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Kim HJ, Oh S, Kwon J, Choi KK, Jang JH, Kim DS. Desensitizing efficacy of a universal dentin adhesive containing mesoporous bioactive glass on dentin hypersensitivity: a randomized clinical trial with a split-mouth model. Sci Rep 2024; 14:13926. [PMID: 38886498 PMCID: PMC11183245 DOI: 10.1038/s41598-024-64404-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 06/07/2024] [Indexed: 06/20/2024] Open
Abstract
This split-mouth blinded randomized controlled study compared the efficacy of a desensitizing agent with oxalate/resin polymer and a universal adhesive containing mesoporous bioactive glass (MBG) for dentin hypersensitivity (DH) relief, using Schiff sensitivity score (SSS) and visual analog scale (VAS). Split quadrants containing teeth with DH were treated with either MS Coat ONE or Hi-Bond Universal with MBG as the functional additive. Assessments at baseline, immediately post-application, and at 1- and 2-week follow-ups used standardized stimulus protocols (air, cold, and acid). The SSS difference was the primary outcome, while the VAS difference was the secondary outcome. A mixed linear effect model performed statistical analysis. Immediate DH reduction occurred in response to air stimuli, with a significant decrease in Group HB than in Group MS (p = 0.0178). Cold stimulus reduction exhibited a gradual cumulative effect, with consistently greater reductions in Group HB than in Group MS (p ≤ 0.0377). Both groups effectively managed acidic stimuli, with no significant differences (p > 0.05). The VAS scores decreased gradually over the follow-up period (p < 0.0001). This study highlights the differential efficacy of treatments for various DH triggers and recommends specific approaches based on different stimulus types. The universal adhesive containing MBG demonstrated DH relief potential, promising efficacy identical to or superior to that of a dedicated desensitizing agent. Further research exploring the long-term efficacy and underlying mechanisms is warranted. The universal adhesive containing MBG can be adopted as an in-office desensitizing agent for DH relief. The desensitizing efficacy of universal adhesive matches or surpasses dedicated agents for air and cold stimuli.
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Affiliation(s)
- Hyun-Jung Kim
- Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, 24 Kyungheedae-ro, Dongdaemoon-gu, Seoul, 02453, South Korea
| | - Soram Oh
- Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, 24 Kyungheedae-ro, Dongdaemoon-gu, Seoul, 02453, South Korea
| | - Jiyoung Kwon
- Department of Conservative Dentistry, Kyung Hee University Dental Hospital, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, 02447, South Korea
| | - Kyoung-Kyu Choi
- Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, 24 Kyungheedae-ro, Dongdaemoon-gu, Seoul, 02453, South Korea
| | - Ji-Hyun Jang
- Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, 24 Kyungheedae-ro, Dongdaemoon-gu, Seoul, 02453, South Korea.
| | - Duck-Su Kim
- Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, 24 Kyungheedae-ro, Dongdaemoon-gu, Seoul, 02453, South Korea.
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Staicu AN, Țuculină MJ, Cumpătă CN, Rîcă AM, Beznă MC, Popa DL, Popescu AD, Diaconu OA. A Finite Element Method Study on a Simulation of the Thermal Behaviour of Four Methods for the Restoration of Class II Cavities. J Funct Biomater 2024; 15:86. [PMID: 38667543 PMCID: PMC11050888 DOI: 10.3390/jfb15040086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/28/2024] Open
Abstract
The possibility of dental pulp damage during dental procedures is well known. According to studies, during finishing and polishing without cooling, temperatures of up to 140 °C or more can be generated. There are many studies that have analysed the influence of the finishing and polishing of fillings on the mechanical parameters, but the analysis of thermal parameters has led to uncertain results due to the difficulty of performing this in vivo. Background: We set out to conduct a study, using the finite element method, to determine the extent to which the type of class II cavity and the volume of the composite filling influence the duration of heat transfer to the pulp during finishing and polishing without cooling. Materials and Methods: A virtual model of an upper primary molar was used, with a caries process located on the distal aspect, in which four types of cavities were digitally prepared: direct access, horizontal slot, vertical slot and occlusal-proximal. All four cavity types were filled using a Filtek Supreme XT nanocomposite. Results: The study showed that the filling volume almost inversely proportionally influences the time at which the dental pulp reaches the critical temperature of irreversible damage. The lowest duration occurred in occlusal-distal restorations and the highest in direct access restorations. Conclusions: based on the results of the study, a working protocol can be issued so that finishing and polishing restorations without cooling are safe for pulpal health.
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Affiliation(s)
- Adela Nicoleta Staicu
- Department of Endodontics, Faculty of Dentistry, University of Medicine and Pharmacy of Craiova, 200349 Craiova, Romania; (A.N.S.); (A.M.R.); (A.D.P.); (O.A.D.)
| | - Mihaela Jana Țuculină
- Department of Endodontics, Faculty of Dentistry, University of Medicine and Pharmacy of Craiova, 200349 Craiova, Romania; (A.N.S.); (A.M.R.); (A.D.P.); (O.A.D.)
| | - Cristian Niky Cumpătă
- Department of maxillofacial surgery, Faculty of Dental Medicine, University Titu Maiorescu of Bucharest, 67A Gheorghe Petrascu Str., 031593 Bucharest, Romania
| | - Ana Maria Rîcă
- Department of Endodontics, Faculty of Dentistry, University of Medicine and Pharmacy of Craiova, 200349 Craiova, Romania; (A.N.S.); (A.M.R.); (A.D.P.); (O.A.D.)
| | - Maria Cristina Beznă
- Department of Pathophysiology, Faculty of Dentistry, University of Medicine and Pharmacy of Craiova, 200349 Craiova, Romania;
| | - Dragoș Laurențiu Popa
- Department of Automotive, Transportation and Industrial Engineering, Faculty of Mechanics, University of Craiova, 200478 Craiova, Romania;
| | - Alexandru Dan Popescu
- Department of Endodontics, Faculty of Dentistry, University of Medicine and Pharmacy of Craiova, 200349 Craiova, Romania; (A.N.S.); (A.M.R.); (A.D.P.); (O.A.D.)
| | - Oana Andreea Diaconu
- Department of Endodontics, Faculty of Dentistry, University of Medicine and Pharmacy of Craiova, 200349 Craiova, Romania; (A.N.S.); (A.M.R.); (A.D.P.); (O.A.D.)
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Ronan EA, Nagel M, Emrick JJ. The anatomy, neurophysiology, and cellular mechanisms of intradental sensation. FRONTIERS IN PAIN RESEARCH 2024; 5:1376564. [PMID: 38590718 PMCID: PMC11000636 DOI: 10.3389/fpain.2024.1376564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 03/11/2024] [Indexed: 04/10/2024] Open
Abstract
Somatosensory innervation of the oral cavity enables the detection of a range of environmental stimuli including minute and noxious mechanical forces. The trigeminal sensory neurons underlie sensation originating from the tooth. Prior work has provided important physiological and molecular characterization of dental pulp sensory innervation. Clinical dental experiences have informed our conception of the consequence of activating these neurons. However, the biological role of sensory innervation within the tooth is yet to be defined. Recent transcriptomic data, combined with mouse genetic tools, have the capacity to provide important cell-type resolution for the physiological and behavioral function of pulp-innervating sensory neurons. Importantly, these tools can be applied to determine the neuronal origin of acute dental pain that coincides with tooth damage as well as pain stemming from tissue inflammation (i.e., pulpitis) toward developing treatment strategies aimed at relieving these distinct forms of pain.
