Tag: role of receptors in the mouth

In anatomy, a heterodont is an animal which possesses more than a single tooth morphology. For example, members of the Synapsida generally possess incisors, canine, premolars, and molars. The presence of heterodont dentition is evidence of some degree of feeding/hunting specialization in a species. In contrast, homodont dentition refers to a set of teeth that possess the same tooth morphology. Acrodont is a formation of the teeth whereby the teeth are consolidated with the summit of the alveolar ridge of the jaw without sockets. Pleurodont is a formation of the teeth that are fused by their sides to the inner surface of the jaw bones. Thus, option D is correct.

The permanent molars occupy the most posterior portion of the dental arch. They have the largest occlusal surfaces of any of the teeth and have from three to five major cusps. Lower permanent molars always have two lingual cusps and upper permanent molars always have two buccal cusps. Lower molars have two roots and upper molars have three roots. Molar teeth by definition are cheek teeth that are not preceded by primary teeth. Permanent molars are accessional teeth without primary predecessors. In contrast to the molars, permanent incisors, canines and premolars are succedaneous (successional teeth). Premolar, canine and incisors does not have three roots. Thus, option A is correct.

A wisdom tooth or third molar is one of the three molars per quadrant of the human dentition. It is the most posterior of the three. Wisdom teeth generally erupt between the ages of 17 and 25. Most adults have four wisdom teeth (a third molar in each of the four quadrants), but it is possible to have fewer or more, in which case the extras are called supernumerary teeth. Wisdom teeth commonly affect other teeth as they develop, becoming impacted or "coming in sideways". They are often extracted when this occurs. 

Entamoeba gingivalis is a protozoan endoparasite, residing in the tartar and pus pockets of teeth of pyorrhoea infected human beings. It is the first parasitic amoeba known to human beings. 

The skeletal system is divided into an axial and appendicular skeleton and it provides both support protection to the brain as well as give shape to the face. The skull is part of the axial skeleton. Skull or cranium has 22 bones out which mandible  (lower jaw) is a single bone. It is lowest and strongest bone which hold the lower teeth in the socket and gives shape to the face. 

Hardest substance of the body is enamel. It is the thin outer covering of the tooth. It is composed of hydroxyapatite, which is a crystalline calcium phosphate. The color can vary from light yellow to a grayish white. It protects the tooth.

There are several types of teeth and each performs its own special function in the chewing process, depending on its size, shape, location within the jaws. Starting at the midline, the permanent dentition is comprised of incisors, canines, premolars and molars.
Therefore, the correct answer is option D.

Teeth are the hardest substance in the human body. The enamel on your teeth is the hardest and most highly mineralized substance in your body. It covers the outer layer of each tooth and it is the most visible part of the tooth. The enamel is made up mostly of minerals, primarily hydroxyapatite. So, enamel is the hardest substance in our body compared to dentine, collagen and melanin. 

Dental pulp is an unmineralized oral tissue composed of soft connective tissue, vascular, lymphatic and nervous elements that occupies the central pulp cavity of each tooth. Pulp has a soft, gelatinous consistency. The pulp cavity extends down through the root of the tooth as the root canal which opens into the periodontium via the apical foramen. The blood vessels, nerves etc. of dental pulp enter and leave the tooth through this foramen. This sets up a form of communication between the pulp and surrounding tissue - clinically important in the spread of inflammation from the pulp out into the surrounding periodontium.