ABSTRACT
The digastric muscle is a suprahyoid muscle composed of two bellies connected by an intermediate tendon.This muscle participates in deglutition and mandibular movements. The anterior belly of the digastric muscleis localized superficially to the mylohyoid and deeply to the platysma muscle. During dissection of this regionof an embedded cadaver, an accessory anterior belly of digastric muscle was observed bilaterally. The accessorybellies were similar but not symmetrical. They were composed of two segments, one long and one short, onboth sides, and when observed together these appeared to form the letter X. The accessory fibers, on bothsides, originated from the anterior digastric muscle and inserted medially to the digastric fossa. Anatomicvariations of the digastric muscle may influence mastication and deglutition. Moreover, the accessory digastricmuscle affects diagnostic imaging and therapeutic procedures in head and neck surgery and must be consideredin procedures involving this area.
Subject(s)
Humans , Male , Adult , Deglutition/physiology , Mastication , Pharyngeal Muscles/anatomy & histology , Pharyngeal Muscles/physiopathology , Cadaver , DissectionABSTRACT
The study of lingual surfaces and the surface of interface epithelium-connective tissue of the tongue of Bradypus torquatus was performed by employing the light and scanning electron microscopy (SEM) techniques. The results revealed that the rostral part of the tongue presents a round apex and covered by filiform and fungiform lingual papillae and a ventral smooth surface. It was observed that the epithelial layer of the dorsal surface possesses the basal, spinosum, granular and cornified epithelial cells. The lamina propria is characterized by a dense connective tissue forming the long, short and round papillae. Numerous typical filiform papillae are located especially in the rostral part intermingled for few fungiform papillae, which were revealed in three-dimensional SEM images. Usually, the fungiform papillae are located in the border of rostral apex of the tongue exhibiting the rounded form. They are covered by keratinized epithelial cells. In the fungiform papillae, several taste pores were observed on the surface. The vallate papillae presented numerous taste buds in the wall of epithelial cells, being that the major number of taste buds is located on the superior half of vallate papilla. The taste pores are surrounded by several laminae of keratinized epithelial cells. The samples treated with NaOH solution and examined by SEM revealed, after removal of the epithelial layer, the dense connective core in original disposition, presenting different sizes and shapes. The specimens stained with Picrosirius and examined by polarized light microscopy revealed the connective tissue, indicating the collagen fibres type I and type III.