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Affiliation(s)
- Elizabeth A. Ronan
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
| | - Maximilian Nagel
- Sensory Cells and Circuits Section, National Center for Complementary and Integrative Health, Bethesda, MD, United States
| | - Joshua J. Emrick
- Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States
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Lau XE, Liu X, Chua H, Wang WJ, Dias M, Choi JJE. Heat generated during dental treatments affecting intrapulpal temperature: a review. Clin Oral Investig 2023; 27:2277-2297. [PMID: 37022531 PMCID: PMC10159962 DOI: 10.1007/s00784-023-04951-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 03/14/2023] [Indexed: 04/07/2023]
Abstract
INTRODUCTION Heat is generated and transferred to the dentine-pulp complex during various dental procedures, such as from friction during cavity preparations, exothermic reactions during the polymerisation of restorative materials and when polishing restorations. For in vitro studies, detrimental effects are possible when intra-pulpal temperature increases by more than 5.5°C (that is, the intra-pulpal temperature exceeds 42.4°C). This excessive heat transfer results in inflammation and necrosis of the pulp. Despite numerous studies stating the importance of heat transfer and control during dental procedures, there are limited studies that have quantified the significance. Past studies incorporated an experimental setup where a thermocouple is placed inside the pulp of an extracted human tooth and connected to an electronic digital thermometer. METHODS This review identified the opportunity for future research and develop both the understanding of various influencing factors on heat generation and the different sensor systems to measure the intrapulpal temperature. CONCLUSION Various steps of dental restorative procedures have the potential to generate considerable amounts of heat which can permanently damage the pulp, leading to pulp necrosis, discoloration of the tooth and eventually tooth loss. Thus, measures should be undertaken to limit pulp irritation and injury during procedures. This review highlighted the gap for future research and a need for an experimental setup which can simulate pulp blood flow, temperature, intraoral temperature and intraoral humidity to accurately simulate the intraoral conditions and record temperature changes during various dental procedures.
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Affiliation(s)
- Xin Er Lau
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin, 9016, New Zealand
| | - Xiaoyun Liu
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin, 9016, New Zealand
| | - Helene Chua
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin, 9016, New Zealand
| | - Wendy Jingwen Wang
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin, 9016, New Zealand
| | - Maykon Dias
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin, 9016, New Zealand
| | - Joanne Jung Eun Choi
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin, 9016, New Zealand.
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Liu Y, Wang Y, Lou Y, Tian W, Que K. Functional expression of TRPA1 channel, TRPV1 channel and TMEM100 in human odontoblasts. J Mol Histol 2021; 52:1105-1114. [PMID: 34514518 DOI: 10.1007/s10735-021-10018-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 09/07/2021] [Indexed: 01/15/2023]
Abstract
TRPA1 and TRPV1 channels respond to external stimulation as pain mediators and form a complex with a transmembrane protein TMEM100 in some tissues. However, their expression and interaction in dental pulp is unclear. To investigate the functional co-expression of TRPA1 channel, TRPV1 channel and TMEM100 in human odontoblasts (HODs), immunohistochemistry, immunofluorescence staining and Western blot were used to study their co-localization and expression in both native HODs and cultured HOD-like cells. Calcium imaging was used to detect the functional interaction between TRPA1 and TRPV1 channels. Immunohistochemistry and multiple immunofluorescence staining of tooth slices showed positive expression of TRPA1 channel, TRPV1 channel and TMEM100 mainly in the cell bodies of HODs, and TRPA1 channel presented more obvious immunofluorescence in the cell processes than TRPV1 channel and TMEM100. HALO software analysis showed that TRPA1 and TRPV1 channels were positively expressed in most TMEM100+ HODs and these three proteins were strongly correlated in HODs (P < 0.01). The protein expression levels of TRPA1 channel, TRPV1 channel and TMEM100 in HODs showed no significant difference (P > 0.05). Double immunofluorescence staining of cultured HOD-like cells visually demonstrated that TRPA1 and TRPV1 channel were both highly co-localized with TMEM100 with similar expressive intensity. Calcium imaging showed that there was a functional interaction between TRPA1 and TRPV1 channels in HOD-like cells, and TRPA1 channel might play a greater role in this interaction. Overall, we concluded that TRPA1 channel, TRPV1 channel and TMEM100 could be functionally co-expressed in HODs.
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Affiliation(s)
- Yangqiu Liu
- Department of Endodontics, College of Stomatology, Tianjin Medical University, Num22, Road Qixiangtai, Heping District, Tianjin, 300070, China.,Shandong Medical College, Linyi, 276000, Shandong, China
| | - Yu Wang
- Department of Endodontics, College of Stomatology, Tianjin Medical University, Num22, Road Qixiangtai, Heping District, Tianjin, 300070, China.,Stomatological Hospital of Lianyungang, The First People's Hospital of Lianyungang, Lianyungang, 222000, Jiangsu, China
| | - Yaxin Lou
- Department of Endodontics, College of Stomatology, Tianjin Medical University, Num22, Road Qixiangtai, Heping District, Tianjin, 300070, China
| | - Weiping Tian
- Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin, 300070, China.
| | - Kehua Que
- Department of Endodontics, College of Stomatology, Tianjin Medical University, Num22, Road Qixiangtai, Heping District, Tianjin, 300070, China.
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Bernal L, Sotelo-Hitschfeld P, König C, Sinica V, Wyatt A, Winter Z, Hein A, Touska F, Reinhardt S, Tragl A, Kusuda R, Wartenberg P, Sclaroff A, Pfeifer JD, Ectors F, Dahl A, Freichel M, Vlachova V, Brauchi S, Roza C, Boehm U, Clapham DE, Lennerz JK, Zimmermann K. Odontoblast TRPC5 channels signal cold pain in teeth. SCIENCE ADVANCES 2021; 7:7/13/eabf5567. [PMID: 33771873 PMCID: PMC7997515 DOI: 10.1126/sciadv.abf5567] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 02/09/2021] [Indexed: 05/21/2023]
Abstract
Teeth are composed of many tissues, covered by an inflexible and obdurate enamel. Unlike most other tissues, teeth become extremely cold sensitive when inflamed. The mechanisms of this cold sensation are not understood. Here, we clarify the molecular and cellular components of the dental cold sensing system and show that sensory transduction of cold stimuli in teeth requires odontoblasts. TRPC5 is a cold sensor in healthy teeth and, with TRPA1, is sufficient for cold sensing. The odontoblast appears as the direct site of TRPC5 cold transduction and provides a mechanism for prolonged cold sensing via TRPC5's relative sensitivity to intracellular calcium and lack of desensitization. Our data provide concrete functional evidence that equipping odontoblasts with the cold-sensor TRPC5 expands traditional odontoblast functions and renders it a previously unknown integral cellular component of the dental cold sensing system.
