from the model and subjected to microleakage tests by placing radiolabelled lipopolysaccharide in a reservoir created coronal to the retrograde fillings. Leakage was quantified by measurement of radioactivity in scintillation counter.It was found that the retrograde fillings in the funnel cavity leaked significantly less than those in the other two cavity designs. There was no statistically significant difference in leakage between the conventional class 1 and the slot cavities up to the thirtieth day 30.
In‐vitro measurement of apieally extruded irrigant in primary molars
Authors: WILLIAMS C. E. C. S. , REID J. S. , SHARKEY S. W. , SAUNDERS W. P. 
Published: September 2007

SummaryThis study investigated the weights of irrigant extruded apically through extracted primary molar teeth. The aim was to compare the weight of canal irrigant (isotonic sodium chloride solution) extruded through the root canal using either a syringe fitted with a 27‐gauge needle or an endosonic unit. Root canals were divided randomly into five groups of 15 discrete canals. The area of each apical foramen was recorded prior to the use of the irrigant. For each irrigation technique the maximum depth of penetration of the needle tip/file was either 2–3 mm or 6–7 mm from the apical foramen. In four groups the crowns of the teeth were in a mandibular position, in the fifth group the teeth were inverted to simulate maxillary teeth. The results showed that irrigant was extruded using both methods. There was significantly less extrusion of irrigant when the endosonic unit was used (P < 0.01). There was no statistically significant relationship between foramen area and amount of extruded irrigant (P > 0.05). There was no significant extrusion of irrigant in teeth with closed apices when either of the two methods was used (P>0.05).
Long‐term evaluation of endodontic and periodontal treatment
Authors: JAOUI L. , MACHTOU P. , OUHAYOUN J.P. 
Published: September 2007

SummaryOne hundred and ninety‐five teeth in 35 patients with periodontitis who had received both endodontic and periodontal treatment were evaluated 9 years after endodontic treatment and 8 years after periodntal treatment. Some 91.4% of cases were well maintained and 8.6% showed a deterioration in their periodontal condition. Twelve of the 195 teeth with endodontic treatment were lost, eight for periodontal codition. Twelve of the 195 teeth with endodontic treatment were lost, eight for periodontal reasons, three as a result of fracture and one because of caries, and the periodontal condition of 10 teeth had worsened. An apical lesion formed on one tooth. The results indicate that the risk of endodontic failure in this group of 195 teeth is very low, and that there is little risk of tooth loss for periodontal reasons, provided that the patients receive suppportive periodontal treatment.
Clinical diagnosis of internal resorption: an exception to the rule
Authors: GULABIVALA K. , SEARSON L. J. 
Published: September 2007

SummaryThis paper describes a case in which the radiographic appearance of a resorptive lesion in a mandibular incisor tooth posed difficulty in the diagnosis of its origin. The lesion did not conform to the normally accepted criteria for diagnosis of internal resorption. Clinical examination did not support the diagnosis of external cervical resorption. Serial histological section of the extracted tooth subsequently confirmed the diagnosis of internal resorption. The criteria for differential diagnosis of resorptive lesions with smooth outlines in the cervical regions of teeth are discussed together with the rationale for their management.
Factors associated with endodontic flare‐ups: a prospective study
Authors: IMURA N. , ZUOLO M.L. 
Published: September 2007

SummaryThe purpose of this prospective study was to assess the incidence of flare‐ups (a severe problem requiring an unscheduled visit and treatment) among patients who received endodontic treatment by the two authors in their respective practices during a period of one year, and also to examine the correlation with pre‐operative and operative variables. The results showed an incidence of 1.58% for flare‐ups from 1012 endodontically treated teeth. Statistical analysis using the chisquare test (P<0.05) indicated that flare‐ups were found to be positively correlated with multiple appointments, retreatment cases, periradicular pain prior to treatment, presence of radiolucent lesions, and patients taking analgesic or anti‐inflammatory drugs. In contrast, there was no correlation between flare‐up, and age, sex, different arch/tooth groups and the status of the pulp.
The adaptation of mechanically softened gutta‐percha to the canal walls in the presence or absence of smear layer: a scanning electron microscopic study
Authors: PALLARÉS A. , FAUS V. , GLICKMAN G. N. 
Published: September 2007

