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Tooth Ankylosis
Tooth ankylosis is the pathological fusion between alveolar bone and the cementum of teeth, which is a rare phenomenon in the deciduous dentition and even more uncommon in permanent teeth. Ankylosis occurs when partial root resorption is followed by repair with either cementum or dentine that unites the tooth root with the alveolar bone, usually after trauma. However, root resorption does not necessarily lead to tooth ankylosis and the causes of tooth ankylosis remain uncertain to a large extent. However, it is evident that the incident rate of ankylosis in deciduous teeth is much higher than that of permanent teeth. Risk factors of tooth ankylosis can be generally classified into genetic factors and dental trauma. Diagnostic methods of tooth ankylosis include the use of clinical examinations, x-ray and cone beam computerized tomography (CBCT). Tooth ankylosis could have several symptoms, with decreased tooth count being the most prominent one. Factors like gender and sex may also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dentistry
Dentistry, also known as dental medicine and oral medicine, is the branch of medicine focused on the teeth, gums, and mouth. It consists of the study, diagnosis, prevention, management, and treatment of diseases, disorders, and conditions of the mouth, most commonly focused on dentition (the development and arrangement of teeth) as well as the oral mucosa. Dentistry may also encompass other aspects of the craniofacial complex including the temporomandibular joint. The practitioner is called a dentist. The history of dentistry is almost as ancient as the history of humanity and civilization with the earliest evidence dating from 7000 BC to 5500 BC. Dentistry is thought to have been the first specialization in medicine which have gone on to develop its own accredited degree with its own specializations. Dentistry is often also understood to subsume the now largely defunct medical specialty of stomatology (the study of the mouth and its disorders and diseases) for which reas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tooth Eruption
Tooth eruption is a process in tooth development in which the teeth enter the mouth and become visible. It is currently believed that the periodontal ligament plays an important role in tooth eruption. The first human teeth to appear, the deciduous (primary) teeth (also known as baby or milk teeth), erupt into the mouth from around 6 months until 2 years of age, in a process known as "teething". These teeth are the only ones in the mouth until a person is about 6 years old creating the primary dentition stage. At that time, the first permanent tooth erupts and begins a time in which there is a combination of primary and permanent teeth, known as the mixed dentition stage, which lasts until the last primary tooth is lost. Then, the remaining permanent teeth erupt into the mouth during the permanent dentition stage. Theories Although researchers agree that tooth eruption is a complex process, there is little agreement on the identity of the mechanism that controls eruption. There ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occlusion (dentistry)
Occlusion, in a dental context, means simply the contact between teeth. More technically, it is the relationship between the maxillary (upper) and mandibular (lower) teeth when they approach each other, as occurs during chewing or at rest. Static occlusion refers to contact between teeth when the jaw is closed and stationary, while dynamic occlusion refers to occlusal contacts made when the jaw is moving. The masticatory system also involves the periodontium, the TMJ (and other skeletal components) and the neuromusculature, therefore the tooth contacts should not be looked at in isolation, but in relation to the overall masticatory system. Anatomy of Masticatory System One cannot fully understand occlusion without an in depth understanding of the anatomy including that of the teeth, TMJ, musculature surrounding this and the skeletal components. The Dentition and Surrounding Structures The human dentition consists of 32 permanent teeth and these are distributed between the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Failure Of Eruption Of Teeth
Failure of eruption of teeth happens when a single or multiple teeth fail to erupt in the mouth. This can happen due to many reasons which may include obstruction from primary teeth, bone surrounding the unerupted tooth or other mechanical factors. The two types of failure of eruption are primary failure of eruption and mechanical failure of eruption. Primary failure of eruption has been known to be associated with Parathyroid hormone 1 receptor mutation. Primary failure of eruption The term primary failure of eruption was named by William Proffit and Katherine Vig in 1981. This type of failure of eruption has a genetic or familial background precursor as a cause. The prevalence is of PFE is about 0.06% in population. In this type of failure, teeth that are non-ankylosed fail to erupt in the mouth. These teeth do not have a precursor tooth that is blocking their path. These teeth tend to erupt partially but then fail to erupt as the time goes on. Profitt stated that only the post ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Percussion (medicine)
Percussion is a technique of clinical examination. Overview Percussion is a method of tapping on a surface to determine the underlying structures, and is used in clinical examinations to assess the condition of the thorax or abdomen. It is one of the four methods of clinical examination, together with inspection, palpation, auscultation, and inquiry. It is done with the middle finger of one hand tapping on the middle finger of the other hand using a wrist action. The nonstriking finger (known as the pleximeter) is placed firmly on the body over tissue. When percussing boney areas such as the clavicle, the pleximeter can be omitted and the bone is tapped directly such as when percussing an apical cavitary lung lesion typical of tuberculosis. There are two types of percussion: direct, which uses only one or two fingers; and indirect, which uses only the middle/flexor finger. Broadly classifying, there are four types of percussion sounds: resonant, hyper-resonant, stony dull or dul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementoblastoma