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Affiliation(s)
- Laura Bernal
- Department of Anesthesiology, Erlangen University Hospital, Friedrich Alexander University of Erlangen-Nuremberg (FAU), Erlangen, Germany
- Departamento de Biología de Sistemas, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain
| | - Pamela Sotelo-Hitschfeld
- Department of Anesthesiology, Erlangen University Hospital, Friedrich Alexander University of Erlangen-Nuremberg (FAU), Erlangen, Germany
- Institute of Physiology, Faculty of Medicine and Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile
| | - Christine König
- Department of Anesthesiology, Erlangen University Hospital, Friedrich Alexander University of Erlangen-Nuremberg (FAU), Erlangen, Germany
| | - Viktor Sinica
- Department of Anesthesiology, Erlangen University Hospital, Friedrich Alexander University of Erlangen-Nuremberg (FAU), Erlangen, Germany
- Department of Cellular Neurophysiology, Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Amanda Wyatt
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Zoltan Winter
- Department of Anesthesiology, Erlangen University Hospital, Friedrich Alexander University of Erlangen-Nuremberg (FAU), Erlangen, Germany
| | - Alexander Hein
- HHMI, Cardiovascular Division, Boston Children's Hospital, and Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Filip Touska
- Department of Anesthesiology, Erlangen University Hospital, Friedrich Alexander University of Erlangen-Nuremberg (FAU), Erlangen, Germany
- Department of Cellular Neurophysiology, Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Susanne Reinhardt
- Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Dresden, Germany
| | - Aaron Tragl
- Department of Anesthesiology, Erlangen University Hospital, Friedrich Alexander University of Erlangen-Nuremberg (FAU), Erlangen, Germany
| | - Ricardo Kusuda
- Department of Anesthesiology, Erlangen University Hospital, Friedrich Alexander University of Erlangen-Nuremberg (FAU), Erlangen, Germany
| | - Philipp Wartenberg
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - Allen Sclaroff
- Department of Otolaryngology, Washington University School of Medicine, St Louis, MO, USA
| | - John D Pfeifer
- Department of Pathology, Washington University School of Medicine, St Louis, MO, USA
| | - Fabien Ectors
- FARAH Mammalian Transgenics Platform, Liège University, Liège, Belgium
| | - Andreas Dahl
- Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Dresden, Germany
| | - Marc Freichel
- Institute of Pharmacology, University of Heidelberg, Heidelberg, Germany
| | - Viktorie Vlachova
- Department of Cellular Neurophysiology, Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Sebastian Brauchi
- Institute of Physiology, Faculty of Medicine and Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile
- Millennium Nucleus of Ion Channel-associated Diseases (MiNICAD), Santiago, Chile
| | - Carolina Roza
- Departamento de Biología de Sistemas, Facultad de Medicina, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain
| | - Ulrich Boehm
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | - David E Clapham
- HHMI, Cardiovascular Division, Boston Children's Hospital, and Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
| | - Jochen K Lennerz
- Center for Integrated Diagnostics, Department of Pathology, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA.
| | - Katharina Zimmermann
- Department of Anesthesiology, Erlangen University Hospital, Friedrich Alexander University of Erlangen-Nuremberg (FAU), Erlangen, Germany.
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7
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In vivo temperature rise and acute inflammatory response in anesthetized human pulp tissue of premolars having Class V preparations after exposure to Polywave® LED light curing units. Dent Mater 2020; 36:1201-1213. [DOI: 10.1016/j.dental.2020.05.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 05/20/2020] [Accepted: 05/25/2020] [Indexed: 11/20/2022]
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8
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Cotti E, Cairo F, Bassareo P, Fonzar F, Venturi M, Landi L, Parolari A, Franco V, Fabiani C, Barili F, Di Lenarda A, Gulizia M, Borzi M, Campus G, Musumeci F, Mercuro G. Perioperative dental screening and treatment in patients undergoing cardio-thoracic surgery and interventional cardiovascular procedures. A consensus report based on RAND/UCLA methodology. Int J Cardiol 2019; 292:78-86. [DOI: 10.1016/j.ijcard.2019.06.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Cotti E, Cairo F, Bassareo PP, Fonzar F, Venturi M, Landi L, Parolari A, Franco V, Fabiani C, Barili F, Di Lenarda A, Gulizia M, Borzi M, Campus G, Musumeci F, Mercuro G. Perioperative dental screening and treatment in patients undergoing cardiothoracic surgery and interventional cardiovascular procedures. A consensus report based on RAND/UCLA methodology. Int Endod J 2019; 53:186-199. [PMID: 31162683 DOI: 10.1111/iej.13166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Accepted: 05/31/2019] [Indexed: 11/28/2022]
Abstract
AIM To reach a consensus on a consistent strategy to adopt when screening patients for dental/periodontal infections and on the feasibility of providing dental treatment before cardiothoracic surgery, cardiovascular surgery or other cardiovascular invasive procedures. METHODOLOGY A panel of experts from six Italian scientific societies was created. The deliberations of the panel were based on the RAND method. From an initial systematic literature review, it became clear that a consensually validated protocol for the reproducible dental screening of patients awaiting cardiac interventions was considered mandatory by professionals with expertise in the dental, cardiologic and cardiac surgery areas. However, a systematic review also concluded that the treatment options to be provided, their prognosis and timing in relation to the physical condition of patients, had never been defined. Following the systematic review, several fundamental questions were generated. The panel was divided into two working groups each of which produced documents that addressed the topic and which were subsequently used to generate a questionnaire. Each member of the panel completed the questionnaire independently, and then, a panel discussion was held to reach a consensus on how best to manage patients with dental/periodontal infections who were awaiting invasive cardiac procedures. RESULTS A high level of agreement was reached regarding all the items on the questionnaire, and each of the clinical questions formulated were answered. Three tables were created which can be used to generate a useful tool to provide standardized dental/periodontal screening of patients undergoing elective cardiovascular interventions and to summarize both the possible oral and cardiovascular conditions of the patient and the timing available for the procedures considered. CONCLUSIONS Upon publication of this consensus document, the dissemination of the information to a wide dental and cardiac audience should commence. The authors hope that this consensus will become a model for the development of a dedicated protocol, ideally usable by heart and dental teams in the pre-interventional preparation phase.
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Affiliation(s)
- E Cotti
- Department of Conservative Dentistry and Endodontics, University of Cagliari, Cagliari, Italy
| | - F Cairo
- Research Unit in Periodontology and Periodontal Medicine, University of Florence, Florence, Italy
| | - P P Bassareo
- University College of Dublin, Mater Misericordiae University Teaching Hospital, Dublin, Ireland
| | | | | | - L Landi
- Private practice, Verona, Roma, Italy
| | - A Parolari
- Unit of Cardiac Surgery and Translational Researh, IRCCS Policlinico S. Donato, San Donato, Italy
| | | | | | - F Barili
- Department of Cardiac Surgery, S. Croce Hospital, Cuneo, Italy
| | | | - M Gulizia
- Division of Cardiology, Hospital "Garibaldi-Nesima", Catania, Italy
| | - M Borzi
- Department of Cardiovascular Disease, University of Rome Tor Vergata, Rome, Italy
| | - G Campus
- Department of Surgery, Microsurgery and Medicine Sciences, University of Sassari, Sassari, Italy
| | - F Musumeci
- Department of Heart and Vessels, Cardiac Surgery Unit and Heart Transplantation Center, S. Camillo-Forlanini Hospital, Roma, Italy
| | - G Mercuro
- Department of Medical Sciences, University of Cagliari, Cagliari, Italy
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10
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Lee K, Lee BM, Park CK, Kim YH, Chung G. Ion Channels Involved in Tooth Pain. Int J Mol Sci 2019; 20:ijms20092266. [PMID: 31071917 PMCID: PMC6539952 DOI: 10.3390/ijms20092266] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 05/03/2019] [Accepted: 05/03/2019] [Indexed: 01/05/2023] Open
Abstract
The tooth has an unusual sensory system that converts external stimuli predominantly into pain, yet its sensory afferents in teeth demonstrate cytochemical properties of non-nociceptive neurons. This review summarizes the recent knowledge underlying this paradoxical nociception, with a focus on the ion channels involved in tooth pain. The expression of temperature-sensitive ion channels has been extensively investigated because thermal stimulation often evokes tooth pain. However, temperature-sensitive ion channels cannot explain the sudden intense tooth pain evoked by innocuous temperatures or light air puffs, leading to the hydrodynamic theory emphasizing the microfluidic movement within the dentinal tubules for detection by mechanosensitive ion channels. Several mechanosensitive ion channels expressed in dental sensory systems have been suggested as key players in the hydrodynamic theory, and TRPM7, which is abundant in the odontoblasts, and recently discovered PIEZO receptors are promising candidates. Several ligand-gated ion channels and voltage-gated ion channels expressed in dental primary afferent neurons have been discussed in relation to their potential contribution to tooth pain. In addition, in recent years, there has been growing interest in the potential sensory role of odontoblasts; thus, the expression of ion channels in odontoblasts and their potential relation to tooth pain is also reviewed.
