Deciduous teeth, otherwise known as baby teeth, temporary teeth, milk teeth, and now more commonly primary teeth, are the first set of teeth in the growth development of humans and other diphyodont (two sets of teeth) mammals. The word deciduous has come from the Latin word which means to fall off or shed like leaves of a tree. The other terms unfortunately denote a lack of importance because the nick names indicate the usefulness of these teeth for a short period only. They develop during the embryonic stage of development and erupt—that is, they become visible in the mouth—during infancy. They are usually lost and replaced by permanent teeth, but in the absence of permanent replacements, they can remain functional for many years.
Primary teeth start to form during the embryo phase of pregnancy. The development of primary teeth starts at the sixth week of tooth development as the dental lamina. This process starts at the midline and then spreads back into the posterior region. By the time the embryo is eight weeks old, there are ten buds on the upper and lower arches that will eventually become the primary (deciduous) dentition. These teeth will continue to form until they erupt in the mouth. In the primary dentition there are a total of twenty teeth: five per quadrant and ten per arch. The eruption of these teeth ("teething") begins at the age of six months and continues until twenty-five to thirty-three months of age during the primary dentition period. Usually, the first teeth seen in the mouth are the mandibular centrals and the last are the maxillary second molars.
The primary dentition is made up of central incisors, lateral incisors, canines, first molars, and secondary molars; there is one in each quadrant, making a total of four of each tooth. All of these are gradually replaced with a permanent counterpart except for the primary first and second molars; they are replaced by premolars. The replacement of primary teeth begins around age six, when the permanent teeth start to appear in the mouth, resulting in mixed dentition. The erupting permanent teeth cause root resorption, where the permanent teeth push on the roots of the primary teeth, causing the roots to be dissolved by odontoclasts (as well as surrounding alveolar bone by osteoclasts) and become absorbed by the forming permanent teeth. The process of shedding primary teeth and their replacement by permanent teeth is called exfoliation. This may last from age six to age twelve. By age twelve there usually are only permanent teeth remaining.
Primary teeth are essential in the development of the oral cavity. The primary teeth maintain the arch length within the jaw, the bone and the permanent teeth replacements develop from the same tooth germs as the primary teeth. The primary teeth provide guides for the eruption pathway of the permanent teeth. Also the muscles of the jaw and the formation of the jaw bones depend on the primary teeth to maintain proper spacing for permanent teeth. The roots of primary teeth provide an opening for the permanent teeth to erupt. The primary teeth are important for the development of the child's speech, for the child's smile and play a role in chewing of food.
Important QUESTIONS for Objective Type Exams:
Q: A condition where two sets of teeth erupt is called?
Ans: Dipyodonty
Q: A condition where teeth are replaced throughout the life is called?
Ans: Polyphyodonty
Q: How many primary teeth are present in oral cavity?
Ans: 20 teeth (4 quadrants, each quadrant consisting of 1 central incisor, 1 lateral incisor, 1 canine, 1 first molar and 1 2nd molar).
Q: Which set of teeth appear first in the oral cavity?
Ans: Primary or Deciduous or Milk or Baby teeth.
Q: When primary teeth start to form?
Ans: Between sixth and eighth week of prenatal development.
Q: The phenomenon of eruption of primary teeth in the oral cavity is called?
Ans: Teething
Q: At what age, the eruption of the primary teeth begins in the oral cavity?
Ans: 6 - 7 months or 7 - 8 months
Q: At what age, the eruption of all the primary teeth ends?
Ans: 2 ½ to 3 ½ years
Q: Which teeth erupts first in the oral cavity?
(OR)
Which primary teeth erupts first in the oral cavity?
Ans: Deciduous / Mandibular central incisors
Q: Which primary teeth erupt last erupt in the oral cavity?
Ans: Maxillary second molars.
Q: Which set of teeth is absent in primary dentition?
Ans: Premolars
Q: At what age, the replacement of primary teeth begins?
Ans: 6 years of age
Q: The process of shedding primary teeth and their replacement by permanent teeth is called?
Ans: Exfoliation
Q: At what age, all the primary teeth are replaced by the permanent teeth in the oral cavity?
Ans: 12-13 years.
