Tf the hydrodynamic theory states that a stimulus at the outer aspect of dentin causes fluid movement within the dentinal tubules. But how it reaches the nerve endings could not be explained. Quick response code dentine hypersensitivity an enigma. There are three main theories of dentine hypersensitivity. Now let us get to know about each of these theories briefly. However, understanding such a receptor and its associated mechanism of action only began not long ago. Aadr symposium 162 revisiting the hydrodynamic theory in the age of molecular pain organizerschairs. The literary standard and academic tone are as jarring as its emphatically repeated message to reject the bulk of quantum theory, general relativity, the standard particle. A hydrodynamic mechanism in the transmission of pain producing stimuli through the dentine. Chapter 6 an introduction to hydrodynamic stability. It is unique in that it resides in a rigid chamber which provides strong mechanical support and protection from the. Gardners hydrodynamic theory of syringomyelia revisited.
Cracked tooth exposed dentin caries 18 jk mitchell, dds, med. Caries exposes tubules, which can be sensitive to air or sweets. The movement of fluid can be toward the inside of the pulp or the outside of dentin. Pain associated with tooth sensitivity typically is very abrupt. Ken wheeler the missing secrets of magnetism theoria. Nomenclature roman letters a pipe radius a crosssectional area a ijk coe. According to this theory the stimuli reaches the nerve endings in the inner dentin. Renton, kings college london dental institute, london, uk 8. The most widely accepted theory of how the pain occurs is brannstrom.
Developed by brannstrom in 1960, the hydrodynamic theory is the currently accepted explanation for transmission of stimuli from the outer surface of dentin and pulp. The role of transient receptor potential trp channels in. This process is similar to activating the neural fibers around the hair by touching or pressing the hair. Dentinal hypersensitivity14 is a long known pain and is frequently encountered disease in clinical practice.
When a load is applied to a tooth, movement of dentinal fluid will occur within the dentinal tubules 24, which may activate nociceptors and mechanical receptors in the pulp and cause pain 25,26. Some reports indicate it occurs in 15% to 20% of all dental patients. A specific definition of dentinal hypersensitivity is given below, after which the mechanism of hypersensitivity is described in terms of hydrodynamic theory. Sensation in preparations, caries, and the dentinal crack. Described the hydrodynamic theory of pain yogi bera, okeson observe and listen to history for dx okeson 1995 referred pain, often in a vertical pattern arch to arch consider selective anesthesia as additional dx tool if local anesthesia at the site of pain fails to reduce pain consider referred pain eriksen 1991 11 years follow up. Once initiated, it can either remain as sensitivity or it can trigger pain and creates severe discomfort for the patient. As soon as the cause of the sensitivity is removed, the pain has a. The hydrodynamic or fluid movement theory is one of the main theories in dentistry to explain the mechanism by which a tooth perceives the sensation of pain. The process is called the hydrodynamic theory of pain 3, 14. This body can be translating and possibly rotating, but not deforming. The movement of fluid stimulates a baroreceptor and leads to neural discharge.
Risk factors are numerous often acting synergistically and always influenced by individual. Transduction theory membrane of the odontoblast process is excited by the stimulus and the impulse is conduct to the. Patientcentered dentinal hypersensitivity treatment. Cold stimuli cause an outward flow of fluid and hot stimuli cause an inward flow. Changes in sensory thresholds of the pulp and periodontal. The hydrodynamic theory of dentinal pain journal of endodontics. Find materials for this course in the pages linked along the left. Sensation in preparations, caries, and the dentinal crack syndrome. A hydrodynamic mechanism in the transmission of pain producing. The initiation and progression of dhs are influenced by characteristics. Hydrodynamic theory definition of hydrodynamic theory by.
This theory proposes that syringomyelia results from a. Introduction to basic principles of fluid mechanics. The flow of liquids in dentinal tubules can trigger nerves along the pulpal canal of the dentin, causing pain. Before the discovery of local anesthetics, dentists would use toxic chemicals such as silver nitrate, zinc chloride, potash. The implications of this book have been reverberating rather uncomfortably in my mind for days. According to brannstroms hydrodynamic theory 8, when an appropriate stimulus is applied to the outer dentin surface, there is a displacement of the contents of the dentinal tubules that gives rise to a mechanical stimulation of the neurons at the pulpodentinal border. This process is similar to activating the neural fibers around the hair by touching or pressing the. It is currently the most widely accepted theory used to explain tooth sensitivity.