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Affiliation(s)
- Kihwan Lee
- Gachon Pain Center and Department of Physiology, College of Medicine, Gachon University, Incheon 406-799, Korea.
| | - Byeong-Min Lee
- Department of Oral Physiology and Program in Neurobiology, School of Dentistry, Seoul National University, Seoul 08826, Korea.
| | - Chul-Kyu Park
- Gachon Pain Center and Department of Physiology, College of Medicine, Gachon University, Incheon 406-799, Korea.
| | - Yong Ho Kim
- Gachon Pain Center and Department of Physiology, College of Medicine, Gachon University, Incheon 406-799, Korea.
| | - Gehoon Chung
- Department of Oral Physiology and Program in Neurobiology, School of Dentistry, Seoul National University, Seoul 08826, Korea.
- Dental Research Institute, Seoul National University, Seoul 03080, Korea.
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11
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Hossain MZ, Bakri MM, Yahya F, Ando H, Unno S, Kitagawa J. The Role of Transient Receptor Potential (TRP) Channels in the Transduction of Dental Pain. Int J Mol Sci 2019; 20:ijms20030526. [PMID: 30691193 PMCID: PMC6387147 DOI: 10.3390/ijms20030526] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 01/18/2019] [Accepted: 01/24/2019] [Indexed: 12/18/2022] Open
Abstract
Dental pain is a common health problem that negatively impacts the activities of daily living. Dentine hypersensitivity and pulpitis-associated pain are among the most common types of dental pain. Patients with these conditions feel pain upon exposure of the affected tooth to various external stimuli. However, the molecular mechanisms underlying dental pain, especially the transduction of external stimuli to electrical signals in the nerve, remain unclear. Numerous ion channels and receptors localized in the dental primary afferent neurons (DPAs) and odontoblasts have been implicated in the transduction of dental pain, and functional expression of various polymodal transient receptor potential (TRP) channels has been detected in DPAs and odontoblasts. External stimuli-induced dentinal tubular fluid movement can activate TRP channels on DPAs and odontoblasts. The odontoblasts can in turn activate the DPAs by paracrine signaling through ATP and glutamate release. In pulpitis, inflammatory mediators may sensitize the DPAs. They could also induce post-translational modifications of TRP channels, increase trafficking of these channels to nerve terminals, and increase the sensitivity of these channels to stimuli. Additionally, in caries-induced pulpitis, bacterial products can directly activate TRP channels on DPAs. In this review, we provide an overview of the TRP channels expressed in the various tooth structures, and we discuss their involvement in the development of dental pain.
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Affiliation(s)
- Mohammad Zakir Hossain
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan.
| | - Marina Mohd Bakri
- Department of Oral and Craniofacial Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Farhana Yahya
- Department of Oral and Craniofacial Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Hiroshi Ando
- Department of Biology, School of Dentistry, Matsumoto Dental University, 1780 Gobara, Hirooka, Shiojiri, Nagano 399-0781, Japan.
| | - Shumpei Unno
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan.
| | - Junichi Kitagawa
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan.
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12
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Thermal analysis of the dentine tubule under hot and cold stimuli using fluid-structure interaction simulation. Biomech Model Mechanobiol 2018; 17:1599-1610. [PMID: 29956062 DOI: 10.1007/s10237-018-1046-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 06/24/2018] [Indexed: 12/14/2022]
Abstract
The objective of this study is to compare the thermal stress changes in the tooth microstructures and the hydrodynamic changes of the dental fluid under hot and cold stimuli. The dimension of the microstructures of eleven cats' teeth was measured by scanning electron microscopy, and the changes in thermal stress during cold and hot stimulation were calculated by 3D fluid-structure interaction modeling. Evaluation of results, following data validation, indicated that the maximum velocities in cold and hot stimuli were - 410.2 ± 17.6 and + 205.1 ± 8.7 µm/s, respectively. The corresponding data for maximum thermal stress were - 20.27 ± 0.79 and + 10.13 ± 0.24 cmHg, respectively. The thermal stress caused by cold stimulus could influence almost 2.9 times faster than that caused by hot stimulus, and the durability of the thermal stress caused by hot stimulus was 71% greater than that by cold stimulus under similar conditions. The maximum stress was on the tip of the odontoblast, while the stress in lateral walls of the odontoblast and terminal fibril was very weak. There is hence a higher possibility of pain transmission with activation of stress-sensitive ion channels at the tip of the odontoblast. The maximum thermal stress resulted from the cold stimulus is double that produced by the hot stimulus. There is a higher possibility of pain transmission in the lateral walls of the odontoblast and terminal fibril by releasing mediators during the cold stimulation than the hot stimulation. These two reasons can be associated with a greater pain sensation due to intake of cold liquids.
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13
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Le Fur-Bonnabesse A, Bodéré C, Hélou C, Chevalier V, Goulet JP. Dental pain induced by an ambient thermal differential: pathophysiological hypothesis. J Pain Res 2017; 10:2845-2851. [PMID: 29290692 PMCID: PMC5736355 DOI: 10.2147/jpr.s142539] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Dental pain triggered by temperature differential is a misrecognized condition and a form of dental allodynia. Dental allodynia is characterized by recurrent episodes of diffuse, dull and throbbing tooth pain that develops when returning to an indoor room temperature after being exposed for a long period to cold weather. The pain episode may last up to few hours before subsiding. Effective treatment is to properly shield the pulpal tissue of the offending tooth by increasing the protective layer of the dentin/enamel complex. This review underscores the difference in dentin hypersensitivity and offers a mechanistic hypothesis based on the following processes. Repeated exposure to significant positive temperature gradients (from cold to warm) generates phenotypic changes of dental primary afferents on selected teeth with subsequent development of a “low-grade” neurogenic inflammation. As a result, nociceptive C-fibers become sensitized and responsive to innocuous temperature gradients because the activation threshold of specific TRP ion channels is lowered and central sensitization takes place. Comprehensive overviews that cover dental innervation and sensory modalities, thermodynamics of tooth structure, mechanisms of dental nociception and the thermal pain are also provided.
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Affiliation(s)
- Anaïs Le Fur-Bonnabesse
- Laboratory of Neurosciences of Brest (EA4685), University of Western Brittany, Brest, France.,Dental School, University of Western Brittany, Brest, France
| | - Céline Bodéré
- Laboratory of Neurosciences of Brest (EA4685), University of Western Brittany, Brest, France.,Dental School, University of Western Brittany, Brest, France.,Assessment and Treatment Center of Pain, Regional and University Hospital Center, Brest, France
| | - Cyrielle Hélou
- Dental School, University of Western Brittany, Brest, France
| | - Valérie Chevalier
- Dental School, University of Western Brittany, Brest, France.,Laboratory IRDL, FRE CNRS 3744, University of Western Brittany, Brest, France
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14
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Solé-Magdalena A, Martínez-Alonso M, Coronado CA, Junquera LM, Cobo J, Vega JA. Molecular basis of dental sensitivity: The odontoblasts are multisensory cells and express multifunctional ion channels. Ann Anat 2017; 215:20-29. [PMID: 28954208 DOI: 10.1016/j.aanat.2017.09.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 08/22/2017] [Accepted: 09/10/2017] [Indexed: 12/26/2022]
Abstract
Odontoblasts are the dental pulp cells responsible for the formation of dentin. In addition, accumulating data strongly suggest that they can also function as sensory cells that mediate the early steps of mechanical, thermic, and chemical dental sensitivity. This assumption is based on the expression of different families of ion channels involved in various modalities of sensitivity and the release of putative neurotransmitters in response to odontoblast stimulation which are able to act on pulp sensory nerve fibers. This review updates the current knowledge on the expression of transient-potential receptor ion channels and acid-sensing ion channels in odontoblasts, nerve fibers innervating them and trigeminal sensory neurons, as well as in pulp cells. Moreover, the innervation of the odontoblasts and the interrelationship been odontoblasts and nerve fibers mediated by neurotransmitters was also revisited. These data might provide the basis for novel therapeutic approaches for the treatment of dentin sensibility and/or dental pain.