SummaryThe objective of this study was to compare the adaptation of mechanically softened gutta‐percha to the root canal wall in the presence and absence of smear layer. The root canals of 20 freshly extracted human maxillary incisors were cleaned and shaped. Prior to obturation, 10 root canals were irrigated with 20 ml of 50% citric acid followed by 20 ml of 5.25% sodium hypochlorite. All canals were obturated with mechanical compaction of gutta‐percha and AH‐26 sealer. After 72h, each tooth was fractured in half. Scanning electron microscopy demonstrated that the sealer had formed a continuous layer in contact with the canal walls, becoming progressively thinner towards the apex. The sealer pentrated into the dentinal tubules along with projections of gutta‐percha only in those teeth without smear layer.
A computerized method for the evaluation of root canal morphology
Authors: BLAŠKOVIĆ‐ŠUBAT V. , SMOJVER I. , MARIČIĆ B. , ŠUTALO J. 
Published: September 2007

SummaryThe objective of this research was to develop a technique that would allow three‐dimensional imaging of root canals utilizing computer image processing. Ten single‐rooted permanent human teeth with mature apices were analysed. The teeth were decoronated and fixed on boards with the long axis of the root perpendicular to the board. The cross‐sectioning started at the root apex and continued in the coronal direction, roughly perpendicular to the long axis of the root. The samples were divided into two groups. The first five samples were sectioned 15 times, each section being 0.5‐mm thick, in order to obtain the three‐dimensional reconstruction of the root and the root canal. The second group of five samples served for the graphical reconstruction of the apical portion of the root canal. The root apex of each sample was cross‐sectioned 19 times and each section was 0.2‐mm thick. After each section, the root canal contour was defined utilizing the calibrated net with coordinate system in the ocular of the stereo‐microscope. The coordinates of the root canal cross‐section contour thus determined, together with the value of the thickness of each cut, were relevant input data for the reconstruction of the root canal cross‐sections, longitudinal sections and for the final three‐dimensional rebuild of the root and the root canal model. This technique appears to be highly accurate in determining the anatomy of the root canal system and may also be applied in other fields of dental research.
Apical and coronal seal of roots obturated with a dentine bonding agent and resin
Authors: LEONARD J. E. , GUTMANN J. L. , GUO I. Y. 
Published: September 2007

SummaryThe efficacy of sealing root canal systems with a dentine bonding agent and resin cement was compared with that of a glass ionomer sealer. Scanning electron microscopic examination of the bonding agent‐dentine interface was also performed. The root canals of 50 single rooted teeth with mature apices were prepared chemo‐mechanically and the smear layer removed with 17% REDTA and 5.25% NaOCl. Specimens were divided into two groups of 24 teeth each. One group had the dentine conditioned with a 10:3 citric acid‐ferric chloride solution and obturated with the dentine bonding agent and resin, radiopaque C & B Metabond. The other group was obturated with the glass ionomer sealer, Ketac‐Endo and a single cone of gutta‐percha. After immersion in Indian ink for 90 h, the teeth were cleared and the quality of the apical and coronal seal was assessed using India ink dye penetration. There was a significantly better seal in both the apical and coronal directions when using the dentine bonding agent and resin obturation material. Scanning electron microscopic examination of the demineralized dentine and the C & B Metabond interface revealed the presence of the characteristic hybrid layer along with microtags of resin penetrating deep into the dentine tubules.
An in‐vitro study of smear layer removal and microbial leakage along root‐canal fillings
Authors: BEHREND G. D. , CUTLER C. W. , GUTMANN J. L. 
Published: September 2007

