Role of reduced enamel epithelium in root resorption

The aim of this paper is to provide a review on the role of inflammation in orthodontically induced inflammatory root resorption (OIIRR) and accelerating orthodontic tooth movement (AOTM) in orthodontic treatment. Orthodontic tooth movement (OTM) is stimulated by remodeling of the periodontal ligament (PDL) and alveolar bone. These remodeling activities and tooth displacement are involved in the occurrence of an inflammatory process in the periodontium, in response to orthodontic forces. Inflammatory mediators such as prostaglandins (PGs), interleukins (Ils; IL-1, -6, -17), the tumor necrosis factor (TNF)-α superfamily, and receptor activator of nuclear factor (RANK)/RANK ligand (RANKL)/osteoprotegerin (OPG) are increased in the PDL during OTM. OIIRR is one of the accidental symptoms, and inflammatory mediators have been detected in resorbed roots, PDL, and alveolar bone exposed to heavy orthodontic force. Therefore, these inflammatory mediators are involved with the occurrence of OIIRR during orthodontic tooth movement. On the contrary, regional accelerating phenomenon (RAP) occurs after fractures and surgery such as osteotomies or bone grafting, and bone healing is accelerated by increasing osteoclasts and osteoblasts. Recently, tooth movement after surgical procedures such as corticotomy, corticision, piezocision, and micro-osteoperforation might be accelerated by RAP, which increases the bone metabolism. Therefore, inflammation may be involved in accelerated OTM (AOTM). The knowledge of inflammation during orthodontic treatment could be used in preventing OIIRR and AOTM.

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Lesions of the Enamel Organ of Developing Dog Teeth following Experimental Inoculation of Gnotobiotic Puppies with Canine Distemper Virus

Veterinary Pathology ◽

10.1177/030098588101800513 ◽

1981 ◽

Vol 18 (5) ◽

pp. 684-689 ◽

Cited By ~ 19

Author(s):

R. R. Dubielzig ◽

R. J. Higgins ◽

S. Krakowka

Keyword(s):

Canine Distemper Virus ◽

Giant Cells ◽

Enamel Organ ◽

Post Inoculation ◽

Canine Distemper ◽

Experimental Inoculation ◽

Enamel Epithelium ◽

Viral Inclusions ◽

Reduced Enamel Epithelium ◽

Multinucleate Giant Cells

Ten 7-day-old gnotobiotic Beagle puppies were inoculated intraperitoneally with virulent canine distemper virus (R252-CDV). The dogs were killed and perfused with paraformaldehyde/glutaraldehyde from eight to 36 days after inoculation. The developing teeth of the mandibles were examined by light microscopy, and the teeth from three dogs were examined by electron microscopy. Necrosis of individual cells in the stratum intermedium of the developing tooth was the first change, detectable at day 9 post-inoculation. At day 16 post-inoculation, there was disorganization of the ameloblasts. In the stratum intermedium, multinucleate giant cells and large eosinophilic cytoplasmic viral inclusions were prominent. Ultrastructurally, these inclusions consisted of clusters of tubular aggregates typical of canine distemper virus nucleocapsids. At 28 to 36 days post-inoculation, the changes were seen in the reduced enamel epithelium. Multinucleate cells were seen, but no inclusions. Some necrotic cells were seen. In these teeth, ameloblastic cells of the root were morphologically normal. Our results suggest that distemper virus affects developing teeth by direct infection of the enamel organ.

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Pericoronal Follicles of Asymptomatic Impacted Teeth: A Radiographic, Histomorphologic, and Immunohistochemical Study

International Journal of Dentistry ◽

10.1155/2012/935310 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 6

Author(s):

Laura Villalba ◽

Federico Stolbizer ◽

Fabián Blasco ◽

Néstor Raúl Mauriño ◽

María Julia Piloni ◽

...

Keyword(s):

Cell Proliferation ◽

Immunohistochemical Study ◽

Squamous Metaplasia ◽

Ki 67 ◽

Impacted Teeth ◽

Positive Expression ◽

Dentigerous Cysts ◽

Proliferation And Apoptosis ◽

Enamel Epithelium ◽

Reduced Enamel Epithelium

Objective. To associate radiographic and histopathological features of pericoronal follicles (PFs) of asymptomatic impacted teeth and evaluate cell proliferation and apoptosis in the epithelium.Study Design. Epithelium and mesenchyme of radiographically normal (NPF≤2.5 mm) and hyperplastic (HPF 2.6 to 5 mm) PF (n=140) were studied histologically. Cell proliferation (PI) and epithelial apoptosis were evaluated by Ki-67 and bcl-2 expression in 14 NPFs and 10 dentigerous cysts (DCs).Results. Radiographically, 127 were NPFs and 13 were HPFs; 87.8% of total PFs exhibited epithelium on the surface. Reduced enamel epithelium was observed in 78 (61.4%) NPFs and 6 (46.2%) HPFs, squamous metaplasia in 17 (13.4%) NPFs and 4 (30.8%) HPFs, and cystic epithelium in 15 (11.8%) NPFs and 3 (23%) HPFs. Mean PI was1.97±1.25and7.97±1.74in the epithelial component of NPF and DC, respectively; bcl-2 positive expression was observed in 9 (64.3%) NPFs and 7 (70%) DCs.Conclusion. The scant epithelial remnant proliferation could imply low risk for development of odontogenic pathologies in the absence of an additional stimulus.