The sensation a person feels in his or her tooth, based on the hydrodynamic theory, usually occurs only when a stimulus such as a blast of air is present. Accordingly, the number and the diameter of the dentine tubules are considered important factors in initiating pain from dhs 26,27. The dental professional, using a variety of diagnostic techniques, will discern the condition from other conditions that may cause sensitive teeth. The pain response varies substantially from one person to another. The initiation and progression of dhs are influenced by characteristics of the teeth and periodontium as well as the oral environment and external influences. The pain may be increased by heat and relieved by cold, although in some cases continued application of. But smaller c fibres tend to be maintained hence high intensity gates remain open causing pain 17. Lowthreshold mechanosensors as pain neurons in the tooth. Hence, the higher the number and greater the diameter of the open dentine tubules the more intense will be the pain from dhs.
Introduction to basic principles of fluid mechanics i. Chief among them is gardners hydrodynamic theory, widely accepted for more than two decades. The hydrodynamic theory assumes that the pain sensation from teeth is attributed. The role of fluoride in the preventive management of. The hydrodynamic theory seems to provide the most feasible explanation of the events that occur. The condition generally involves the facial surfaces of teeth near the cervical aspect and is very common in premolars and canines. Conclusions the current pain mechanism of dhs is thought to be the hydrodynamic theory. Gardner attributed the genesis of syringomyelia to craniospinal pressure differentials in the setting of fourth ventricular outlet.
Abstractseveral theories have been put forth to explain the pathogenesis of syringomyelia, the formation of longitudinal, fluidfilled cavities within the spinal cord. Dentin exposure, usually at the cervical margin, is due to a variety of processes involving gingival recession or loss of enamel, predisposing factors being periodontal disease and treatment, limited alveolar bone, thin biotype, erosion and abrasion. Number of theories have been put forward to explain the mechanism of hypersensitivity causing pain but hydrodynamic theory is most widely accepted nowadays. In rigid body mechanics the motion of a body is described in terms of the bodys position in time. We present theory for ion and water transport through reverse osmosis membranes based on a maxwellstefan framework combined with hydrodynamic theory for the reduced motion of particles in thin pores. Cold as a diagnostic aid in cases of irreversible pulpitis. The current pain mechanism of dhs is thought to be the hydrodynamic theory. The hydrodynamic theory suggests that dentinal pain associ ated with stimulation of a sensitive tooth ultimately involves. In order to exhibit a response to the stimuli, the tubules would have to be. The pain has a rapid onset and is usually of short duration, but it can persist as a dull ache. Brannstroms hydrodynamic theory of pain is globally accepted for the mechanism of dentin. However, dh frequently occurs in the absence of inflamed dentin, so inflammation is not likely the culprit. The phenomenon was first described in the early twentieth century by gysi 1 and was later studied and explained more in detail by brannstrom et al. The hydrodynamic theory is most widely accepted as an explanation of dentine hypersensitivity.
Hydrodynamic theory an overview sciencedirect topics. This dental microstructure has favored the hydrodynamic theory for explaining tooth pain sensation under thermal stimulation, although several other theories have also been proposed e. Effectiveness and safety of tisuacryl in treating dentin. The most widely accepted theory of how the pain occurs is brannstroms hydrodynamic theory, fluid movement within the dentinal tubules. The dental pulp is a unique tissue and its importance in the longterm prognosis of the tooth is often ignored by clinicians. The effect of temperature variations and pressure by using the glass capillary technique, it was easy to demonstrate that application of cold to the tooth pro hydrodynamic theory of dentinal pain 455 duced a rapid outward flow of fluid in the dentinal tubules. Chapter 6 an introduction to hydrodynamic stability anubhab roy and rama govindarajan abstract in this chapter, our objective is twofold. What is gardners hydrodynamic theory of the pathophysiology of syringomyelia. Based on the hydrodynamic theory, dentinal hypersensitivity is a transient tooth pain.