SummaryThe objective of this study was to determine the effect of removal of the smear layer on canal obturation as measured by penetration of bacteria from a coronal direction. Fifty‐four extracted human teeth were decoronated and instrumented in a uniform manner. Following instrumentation the root canals of 20 teeth were rinsed with 17% EDTA and 5.25% NaOCl to remove the smear layer before obturation. A second group of 20 teeth were flushed with NaOCl alone. The teeth of both groups were obturated with ThermafilTM plastic carriers and Roth's sealer. The root canals of another 10 teeth, five rinsed with EDTA and five without, were obturated with ThermafilTM without sealer. Two teeth serving as positive controls were instrumented but not obturated, while another set of two were sealed coronally and apically to serve as negative controls. The root surface of each tooth was sealed with nail varnish. A small chamber was thoroughly sealed around the coronal aspect of each tooth so that bacteria placed therein could move only through the obturated canal space. Each tooth was placed in a test tube containing sterile trypticase soy broth (TSB). An inoculum of Proteus vulgaris in TSB was placed in each coronal chamber at five day intervals and daily observations were made for bacterial growth in the apical reservoir for 21 days. Both positive control teeth showed bacterial penetration after 24 h. Neither of the two negative control teeth demonstrated penetration for the duration of the study. The frequency of bacterial penetration through teeth obturated with intact smear layer (70%) was significantly greater than that of teeth from which the smear layer had been removed (30%) P< 0.05. All but one tooth obturated without sealer exhibited bacterial penetration, irrespective of the presence or absence of smear layer. Removal of the smear layer enhanced sealability as evidenced by increased resistance to bacterial penetration.
In‐vitro antibacterial susceptibility of bacteria taken from infected root dentine to a mixture of ciprofloxacin, metronidazole and minocycline
Authors: HOSHINO E. , KURIHARA‐ANDO N. , SATO I. , UEMATSU H. , SATO M. , KOTA K. , IWAKU M. 
Published: September 2007

SummaryThe aim of this study was to clarify the antibacterial effect of a mixture of ciprofloxacin, metronidazole and minocycline, with and without the addition of rifampicin, on bacteria taken from infected dentine of root canal walls. The efficacy was also determined against bacteria of carious dentine and infected pulps which may the precursory bacteria of infected root dentine. This efficacy was estimated in vitro by measuring bacterial recovery on BHI‐blood agar Plates in the presence or absence of the drug combination. Bacteria ranging in number from 102 to 106 occurred in samples of infected root dentine (27 cases). However, none was recovered from the samples in the presence of the drug combination at concentrations of 25 μg ml‐1 each. The respective drug alone (10, 25, 50 and 75 μg ml‐1) substantially decreased the bacterial recovery, but could not kill all the bacteria. Bacteria taken from carious dentine (25 cases) and infected pulps (12 cases) were also sensitive to the drug combination. These results may indicate that the bactericidal efficacy of the drug combination is sufficiently potent to eradicate bacteria from the infected dentine of root canals.
Haemostasis in periradicular surgery
Authors: WITHERSPOON D. E. , GUTMANN J. L. 
Published: September 2007

SummaryThe successful performance of endodontic surgical procedures is predicated on many factors. However, the ability of achieve sustained tissue haemostasis in the surgical site is crucial to the performance of these procedures. This achievement improves vision in the surgical site, minimizes surgical time, enhances the surgical procedures (root‐end resection, preparation and filling), and reduces surgical blood loss, postsurgical haemorrhage and postsurgical swelling. A multitude of materials have used in dentistry and medicine to achieve both generalized and localized haemostasis, many without full assessment of their biological implications. The purpose of this paper is to provide a thorough and critical review of these materials from the perspective of surgical endodontics, highlighting their development, application and potential role in achieving proper haemostasis.
Variation in the microleakage produced by four different techniques in root fillings in a simulated root canal model
Authors: PATHOMVANICH S. , EDMUNDS D. H. 
Published: September 2007

SummaryAn in‐vitro investigation was performed to assess the extent of apical microleakage in simulated canals in clear resin blocks. Four different methods of producing dye penetration were employed: passive dye penetration alone, centrifugation alone, vacuum plus passive dye penetration, and increased pressure plus passive dye penetration. Forty simulated root canals were prepared and obturated. The specimens were randomly allocated into four groups and each group was subjected to a different leakage technique using methylene blue dye as the detector. The maximum apical dye penetration observed through each of the four faces of the blocks was recorded. There were large variations in the leakage recorded in each individual specimen and between the specimens within each group. There were statistically significant differences between passive dye penetration and each of the other three techniques. There was no significant difference between the centrifugation, vacuum and pressure techniques.
Microbiological root canal sampling: diffusion of a technology
Authors: MOLANDER A. , REIT C. , DAHLÉN G. 
Published: September 2007