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Signaling Pathways Critical for Tooth Root Formation

Journal of Dental Research ◽

10.1177/0022034517717478 ◽

2017 ◽

Vol 96 (11) ◽

pp. 1221-1228 ◽

Cited By ~ 25

Author(s):

J. Wang ◽

J.Q. Feng

Keyword(s):

Signaling Pathways ◽

Root Formation ◽

Root Resorption ◽

Tooth Development ◽

Critical Role ◽

Future Research ◽

Tooth Root ◽

Short Root ◽

Dentin Formation

Tooth is made of an enamel-covered crown and a cementum-covered root. Studies on crown dentin formation have been a major focus in tooth development for several decades. Interestingly, the population prevalence for genetic short root anomaly (SRA) with no apparent defects in crown is close to 1.3%. Furthermore, people with SRA itself are predisposed to root resorption during orthodontic treatment. The discovery of the unique role of Nfic (nuclear factor I C; a transcriptional factor) in controlling root but not crown dentin formation points to a new concept: tooth crown and root have different control mechanisms. Further genetic mechanism studies have identified more key molecules (including Osterix, β-catenin, and sonic hedgehog) that play a critical role in root formation. Extensive studies have also revealed the critical role of Hertwig’s epithelial root sheath in tooth root formation. In addition, Wnt10a has recently been found to be linked to multirooted tooth furcation formation. These exciting findings not only fill the critical gaps in our understanding about tooth root formation but will aid future research regarding the identifying factors controlling tooth root size and the generation of a whole “bio-tooth” for therapeutic purposes. This review starts with human SRA and mainly focuses on recent progress on the roles of NFIC-dependent and NFIC-independent signaling pathways in tooth root formation. Finally, this review includes a list of the various Cre transgenic mouse lines used to achieve tooth root formation–related gene deletion or overexpression, as well as strengths and limitations of each line.

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Role of polymorphism of the interleukin-1B gene and other genetic polymorphisms in the aetiology of root resorption in patients receiving orthodontic treatment

Forum Ortodontyczne ◽

10.5604/01.3001.0010.2604 ◽

2017 ◽

Vol 13 (1) ◽

pp. 36-42

Author(s):

Marzena Makowska-Kaczmarska ◽

Anna Okoń ◽

Elżbieta Olszewska

Keyword(s):

Genetic Polymorphisms ◽

Gene Polymorphisms ◽

Orthodontic Treatment ◽

Potential Role ◽

Root Resorption ◽

Interleukin 1 ◽

Dna Testing ◽

Individual Gene ◽

Global Population

Aim. The aim of the work was to present the latest directions in the research on gene polymorphisms in the global population and to discuss their potential role in the pathogenesis of root resorption during orthodontic treatment. Material and methods. A review of the literature in Polish and English from the years 1990–2015 was conducted using PubMed/MEDLINE databases and the results of studies kept in the database of the National Centre for Biotechnology Information were used. Key words used: genetics of root resorption, genetic polymorphism, interleukin-1B. Results. 19 articles were analysed. Special attention was placed on the latest studies on the human genome, especially focused on gene polymorphisms in the global population. Summary. Pathogenesis of root resorption during orthodontic treatment is complex. Its background is undoubtedly genetic. Gene polymorphism is important. The role of polymorphism of the interleukin-1B gene and other genes in the interleukin-1 cluster draws special attention. Identification of genetic factors that play an important role in the aetiology of root resorption may in the future help to identify patients susceptible to such complications even before the beginning of orthodontic treatment. Potential possibilities of DNA testing in clinical practice are enormous. The role of individual gene polymorphisms in the pathogenesis of root resorption has not been yet explained in detail and further multicentre studies are necessary. At this stage of studies no reliable markers have been detected in order to predict which patients would develop this complication. (Makowska- Kaczmarska M, Okoń A, Olszewska E. Role of polymorphism of the interleukin-1B gene and other genetic polymorphisms in the aetiology of root resorption in patients receiving orthodontic treatment. Orthod Forum 2017; 13: 36-42).

