Abfraction

Last updated
Clinical presentation of abfraction non-carious tooth tissue lesions on the cervical margins of upper left canine and premolar Abfraction.jpg
Clinical presentation of abfraction non-carious tooth tissue lesions on the cervical margins of upper left canine and premolar

Abfraction is a theoretical concept explaining a loss of tooth structure not caused by tooth decay (non-carious cervical lesions). It is suggested that these lesions are caused by forces placed on the teeth during biting, eating, chewing and grinding; the enamel, especially at the cementoenamel junction (CEJ), undergoes large amounts of stress, causing micro fractures and tooth tissue loss. Abfraction appears to be a modern condition, with examples of non-carious cervical lesions in the archaeological record typically caused by other factors. [1]

Contents

Definition

Abfraction Dental abrasion klinovidny de207.jpg
Abfraction

Abfraction is a form of non-carious tooth tissue loss that occurs along the gingival margin. [2] In other words, abfraction is a mechanical loss of tooth structure that is not caused by tooth decay, located along the gum line. There is theoretical evidence to support the concept of abfraction, but little experimental evidence exists. [3]

The term abfraction was first published in 1991 in a journal article dedicated to distinguishing the lesion. The article was titled "Abfractions: A New Classification of Hard Tissue Lesions of Teeth" by John O. Grippo. [4] This article introduced the definition of abfraction as a "pathologic loss of hard tissue tooth substance caused by bio mechanical loading forces". This article was the first to establish abfraction as a new form of lesion, differing from abrasion, attrition, and erosion. [2]

Tooth tissue is gradually weakened causing tissue loss through fracture and chipping or successively worn away leaving a non-carious lesion on the tooth surface. These lesions occur in both the dentine and enamel of the tooth. These lesions generally occur around the cervical areas of the dentition. [5]

Signs and symptoms

Figure 1 Abfraction lesion final.jpg
Figure 1

Abfraction lesions will generally occur in the region on the tooth where the greatest tensile stress is located. In statements such as these there is no comment on whether the lesions occur above or below the CEJ. One theory suggests that the abfraction lesions will only form above the CEJ. [6] [7] [8] [9] However, it is assumed that the abfraction lesions will occur anywhere in the cervical areas of affected teeth. It is important to note that studies supporting this configuration of abfraction lesions also state that when there is more than one abnormally large tensile stress on a tooth two or more abfraction lesions can result on the one surface. [3]

When looking at abfraction lesions there are generally three shapes in which they appear, appearing as either wedge, saucer or mixed patterns. [6] Wedge and saucer shaped lesions are the most common, whereas mixed lesions are less frequently identified in the oral cavity. [6] In reference to figure 1, wedge shaped lesions have the sharpest internal line angles and saucer/mixed shaped lesions are either smooth internally, or a variety.

Clinically, people with abfraction lesions can also present with tooth sensitivity in the associated areas. This occurs because as the abfraction lesions appear, dentine/cementum is exposed. [10] The dentine and cementum are less dense than tooth enamel and therefore more susceptible to sensation from thermal/mechanical sources. [10]

Causes

As abfraction is still a controversial theory there are various ideas on what causes the lesions. Because of this controversy the true causes of abfraction also remain disputable. [11] Researchers have proposed that abfraction is caused by forces on the tooth from the teeth touching together, occlusal forces, when chewing and swallowing. [4] [12] These lead to a concentration of stress and flexion at the area where the enamel and cementum meet (CEJ). [3] [5] This theoretical stress concentration [13] and flexion over time causes the bonds in the enamel of the tooth to break down and either fracture or be worn away from other stressors such as erosion or abrasion. [3] [5] [11] [12] The people who initially proposed the theory of abfraction believe the occlusal forces alone cause the lesions [13] without requiring the added abrasive components such as toothbrush and paste or erosion. [13]

If teeth come together in a non-ideal bite the researchers state that this would create further stress in areas on the teeth. [12] Teeth that come together too soon or come under more load than they are designed for could lead to abfraction lesions. [12] The impacts of restorations on the chewing surfaces of the teeth being the incorrect height has also been raised as another factor adding to the stress at the CEJ. [11]

