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Wang W, Yu X, Xia M, Wang D, Wu J, Hu J, Yan S, Xue M. Effects of crystallization temperature and cooling rate on the polymorphism of
trans
‐1,
4‐polyisoprene
vulcanizate. J Appl Polym Sci 2022. [DOI: 10.1002/app.53202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Wenjun Wang
- Key Laboratory of Rubber‐Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber‐plastics Qingdao University of Science & Technology Qingdao China
| | - Xinyu Yu
- Key Laboratory of Rubber‐Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber‐plastics Qingdao University of Science & Technology Qingdao China
| | - Mingchen Xia
- Key Laboratory of Rubber‐Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber‐plastics Qingdao University of Science & Technology Qingdao China
| | - Dongdong Wang
- Key Laboratory of Rubber‐Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber‐plastics Qingdao University of Science & Technology Qingdao China
| | - Jinghua Wu
- Key Laboratory of Rubber‐Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber‐plastics Qingdao University of Science & Technology Qingdao China
| | - Jian Hu
- Key Laboratory of Rubber‐Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber‐plastics Qingdao University of Science & Technology Qingdao China
| | - Shouke Yan
- Key Laboratory of Rubber‐Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber‐plastics Qingdao University of Science & Technology Qingdao China
| | - Meiling Xue
- Key Laboratory of Rubber‐Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber‐plastics Qingdao University of Science & Technology Qingdao China
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Mehrotra A, Gutte N, Mishra R, Ughade S, Nanditha SK, Shankar. Sealing ability of different obturating techniques in apically separated rotary files: An In Vitro study. J Pharm Bioallied Sci 2022; 14:S884-S887. [PMID: 36110826 PMCID: PMC9469406 DOI: 10.4103/jpbs.jpbs_911_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 03/07/2022] [Indexed: 11/08/2022] Open
Abstract
Aim: Testing whether two sealant systems (cold laterally compacted gutta-percha and Obtura II) can be used with extraction across two apically separated rotational nickel-titanium files was the primary objective of this study (RACE and K3). Materials and Methods: Both the positive and negative control teeth were randomly distributed among 62 mandibular premolars to create two groups of 30 each. Following the RACE and K3 approaches, four subgroups were created from the roots. Subgroups A1, B1, and A2, B2 (n = 10 each) were formed in the apical thirds of the canal at 3 mm from the tip. There was no division of instruments between groups A3, B3, B4, and A4. When it came to obturation, the Obtura II method was used for A2, A4, B2, B4, and A1, A3. A dye extraction process was employed to determine whether the specimens had been obliterated. Analysis of variance (ANOVA), Student t test (two-tailed, independent), and Leven's test were used to ascertain the values for each of the study groups. Results: Group A1 had a substantially lower leakage rate than group B1. Groups A2, B2 and A3, B3 had no statistically significant differences. Group A4 had a substantially lower leakage rate than group B4. Conclusion: Even when the cracked NiTi rotary system was not present, Obtura II-obturated groups had less leakage than the lateral condensation approach.
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Wei X, Peng P, Peng F, Dong J. Natural Polymer Eucommia Ulmoides Rubber: A Novel Material. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:3797-3821. [PMID: 33761246 DOI: 10.1021/acs.jafc.0c07560] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
As the second natural rubber resource, Eucommia ulmoides rubber (EUR) from Eucommia ulmoides Oliver is mainly composed of trans-1,4-polyisoprene, which is the isomer of natural rubber cis-1,4-polyisoprene from Hevea brasiliensis. In the past few years, the great potential application of EUR has received increasing attention, and there is a growing awareness that the natural polymer EUR could become an emerging research topic in field of the novel materials due to its unique and excellent duality of both rubber and plastic. To gain insight into its further development, in this review, the extraction, structure, physicochemical properties, and modification of EUR are discussed in detail. More emphasis on the potential applications in the fields of the environment, agriculture, engineering, and biomedical engineering is summarized. Finally, some insights into the challenges and perspectives of EUR are also suggested.
