ameloblast

49) These findings suggest an interesting hypothesis: an excess in cytoplasmic F- in ameloblast induces stress in the endoplasmic reticulum and activates a defense called "unfolded protein response" (UPR), which decreases the synthesis and secretion of KLK-4, essential for the elimination of the protein matrix of amelogenin and the final maturation of enamel prisms.

Other possible causes suggested are: environmen- tal conditions, premature birth, perinatal compli- cations, exposure to dioxine by prolonged breast- feeding, respiratory diseases and oxygen shortage of the ameloblasts, calcium and phosphate meta- bolic troubles, oxygen starvation associated to low birth weight and febrile childhood diseases.

In marsupials, tubules are described as hollow spaces formed by the course of ameloblasts, occurring within or outside of prisms, and sometimes continuous with dentine tubules across the enamel-dentine junction (Boyde and Lester, 1967).

Development of enamel is a complex organized process, where the ameloblasts lay down the enamel rods in an undulating and inter-twining path.

Expression of Notch 1,2 and 3 is regulated by epithelial-mesenchymal interactions and retinoic acid in the developing mouse tooth and associated with determination of ameloblast cell fate.

It is the consequence of insults to the highly specialised and vulnerable ameloblast cells, apparently during the later mineralisation phase of amelogenesis resulting in defective enamel with significantly increased protein content [Farah et al.

Ameloblastoma is an odontogenic tumour of epi-thelial origin and is composed of ameloblast like cell.

Amelogenesis has been divided into three major stages of the ameloblast life cycle, namely secretory, transition, and maturation.

Incisional biopsy of the lesion was performed and microscopic examination revealed odontogenic epithelial cells proliferating in broad anastomosing cords showing presence of peripheral tall columnar ameloblast like cells with reverse nuclear polarity and central stellate reticulum like cells.

Effects of a macrolide antibiotic on enamel formation in rat incisors--primary lesion of ameloblast at the transition stage.

The epithelial stem cells divide asymmetrically into two cells; the first, called the sister cell, remains in the apical loop and is undifferentiated; the second moves towards the incisive margin and serves as the source of ameloblasts.

Ameloblasts are cells present during tooth development that secrete large amounts of proteins that later mineralize to form tooth enamel.

Ameloblasts within the developing tooth germ are very sensitive to external stimuli, and many factors can result in enamel abnormalities.

The process of amelogenesis is a complex and regulated by ameloblasts that requires secretion of certain matrix proteins that includes amelogenins, amelins, enamelins and tuftelins and the previously formed dentine.

The enamel is produced by ameloblasts (Figure 2D) originated from the inner epithelium of the enamel organ, which is originated from the dental lamina.