Further research has shown that the normal occlusal forces from chewing and swallowing are not sufficient to cause the stress and flexion required to cause abfraction lesions. [3] However, these studies have shown that the forces are sufficient in a person who grinds their teeth (bruxism). [3] Several studies have suggested that it is more common among those who grind their teeth, [11] [13] as the forces are greater and of longer duration. Yet further studies have shown that these lesions do not always appear in people with bruxism and others without bruxism have these lesions. [5]

There are other researchers who would state that occlusal forces have nothing to do with the lesions along the CEJ and that it is the result of abrasion from toothbrush with toothpaste that causes these lesions. [3] [5] [11]

Being theoretical in nature there is more than one idea on how abfraction presents clinically in the mouth. One theory of its clinical features suggests that the lesions only form above the cementoenamel junction (CEJ) (which is where the enamel and cementum meet on a tooth). [6] [7] [8] [9] If this is kept in mind, it serves as a platform for it to be distinguished from other non-carious lesions, such as tooth-brush abrasion.

Treatment

Treatment of abfraction lesions can be difficult due to the many possible causes. To provide the best treatment option the dental clinician must determine the level of activity and predict possible progression of the lesion. [3] [13] A No.12 scalpel is carefully used by the dental clinician to make a small indentation on the lesion, this is then closely monitored for changes. Loss of a scratch mark signifies that the lesion is active and progressing.

It is usually recommended when an abfraction lesion is less than 1 millimeter, monitoring at regular intervals is a sufficient treatment option. If there are concerns around aesthetics or clinical consequences such as dentinal hypersensitivity, a dental restoration (white filling) may be a suitable treatment option.

Aside from restoring the lesion, it is equally important to remove any other possible causative factors. [2] Adjustments to the biting surfaces of the teeth alter the way the upper and lower teeth come together, this may assist by redirecting the occlusal load. [2] The aim of this is to redirect the force of the load to the long axis of the tooth, therefore removing the stress on the lesion. This can also be achieved by altering the tooth surfaces such as cuspal inclines, reducing heavy contacts and removing premature contacts. [2] If bruxism is deemed a contributing factor an occlusal splint can be an effective treatment for eliminating the irregular forces placed on the tooth. [3] [13]

Controversy

Abfraction has been a controversial subject since its creation in 1991. [11] This is due to the clinical presentation of the tooth loss, which often presents in a manner similar to that of abrasion or erosion. The major reasoning behind the controversy is the similarity of abfraction to other non carious lesions and the prevalence of multiple theories to potentially explain the lesion. One of the most prevalent theories is called "the theory of non-carious cervical lesions" which suggests that tooth flexion, occurring due to occlusion factors, impacts on the vulnerable area near the cementoenamel junction. [11] This theory is not widely accepted among the professional community as it suggests that the only factor is occlusion. Many researchers argue that this is inaccurate as they contend that the abfraction lesion is a multifactorial (has many causative factors) lesion with other factors such as abrasion or erosion. [5] This controversy around the causative factors, along with the recency of the lesion classification, are some of the reasons why many dental clinicians are looking at the lesion with some scepticism. More research is needed to fully clear up the controversy surrounding the abfraction lesion.

See also

Related Research Articles

<span class="mw-page-title-main">Human tooth</span> Calcified whitish structure in humans mouths used to break down food

Human teeth function to mechanically break down items of food by cutting and crushing them in preparation for swallowing and digesting. As such, they are considered part of the human digestive system. Humans have four types of teeth: incisors, canines, premolars, and molars, which each have a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food. The roots of teeth are embedded in the maxilla or the mandible and are covered by gums. Teeth are made of multiple tissues of varying density and hardness.