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Affiliation(s)
- Xingneng Wei
- College of Forestry, Northwest A&F University, Yangling 712100, China
| | - Pai Peng
- College of Forestry, Northwest A&F University, Yangling 712100, China
| | - Feng Peng
- College of Materials Science and Technology, Beijing Forestry University, Beijing 100083, China
| | - Juane Dong
- College of Life Sciences, Northwest A&F University, Yangling 712100, China
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Kim JC, Moe MMK, Kim SK. A micro-computed tomographic evaluation of root canal filling with a single gutta-percha cone and calcium silicate sealer. Restor Dent Endod 2020; 45:e18. [PMID: 32483535 PMCID: PMC7239679 DOI: 10.5395/rde.2020.45.e18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 12/15/2019] [Accepted: 12/19/2019] [Indexed: 11/24/2022] Open
Abstract
Objectives The purpose of this study was to evaluate the void of root canal filling over time when a calcium silicate sealer was used in the single gutta-percha cone technique. Materials and Methods Twenty-four J-shaped simulated root canals and twenty-four palatal root canals from extracted human maxillary molars were instrumented with ProFile Ni-Ti rotary instruments up to size 35/0.06 or size 40/0.06, respectively. Half of the canals were filled with Endoseal MTA and the other half were with AH Plus Jet using the single gutta-percha cone technique. Immediately after and 4 weeks after the root canal filling, the samples were scanned using micro-computed tomography at a resolution of 12.8 μm. The scanned images were reconstructed using the NRecon software and the void percentages were calculated using the CTan software, and statistically analyzed by 1-way analysis of variance, paired t-test and Tukey post hoc test. Results After 4 weeks, there were no significant changes in the void percentages at all levels in both material groups (p > 0.05), except at the apical level of the AH Plus Jet group (p < 0.05) in the simulated root canal showing more void percentage compared to other groups. Immediately after filling the extracted human root canals, the Endoseal MTA group showed significantly less void percentage compared to the AH Plus Jet group (p < 0.05). Conclusions Under the limitations of this study, the Endoseal MTA does not seem to reduce the voids over time.
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Affiliation(s)
- Jong Cheon Kim
- Department of Conservative Dentistry, School of Dentistry, Kyungpook National University, Daegu, Korea
| | - Maung Maung Kyaw Moe
- Department of Conservative Dentistry, University of Dental Medicine, Mandalay, Myanmar
| | - Sung Kyo Kim
- Department of Conservative Dentistry, School of Dentistry, Kyungpook National University, Daegu, Korea
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Hsu YH, Wang HH, Shen YK, Gutmann JL, Hsieh SC. Thermal behavior and viscoelastic properties of gutta-percha used for back-filling the root canal. J Dent Sci 2020; 15:28-33. [PMID: 32256997 PMCID: PMC7109509 DOI: 10.1016/j.jds.2019.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/16/2019] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND/PURPOSE In clinical operations, qualitative differences in the texture and operational feeling of the regular type and soft type back-filled gutta-percha are readily discernible. This study aimed to investigate and compare the thermal behavior and physical properties of the two gutta-percha materials. MATERIALS AND METHODS The chemical compositions of regular and soft type Gutta-Percha Obturator® pellets were examined via energy dispersive X-ray spectroscopy. The thermal behaviors of the pellets during heating and cooling were evaluated using a differential scanning calorimeter. Finally, the viscoelastic properties of the two materials during cooling were assessed using a modular compact rheometer. RESULTS The soft type gutta-percha contained a greater atomic percentage of zinc than the regular type material. In addition, the soft type gutta-percha exhibited exothermic peaks during cooling, whereas the regular type gutta-percha did not. The two materials exhibited different viscoelastic behaviors under cooling. In particular, the rate of change of the loss factor for the soft type gutta-percha was more than that of the regular type gutta-percha at temperature lower than 80°C. CONCLUSION The soft type gutta-percha underwent significant crystallization during cooling, and therefore exhibited pronounced volume shrinkage. Furthermore, the soft type gutta-percha underwent a greater rate of change in viscoelasticity under cooling than the regular type gutta-percha, and exhibited poorer physical stability. Consequently, in the back-packing procedure, soft type gutta-percha must be compacted more often over time than regular type gutta-percha to ensure the same quality of root canal obturation.
