[Summary] Marsupialization or decompression of the cystic lesions of the jaws is the technique that relieves the pressure within the cyst and causes some decrease in size of the lesion, so that subsequent enucleation ...[Summary] Marsupialization or decompression of the cystic lesions of the jaws is the technique that relieves the pressure within the cyst and causes some decrease in size of the lesion, so that subsequent enucleation or curettage could be performed more simply and with less risk to adjacent vital structures. A permanent tooth in the dentigerous cyst in preadolescents often erupts successfully after marsupialization and resolution of the cyst. Large odontogenic keratocyst or unicystic ameloblastoma is marsupialized initially and then enucleated at a later stage, reducing the possibility of pathological fracture of the mandible or the need for jaw resection. However, it should be kept in mind that a few of odontogenic keratocysts or unicystic ameloblastomas still may recur after this two- stage procedure and multi - cystic amelobalstoma has a high recurrence rate and a potential to infiltrate into the surrounding tissues.展开更多
Keratocystic odontogenic tumors(KCOTs,previously known as odontogenic keratocysts) are aggressive,noninflammatory jaw lesions with a putative high growth potential and a propensity for recurrence.This article puts tog...Keratocystic odontogenic tumors(KCOTs,previously known as odontogenic keratocysts) are aggressive,noninflammatory jaw lesions with a putative high growth potential and a propensity for recurrence.This article puts together a summary of the serial studies related to KCOTs undertaken by the author’s research group in recent years.Intraosseous jaw cysts with a solely orthokeratinized lining epithe-lium have been suggested to differ from the typical KCOTs.We report 20 cases of such cyst type under the term of ’orthokeratinized odontogenic cyst(OOC)’.Apart from the presence of a keratinizing epithelial lining,the OOC lacks the other histological features of KCOT,exhibits little if any tendency to recur,has no apparent association with NBCCS,may be cured by simple enucleation,and may thus constitute its own clinical entity.Mutations in PTCH1 gene are responsible for NBCCS and are related in tumors associated with this syndrome.We have so far detected 26 PTCH1 mutations(2 mutations occurred twice) in 10 out of 34(29.4%) sporadic and 14 out of 16(87.5%) NBCCS-associated KCOTs.The 26 mutations consisted of 10 frameshift,2 nonsense,3 aberrant splicing,4 in-frame insertion/deletion/ duplication and 7 missense mutations.Two missense mutations in PTCH2 were also detected in 2 out of 15 NBCCS related KCOT patients.By contrast,no pathogenic mutation was detected in SMO.Thus,our data,together with reports from ther groups,indicate that defects of PTCH1 are involved in the pathogenesis of syndromic as well as sporadic KCOTs.The pathogenic role of PTCH2 requires further investigation.A series of in vitro studies on bone resorption of KCOTs and ameloblastomas were undertaken by this group.The results indicate that odontogenic lesions could promote bone resorption in vitro and it is likely to be related to some of the cytokines secreted by the lesions.展开更多
The jaw bones are the most common sites for epithelial cysts and tumors in the human skeleton due to their close relationship to the tooth and odontogenesis. Most of these cysts and tumors have in common an origin fro...The jaw bones are the most common sites for epithelial cysts and tumors in the human skeleton due to their close relationship to the tooth and odontogenesis. Most of these cysts and tumors have in common an origin from the tissues of tooth formation and constitute a very diverse group of lesions that reflects the complex development of the dental structures. This group of odontogenic lesions occurs predominantly in the jaws, with a predilection for young people. Some aggressive lesions have attracted much attention as they often produce marked facial deformity and tend to recur after insufficient surgery. The most widely quoted classification of odontogenic tumors is that proposed in the WHO booklet published in 1992. There are, however, a number of controversial issues that need to be addressed with respect to clinicopathological subtypings, terminology, and diagnosis which all have direct bearings on therapeutic and/or prognostic implications. In the light of recent publication of the WHO new classification and a series of related studies undertaken by the author’s group, this paper is to put together an overview on some of these important aspects related to unicystic ameloblastoma, clear cell odontogenic tumor, calcifying odontogenic cyst, odontogenic keratocyst, ameloblastic fibroma and its related lesions. Consequent upon a better understanding of the nature of these tumors and their variants, the various treatment protocols currently recommended by different surgeons will be better rationalized.展开更多
文摘[Summary] Marsupialization or decompression of the cystic lesions of the jaws is the technique that relieves the pressure within the cyst and causes some decrease in size of the lesion, so that subsequent enucleation or curettage could be performed more simply and with less risk to adjacent vital structures. A permanent tooth in the dentigerous cyst in preadolescents often erupts successfully after marsupialization and resolution of the cyst. Large odontogenic keratocyst or unicystic ameloblastoma is marsupialized initially and then enucleated at a later stage, reducing the possibility of pathological fracture of the mandible or the need for jaw resection. However, it should be kept in mind that a few of odontogenic keratocysts or unicystic ameloblastomas still may recur after this two- stage procedure and multi - cystic amelobalstoma has a high recurrence rate and a potential to infiltrate into the surrounding tissues.