<span class="mw-page-title-main">Bruxism</span> Disorder that involves involuntarily grinding or clenching of the teeth

Bruxism is excessive teeth grinding or jaw clenching. It is an oral parafunctional activity; i.e., it is unrelated to normal function such as eating or talking. Bruxism is a common behavior; reports of prevalence range from 8% to 31% in the general population. Several symptoms are commonly associated with bruxism, including aching jaw muscles, headaches, hypersensitive teeth, tooth wear, and damage to dental restorations. Symptoms may be minimal, without patient awareness of the condition. If nothing is done, after a while many teeth start wearing down until the whole tooth is gone.

<span class="mw-page-title-main">Cementum</span> Specialized calcified substance covering the root of a tooth

Cementum is a specialized calcified substance covering the root of a tooth. The cementum is the part of the periodontium that attaches the teeth to the alveolar bone by anchoring the periodontal ligament.

<span class="mw-page-title-main">Tooth enamel</span> Major tissue that makes up part of the tooth in humans and many animals

Tooth enamel is one of the four major tissues that make up the tooth in humans and many animals, including some species of fish. It makes up the normally visible part of the tooth, covering the crown. The other major tissues are dentin, cementum, and dental pulp. It is a very hard, white to off-white, highly mineralised substance that acts as a barrier to protect the tooth but can become susceptible to degradation, especially by acids from food and drink. In rare circumstances enamel fails to form, leaving the underlying dentin exposed on the surface.

<span class="mw-page-title-main">Tooth decay</span> Deformation of teeth due to acids produced by bacteria

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.

<span class="mw-page-title-main">Dentin</span> Calcified tissue of the body; one of the four major components of teeth

Dentin or dentine is a calcified tissue of the body and, along with enamel, cementum, and pulp, is one of the four major components of teeth. It is usually covered by enamel on the crown and cementum on the root and surrounds the entire pulp. By volume, 45% of dentin consists of the mineral hydroxyapatite, 33% is organic material, and 22% is water. Yellow in appearance, it greatly affects the color of a tooth due to the translucency of enamel. Dentin, which is less mineralized and less brittle than enamel, is necessary for the support of enamel. Dentin rates approximately 3 on the Mohs scale of mineral hardness. There are two main characteristics which distinguish dentin from enamel: firstly, dentin forms throughout life; secondly, dentin is sensitive and can become hypersensitive to changes in temperature due to the sensory function of odontoblasts, especially when enamel recedes and dentin channels become exposed.

Dental restoration, dental fillings, or simply fillings are treatments used to restore the function, integrity, and morphology of missing tooth structure resulting from caries or external trauma as well as to the replacement of such structure supported by dental implants. They are of two broad types—direct and indirect—and are further classified by location and size. A root canal filling, for example, is a restorative technique used to fill the space where the dental pulp normally resides.

<span class="mw-page-title-main">Cementoenamel junction</span>

Cementoenamel junction (CEJ) is defined as the area of the union of cementum and enamel at the cervical region of the tooth. It is a slightly visible anatomical border identified on a tooth. It is the location where the enamel, which covers the anatomical crown of a tooth, and the cementum, which covers the anatomical root of a tooth, meet. Informally it is known as the neck of the tooth. The border created by these two dental tissues has much significance as it is usually the location where the gingiva attaches to a healthy tooth by fibers called the gingival fibers.

<span class="mw-page-title-main">Dental abrasion</span> Medical condition

Abrasion is the non-carious, mechanical wear of tooth from interaction with objects other than tooth-tooth contact. It most commonly affects the premolars and canines, usually along the cervical margins. Based on clinical surveys, studies have shown that abrasion is the most common but not the sole aetiological factor for development of non-carious cervical lesions (NCCL) and is most frequently caused by incorrect toothbrushing technique.

<span class="mw-page-title-main">Dental erosion</span> Medical condition

Acid erosion is a type of tooth wear. It is defined as the irreversible loss of tooth structure due to chemical dissolution by acids not of bacterial origin. Dental erosion is the most common chronic condition of children ages 5–17, although it is only relatively recently that it has been recognised as a dental health problem. There is generally widespread ignorance of the damaging effects of acid erosion; this is particularly the case with erosion due to consumption of fruit juices because they tend to be considered as healthy. Acid erosion begins initially in the enamel, causing it to become thin, and can progress into dentin, giving the tooth a dull yellow appearance and leading to dentin hypersensitivity.