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Affiliation(s)
- Yung-Hao Hsu
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Dentistry, Taipei Municipal Wan-Fang Hospital, Taipei, Taiwan
| | - Hsin-Hui Wang
- Department of Dentistry, Taipei Municipal Wan-Fang Hospital, Taipei, Taiwan
| | - Yung-Kang Shen
- School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
| | - James L. Gutmann
- Professor Emeritus, Texas A&M University College of Dentistry, Dallas, TX, USA
| | - Sung-Chih Hsieh
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Dentistry, Taipei Municipal Wan-Fang Hospital, Taipei, Taiwan
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Roberts HW, Kirkpatrick TC, Bergeron BE. Thermal analysis and stability of commercially available endodontic obturation materials. Clin Oral Investig 2017; 21:2589-2602. [PMID: 28185092 DOI: 10.1007/s00784-017-2059-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 01/23/2017] [Indexed: 11/28/2022]
Abstract
OBJECTIVES The purpose of this study was to evaluate the thermal stability of 23 commercially-available endodontic obturation materials. MATERIALS AND METHODS Specimens (n = 10) were sealed in aluminum differential scanning calorimetry (DSC) crucibles and subjected to thermal scan series consisting of a 25 to 70 °C at 5 °C/min followed by a rapid increase to 230 °C, followed by a second scan from 25 to 70 °C at 5 °C/min. The first scan evaluated the materials as-received followed by a worse-case-scenario thermal challenge simulating temperatures involved with warm vertical condensation obturation techniques. The second thermal scan observed any phase changes from the high temperature challenge. This two-scan process was repeated twice to observe changes encountered by repeat high heat exposure during obturation. Mean thermal enthalpies were analyzed with Kruskal-Wallis and Games-Howell post-hoc test. (p = 0.05). RESULTS Thermal behavior was material dependent. During the first thermal scan, materials typically demonstrated broad endothermic enthalpy curves suggesting either a gutta-percha phase mixture and/or an alpha crystalline phase. The first high-heat challenge produced definitive alpha/beta thermal phase signatures usually associated with gutta-percha. Changes in beta-phase enthalpies were noted with Therarmafil Plus and UltraFil Firmset while increase in alpha-phases was observed with GuttaCore, K3, Lexicon, and Schein Accessory Points. CONCLUSIONS Commercial endodontic gutta-percha obturation materials displayed thermal characteristics that were material dependent. However, all demonstrated stability at temperatures in excess to that experienced during warm vertical condensation techniques. CLINICAL RELEVANCE The gutta-percha obturation materials evaluated in this evaluation can be used successfully in warm vertical condensation techniques without fear of degradation.
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Affiliation(s)
- H W Roberts
- Graduate Dental Research, 81 Dental Squadron, 606 Fisher Street, Keesler Air Force Base, Biloxi, MS, 39534, USA.
| | - T C Kirkpatrick
- Advanced Education in Endodontics, 81 Dental Squadron, Keesler Air Force Base, Biloxi, MS, USA
| | - B E Bergeron
- Advanced Education in Endodontics, Georgia Regents University School of Dental Medicine, Augusta, GA, USA
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Mensch K, Simonffy L, Dombi C, Szabó BT, Varga J, Juhasz A, Dobo-Nagy C. Endodontic and microsurgical treatments of maxillary lateral incisor dens invaginatus in combination with cone-beam-computed tomography fusion imaging. Oral Radiol 2016. [DOI: 10.1007/s11282-016-0257-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Intraoral Temperature Triggered Shape-Memory Effect and Sealing Capability of A Transpolyisoprene-Based Polymer. Polymers (Basel) 2015. [DOI: 10.3390/polym7111512] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Trope M, Bunes A, Debelian G. Root filling materials and techniques: bioceramics a new hope? ACTA ACUST UNITED AC 2015. [DOI: 10.1111/etp.12074] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Tsukada G, Tokuda M, Torii M. Temperature Triggered Shape Memory Effect of Transpolyisoprene-based Polymer. J Endod 2014; 40:1658-62. [DOI: 10.1016/j.joen.2014.05.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 05/02/2014] [Accepted: 05/08/2014] [Indexed: 10/25/2022]
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Moon HJ, Lee JH, Ahn JH, Song HJ, Park YJ. Temperature-dependent rheological property changes of thermoplastic gutta-percha root filling materials. Int Endod J 2014; 48:556-63. [DOI: 10.1111/iej.12349] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 07/26/2014] [Indexed: 11/30/2022]
Affiliation(s)
- H. J. Moon
- Department of Dental Materials and Medical Research Center for Biomineralization Disorders; School of Dentistry; Chonnam National University; Gwangju South Korea
| | - J. H. Lee
- Department of Dental Materials and Medical Research Center for Biomineralization Disorders; School of Dentistry; Chonnam National University; Gwangju South Korea
| | - J. H. Ahn
