desmosomes are intercellular junctions that tether intermediate filaments ( ifs ) to the plasma membrane . desmogleins and desmocollins , members of the cadherin super family , mediate adhesion at desmosomes . it is an adhesive intercellular junction that is crucial to tissues that experience mechanical stress , such as the myocardium , bladder , gastrointestinal mucosa and skin . the desmosome was first observed in the spinous layer of epidermis by the italian pathologist giulio bizzozero ( 18461901 ) . bizzozero 's observations of these small dense nodules , subsequently named  nodes of bizzozero ,  led him to the insightful interpretation of these structures as adhesive cell  cell contact points . the term was coined by josef schaffer in 1920 ( schaffer , 1920 ) and derives from the greek word  desmos  , meaning  bond  ,  ligament  , or  fastening epithelial desmosomes are usually small ( 200350 nm ) , electron - dense , symmetrical , disk - like structures , which link the keratin if systems within cells to the plasma membrane and to adjacent cells [ figure 1 ] . desmosomes comprise of proteins from at least three distinct gene families : cadherins , armadillo proteins and plakin family of cytolinkers . cell junctions is a driving force for morphogenesis and cell positioning during development and for maintenance of tissue integrity in adult organisms . desmosomes together with adherens junctions represent the major adhesive cell  cell junctions of epithelial cells . they also link the if cytoskeletons between cells and play major role in cell signaling , tissue morphogenesis and wound repair . schematic representation of normal desmosomes ( courtesy : delva e , tucker dk , and kowalczyk ap . cold spring harb perspect biol 2009;1:a002543 ) desmosomes resist mechanical stress because they adopt a strongly adhesive state in which they are said to be hyperadhesive and which distinguishes them from other intercellular junctions ; desmosomes are specialized for strong adhesion and their failure can result in diseases of the skin and heart . the desmosomal if complex may be divided into three components , two intracellular and one intercellular . intracellularly there are the ifs that link with the the desmosomal adhesion molecules ; intercellularly there is the adhesive bond provided by the desmosomal adhesion molecules . they are also dynamic structures whose adhesiveness can switch between high and low affinity adhesive states during processes such as embryonic development and wound healing , the switching being signaled by protein kinase c. desmosomes may also act as signaling centers , regulating the availability of signaling molecules and thereby participating in fundamental processes such as cell proliferation , differentiation and morphogenesis . mutations in genes encoding desmosomal constituents can have devastating effects on tissue integrity , but it would be a mistake to assume that desmosomes are simply adhesive structures ; much evidence now indicates that they play an important part in the regulation of cell proliferation and differentiation . furthermore , there is a strong possibility that desmosomes influence epithelial cell invasion and metastasis . the three most commonly found odontogenic cysts were selected for the study , that is , radicular cyst ( rc ) , dentigerous cyst ( dc ) and odontogenic keratocyst ( okc ) and were studied for the desmosomal attachment . the okc has already been categorized as benign epithelial tumor according to the world health organization ( who ) classification of odontogenic tumors in 2005 . although all these lesions arise from odontogenic apparatus , okc behaves in an aggressive manner as compared to the other two lesions . the present study was designed to analyze the desmosomal junctions under light and electron microscope in okc , dc , rc and normal mucosa . the study aimed to analyze whether the desmosomes have any role to play in the aggressive behavior of okc as compared to the dentigerous and rc . the structural integrity of desmosomes was also analyzed by scanning electron microscopy ( sem ) . the present study was designed to analyze the desmosomal junctions under light and electron microscope in okc , dc , rc and normal mucosa . the study aimed to analyze whether the desmosomes have any role to play in the aggressive behavior of okc as compared to the dentigerous and rc . the structural integrity of desmosomes the study was conducted on 10 cases each of okc , dc , rc and normal mucosa that were retrieved from the archives of our department . the tissues were obtained on the slide by routine microtomy and stained with h and e. the stained sections were compared with the tissues of normal mucosa . sem is helpful in analyzing the surface morphology of tissues and is routinely used for hard tissue specimens . but , as our study included soft tissue specimens , the routine protocol could not be followed . the sections had to be thin , approximately of 34 m and absolutely free of moisture . also , the width of the section created problems as the area of interest tended to get lost . the area of interest , that is , the epithelium on h and e stained section was first marked and this marking was later superimposed onto the corresponding unstained section . this glass slide with unstained section was then cut into an approximately size of 1 cm  2 cm . the unstained section was then passed through various changes of xylene and brought to absolute alcohol . the slides were removed from alcohol just before sputtering , which is the initial step before sem analysis . h and e stained section of normal mucosa under 1000 magnification revealed numerous desmosomes between the epithelial cells [ figure 2 ] . the same field on sem analysis confirmed the findings and intact and numerous desmosomes were seen linking the epithelial cells [ figure 3 ] . however , an increase in the intercellular space was also noted [ figure 4 ] . sem analysis demonstrated