<span class="mw-page-title-main">Periodontal fiber</span> Group of specialized connective tissue fibers

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 on one side and onto alveolar bone on the other.

<span class="mw-page-title-main">Human tooth development</span> Process by which teeth form

Tooth development or odontogenesis is the complex process by which teeth form from embryonic cells, grow, and erupt into the mouth. For human teeth to have a healthy oral environment, all parts of the tooth must develop during appropriate stages of fetal development. Primary (baby) teeth start to form between the sixth and eighth week of prenatal development, and permanent teeth begin to form in the twentieth week. If teeth do not start to develop at or near these times, they will not develop at all, resulting in hypodontia or anodontia.

<span class="mw-page-title-main">Dentinogenesis imperfecta</span> Medical condition

Dentinogenesis imperfecta (DI) is a genetic disorder of tooth development. It is inherited in an autosomal dominant pattern, as a result of mutations on chromosome 4q21, in the dentine sialophosphoprotein gene (DSPP). It is one of the most frequently occurring autosomal dominant features in humans. Dentinogenesis imperfecta affects an estimated 1 in 6,000-8,000 people.

Dentin hypersensitivity is dental pain which is sharp in character and of short duration, arising from exposed dentin surfaces in response to stimuli, typically thermal, evaporative, tactile, osmotic, chemical or electrical; and which cannot be ascribed to any other dental disease.

<span class="mw-page-title-main">Dental attrition</span>

Dental attrition is a type of tooth wear caused by tooth-to-tooth contact, resulting in loss of tooth tissue, usually starting at the incisal or occlusal surfaces. Tooth wear is a physiological process and is commonly seen as a normal part of aging. Advanced and excessive wear and tooth surface loss can be defined as pathological in nature, requiring intervention by a dental practitioner. The pathological wear of the tooth surface can be caused by bruxism, which is clenching and grinding of the teeth. If the attrition is severe, the enamel can be completely worn away leaving underlying dentin exposed, resulting in an increased risk of dental caries and dentin hypersensitivity. It is best to identify pathological attrition at an early stage to prevent unnecessary loss of tooth structure as enamel does not regenerate.

Dental anatomy is a field of anatomy dedicated to the study of human tooth structures. The development, appearance, and classification of teeth fall within its purview. Tooth formation begins before birth, and the teeth's eventual morphology is dictated during this time. Dental anatomy is also a taxonomical science: it is concerned with the naming of teeth and the structures of which they are made, this information serving a practical purpose in dental treatment.

Dental pertains to the teeth, including dentistry. Topics related to the dentistry, the human mouth and teeth include:

<span class="mw-page-title-main">Tooth wear</span> Medical condition

Tooth wear refers to loss of tooth substance by means other than dental caries. Tooth wear is a very common condition that occurs in approximately 97% of the population. This is a normal physiological process occurring throughout life; but with increasing lifespan of individuals and increasing retention of teeth for life, the incidence of non-carious tooth surface loss has also shown a rise. Tooth wear varies substantially between people and groups, with extreme attrition and enamel fractures common in archaeological samples, and erosion more common today.

<span class="mw-page-title-main">Tooth mobility</span> Medical condition

Tooth mobility is the horizontal or vertical displacement of a tooth beyond its normal physiological boundaries around the gingival area, i.e. the medical term for a loose tooth.

<span class="mw-page-title-main">Non-carious cervical lesions</span> Dental condition

Non-carious cervical lesions (NCCLs) are a group of lesions that are characterised by a loss of hard dental tissue at the cementoenamel junction (CEJ) region at the neck of the tooth, without the action of microorganisms or inflammatory processes. These lesions vary in shape from regular depressions that look like a dome or a cup, to deep wedge-shaped defects with the apex pointing inwards. NCCLs can occur either above or below the level of the gum, at any of the surfaces of the teeth.

