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Single-rooted Teeth (single-rooted + tooth)
Selected AbstractsA survey of interfacial forces used during filing of root canalsDENTAL TRAUMATOLOGY, Issue 3 2000J. D. Regan Abstract , The pattern of dentine removal during endodontic instrumentation is influenced by many factors including the interfacial forces applied by the operator. The aim of this study was to investigate the influence of operators and different sizes and types of instruments on the magnitude of these interfacial forces. Single-rooted teeth were mounted on a cantilevered aluminium beam to which two pairs of single element strain gauges were joined in a half-bridge configuration and mounted at right angles to each other. The strain gauges were connected to an analogue-to-digital converter fitted in a micro-computer via conditioning amplifiers. This enabled strains to be recorded over a period of time. Twenty operators instrumented root canals using a series of hand instruments for 1 min each. The mean interfacial forces used by operators demonstrated a wide variation ranging from 9.06 g to 149.42 g (range of forces from 0,331 g) but there was a consistency in the relative magnitude for each operator. The 20 operators could be divided into 13 groups which were significantly different (,=0.05) from each other. There were significant differences (,=0.05) between the forces used for each of the K-Flex files (15, 25, 35, 45, and 70), the force increasing with the file size. There was also a significant difference (,=0.05) in the forces used between the Flexofile (#25) and the #25 K-Flex and Hedström files. However, there was no significant difference between the K-Flex and Hedström files. [source] Quality of root canal fillings performed by undergraduate dental students on single-rooted teeth,EUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 2 2006C. D. Lynch Introduction:, Root canal therapy is an accepted and successful form of tooth conservation. Educational guidelines require dental schools to ensure that their graduates are competent on graduation at performing root canal therapy. The aim of this investigation was to assess the technical quality of root canal fillings placed by undergraduate students in single-rooted teeth. Materials and methods:, A total of 100 radiographs of root canal fillings placed by undergraduate students in single-rooted teeth were examined under even illumination in a darkened room using ×2 magnification. These were graded as ,adequate', where the root canal filling was within 2 mm of the radiographic apex, ,under-filled', where the root canal filling was >2 mm from the radiographic apex, and ,over-filled', where the root canal filling was extruded beyond the radiographic apex. The presence of voids, fractured instruments, and root perforations were also noted. Results:, All teeth were obturated with gutta-percha and sealer (Roth Cement), using a cold lateral condensation technique. Of 100 teeth, 10% (n = 10) had voids. Of the remainder, 70% (n = 63) were judged to be ,acceptable', 21% (n = 19) were ,under-filled', and 9% (n = 8) were ,over-filled'. There was no evidence of fractured instruments or root perforations in any root filling examined. Conclusions:, The quality of root canal fillings placed in single-rooted teeth by undergraduate dental students at the University Dental School and Hospital, Cork was acceptable (63% of root fillings placed in single rooted teeth were graded as ,adequate'). The probable reasons for this are multi-factorial, but may be linked to the amount of pre-clinical and clinical teaching in endodontics at the University Dental School and Hospital, Cork. It should be remembered that factors other than radiographic quality/evidence must be considered when determining the outcome of root canal therapy. [source] Ex vivo evaluation of the accuracy and coefficient of repeatability of three electronic apex locators using a simple mounting model: a preliminary reportINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2010F. L. C. D'Assunção D'Assunção FLC, Albuquerque DS, Salazar-Silva JR, Dos Santos VC, Sousa JCN.Ex vivo evaluation of the accuracy and coefficient of repeatability of three electronic apex locators using a simple mounting model: a preliminary report. International Endodontic Journal, 43, 269,274, 2010. Abstract Aim, To compare ex vivo the accuracy and coefficient of repeatability of three electronic apex locators in locating the apical constriction. Methodology, Thirty-one single-rooted teeth were used. The teeth were sectioned at the cement,-enamel junction. A mounting model