Cementoblastoma, or benign cementoblastoma, is a relatively rare benign neoplasm of the cementum of the teeth. It is derived from ectomesenchyme of odontogenic origin. Cementoblastomas represent less than 0.69–8% of all odontogemic tumors. Signs and symptoms Cementoblastoma usually occurs in people under the age of 25, particularly males. It usually involves the permanent mandibular molars or premolars. The involved tooth usually has a vital pulp. It is attached to the tooth root and may cause its resorption, may involve the pulp canal, grows slowly, tends to expand the overlying cortical plates, and, except for the enlargement produced, is usually asymptomatic. This involves the buccal and lingual aspects of the alveolar ridges. But may be associated with diffuse pain and tooth mobility, but the tooth is still vital. Since a cementoblastoma is a benign neoplasm, it grossly forms a mass of cementum-like tissue as an irregular or round mass attached to the roots of a tooth, usua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflammation
Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving immune cells, blood vessels, and molecular mediators. The function of inflammation is to eliminate the initial cause of cell injury, clear out necrotic cells and tissues damaged from the original insult and the inflammatory process, and initiate tissue repair. The five cardinal signs are heat, pain, redness, swelling, and Functio laesa, loss of function (Latin ''calor'', ''dolor'', ''rubor'', ''tumor'', and ''functio laesa''). Inflammation is a generic response, and therefore it is considered as a mechanism of innate immune system, innate immunity, as compared to adaptive immune system, adaptive immunity, which is specific for each pathogen. Too little inflammation could lead to progressive tissue destruction by the harmful stimulus (e.g. b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Periodontal Fiber
The periodontal ligament, commonly abbreviated as the PDL, is a group of specialized connective tissue fibers that essentially attach a tooth to the alveolar bone within which it sits. It inserts into root cementum one side and onto alveolar bone on the other. Structure The PDL consists of principal fibres, loose connective tissue, blast and clast cells, oxytalan fibres and Cell Rest of Malassez. Alveolodental ligament The main principal fiber group is the alveolodental ligament, which consists of five fiber subgroups: alveolar crest, horizontal, oblique, apical, and interradicular on multirooted teeth. Principal fibers other than the alveolodental ligament are the transseptal fibers. All these fibers help the tooth withstand the naturally substantial compressive forces that occur during chewing and remain embedded in the bone. The ends of the principal fibers that are within either cementum or alveolar bone proper are considered Sharpey fibers. * Alveolar crest fibers ('' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Necrosis
Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated digestion of cell components. In contrast, apoptosis is a naturally occurring programmed and targeted cause of cellular death. While apoptosis often provides beneficial effects to the organism, necrosis is almost always detrimental and can be fatal. Cellular death due to necrosis does not follow the apoptotic signal transduction pathway, but rather various receptors are activated and result in the loss of cell membrane integrity and an uncontrolled release of products of cell death into the extracellular space. This initiates in the surrounding tissue an inflammatory response, which attracts leukocytes and nearby phagocytes which eliminate the dead cells by phagocytosis. However, microbial damaging substances released by leukocytes would crea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Trauma
Dental trauma refers to trauma (injury) to the teeth and/or periodontium (gums, periodontal ligament, alveolar bone), and nearby soft tissues such as the lips, tongue, etc. The study of dental trauma is called dental traumatology.''Textbook and Color Atlas of Traumatic Injuries to the Teeth'', Fourth Edition, edited by Andreason J, Andreasen F, and Andersson L, Wiley-Blackwell, Oxford, UK, 2007 Types Dental injuries Dental injuries include: * Enamel infraction * Enamel fracture * Enamel-dentine fracture * Enamel-dentine fracture involving pulp exposure * Root fracture of tooth Periodontal injuries * Concussion (bruising) *Subluxation of the tooth (tooth knocked loose) * Luxation of the tooth (displaced) **Extrusive ** Intrusive **Lateral * Avulsion of the tooth (tooth knocked out) Injuries to supporting bone This injury involves the alveolar bone and may extend beyond the alveolus. There are five different types of alveolar fractures: * Communicated fracture of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Caries
Tooth decay, also known as cavities or caries, is the breakdown of teeth due to acids produced by bacteria. The cavities may be a number of different colors from yellow to black. Symptoms may include pain and difficulty with eating. Complications may include inflammation of the tissue around the tooth, tooth loss and infection or abscess formation. The cause of cavities is acid from bacteria dissolving the hard tissues of the teeth ( enamel, dentin and cementum). The acid is produced by the bacteria when they break down food debris or sugar on the tooth surface. Simple sugars in food are these bacteria's primary energy source and thus a diet high in simple sugar is a risk factor. If mineral breakdown is greater than build up from sources such as saliva, caries results. Risk factors include conditions that result in less saliva such as: diabetes mellitus, Sjögren syndrome and some medications. Medications that decrease saliva production include antihistamines and antide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malocclusion
In orthodontics, a malocclusion is a misalignment or incorrect relation between the teeth of the upper and lower dental arches when they approach each other as the jaws close. The English-language term dates from 1864; Edward Angle (1855-1930), the "father of modern orthodontics", popularised it. The word "malocclusion" derives from ''occlusion'', and refers to the manner in which opposing teeth meet ('' mal-'' + ''occlusion'' = "incorrect closure"). The malocclusion classification is based on the relationship of the mesiobuccal cusp of the maxillary first molar and the buccal groove of the mandibular first molar. If this molar relationship exists, then the teeth can align into normal occlusion. According to Angle, malocclusion is any deviation of the occlusion from the ideal. However, assessment for malocclusion should also take into account aesthetics and the impact on functionality. If these aspects are acceptable to the patient despite meeting the formal definition of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