similar findings with the presence of many desmosomes [ figure 5 ] , though they were seen to be damaged and fragile . h and e stained dc under 1000 did not show any desmosome [ figure 6 ] . sem analysis of the same confirmed the observation and very minimal number were seen with condensed arrangement of the epithelial cells [ figure 7 ] . rc at 1000 magnification in h and e sections revealed plenty of desmosomes , which were seen linking the epithelial cells [ figure 8 ] . desmosomes in normal oral mucosa ( h&e stain , x1000 ) scanning electron microscopy ( sem ) image of normal mucosa showing normal desmosomal junctions . ( 1700 ) fragile desmosomes in odontogenic keratocyst ( okc ) ( h&e stain , 1000 ) ) sem image of odontogenic keratocyst ( 2000 ) very few desmosomes in dentigerous cyst ( h&e stain , 1000 ) sem image of dentigerous cyst ( 3000 ) desmosomes as seen in radicular cyst ( h&e stain , 1000 ) sem image of desmosomes in radicular cyst ( 1600 ) desmosomes help in maintaining the structural integrity of the epithelium . they represent adherens type of junctions which hold the cells together , but the intercellular space in these junctions their loss and destruction is the reason for clinical behavior of various lesions , especially the skin lesions . in this study , rcs showed similar number of desmosomes as compared to the normal mucosa and they were seen to be intact for most part of the epithelium . in rcs , inflammation is a contributory factor for proliferation of the odontogenic epithelial lining . thereby , the desmosomal junctions seen were similar to those seen in normal mucosa . in case of dc , the desmosomes seen were very minimal in number and the epithelial cells were condensely packed together . this may be because of the increased pressure from the cystic fluid , which leads to compression of reduced enamel epithelial cells , making the intercellular junctions less evident . thus , the scanty number of desmosomes along with the compact arrangement of epithelial cells may explain the non recurrent behavior of dc . the number of desmosomes in okc was more as compared to others , but they were seen to be fragile and damaged at many places . this structural damage may attribute to the fragility of the epithelium which many a times is evident even at the light microscopic level in the form of splits ; especially at the basal and the suprabasilar levels . it has already been documented that these basal and the suprabasilar cells have the highest proliferative activity . loss of either desmocollin 1 ( dsc 1 ) , desmoglein 3 ( dsg3 ) , or desmoglein 4 ( dsg4 ) produces blistering phenotypes in mice due to loss of adhesion . in the case of dsc1 and dsg4 , the increased proliferation and alteration can be attributed to dsc1 and dsg4 in cases of okc . misexpression of either dsg3 or dsc3 in suprabasal layers of the epidermis , driven by the keratin 1 promoter , results in increased cell proliferation and altered differentiation . whether these changes in desmosomes in okc are a result of defective adhesion or are a consequence of altered desmosomal cadherin ratios in the cyst is uncertain . thus , we put forth the hypothesis that the loss of structural integrity could be the reason for fragility of epithelium in okc , which in turn leads to recurrence and aggressive clinical behavior of the cyst . desmosomes have evolved in parts to enable tissues like the heart , the skin and its appendages ( e.g. hair ) to withstand mechanical stress . consequently , when desmosomal adhesion is compromised through gene mutations these tissues are primarily affected . as more research is conducted on desmosomes , we are bound to further understand not only the physical nature of these junctions but also their prospective roles as signaling centers during development , homeostasis and disease . in our literature search we did not come across any studies focusing on the relationship of desmosomal junctions and odontogenic cysts . through this study , we have tried to analyze the desmosomes in various odontogenic cysts . the study revealed that there was an increase in number and prominent desmosomes observed in case of okc . however , the associated damage to the desmosomes seen helped us in postulating the theory that the structural damage may be responsible for friability and subsequent recurrence nature demonstrated by okc .
introduction : desmosomes together with adherens junctions represent the major adhesive cell  cell junctions of epithelial cells . 
 any damage to these junctions leads to loss of structural balance.aim:the present study was designed to analyze the desmosomal junctions in different odontogenic cysts and compare them with their corresponding hematoxylin and eosin ( h and e )   stained sections.materials and methods : ten cases each of odontogenic keratocyst ( okc ) , dentigerous cysts ( dcs ) , radicular cysts ( rcs ) and normal mucosa were stained with hematoxylin and eosin . scanning electron microscopy ( sem ) analysis of the sections was then carried out of all the sections . 
 the area of interest on h and e stained section was marked and this marking was later superimposed onto the corresponding unstained sections and were subjected to sem analysis.results and observations : okc at 1000 magnification showed many prominent desmosomes . 
 however , an increase in the intercellular space was also noted . 
 sem analysis demonstrated similar findings with the presence of many desmosomes , though they were seen to be damaged and fragile . 
 h and e stained dc under oil immersion did not show any prominent desmosomes . 
 sem analysis of the same confirmed the observation and very minimal number were seen with a very condense arrangement of the epithelial cells . 
 rc at 1000 magnification revealed plenty of desmosomes , which were again confirmed by sem.conclusion:the number and quality of desmosomal junctions in all the cysts has a role in the clinical behavior of the cyst .