Introduction:
The teeth are highly essential for cutting and chewing food to aid in swallowing and digestion. They come in variable sizes and shapes and are named accordingly. Each tooth has its own action. These teeth’ roots are embedded in the upper and lower jaw and are covered by a soft tissue called gums or gingiva. The appearance of the tiny white teeth is what the parents of small babies eagerly wait for. It is an important milestone. But when that does not happen on time, that must definitely be concerning. This article discusses in detail the normal eruption period and patterns and causes for delayed teeth eruption.
How Many Teeth Are Present in Total?
Milk Teeth: There are 20 teeth present in the deciduous or primary dentition, that is, 10 in the upper jaw and 10 in the lower jaw.
Permanent Teeth: There are 32 teeth present in the permanent dentition, that is, 16 in the upper jaw and 16 in the lower jaw.
What Are the Types of Teeth?
Four types of teeth exist. They are,
Incisor - These are the front teeth located in the middle of the jaw. Humans have four central incisors (2 in the upper and 2 in the lower jaw) and four lateral incisors situated on either side of the central incisors in the upper and lower jaws. The incisors work to cut the food initially when we bite something.
Canine - There are four canines and are located next to the lateral incisor on both sides and in the upper and lower jaw. Their work is to tear the food, especially the meat.
Premolar - Similar to the incisors, premolars also are of two types. The first premolar is located next to the canine on both sides and in both jaws. The second premolar lies next to the first premolar on both sides and in both jaws. Hence, there are eight premolars in total—these help in crushing the food.
Molar - Molars have a flat table-like structure which helps in crushing the food into a paste. There are a total of 12 molars or grinding teeth in the oral cavity. Three molars are located in the backmost part of the upper and lower jaw on either side next to the second premolar. They are named first, second, and third molars, respectively. The third molar, or the wisdom tooth, is the most impacted tooth in a majority of the population and is the last tooth to erupt in the oral cavity.
The primary or deciduous dentition does not have all these four types of teeth. It consists of only the incisors, canines, and first and second molars.
Did You Know That a Child May Be Born With Teeth?
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Children may be born with teeth, or their teeth may erupt immediately after birth.
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Teeth present at the time of birth are called natal teeth.
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Teeth eruptions soon after birth (within one month after birth) are called neonatal teeth.
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It is advised to extract those teeth as the child might swallow or get choked.
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They may also cause irritation to the mother’s nipples during breastfeeding.
What Signs and Symptoms Occur During Milk Tooth Eruption?
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Lack of appetite.
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Itchy gums. The child will try to bite things with the gums.
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Drooling of saliva.
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Loose motions.
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The child may be irritated and will take everything into the mouth.
What Is the Eruption Sequence of Deciduous Dentition?
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Lower central incisors: 5-8 months of age.
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Upper central incisors: 6-10 months of age.
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Lower lateral incisors: 7-10 months of age.
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Upper lateral incisors: 8-12 months of age.
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Upper and lower first molars: 11-18 months of age.
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Upper and lower canines: 16-20 months of age.
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Upper and lower second molars: 20-30 months of age.
Primary teeth exfoliation leads to the eruption of permanent teeth. There are 32 permanent teeth in adults which replace the 20 primary teeth. The deciduous central incisors, lateral incisors, and canine are replaced by permanent central incisors, lateral incisors, and canine, respectively. The deciduous first molars and second molars are replaced by permanent first premolars and second premolars, respectively. In addition to these, permanent first, second and third molars also erupt.
What Is the Eruption Sequence of Permanent Dentition?
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Upper and lower first molars: 6-7 years of age.
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Lower central incisors: 6-7 years of age.
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Upper central incisors: 7-8 years of age.
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Lower lateral incisors: 7-8 years of age.
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Upper lateral incisors: 8-9 years of age.
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Lower canine: 9-10 years of age.
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Upper and lower first premolars: 10-12 years of age.
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Upper second premolars: 10-12 years of age.
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Lower second premolars: 11-12 years of age.
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Upper canine: 11-12 years of age.
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Lower second molars: 11-13 years of age.
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Upper second molars: 12-13 years of age.
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Upper and lower third molars: 17 years onwards.
The permanent teeth loss occurs due to periodontal disease, bone loss, pathological conditions, extraction of a grossly decayed tooth for orthodontic treatment, fractured tooth, etc.
Your child's milk teeth eruption should start by the age of 5-6 months. It is fine for milk teeth to erupt within 6 to 12 months of age. But by the time babies turn 11 months old, they usually have four teeth in their mouth.
What Conditions Cause Delayed Teeth Eruption?
Several reasons can cause your child’s teeth to erupt with a delay. They are,
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Nutritional Deficiency - If your baby lacks nutrition, there are possibilities for delayed tooth eruption.
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Genetic Disorders - The presence of genetic disorders such as Apert syndrome, Down syndrome, cleidocranial dysostosis, regional odontodysplasia, amelogenesis imperfecta, etc., can cause delayed tooth eruption. They can also cause several other tooth problems, such as defective teeth forms.
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Premature Baby or Low Birth Weight - These conditions can also lead to a delay in normal tooth eruption.
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Hormonal Disorders - If your baby has problems with thyroid or pituitary hormones, there are chances of delayed tooth eruption.
Conclusion:
In most conditions, delayed tooth eruption is not a concern if the eruption is delayed by only two to four months. But a delay in milk teeth eruption even after 12 months of age is a point to be concerned about. A pediatric dentist will be able to help assess the cause of delayed tooth eruption.