- Department of Dental Materials and Medical Research Center for Biomineralization Disorders; School of Dentistry; Chonnam National University; Gwangju South Korea
| | - H. J. Song
- Department of Dental Materials and Medical Research Center for Biomineralization Disorders; School of Dentistry; Chonnam National University; Gwangju South Korea
| | - Y. J. Park
- Department of Dental Materials and Medical Research Center for Biomineralization Disorders; School of Dentistry; Chonnam National University; Gwangju South Korea
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Lottanti S, Tauböck TT, Zehnder M. Shrinkage of backfill gutta-percha upon cooling. J Endod 2014; 40:721-4. [PMID: 24767571 DOI: 10.1016/j.joen.2013.09.043] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/22/2013] [Accepted: 09/26/2013] [Indexed: 11/28/2022]
Abstract
INTRODUCTION The temperature and related shrinking kinetics of gutta-percha injected from heat guns are not known; therefore, we investigated them in this study. METHODS The temperatures of 3 different backfill gutta-percha brands extruded from 3 commercially available heat guns set to 200°C were studied. To validate the results, temperature development of 1 gutta-percha brand injected from a heat gun during a simulated backfilling procedure was assessed in single-rooted human teeth containing thermocouples in a water bath of 37°C. These values were compared with the counterparts obtained in a tabletop testing device for shrinkage at an ambient temperature of 37°C. Using this device, linear shrinkage upon cooling was assessed for all 3 gutta-percha brands under investigation. Results were compared by parametric statistics (alpha = .05). RESULTS The temperatures of extruded gutta-percha differed significantly (P < .05) between heat guns and gutta-percha brands. Mean temperatures ranging between 57.6° ± 4.5°C and 103.9° ± 7.8°C could be observed with different combinations. The temperature of extruded gutta-percha in tabletop experiments equaled that observed in the root canals. However, the cooling of gutta-percha was (P < .05) faster in the tabletop measuring device compared with the root canal environment. Within the controlled temperature drop from 75°C to 37°C, the total shrinkage differed significantly (P < .05) between the 3 gutta-percha brands under investigation and ranged between 0.96% ± 0.20% and 2.31% ± 0.26% after 10 minutes (P < .05). Shrinking kinetics showed different patterns between the gutta-percha brands. CONCLUSIONS Gutta-percha designed for thermoplastic application shrinks quickly and extensively upon cooling.
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Affiliation(s)
- Silvio Lottanti
- Department of Preventive Dentistry, Periodontology and Cariology, University of Zurich, Center of Dental Medicine, Zurich, Switzerland
| | - Tobias T Tauböck
- Department of Preventive Dentistry, Periodontology and Cariology, University of Zurich, Center of Dental Medicine, Zurich, Switzerland
| | - Matthias Zehnder
- Department of Preventive Dentistry, Periodontology and Cariology, University of Zurich, Center of Dental Medicine, Zurich, Switzerland.
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Rangappa KG, Hegde J, Chikkamallaiah C, Bashetty K, Rashmi K, Kumar KK. Comparative evaluation of the sealing ability of different obturation systems used over apically separated rotary nickel-titanium files: An in vitro study. J Conserv Dent 2013; 16:408-12. [PMID: 24082568 PMCID: PMC3778621 DOI: 10.4103/0972-0707.117502] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 03/08/2013] [Accepted: 05/14/2013] [Indexed: 11/29/2022] Open
Abstract
Aim: The study was designed to investigate the sealing ability of two obturation systems (cold laterally compacted gutta percha and Obtura II) over different apically separated rotary nickel-titanium files (RACE and K3 system) using dye extraction method. Materials and Methods: Sixty-two mandibular premolars were divided into 2 groups of 30 teeth each, and 2 teeth served as negative controls. In Groups A and B, roots were prepared using RACE and K3 system, respectively, and were further subdivided into 4 subgroups. In subgroups A1, B1 and A2, B2 (n = 10 each), files were separated at 3 mm from the tip in apical 3rd of the canal. In subgroups A3, B3 and A4, B4 (n = 5), instruments were not separated. Subgroups A1, A3, B1, B3 and A2, A4, B2, B4 were obturated by lateral condensation method and Obtura II techniques, respectively. The sealing ability of the obturated specimens were tested using dye extraction method. The values for each group were recorded and analysis of variance (ANOVA), Student “t” test (two-tailed, independent), and Leven's test were performed. Results: Group A1 showed significantly less leakage than B1. No statistical significant difference between Groups A2 and B2 and Groups A3 and B3, respectively, were observed. Group A4 showed significantly less leakage than B4. Conclusion: Groups obturated with Obtura II showed less leakage than the lateral condensation technique irrespective of presence or absence of fractured NiTi rotary system.