Q: The period when only primary teeth are present in the oral cavity is called?
Ans: Primary Dentition Period
Q: When does the roots of the deciduous teeth begin to resorb?
Ans: 2 - 3 years after their completion.
Q: Exfoliation of the deciduous teeth occurs between?
Ans: 7 to 12 years.
Q:
Primary teeth start to form during the embryo phase of pregnancy. The development of primary teeth starts at the sixth week of tooth development as the dental lamina. This process starts at the midline and then spreads back into the posterior region. By the time the embryo is eight weeks old, there are ten buds on the upper and lower arches that will eventually become the primary (deciduous) dentition. These teeth will continue to form until they erupt in the mouth. In the primary dentition there are a total of twenty teeth: five per quadrant and ten per arch. The eruption of these teeth ("teething") begins at the age of six months and continues until twenty-five to thirty-three months of age during the primary dentition period. Usually, the first teeth seen in the mouth are the mandibular centrals and the last are the maxillary second molars.
The primary dentition is made up of central incisors, lateral incisors, canines, first molars, and secondary molars; there is one in each quadrant, making a total of four of each tooth. All of these are gradually replaced with a permanent counterpart except for the primary first and second molars; they are replaced by premolars. The replacement of primary teeth begins around age six, when the permanent teeth start to appear in the mouth, resulting in mixed dentition. The erupting permanent teeth cause root resorption, where the permanent teeth push on the roots of the primary teeth, causing the roots to be dissolved by odontoclasts (as well as surrounding alveolar bone by osteoclasts) and become absorbed by the forming permanent teeth. The process of shedding primary teeth and their replacement by permanent teeth is called exfoliation. This may last from age six to age twelve. By age twelve there usually are only permanent teeth remaining.
Primary teeth are essential in the development of the oral cavity. The primary teeth maintain the arch length within the jaw, the bone and the permanent teeth replacements develop from the same tooth germs as the primary teeth. The primary teeth provide guides for the eruption pathway of the permanent teeth. Also the muscles of the jaw and the formation of the jaw bones depend on the primary teeth to maintain proper spacing for permanent teeth. The roots of primary teeth provide an opening for the permanent teeth to erupt. The primary teeth are important for the development of the child's speech, for the child's smile and play a role in chewing of food.
Important QUESTIONS for Objective Type Exams:
Q: A condition where two sets of teeth erupt is called?
Ans: Dipyodonty
Q: A condition where teeth are replaced throughout the life is called?
Ans: Polyphyodonty
Q: How many primary teeth are present in oral cavity?
Ans: 20 teeth (4 quadrants, each quadrant consisting of 1 central incisor, 1 lateral incisor, 1 canine, 1 first molar and 1 2nd molar).
Q: Which set of teeth appear first in the oral cavity?
Ans: Primary or Deciduous or Milk or Baby teeth.
Q: When primary teeth start to form?
Ans: Between sixth and eighth week of prenatal development.
Q: The phenomenon of eruption of primary teeth in the oral cavity is called?
Ans: Teething
Q: At what age, the eruption of the primary teeth begins in the oral cavity?
Ans: 6 - 7 months or 7 - 8 months
Q: At what age, the eruption of all the primary teeth ends?
Ans: 2 ½ to 3 ½ years
Q: Which teeth erupts first in the oral cavity?
(OR)
Which primary teeth erupts first in the oral cavity?
Ans: Deciduous / Mandibular central incisors
Q: Which primary teeth erupt last erupt in the oral cavity?
Ans: Maxillary second molars.
Q: Which set of teeth is absent in primary dentition?
Ans: Premolars
Q: At what age, the replacement of primary teeth begins?
Ans: 6 years of age
Q: The process of shedding primary teeth and their replacement by permanent teeth is called?
Ans: Exfoliation
Q: At what age, all the primary teeth are replaced by the permanent teeth in the oral cavity?
Ans: 12-13 years.
Q: The period when only primary teeth are present in the oral cavity is called?
Ans: Primary Dentition Period
Q: When does the roots of the deciduous teeth begin to resorb?
Ans: 2 - 3 years after their completion.
Q: Exfoliation of the deciduous teeth occurs between?
Ans: 7 to 12 years.
Q:
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