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Affiliation(s)
- A Solé-Magdalena
- Departamento de Morfología y Biología Celular Universidad de Oviedo, Spain
| | - M Martínez-Alonso
- Departamento de Morfología y Biología Celular Universidad de Oviedo, Spain
| | - C A Coronado
- Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Temuco, Chile
| | - L M Junquera
- Departamento de Especialidades Médico-Quirúrgicas, Universidad de Oviedo, Spain; Servicio de Cirugía Maxilofacial, Hospital Universitario Central de Asturias, Oviedo, Spain
| | - J Cobo
- Departamento de Especialidades Médico-Quirúrgicas, Universidad de Oviedo, Spain; Instituto Asturiano de Odontología, Oviedo, Spain
| | - J A Vega
- Departamento de Morfología y Biología Celular Universidad de Oviedo, Spain; Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Temuco, Chile.
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15
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Rueggeberg FA, Giannini M, Arrais CAG, Price RBT. Light curing in dentistry and clinical implications: a literature review. Braz Oral Res 2017; 31:e61. [PMID: 28902241 DOI: 10.1590/1807-3107bor-2017.vol31.0061] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 05/22/2017] [Indexed: 11/21/2022] Open
Abstract
Contemporary dentistry literally cannot be performed without use of resin-based restorative materials. With the success of bonding resin materials to tooth structures, an even wider scope of clinical applications has arisen for these lines of products. Understanding of the basic events occurring in any dental polymerization mechanism, regardless of the mode of activating the process, will allow clinicians to both better appreciate the tremendous improvements that have been made over the years, and will also provide valuable information on differences among strategies manufacturers use to optimize product performance, as well as factors under the control of the clinician, whereby they can influence the long-term outcome of their restorative procedures.
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Affiliation(s)
- Frederick Allen Rueggeberg
- Augusta University, Dental College of Georgia, Department of Restorative Sciences, Augusta, GA, United States of America
| | - Marcelo Giannini
- Universidade Estadual de Campinas - Unicamp, Piracicaba Dental School, Department of Restorative Dentistry, Piracicaba, SP, Brazil
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16
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Niu L, Dong SJ, Kong TT, Wang R, Zou R, Liu QD. Heat Transfer Behavior across the Dentino-Enamel Junction in the Human Tooth. PLoS One 2016; 11:e0158233. [PMID: 27662186 PMCID: PMC5035055 DOI: 10.1371/journal.pone.0158233] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 08/15/2016] [Indexed: 11/18/2022] Open
Abstract
During eating, the teeth usually endure the sharply temperature changes because of different foods. It is of importance to investigate the heat transfer and heat dissipation behavior of the dentino-enamel junction (DEJ) of human tooth since dentine and enamel have different thermophysical properties. The spatial and temporal temperature distributions on the enamel, dentine, and pulpal chamber of both the human tooth and its discontinuous boundaries, were measured using infrared thermography using a stepped temperature increase on the outer boundary of enamel crowns. The thermal diffusivities for enamel and dentine were deduced from the time dependent temperature change at the enamel and dentine layers. The thermal conductivities for enamel and dentine were calculated to be 0.81 Wm-1K-1 and 0.48 Wm-1K-1 respectively. The observed temperature discontinuities across the interfaces between enamel, dentine and pulp-chamber layers were due to the difference of thermal conductivities at interfaces rather than to the phase transformation. The temperature gradient distributes continuously across the enamel and dentine layers and their junction below a temperature of 42°C, whilst a negative thermal resistance is observed at interfaces above 42°C. These results suggest that the microstructure of the dentin-enamel junction (DEJ) junction play an important role in tooth heat transfer and protects the pulp from heat damage.
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Affiliation(s)
- Lin Niu
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi'an, Shaanxi, China
- Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, College of Stomatology, Xi’an Jiaotong University, Xi'an, Shaanxi, China
- Stomatology Hospital of Xi’an Jiaotong University College of Medicine, Xi'an, Shaanxi, China
| | - Shao-Jie Dong
- Stomatology Hospital of Xi’an Jiaotong University College of Medicine, Xi'an, Shaanxi, China
| | - Ting-Ting Kong
- Stomatology Hospital of Xi’an Jiaotong University College of Medicine, Xi'an, Shaanxi, China
| | - Rong Wang
- State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Rui Zou
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi'an, Shaanxi, China
- Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, College of Stomatology, Xi’an Jiaotong University, Xi'an, Shaanxi, China
- Stomatology Hospital of Xi’an Jiaotong University College of Medicine, Xi'an, Shaanxi, China
- * E-mail: (RZ); (QDL)
| | - Qi-Da Liu
- State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- * E-mail: (RZ); (QDL)
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17
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Velázquez-López J, Cruz-Gómez MA, Ruelas-Oronia MA, Dipp-Velázquez F, Dib-Kanan A, Méndez-Mancilla Z. Analysis and simulation of heat transfer in human tooth during the curing of orthodontic appliance and food ingestion. APOS TRENDS IN ORTHODONTICS 2016. [DOI: 10.4103/2321-1407.183153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The aim of this study was to analyze and simulate the heat transfer in the human tooth undergoing fixed orthodontic appliances and food intake. An in vivo representative mathematic model of a layered thermographic profile was developed during the LED curing of Gemini bracket 0.022 in slot (conventional ligating system) and Transbond XT adhesive. The characterization of the layered thermic response allowed to identify if during the LED curing process, according to manufacturer’s specification (light curing unit, adhesive) can induce pulpar necrosis. The profile’s thermographic model was the simulation basis of many conditions such as food intake, due to in vivo metrology is affected by the impossibility of a correct apparatus position and the physiologic function of the oral cavity which is exposed to uncontrollable temperature changes. The metrology was carried out with a T-440 thermographic camera during LED curing bracket, using a LED curing light (Elipar S10) placed at 3 ± 1 mm for 5 s at each mesial and distal surface. The thermography outcomes were analyzed in the FLIR Tools Software, Microsoft Excel 2013 and SPSS 22. To adjust the mathematic model error, in vitro studies were performed on third molars for the purpose of realizing extreme exposition temperature condition tests caused by the LED curing unit without jeopardizing the human tooth vitality as would it be on in vivo experimentation. The bracket curing results according to manufacturer’s conditions reached 39°C in vivo temperatures and 47°C on in vitro tests, which does not jeopardize human tooth vitality as said by previous researches, although, an LED curing precise protocol established by the manufacturer’s LED curing light is sustained.