was used for the measurement of electronic length (EL). The Root ZX-II, the Mini Apex Locator and the Novapex were used for electronic measurements. Each electronic measurement was obtained and repeated. After the last measurement, the file was cemented in place, and the apical 4 mm of each root canal was exposed. The distance from the tip of the file to the apical constriction was determined by three investigators and compared with the corresponding ELs. Results, The coefficient of repeatability of all devices was acceptable: Root ZX-II, 0.04 mm; Mini Apex Locator, 0.10 mm; and Novapex, 0.08 mm. There was little variation in inter-examiner agreement; the ,C (Lin) correlation coefficient was 0.83 for examiners 1 and 2, 0.88 for examiners 1 and 3 and 0.99 for examiners 2 and 3. Using the Root ZX-II, 13 of 31 electronic measurements were located at the apical constriction (42%). Otherwise, the tip of the file was not located at the apical constriction in any of the electronic measurements with the other two devices. The Wilcoxon signed rank test did not reveal any statistical difference between the Root ZX-II measurements and the actual length (P = 0.628), but there was a statistical difference between the Mini Apex Locator and Novapex measurements and the actual length position (P < 0.05). Conclusions, The devices tested in this study had a high coefficient of repeatability. The Root ZX-II was accurate, but the Mini Apex Locator and Novapex were not accurate in locating the apical constriction. [source] Ex vivo microscopic assessment of factors affecting the quality of apical seal created by root-end fillingsINTERNATIONAL ENDODONTIC JOURNAL, Issue 8 2007S. I. Tobón-Arroyave Abstract Aim, (i) To evaluate the incidence of microcracks around root-end preparations completed with ultrasonic tips and their relationship with the root filling technique and thickness of surrounding dentine. (ii) To investigate the effect of rapid exposure to a water-soluble dye of Intermediate Restorative Material (IRM), Super Ethoxybenzoic Acid (sEBA) and Mineral Trioxide Aggregate (MTA), on the marginal adaptation and microleakage of root-end fillings. (iii) To describe the microstructure of the surface of root-end filling materials. Methodology, Ninety-two single-rooted teeth were divided into two groups (n = 46) according to the root canal instrumentation/filling techniques. Group 1 consisted of specimens in which canal preparation was completed using a crown-down technique and then filled with the Thermafil system (TF group); Group 2 consisted of specimens in which canal preparation was completed using a step-back technique and lateral condensation (LC group). Following root-end resection and ultrasonic cavity preparation, the samples were further divided into three subgroups (n = 24) for root-end filling with IRM, sEBA or MTA. The ultrasonic preparation time was recorded. Eight teeth were kept as positive and 12 as negative controls. Following immersion in Indian ink for 7 days, all resected root surfaces were evaluated for the presence of microcracks and the cross-sectional area of root-end surface and root-end filling were measured to evaluate the thickness of the dentinal walls. Thereafter, the samples were sectioned longitudinally so as to assess the depth of dye penetration and marginal adaptation of root-end fillings. Negative controls longitudinally sectioned were used to describe microstructural characteristics of the root-end filling materials using scanning electron microscopic (SEM) techniques. Results, Although the thickness of dentinal walls between groups 1 and 2 was similar, the ultrasonic preparation time and number of microcracks were significantly higher (P < 0.001) in the TF group. Both groups had a significant correlation between microcracks and ultrasonic preparation time (P < 0.001). sEBA and IRM had better adaptation and less leakage compared with MTA. A SEM analysis displayed microstructural differences between the root-end filling materials. Conclusion, Microcracks can occur independently of the thickness of dentinal walls and may be associated with the prolonged ultrasonic preparation time required for the removal of the root filling during root-end cavity preparation. Although sEBA and IRM had better behaviour than MTA regarding microleakage and marginal adaptation, it is possible that exposure of MTA to a water-soluble dye before achieving full set and its porous microstructure contributed to the results. [source] Imaging of root canal fillings: a comparison of subjective image quality between limited cone-beam CT, storage phosphor and film radiographyINTERNATIONAL