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Affiliation(s)
| | - Jayshree Hegde
- Department of Conservative Dentistry and Endodontics, The Oxford Dental College, Bangalore, Karnataka, India
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Jaya Ratri P, Tashiro K. Application of the simultaneous measurement system of WAXD, SAXS and transmission FTIR spectra to the study of structural changes in the cold- and melt-crystallization processes of trans-1,4-polyisoprene. Polym J 2013. [DOI: 10.1038/pj.2013.31] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Chen WP, Chen YY, Huang SH, Lin CP. Limitations of Push-out Test in Bond Strength Measurement. J Endod 2013; 39:283-7. [DOI: 10.1016/j.joen.2012.11.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 11/02/2012] [Accepted: 11/06/2012] [Indexed: 11/29/2022]
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Setzer FC, Kataoka SHH, Natrielli F, Gondim-Junior E, Caldeira CL. Clinical diagnosis of pulp inflammation based on pulp oxygenation rates measured by pulse oximetry. J Endod 2012; 38:880-3. [PMID: 22703647 DOI: 10.1016/j.joen.2012.03.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 03/27/2012] [Accepted: 03/27/2012] [Indexed: 10/28/2022]
Abstract
INTRODUCTION The objective of this study was to investigate correlations between pulp oxygenation rates (%SpO(2)) and clinical diagnoses of reversible pulpitis (RP), irreversible pulpitis (IP), or pulp necrosis (PN). METHODS Sixty patients who presented with a tooth with endodontic pathology were grouped according to a clinical diagnosis of either RP (n = 20), IP (n = 20), or PN (n = 20). The clinical diagnosis was based on the patient's dental history, periapical radiographs, clinical inspection, and percussion and thermal sensitivity testing. Pulse oximetry (PO) was used to determine pulp oxygenation rates. For every patient, one additional endodontically treated tooth (negative control [NC], n = 60) and one additional healthy tooth with healthy pulp status (positive control [PC], n = 60) were evaluated. Analysis of variance, the Tukey HSD test, and the Student's t test were used for statistical analysis. RESULTS The mean %SpO(2) levels were as follows: RP: 87.4% (standard deviation [SD] ±2.46), IP: 83.1% (SD ±2.29), PN: 74.6% (SD ±1.96), PC: 92.2% (SD ±1.84), and NC: 0% (SD ±0.0). There were statistically significant differences between RP, IP, and PN compared with NC and PC and between RP, IP, and PN (all P ≤ .01). CONCLUSIONS The evaluation of pulp oxygenation rates by PO may be a useful tool to determine the different inflammatory stages of the pulp to aid in endodontic diagnosis.
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Affiliation(s)
- Frank C Setzer
- Department of Endodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Temperature Changes in Gutta-Percha and Resilon Cones Induced by a Thermomechanical Compaction Technique. J Endod 2009; 35:879-82. [DOI: 10.1016/j.joen.2009.03.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2008] [Revised: 03/04/2009] [Accepted: 03/05/2009] [Indexed: 11/23/2022]
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Miner MR, Berzins DW, Bahcall JK. A comparison of thermal properties between gutta-percha and a synthetic polymer based root canal filling material (Resilon). J Endod 2006; 32:683-6. [PMID: 16793481 DOI: 10.1016/j.joen.2006.01.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Revised: 01/13/2006] [Accepted: 01/15/2006] [Indexed: 10/24/2022]
Abstract
A new polymer-based obturating material, Resilon, has been developed but there have been no studies identifying its thermal properties. The purpose of this study was to compare the melting point, specific heat, enthalpy change with melting and heat transfer between gutta-percha (GP) and Resilon (R). The first three tests were determined using a differential scanning calorimeter and the heat transfer test was determined using a split-tooth model. Results show no significant difference (t test, p > 0.05) between gutta-percha and Resilon for the melting point temperature (GP: 60.01 degrees C; R: 60.57 degrees C). There was a significant difference (t test, p < 0.05) in specific heat capacity (GP: 0.94 J/g degrees C, R: 1.15 J/g degrees C) and endothermic enthalpy change (GP: 10.88 J/g, R: 25.20 J/g) between the two materials. The heat transfer test showed a significant difference (Mann-Whitney, p < 0.05) in temperature increase between gutta-percha and Resilon within 3 mm of the heat source.
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Affiliation(s)
- Marcus R Miner
- Department of Endodontics, Marquette University, School of Dentistry, Milwaukee, Wisconsin 53233, USA.
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