文摘Keratocystic odontogenic tumors(KCOTs,previously known as odontogenic keratocysts) are aggressive,noninflammatory jaw lesions with a putative high growth potential and a propensity for recurrence.This article puts together a summary of the serial studies related to KCOTs undertaken by the author’s research group in recent years.Intraosseous jaw cysts with a solely orthokeratinized lining epithe-lium have been suggested to differ from the typical KCOTs.We report 20 cases of such cyst type under the term of ’orthokeratinized odontogenic cyst(OOC)’.Apart from the presence of a keratinizing epithelial lining,the OOC lacks the other histological features of KCOT,exhibits little if any tendency to recur,has no apparent association with NBCCS,may be cured by simple enucleation,and may thus constitute its own clinical entity.Mutations in PTCH1 gene are responsible for NBCCS and are related in tumors associated with this syndrome.We have so far detected 26 PTCH1 mutations(2 mutations occurred twice) in 10 out of 34(29.4%) sporadic and 14 out of 16(87.5%) NBCCS-associated KCOTs.The 26 mutations consisted of 10 frameshift,2 nonsense,3 aberrant splicing,4 in-frame insertion/deletion/ duplication and 7 missense mutations.Two missense mutations in PTCH2 were also detected in 2 out of 15 NBCCS related KCOT patients.By contrast,no pathogenic mutation was detected in SMO.Thus,our data,together with reports from ther groups,indicate that defects of PTCH1 are involved in the pathogenesis of syndromic as well as sporadic KCOTs.The pathogenic role of PTCH2 requires further investigation.A series of in vitro studies on bone resorption of KCOTs and ameloblastomas were undertaken by this group.The results indicate that odontogenic lesions could promote bone resorption in vitro and it is likely to be related to some of the cytokines secreted by the lesions.
文摘The jaw bones are the most common sites for epithelial cysts and tumors in the human skeleton due to their close relationship to the tooth and odontogenesis. Most of these cysts and tumors have in common an origin from the tissues of tooth formation and constitute a very diverse group of lesions that reflects the complex development of the dental structures. This group of odontogenic lesions occurs predominantly in the jaws, with a predilection for young people. Some aggressive lesions have attracted much attention as they often produce marked facial deformity and tend to recur after insufficient surgery. The most widely quoted classification of odontogenic tumors is that proposed in the WHO booklet published in 1992. There are, however, a number of controversial issues that need to be addressed with respect to clinicopathological subtypings, terminology, and diagnosis which all have direct bearings on therapeutic and/or prognostic implications. In the light of recent publication of the WHO new classification and a series of related studies undertaken by the author’s group, this paper is to put together an overview on some of these important aspects related to unicystic ameloblastoma, clear cell odontogenic tumor, calcifying odontogenic cyst, odontogenic keratocyst, ameloblastic fibroma and its related lesions. Consequent upon a better understanding of the nature of these tumors and their variants, the various treatment protocols currently recommended by different surgeons will be better rationalized.