ENDODONTIC JOURNAL, Issue 3 2007E. So Abstract Aim, To compare the subjective quality of limited cone-beam computed tomography (LCBCT), storage phosphor plate (SPP) and F-speed film images for the evaluation of length and homogeneity of root fillings. Methodology, Root canals of 17 extracted permanent mandibular incisor teeth were filled. With the teeth placed in their jaws, images were obtained with Accu-I-Tomo LCBCT, Digora® Optime image plate system and F-speed film using exposure parameters yielding ,clinically' acceptable density and contrast. Three radiologists and three endodontists independently rated the quality of all images in respect to homogeneity and the length of root fillings using a 3-graded scale. Evaluations were undertaken in two sessions. In the first, the coronal LCBCT images were not included. In the second, both coronal and sagittal LCBCT images were rated along with F-speed film and SPP images. Results were compared using the Friedman test (P < 0.05). Pair-wise comparisons of systems were completed using the Wilxocon signed-ranks test (P < 0.05). Kappa was used to measure interobserver agreement. Results, Digora images were rated superior, consecutively followed by F-speed films and LCBCT images, for the evaluation of both homogeneity and length of root fillings in both the evaluation sessions (P < 0.05). Kappa ranged from slight to moderate for the length evaluation of root fillings and from poor to fair for the evaluation of homogeneity of root fillings. Conclusion, Image quality of storage phosphor images was subjectively as good as conventional film images and superior to LCBCT images for the evaluation of both homogeneity and length of root fillings in single-rooted teeth. [source] Use of a molar clamp to isolate two adjacent single-rooted teeth: a clinical aidINTERNATIONAL ENDODONTIC JOURNAL, Issue 7 2004K. L. Chen Abstract Aim, To emphasize the importance of rubber dam isolation in root canal treatment and to present a technique to simultaneously isolate two single-rooted teeth using a molar clamp. Summary, Isolation of two adjacent teeth with inadequate tooth structure is a challenge. The split-dam technique or using two clamps have drawbacks. This report presents a technique to simultaneously isolate two adjacent single-rooted teeth that are difficult to isolate by conventional methods. Its advantages are efficiency, reduction of radiation exposure, better access, good visibility and isolation. Key learning points, ,,The basis of this technique is to isolate two teeth as two roots of a molar tooth. ,,The indications for this technique are two adjacent prepared crowns and crownless roots. ,,The appropriate molar clamp can be selected on the basis of the mesial,distal clamp jaw distance being equal to the mesial,distal spacing of the two roots. The buccal,lingual jaw distance of the clamp should be smaller than the dimension of the roots to provide adequate retention. [source] Accuracy of the Justy II Apex locator in determining working length in simulated horizontal and vertical fracturesINTERNATIONAL ENDODONTIC JOURNAL, Issue 3 2004M. Azabal Abstract Aim, To study the effectiveness of an electronic apex locator (EAL; Justy II; Yoshida Dentcraft, Tokyo, Japan) in locating simulated horizontal and vertical fractures in single roots. Methodology, An EAL was used to measure the distance within the canal of horizontal (n = 31) and vertical (n = 31) fractures, created with a disk in single-rooted teeth. Accuracy of the EAL was evaluated by comparing the measurements with those made using a size 10 file. Data were analysed with the non-parametric Passing and Bablok method. Results, For simulated horizontal fractures, the EAL measured exactly the same length as a size 10 file, without constant or proportional errors. In vertical simulated fractures, the EAL measured (on average) with a constant error of 7.5 mm shorter than the size 10 file; the difference had a wide confidence interval (,72.3 to 2.6 mm). Conclusions, In this laboratory study, the Justy II EAL was able to determine accurately the position of simulated horizontal fractures, but was unreliable when measuring simulated vertical fractures. [source] Evaluation of root-end cavity preparation using ultrasonic retrotipsINTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2003H. Ishikawa Abstract Aim, To evaluate and compare the efficiency of root-end preparations using ultrasonic retrotips coated with diamond and zirconium nitride. Methodology, Eighty-five extracted single-rooted teeth were root filled, and then resected 3 mm from their apices. Root-end cavities were prepared