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Management of Dentigerous Cyst: A Review Article

Journal of Clinical Surgery and Research ◽

10.31579/2768-2757/009 ◽

2021 ◽

Vol 2 (1) ◽

pp. 01-04

Author(s):

Nanda Gofur

Keyword(s):

Epithelial Cells ◽

Dentigerous Cyst ◽

Inflammatory Cells ◽

Cyst Fluid ◽

Enamel Organ ◽

Fluid Accumulation ◽

Venous Flow ◽

Dentigerous Cysts ◽

Enamel Epithelium ◽

Reduced Enamel Epithelium

Introduction: Dentigerous cyst is a pathological epithelial cavity that surrounds an unerupted tooth crown. Dentigerous cysts are usually associated with impacted teeth, mandibular third molars, first and second premolars and canines. Dentigerous cysts can occur at any age, but most cases of these cysts occur at the age of approximately 20 years. Men are affected more often than women. Purpose.To find out how the mechanism of dentigerous cysts. The cyst cavity is lined with epithelial cells derived from the epithelial enamel that is reduced from the tooth-forming organs. According to its pathogenesis, the pressure exerted by an erupted tooth on the follicle can block venous flow leading to accumulation of exudate between the reduced enamel epithelium and the crown of the tooth. These cysts are mostly due to fluid accumulation either between the reduced enamel epithelium and the enamel or between the layers of the enamel organ. This fluid accumulation occurs as a result of the pressure exerted by the erupting tooth on the affected follicle, which blocks venous flow, thus inducing rapid transudation of serum in the capillary walls. Discussion: The expansion of the dentigerous cyst causes the release of bone resorbing factor and an increase in the osmolarity of the cyst fluid as a result of the discharge of inflammatory cells, the discharge of residual epithelial enamel and tooth enamel, and desquamation of epithelial cells into the lumen of the cyst. In theory, the fluid will cause cystic proliferation. because the hyperosmolar content produced by cellular breakdown and cell products causes an osmotic gradient to pump fluid into the lumen of the cyst or it can also be said that an increase in the osmolarity of cyst fluid is the result of a shortcut to inflammatory cells and desquamation of epithelial cells into the lumen of the cyst resulting in a dentigerous cyst. Conclusion: The dentigerous cysts that surround the unerupted dental crowns are caused by the accumulation of fluid either between the reduced enamel epithelium or between the layers of the enamel organs. Dentigerous cysts can cause infection, pain, swelling, root dislocation, and resorption of adjacent tooth roots.

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Bilateral ectopic third molar in the maxillary sinuses associated with dentigerous cyst: a case report

Medicine and Pharmacy Reports ◽

10.15386/mpr-2072 ◽

2021 ◽

Author(s):

Antoine Berberi ◽

Georges Aoun ◽

Bouchra Hjeij ◽

Maissa AboulHosn ◽

Hiba Alassaad ◽

...

Keyword(s):

Dentigerous Cyst ◽

Third Molar ◽

Third Molars ◽

Unerupted Tooth ◽

Sinus Cavity ◽

Dentigerous Cysts ◽

Enamel Epithelium ◽

Ectopic Third Molar ◽

Reduced Enamel Epithelium ◽

Maxillary Sinuses

A dentigerous cyst is an epithelial-lined odontogenic cyst formed by an accumulation of fluid between the reduced enamel epithelium and the crown of an unerupted tooth. About 70% of dentigerous cysts occur in the mandible and 30% in the maxilla and the most involved teeth are maxillary canines and maxillary third molar. Dentigerous cysts often displace the related tooth into an ectopic position. In the maxilla when the cyst expands into the sinus, usually causes total or partial occupation of the sinus cavity and can extend to the nose. We report a rare case of a 24-year-old female with bilateral maxillary third molars inside the maxillary sinuses attached to a dentigerous cyst and treated with a minimally invasive endoscopic surgery through the middle meatal meatotomy.

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Dentigerous Cyst Associated with Mesiodens: A Symbiotic Existence

Journal of Oral Health and Community Dentistry ◽

10.5005/johcd-8-2-119 ◽

2014 ◽

Vol 8 (2) ◽

pp. 119-121

Author(s):

M Kamboj ◽

B Shreedhar ◽

G Srivastava ◽

D Verma

Keyword(s):

Male Patient ◽

Treatment Strategy ◽

Dentigerous Cyst ◽

Odontogenic Cyst ◽

Tooth Crown ◽

Supernumerary Tooth ◽

Upper Lip ◽

Unerupted Tooth ◽

Enamel Epithelium ◽

Reduced Enamel Epithelium

ABSTRACT Dentigerous cyst is a developmental odontogenic cyst that develops by accumulation of fluid between the reduced enamel epithelium and the tooth crown of unerupted tooth. Mesiodens is a supernumerary tooth between both maxillary central incisors. Dentigerous cyst associated with mesiodens is rare. This paper presents a case of dentigerous cyst associated with an inverted mesiodens causing a painless swelling in the upper lip of a 29 years old male patient along with the treatment strategy employed for the patient.

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