References

  1. ↑ Towle, Ian; Irish, Joel D.; Elliott, Marina; De Groote, Isabelle (2018). "Root grooves on two adjacent anterior teeth of Australopithecus africanus" (PDF). International Journal of Paleopathology. 22: 163–167. doi:10.1016/j.ijpp.2018.02.004. PMID   30126662 . Retrieved 2019-01-09.
  2. 1 2 3 4 5 Bartlett, D.W.; Shah, P (April 2006). "A Critical Review of Non-carious Cervical (Wear) Lesions and the Role of Abfraction, Erosion, and Abrasion". Journal of Dental Research. 85 (4): 306–312. doi:10.1177/154405910608500405. PMID   16567549. S2CID   41159919.
  3. 1 2 3 4 5 6 7 8 9 Michael, JA; Townsend, GC; Greenwood, LF; Kaidonis, JA (March 2009). "Abfraction: separating fact from fiction". Australian Dental Journal. 54 (1): 2–8. doi:10.1111/j.1834-7819.2008.01080.x. PMID   19228125.
  4. 1 2 Grippo, John O (January–February 1991). "Abfractions: A New Classification of Hard Tissue Lesions of Teeth". Journal of Esthetic and Restorative Dentistry. 3 (1): 14–19. doi:10.1111/j.1708-8240.1991.tb00799.x. PMID   1873064.
  5. 1 2 3 4 5 6 Sarode, Gargi S; Sarode, Sachin C (May 2013). "Abfraction: A review". Journal of Oral and Maxillofacial Pathology. 17 (2): 222–227. doi: 10.4103/0973-029X.119788 . PMC   3830231 . PMID   24250083.
  6. 1 2 3 4 Hur, B; Kim, HC; Park, JK; Versluis, A (2011). "Characteristics of non-carious cervical lesions – an ex vivo study using micro computed tomography". Journal of Oral Rehabilitation. 38 (6): 469–74. doi:10.1111/j.1365-2842.2010.02172.x. PMID   20955394.
  7. 1 2 Lee, HE; Lin, CL; Wang, CH; Cheng, CH; Chang, CH (2002). "Stresses at the cervical lesion of maxillary premolar—a finite element investigation". Journal of Dentistry. 30 (7): 283–90. doi:10.1016/s0300-5712(02)00020-9. PMID   12554108.
  8. 1 2 Dejak, B; Młotkowski, A; Romanowicz, M (2003). "Finite element analysis of stresses in molars during clenching and mastication". Journal of Prosthetic Dentistry. 90 (6): 591–7. doi:10.1016/j.prosdent.2003.08.009. PMID   14668761. S2CID   25816890.
  9. 1 2 Borcic, J; Anic, I; Smojver, I; Catic, A; Miletic, I; Ribaric, SP (2005). "3D finite element model and cervical lesion formation in normal occlusion and in malocclusion". Journal of Oral Rehabilitation. 32 (7): 504–10. doi:10.1111/j.1365-2842.2005.01455.x. PMID   15975130.
  10. 1 2 Bamise, Cornelius T.; Olusile, Adeyemi O.; Oginni, Adeleke O. (2008). "An Analysis of the Etiological and Predisposing Factors Related to Dentin Hypersensitivity". The Journal of Contemporary Dental Practice. 9 (5): 9.
  11. 1 2 3 4 5 6 7 Antonelli JR, Hottel TL, Garcia-Godoy F. Abfraction Lesions – Where do They Come From? A Review of the Literature. J Tenn Dent Assoc. 2013; 93(1):14-19
  12. 1 2 3 4 Grippo, JO; Simring, M; Coleman, TA (2012). "Abfraction, Abrasion, Biocorrosion, and the Enigma of Noncarious Cervical Lesions: A 20-Year Perspective". Journal of Esthetic and Restorative Dentistry. 24 (1): 10–23. doi:10.1111/j.1708-8240.2011.00487.x. PMID   22296690.
  13. 1 2 3 4 5 6 Shetty, SM; Shetty, RG; Mattigatti, S; Managoli, NA; Rairam, SG; Patil, AM (2013). "No Carious Cervical Lesions". J Int Oral Health. 5 (5): 142–145.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.