with KiS (zirconium nitride-coated retrotip), CT-5 (stainless steel tip) or diamond-coated (DC) ultrasonic retrotips, and 10 teeth served as controls. Thirty teeth were used for evaluation of the time required to prepare the root-end cavity, the number of microcracks produced on the resected surface and the number of dentinal tubule openings on the root-canal wall using scanning electron microscope (SEM) images. A further 55 teeth were used for evaluation of dye penetration following filling of the root-end cavities with Super EBA. The degree of dye penetration in millimetres was measured under the microscope after 7 days of immersion in India ink. Statistical analyses were performed using the one-way anova and Scheffe's F -test as the post hoc test. Results, There was no significant difference in the number of microcracks and dentinal tubule openings present in the root apices prepared by the three retrotips. The time required for root-end cavity preparation using the DC retrotip was significantly less than that using the other groups (P < 0.01). Positive controls showed dye penetration throughout the length of the root-end cavity, and negative controls showed no dye penetration. There was no significant difference between the three experimental groups in dye penetration. Conclusions, In this laboratory study, the time required to prepare root-end cavities using KiS retrotips was the same as that using CT-5 retrotips, and longer than that using DC retrotips. There was no significant difference in the number of microcracks or dye penetration between the three kinds of retrotips. [source] Evaluation of t-PA, PAI-2, IL-1, and PGE2 in gingival crevicular fluid of rheumatoid arthritis patients with periodontal diseaseJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 9 2006Abstract Aims: This study was undertaken to compare periodontal conditions, gingival crevicular fluid (GCF) levels of tissue-type plasminogen activator (t-PA), its inhibitor plasminogen activator inhibitor-2 (PAI-2), interleukin-1, (IL-1,), prostaglandin E2 (PGE2) in rheumatoid arthritis (RA) patients and control groups. Methods: Twenty-three RA patients, 17 systemically healthy patients with periodontal disease (PD), and 17 systemically and periodontally healthy subjects were recruited. GCF samples were obtained from two single-rooted teeth. Full-mouth clinical periodontal measurements were recorded at six sites/tooth. GCF samples were analysed using relevant ELISA kits. Data were tested statistically by appropriate tests. Results: Total amounts of t-PA, PAI-2 and PGE2 in GCF samples of the healthy control group were significantly lower than the other groups (p<0.05). The RA group exhibited a higher total amount of t-PA in GCF samples than the PD group (p<0.05). PAI-2, IL-1, and PGE2 total amounts were similar in RA and PD groups (p>0.05). Conclusion: The coexistence of RA and periodontitis does not seem to affect clinical periodontal findings or systemic markers of RA. Similar inflammatory mediator levels in RA and PD groups, despite the long-term usage of corticosteroids, non-steroidal anti-inflammatory drugs, suggest that RA patients may have a propensity to overproduce these inflammatory mediators. [source] Comparative effectiveness of hand and ultrasonic instrumentations in root surface planing in vitroJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2004Mahmood Khosravi Abstract Background/aims: A variety of techniques are employed for planing and scaling of the superficial root surfaces, of which hand and ultrasonic instrumentations have been preferentially used in routine periodontics clinics. This study was undertaken to compare the effectiveness of ultrasonic scalers and hand curettes in facilitating fibroblast attachment to the scaled root surfaces. Materials and Methods: Sixteen patients with periodontally involved teeth and nine subjects without periodontal diseases (control subjects) were selected. Two single-rooted teeth were extracted from each subject. Mesial and distal surfaces of teeth were selected in treated and untreated groups, respectively. The mesial surface of each tooth was randomly chosen to be treated either by hand curettes or ultrasonic instrumentation. The degree of cell attachment on the root surfaces of treated and untreated groups from control subjects and patients was then determined by the use of a gingival fibroblast line established and employed at early passages. The attachment and proliferation of gingival fibroblasts on the root surfaces were evaluated using neutral red assay and scanning electron microscopy (SEM). Results: Fibroblast survival and