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Affiliation(s)
- J. Velázquez-López
- Autonomous University of Puebla, Faculty of Stomatology, Stomatology Master of Science in Orthodontics, Graduate Building, Orthodontics Clinic, Puebla, México,
| | - M. A. Cruz-Gómez
- Faculty of Engineering, I.M.E. School, Tribology and Transport Group, Graduate Building, First Floor, Cubicle Num. 16, Valsequillo Blvd., San Claudio Ave., University City, San Manuel Colony, Puebla, México
| | - M. A. Ruelas-Oronia
- Autonomous University of Puebla, Faculty of Stomatology, Stomatology Master of Science in Orthodontics, Graduate Building, Orthodontics Clinic, Puebla, México,
| | - F. Dipp-Velázquez
- Autonomous University of Puebla, Faculty of Stomatology, Stomatology Master of Science in Orthodontics, Graduate Building, Orthodontics Clinic, Puebla, México,
| | - A. Dib-Kanan
- Autonomous University of Puebla, Faculty of Stomatology, Stomatology Master of Science in Orthodontics, Graduate Building, Orthodontics Clinic, Puebla, México,
| | - Z. Méndez-Mancilla
- Autonomous University of Puebla, Faculty of Stomatology, Stomatology Master of Science in Orthodontics, Graduate Building, Orthodontics Clinic, Puebla, México,
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18
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LED Curing Lights and Temperature Changes in Different Tooth Sites. BIOMED RESEARCH INTERNATIONAL 2016; 2016:1894672. [PMID: 27195282 PMCID: PMC4852368 DOI: 10.1155/2016/1894672] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 03/08/2016] [Accepted: 03/28/2016] [Indexed: 11/21/2022]
Abstract
Objectives. The aim of this in vitro study was to assess thermal changes on tooth tissues during light exposure using two different LED curing units. The hypothesis was that no temperature increase could be detected within the dental pulp during polymerization irrespective of the use of a composite resin or a light-curing unit. Methods. Caries-free human first molars were selected, pulp residues were removed after root resection, and four calibrated type-J thermocouples were positioned. Two LED lamps were tested; temperature measurements were made on intact teeth and on the same tooth during curing of composite restorations. The data was analyzed by one-way analysis of variance (ANOVA), Wilcoxon test, Kruskal-Wallis test, and Pearson's χ2. After ANOVA, the Bonferroni multiple comparison test was performed. Results. Polymerization data analysis showed that in the pulp chamber temperature increase was higher than that without resin. Starlight PRO, in the same condition of Valo lamp, showed a lower temperature increase in pre- and intrapolymerization. A control group (without composite resin) was evaluated. Significance. Temperature increase during resin curing is a function of the rate of polymerization, due to the exothermic polymerization reaction, the energy from the light unit, and time of exposure.
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19
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Runnacles P, Arrais CAG, Pochapski MT, dos Santos FA, Coelho U, Gomes JC, De Goes MF, Gomes OMM, Rueggeberg FA. In vivo temperature rise in anesthetized human pulp during exposure to a polywave LED light curing unit. Dent Mater 2015; 31:505-13. [DOI: 10.1016/j.dental.2015.02.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 01/08/2015] [Accepted: 02/02/2015] [Indexed: 11/26/2022]
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20
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Talebi M, Moghimi S, Shafagh M, Kalani H, Mazhari F. In vitro investigation of heat transfer phenomenon in human immature teeth. J Dent Res Dent Clin Dent Prospects 2015; 8:218-24. [PMID: 25587383 PMCID: PMC4288911 DOI: 10.5681/joddd.2014.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 01/18/2014] [Indexed: 11/17/2022] Open
Abstract
Background and aims. Heat generated within tooth during clinical dentistry can cause thermally induced damage to hard and soft components of the tooth (enamel, dentin and pulp). Geometrical characteristics of immature teeth are different from those of mature teeth. The purpose of this experimental and theoretical study was to investigate thermal changes in immature permanent teeth during the use of LED light-curing units (LCU). Materials and methods. This study was performed on the second mandibular premolars. This experimental investiga-tion was carried out for recording temperature variations of different sites of tooth and two dimensional finite element models were used for heat transfer phenomenon in immature teeth. Sensitivity analysis and local tests were included in the model validation phase. Results. Overall, thermal stimulation for 30 seconds with a low-intensity LED LCU increased the temperature from 28°C to 38°C in IIT (intact immature tooth) and PIT (cavity-prepared immature tooth). When a high-intensity LED LCU was used, tooth temperature increased from 28°C to 48°C. The results of the experimental tests and mathematical modeling illustrated that using LED LCU on immature teeth did not have any detrimental effect on the pulp temperature. Conclusion. Using LED LCU in immature teeth had no effect on pulp temperature in this study. Sensitivity analysis showed that variations of heat conductivity might affect heat transfer in immature teeth; therefore, further studies are required to determine thermal conductivity of immature teeth.
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Affiliation(s)
- Maryam Talebi
- Associate Professor, Dental Materials Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Sahar Moghimi
- Assistant Professor, Department of Electrical Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Mina Shafagh
- MD, Department of Pediatric Dentistry, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hadi Kalani
- PhD Candidate, Department of Mechanical Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Fatemeh Mazhari
- Associate Professor, Dental Materials Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
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21
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Bleicher F. Odontoblast physiology. Exp Cell Res 2014; 325:65-71. [DOI: 10.1016/j.yexcr.2013.12.012] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 12/03/2013] [Accepted: 12/08/2013] [Indexed: 11/25/2022]
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22
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Lin M, Genin GM, Xu F, Lu T. Thermal Pain in Teeth: Electrophysiology Governed by Thermomechanics. APPLIED MECHANICS REVIEWS 2014; 66:0308011-3080114. [PMID: 25516631 PMCID: PMC4240033 DOI: 10.1115/1.4026912] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 02/01/2014] [Indexed: 05/12/2023]
Abstract
Thermal pain arising from the teeth is unlike that arising from anywhere else in the body. The source of this peculiarity is a long-standing mystery that has begun to unravel with recent experimental measurements and, somewhat surprisingly, new thermomechanical models. Pain from excessive heating and cooling is typically sensed throughout the body through the action of specific, heat sensitive ion channels that reside on sensory neurons known as nociceptors. These ion channels are found on tooth nociceptors, but only in teeth does the pain of heating differ starkly from the pain of cooling, with cold stimuli producing more rapid and sharper pain. Here, we review the range of hypotheses and models for these phenomena, and focus on what is emerging as the most promising hypothesis: pain transduced by fluid flowing through the hierarchical structure of teeth. We summarize experimental evidence, and critically review the range of heat transfer, solid mechanics, fluid dynamics, and electrophysiological models that have been combined to support this hypothesis. While the results reviewed here are specific to teeth, this class of coupled thermomechanical and neurophysiological models has potential for informing design of a broad range of thermal therapies and understanding of a range of biophysical phenomena.
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Affiliation(s)
- Min Lin
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University , Xi'an 710049 , China
| | - Guy M Genin
- Department of Neurological Surgery, and School of Engineering, Washington University , St. Louis, MO 63110
| | - Feng Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University , Xi'an 710049 , China
| | - TianJian Lu
- Bioinspired Engineering and Biomechanics Center, Xi'an Jiaotong University , Xi'an 710049 , China e-mail:
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23
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Tsumura M, Sobhan U, Sato M, Shimada M, Nishiyama A, Kawaguchi A, Soya M, Kuroda H, Tazaki M, Shibukawa Y. Functional expression of TRPM8 and TRPA1 channels in rat odontoblasts. PLoS One 2013; 8:e82233. [PMID: 24358160 PMCID: PMC3864925 DOI: 10.1371/journal.pone.0082233] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 10/22/2013] [Indexed: 11/18/2022] Open
Abstract
Odontoblasts produce dentin during development, throughout life, and in response to pathological conditions by sensing stimulation of exposed dentin. The functional properties and localization patterns of transient receptor potential (TRP) melastatin subfamily member 8 (TRPM8) and ankyrin subfamily member 1 (TRPA1) channels in odontoblasts remain to be clarified. We investigated the localization and the pharmacological, biophysical, and mechano-sensitive properties of TRPM8 and TRPA1 channels in rat odontoblasts. Menthol and icilin increased the intracellular free Ca(2+) concentration ([Ca(2+)]i). Icilin-, WS3-, or WS12-induced [Ca(2+)]i increases were inhibited by capsazepine or 5-benzyloxytriptamine. The increase in [Ca(2+)]i elicited by allyl isothiocyanate (AITC) was inhibited by HC030031. WS12 and AITC exerted a desensitizing effect on [Ca(2+)]i increase. Low-temperature stimuli elicited [Ca(2+)]i increases that are sensitive to both 5-benzyloxytriptamine and HC030031. Hypotonic stimulation-induced membrane stretch increased [Ca(2+)]i; HC030031 but not 5-benzyloxytriptamine inhibited the effect. The results suggest that TRPM8 channels in rat odontoblasts play a role in detecting low-temperature stimulation of the dentin surface and that TRPA1 channels are involved in sensing membrane stretching and low-temperature stimulation. The results also indicate that odontoblasts act as mechanical and thermal receptor cells, detecting the stimulation of exposed dentin to drive multiple cellular functions, such as sensory transduction.