SummaryDiffusion is the process whereby a technology enters and becomes part of the health‐care system. In the present study, diffusion of microbiological root canal sampling (MRS) among general dental practitioners within the city of Gothenburg was observed for 25 years, from the establishment of the Laboratory of Oral Microbiology in 1966. Laboratory records at 5‐year intervals were analysed and adopters were categorized as‘occasional’(1‐2 samples/year), 'selective’(3‐10) or‘regular’(>10) samplers. The diagnostic accuracy was assessed by analysing the results of culturing 5 74 samples referred in 1986. The acceptance rate varied between 2.9 and 5.1%, except in 1986 when 10.1% of the practitioners in the area referred root‐canal samples. While a minority of the adopters used MRS as a standard procedure, the strategy appeared to be directed towards selection of special cases. The results of culturing revealed a predominance of facultatives. Although evidence of contamination was found, the practitioners frequently appeared to produce valid microbiological samples.
Reasons for dentists’ acceptance or rejection of microbiological root canal sampling
Authors: MOLANDER A. , REIT C. , DAHLEN G. 
Published: September 2007

SummaryMicrobiological root canal sampling (MRS) has been found to be used by only a few Swedish general dentists. The present study addresses the reasons for their acceptance or rejection of the technology. A questionnaire was mailed to 240 general dentists practising within the city of Goteborg. The questionnaire concerned certain practice characteristics and attitudes to MRS. The data showed that MRS is mainly performed by dentists working with adult patients in private practice. The technology is rarely used routinely, but is applied in selected cases. The main reason for non‐adoption seems to be a perceived lack of relative advantage over conventional treatment strategies. Furthermore, opinions regarding the complexity and observability of the technology appear to influence acceptance significantly.
Factors affecting the cutting ability of sonic files
Authors: LUMLEY P. J. , HARRINGTON E. , ASPINWALL E. , BLUNT L. , WALMSLEY A. D. , MARQUIS P. M. 
Published: September 2007

SummaryThe aim of this study was to investigate the cutting ability of sonic files. A model system was developed and the following variables evaluated: file type, Heliosonic or Shaper; file length, 21 or 29 mm; power, air inlet ring opening of half or fully open; stroke length, 2 or 4 mm; stroke rate, one or two cycles per second; and load 50 or 100 g. A 26 full‐factorial analysis with two replications into the effect of the above variables on the cutting ability of the MM1500 sonic instrument was performed. A new size 25 file was used for each cut, together with water irrigation, and the substrate used was 1‐mm thick sections of bovine bone. The differences between the variables were significant (ANOVA, P< 0.001). However, examination of the F‐values showed that the most significant variable to affect cutting was load, followed by power, file type, stroke length and stroke rate, with the least significant variable being file length. The most significant interaction was between rate and length of stroke. An increase in stroke rate from one to two cycles per second at a stroke length of 2 mm produced an increase in cutting for both the Heliosonic and Shaper files. However, at the longer stroke length of 4 mm, the same increase in rate resulted in a decrease in cutting for the Shaper files. Therefore, it is suggested that operators should press the file against the canal wall and move it slowly to maximize cutting.
Detection of epidermal growth factor receptor in inflammatory periapical lesions
Authors: LIN L. M. , WANG S.‐L. , WU‐WANG C. , CHANG K.‐M. , LEUNG C. 
Published: September 2007

SummaryEpithelial cell proliferation is often observed in periapical lesions of endodontic origin. The mechanisms which stimulate the epithelial cell rests of Malassez to proliferate are not understood fully. Fifteen inflammatory periapical lesions (10 granulomas and five cysts) obtained from periapical surgery and six additional periapical lesions (four granulomas and two cysts) collected from extracted teeth were examined using immunohistochemical staining and 125I‐EGF (epidermal growth factor) binding assay to detect the presence of epidermal growth factor receptor. The results indicated that the periapical lesions without epithelial cell proliferation had a weak immunoperoxidase staining or low specific binding of i25I‐EGF. In contrast, the periapical lesions with epithelial cell proliferation and cyst formation exhibited a strong immunoperoxidase staining in the epithelial cells or high specific binding of 125I‐EGF.
Phantom tooth pain: a diagnosis of exclusion
Authors: BATTRUM D. E. , GUTMANN J. L. 
Published: September 2007

SummaryThis case report addresses the difficult diagnosis of phantom tooth pain (PTP). This is a syndrome of persistent pain in the teeth and oral structures following pulp extirpation, extraction, or rarely, an inferior alveolar nerve block. The incidence of this often misdiagnosed condition is estimated to be 3% of the population undergoing pulp extirpation, and is similar to phantom limb pain. The diagnosis of PTP is discussed here as a diagnosis of exclusion, after numerous interventions. Various treatment modalities are outlined and the use of non‐traditional pharmacological approaches for pain reduction are discussed.