proliferation on the surfaces of untreated periodontally involved roots were found to be significantly lower compared with control untreated surfaces (p<0.0001) or treated surfaces from patients (p<0.0001). No significant difference, however, was observed between root surfaces treated either by hand curettes or ultrasonic scalers. Conclusion: These results indicate the beneficial effectiveness of both techniques in root treatment and planing. [source] Fracture Resistance of Endodontically Treated Teeth Restored with Three Different Prefabricated Esthetic PostsJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 1 2003PAULO C. A. MACCARI DDS ABSTRACT Purpose: This study was undertaken to evaluate the role of composition of prefabricated esthetic posts in fracture resistance of endodontically treated teeth in vitro. Materials and Methods: Thirty human, single-rooted teeth (maxillary central incisors and canines) with similar root dimensions, extracted for therapeutic reasons, were used in this study. The crowns were removed below the cementoenamel junction to obtain a standard root length of 17 mm. The roots were endodontically treated following the conventional manual technique and randomly assigned to three groups (n = 10) according to the post used: Aestheti-Post, Bisco, Schaumberg, Illinois; FibreKor Post, Jeneric/Pentron, Wallingford, Connecticut; and CosmoPost, Ivoclar Vivadent, Schaan, Liechtenstein. The root canals were rendered patent, and the root preparations were standardized through flaring with the manufacturers' drills included in the respective kits. The posts were cemented with an adhesive system and a resin cement (All-Bond 2 and C & B, Bisco, respectively), according to the manufacturers' directions. Composite resin (Tetric Ceram, Ivoclar Vivadent) crowns were built up using a preformed polyester matrix, and the specimens were mounted in metallic rings with cold-cure acrylic resin and kept in saline solution at 4°C for 24 hours. Fracture resistance was then determined using an EMIC DL-2000 universal testing machine. The crosshead speed was 0.5 mm/min with the 45-degree compressing load at the middle third of the crown. Data were analyzed using one-way analysis of variance and Tukey'stest (p<.001). Results: Mean fracture resistance was as follows: Aestheti-Post, 83.5 kgf; FibreKor Post, 85.7 kgf; and CosmoPost, 36.5 kgf. The fracture strength of CosmoPost was significantly lower than that of the other posts. Teeth restored with CosmoPost had post fractures, and in three specimens, those were associated with root fractures. Teeth restored with the other two posts presented fractures on the composite crowns. CLINICAL SIGNIFICANCE Compared with ceramic posts, carbon-fiber and glass-fiber prefabricated esthetic posts provide endodontically treated teeth higher fracture resistance. [source] The Retention of Cast Metal Dowels Fabricated by Direct and Indirect TechniquesJOURNAL OF PROSTHODONTICS, Issue 1 2010MDentSci, Wael M. Al-Omari BDS Abstract Purpose: To explore the effect of fabrication technique, cement type, and cementation procedure on retention of cast metal dowels. Methods and Materials: Eighty intact single-rooted teeth were selected. The clinical crown was removed at the cementoenamel junction level. Each root was prepared to receive a cast metal dowel of 10-mm length and 1.45 mm in diameter. The 80 specimens were divided into two major groups of 40 based on fabrication technique (direct and indirect). Each group was further divided into four subgroups of ten based on the cement type (zinc phosphate and glass ionomer), and cementation procedure (with and without lentulo spiral). The dowels were subjected to a constantly increasing tensile force, in a universal Instron testing machine, at crosshead speed of 5 mm/min until failure. Results: The most significant factor to affect retention was the cementation procedure, as cementation with lentulo spiral produced greater retention than cementation without the use of lentulo spiral (p < 0.05); however, there seems to be a close interaction between fabrication technique, cement type, and cementation procedure (p= 0.051). The least retentive group was the one fabricated by direct technique, cemented with zinc phosphate without the use of lentulo spiral. Conclusion: Fabrication technique does not affect retention of cast dowels, except when zinc phosphate was the luting agent and placed in the canal space without using a lentulo spiral. The cementation procedure had a significant effect on retention; thus, it is recommended that cementation should be done using the lentulo spiral. [source] | ||||||||||