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Affiliation(s)
- Maki Tsumura
- Department of Physiology, Tokyo Dental College, Chiba, Japan
| | - Ubaidus Sobhan
- Department of Physiology, Tokyo Dental College, Chiba, Japan
- Clinical Research Center, National Center for Child Health and Development, Tokyo, Japan
| | - Masaki Sato
- Department of Physiology, Tokyo Dental College, Chiba, Japan
| | - Miyuki Shimada
- Department of Clinical Oral Health Science, Tokyo Dental College, Tokyo, Japan
| | - Akihiro Nishiyama
- Department of Oral Medicine, Oral and Maxillofacial Surgery, Tokyo Dental College, Chiba, Japan
| | - Aya Kawaguchi
- Department of Dental Anesthesiology, Tokyo Dental College, Chiba, Japan
| | - Manabu Soya
- Department of Dental Anesthesiology, Tokyo Dental College, Chiba, Japan
| | - Hidetaka Kuroda
- Department of Anesthesiology and Pain Relief Center, University of Tokyo Hospital, Tokyo, Japan
| | - Masakazu Tazaki
- Department of Physiology, Tokyo Dental College, Chiba, Japan
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24
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Su KC, Chuang SF, Ng EYK, Chang CH. An investigation of dentinal fluid flow in dental pulp during food mastication: simulation of fluid-structure interaction. Biomech Model Mechanobiol 2013; 13:527-35. [PMID: 23913183 DOI: 10.1007/s10237-013-0514-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Accepted: 07/10/2013] [Indexed: 11/28/2022]
Abstract
This study uses fluid-structure interaction (FSI) simulation to investigate the relationship between the dentinal fluid flow in the dental pulp of a tooth and the elastic modulus of masticated food particles and to investigate the effects of chewing rate on fluid flow in the dental pulp. Three-dimensional simulation models of a premolar tooth (enamel, dentine, pulp, periodontal ligament, cortical bone, and cancellous bone) and food particle were created. Food particles with elastic modulus of 2,000 and 10,000 MPa were used, respectively. The external displacement loading (5 μm) was gradually directed to the food particle surface for 1 and 0.1 s, respectively, to simulate the chewing of food particles. The displacement and stress on tooth structure and fluid flow in the dental pulp were selected as evaluation indices. The results show that masticating food with a high elastic modulus results in high stress and deformation in the tooth structure, causing faster dentinal fluid flow in the pulp in comparison with that obtained with soft food. In addition, fast chewing of hard food particles can induce faster fluid flow in the pulp, which may result in dental pain. FSI analysis is shown to be a useful tool for investigating dental biomechanics during food mastication. FSI simulation can be used to predict intrapulpal fluid flow in dental pulp; this information may provide the clinician with important concept in dental biomechanics during food mastication.
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Affiliation(s)
- Kuo-Chih Su
- Department of Biomedical Engineering College of Engineering, National Cheng Kung University, 1 University Road, Tainan City, 701, Taiwan
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25
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Su KC, Chang CH, Chuang SF, Ng EYK. The effect of dentinal fluid flow during loading in various directions—Simulation of fluid–structure interaction. Arch Oral Biol 2013; 58:575-82. [DOI: 10.1016/j.archoralbio.2012.10.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2012] [Revised: 09/26/2012] [Accepted: 10/01/2012] [Indexed: 11/26/2022]
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26
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Oskui IZ, Ashtiani MN, Hashemi A, Jafarzadeh H. Thermal analysis of the intact mandibular premolar: a finite element analysis. Int Endod J 2013; 46:841-6. [DOI: 10.1111/iej.12069] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 11/15/2012] [Indexed: 11/30/2022]
Affiliation(s)
- I. Z. Oskui
- Faculty of Biomedical Engineering; Amirkabir University of Technology; Tehran; Iran
| | - M. N. Ashtiani
- Laboratory of Biomechanical Researches, Department of Mechanical Engineering; Sahand University of Technology; Tabriz
| | - A. Hashemi
- Faculty of Biomedical Engineering; Amirkabir University of Technology; Tehran; Iran
| | - H. Jafarzadeh
- Dental Research Center; Department of Endodontics; Faculty of Dentistry; Mashhad University of Medical Sciences; Mashhad; Iran
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Effect of Er,Cr:YSGG laser on human dentin fluid flow. Lasers Med Sci 2012; 28:1445-51. [PMID: 23073836 DOI: 10.1007/s10103-012-1218-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 10/01/2012] [Indexed: 10/27/2022]
Abstract
The aim of the current investigation was to assess the rate and magnitude of dentin fluid flow of dentinal surfaces irradiated with Er,Cr:YSGG laser. Twenty extracted third molars were sectioned, mounted, and irradiated with Er,Cr:YSGG laser at 3.5 and 4.5 W power settings. Specimens were connected to an automated fluid flow measurement apparatus (Flodec). The rate, magnitude, and direction of dentin fluid flow were recorded at baseline and after irradiation. Nonparametric Wilcoxon signed ranks repeated measure t test revealed a statistically significant reduction in fluid flow for all the power settings. The 4.5-W power output reduced the flow significantly more than the 3.5 W. The samples showed a baseline outward flow followed by inward flow due to irradiation then followed by decreased outward flow. It was concluded that Er,Cr:YSGG laser irradiation at 3.5 and 4.5 W significantly reduced dentinal fluid flow rate. The reduction was directly proportional to power output.
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ZHU YJ, XU F, SU JH, ZHOU H, LU TJ. MATHEMATICAL MODELING FOR THE PREDICTION AND IMPROVEMENT OF TOOTH THERMAL PAIN: A REVIEW. J MECH MED BIOL 2012. [DOI: 10.1142/s0219519411004095] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Tooth pain, especially tooth thermal pain, is one of the most important symptoms and signs in dental clinic and daily life. As a special sensation, pain has been studied extensively in both clinic and experimental research aimed at reducing or eliminating the possible negative effects of pain. Unfortunately, the full underlying mechanism of pain is still unclear, because the pain could be influenced by many factors, including physiological, psychological, physical, chemical, and biological factors and so on. Besides, most studies on pain mechanisms in the literature are based on skin pain sensation and only few are based on tooth pain. In this paper, we present a comprehensive review on both neurophysiology of tooth pain mechanism, and corresponding thermal, mechanical, and thermomechanical behaviors of teeth. We also describe a multiscale modeling approach for quantifying tooth thermal pain by integrating the mathematic methods of engineering into the neuroscience. The mathematical model of tooth thermal pain will enable better understanding of thermal pain mechanism and optimization of existing diagnosis and treatment in dental clinic.
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Affiliation(s)
- Y. J. ZHU
- Stomatological Hospital, College of Medicine, Biomedical Engineering and Biomechanics Center, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - F. XU
- Biomedical Engineering and Biomechanics Center, Xi'an Jiaotong University, Xi'an 710049, P. R. China
- School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - J. H. SU
- Biomedical Engineering and Biomechanics Center, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - H. ZHOU
- Stomatological Hospital, College of Medicine, Xi'an Jiaotong University, Xi'an 710004, P. R. China
| | - T. J. LU
- Biomedical Engineering and Biomechanics Center, Xi'an Jiaotong University, Xi'an 710049, P. R. China
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LIN M, LUO ZY, BAI BF, XU F, LU TJ. FLUID DYNAMICS ANALYSIS OF SHEAR STRESS ON NERVE ENDINGS IN DENTINAL MICROTUBULE: A QUANTITATIVE INTERPRETATION OF HYDRODYNAMIC THEORY FOR DENTAL PAIN. J MECH MED BIOL 2011. [DOI: 10.1142/s0219519411003983] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Noxious thermal and/or mechanical stimuli applied to dentine can cause fluid flow in dentinal microtubules (DMTs). The fluid flow induces shear stress (SS) on intradental nerve endings and may excite pulpal mechanoreceptors to generate dental pain sensation. There exist numerous studies on dental thermal pain, but few are mathematical. For this, we developed a computational fluid dynamics (CFD) model of dentinal fluid flow (DFF) in innervated DMTs. Based on this model, we systematically investigated the effects of various parameters (e.g., biological structure, DFF velocity, and fluid properties) on the SS experienced by intradental nerve endings and thus provide a quantitative interpretation to the hydrodynamic theory. The dimensions of biological structures, odontoblastic process (OP) movement, dentinal fluid velocity, and viscosity were found to have significant influences on the SS while dentinal fluid density showed negligible influence under conditions studied. The results indicate that: (i) dental pain study of animal models may not be directly applied to human being and the results may even vary from one person to another and (ii) OP movement caused by DFF changes the dimension of the space for the fluid flow, affecting thus the SS on nerve endings. The present work enables better understanding of the mechanisms underlying dental pain sensation and quantification of dental pain intensity resulted from clinical procedures such as dentine sensitivity testing and dental restorative processes.
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Affiliation(s)
- M. LIN
- Biomedical Engineering and Biomechanics Center, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Z. Y. LUO
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University Xi'an 710049, P. R. China
| | - B. F. BAI
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University Xi'an 710049, P. R. China
| | - F. XU
- Biomedical Engineering and Biomechanics Center, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, P. R. China
- HST-Center for Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - T. J. LU
- Biomedical Engineering and Biomechanics Center, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, P. R. China
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Fluid mechanics in dentinal microtubules provides mechanistic insights into the difference between hot and cold dental pain. PLoS One 2011; 6:e18068. [PMID: 21448459 PMCID: PMC3063177 DOI: 10.1371/journal.pone.0018068] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 02/19/2011] [Indexed: 11/19/2022] Open
Abstract
Dental thermal pain is a significant health problem in daily life and dentistry. There is a long-standing question regarding the phenomenon that cold stimulation evokes sharper and more shooting pain sensations than hot stimulation. This phenomenon, however, outlives the well-known hydrodynamic theory used to explain dental thermal pain mechanism. Here, we present a mathematical model based on the hypothesis that hot or cold stimulation-induced different directions of dentinal fluid flow and the corresponding odontoblast movements in dentinal microtubules contribute to different dental pain responses. We coupled a computational fluid dynamics model, describing the fluid mechanics in dentinal microtubules, with a modified Hodgkin-Huxley model, describing the discharge behavior of intradental neuron. The simulated results agreed well with existing experimental measurements. We thence demonstrated theoretically that intradental mechano-sensitive nociceptors are not “equally sensitive” to inward (into the pulp) and outward (away from the pulp) fluid flows, providing mechanistic insights into the difference between hot and cold dental pain. The model developed here could enable better diagnosis in endodontics which requires an understanding of pulpal histology, neurology and physiology, as well as their dynamic response to the thermal stimulation used in dental practices.
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Analysis of thermal-induced dentinal fluid flow and its implications in dental thermal pain. Arch Oral Biol 2011; 56:846-54. [PMID: 21411060 DOI: 10.1016/j.archoralbio.2011.02.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 01/27/2011] [Accepted: 02/11/2011] [Indexed: 11/21/2022]
Abstract
OBJECTIVES The initiation of the pain sensation experienced following the thermal stimulation of dentine has been correlated with fluid flow in the dentinal tubules. There may be other mechanisms. METHODS This study examines this possibility using a mathematical model to simulate the temperature and thermal stress distribution in a tooth undergoing thermal stimulation. The results obtained were then used to predict the fluid flow in a single dentinal tubule by considering the deformation of the dentinal tubules and dentinal fluid. RESULTS Deformation of the pulp chamber was observed before a noticeable temperature change was recorded at the dentine-enamel junction. Tubule deformation leads to changes in fluid flow more rapidly than fluid expansion or contraction. This finding agreed with previously reported experimental observations. An initially high rate of outward fluid flow under cooling was found to correspond to short latency neural responses whilst heating was associated with long latency neural responses. CONCLUSION Rapid fluid flow caused by thermal deformation of dentinal tubules may account for the short latency (<1s) activation of mechano-sensitive receptors after of cooling. Long latency (>10s) neural responses could be associated with the activation of thermo-sensitive receptors.
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Jafarzadeh H, Abbott PV. Review of pulp sensibility tests. Part I: general information and thermal tests. Int Endod J 2010; 43:738-62. [DOI: 10.1111/j.1365-2591.2010.01754.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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33
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A review of heat transfer in human tooth—Experimental characterization and mathematical modeling. Dent Mater 2010; 26:501-13. [DOI: 10.1016/j.dental.2010.02.009] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 01/04/2010] [Accepted: 02/23/2010] [Indexed: 12/28/2022]
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Linsuwanont P, Versluis A, Palamara JE, Messer HH. Thermal stimulation causes tooth deformation: a possible alternative to the hydrodynamic theory? Arch Oral Biol 2007; 53:261-72. [PMID: 18037388 DOI: 10.1016/j.archoralbio.2007.10.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Revised: 08/13/2007] [Accepted: 10/06/2007] [Indexed: 10/22/2022]
Abstract
OBJECTIVES To investigate the relationship between temperature distribution and tooth structure deformation during and after localised application of thermal stimuli used during pulp vitality testing. METHODS Strains and temperature changes within tooth structures were recorded when three different thermal stimuli, namely heated gutta percha (120-140 degrees C), carbon dioxide dry ice (-72 degrees C) and refrigerant spray (-50 degrees C), were applied to extracted bovine incisors. Each stimulus was applied for 5s on the labial enamel surface in a random order, with a 30-min interval between tests. Finite element analysis was performed on basic geometrical shapes to investigate structural deformation in relation to temperature change. RESULTS Application of thermal stimuli to the labial enamel surface resulted in rapid development of strain at the pulpal dentine surface before any temperature change was detected at the dentino-enamel junction. The strain pattern was biphasic; heat produced an initial contraction of the pulpal surface, followed by an expansion, and the reverse pattern was found with cold stimulation. Finite element analysis confirmed that the initially pronounced thermal gradient across the enamel and dentine caused rapid flexural deformation before temperature changes reached the dentino-enamel junction. When the temperature changes reached the pulpal dentine and thus reduced the thermal gradient, the direction of the strain was reversed. CONCLUSION These results indicate possible alternatives to the hydrodynamic theory for thermal stimuli applied to intact teeth. Mechanically induced dentine deformation may trigger nerve impulses directly, or may exert mechanically induced dentinal fluid flow that triggers nerve activity.
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Affiliation(s)
- Pairoj Linsuwanont
- School of Dental Science, University of Melbourne, Melbourne, Victoria, Australia
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