Academic literature on the topic 'Primary maxillary incisors'

Dental trauma in childhood and adolescence is common. At 5 years of age 31–40% of boys and 16–30% of girls, and at 12 years of age 12–33% of boys and 4–19% of girls, will have suffered some dental trauma. Boys are affected almost twice as often as girls in both the primary and the permanent dentitions. The majority of dental injuries in the primary and permanent dentitions involve the anterior teeth, especially the maxillary central incisors. Concussion, subluxation, and luxation are the most common injuries in the primary dentition, while uncomplicated crown fractures are most common in the permanent dentition. Prognosis of traumatic injuries has improved significantly in the last 20 years. This has been largely due to a greater understanding of dental pulp reaction patterns and vital pulp therapies. Children are most accident prone between 2 and 4 years for the primary dentition and between 7 and 10 years for the permanent dentition. Coordination and judgement are incompletely developed in children during the primary dentition years, and the majority of injuries are due to falls in and around the home as the child becomes more adventurous and explores his/her surroundings. Most injuries in the permanent dentition are caused by falls and collisions while playing and running, although bicycles are a common accessory. The place of injury varies in different countries according to local customs, but accidents in the school playground remain common. Sports injuries usually occur in the teenage years and are commonly associated with contact sports. Injuries due to road traffic accidents and assaults are most commonly associated with the late teenage years and adulthood, and are often closely related to alcohol abuse. One form of injury in childhood that must never be forgotten is child physical abuse or non-accidental injury (NAI). More than 50% of these children will have orofacial injuries (see also Chapter 4, Safeguarding Children). Accidental dental injuries can result from direct or indirect trauma. Direct trauma occurs when a tooth receives a direct blow, making this sort of injury more common at the front of the mouth.

A wide variety of processes can affect the formation of teeth during development. The number, size, shape, and quality of dental hard tis­sue may be abnormal and teeth may erupt early or be prematurely shed or resorbed. When a child presents with a tooth abnormality, the clin­ical and radiographic features are often distinctive and management depends on diagnosis (Box 5.1). Broadly, developmental abnormal­ities of the teeth can be either genetically determined or acquired as a result of injurious processes affecting the developing teeth. It can be problematic to make a diagnosis, particularly when teeth initially erupt. Sometimes pathological examination of a shed or extracted tooth by ground sectioning (for enamel) or conventional sectioning of a decalci­fied tooth can provide a diagnosis. Research has provided insights into the genetic and structural basis of dental anomalies, and has resulted in a complex and extensive classification of subtypes. Minor abnormal­ities, such as failure of development of a few teeth or enamel erosion in adult life, may be dealt with in general dental practice, but it is advisable to refer younger patients with more complex or extensive dental abnor­malities to a specialist in child dental health, with links to expert diag­nostic facilities and input from orthodontic and restorative colleagues. The publically available Online Mendelian Inheritance in Man (OMIM) database provides an invaluable resource for genetic disorders, including dental abnormalities. Supernumerary teeth are common and may be rudimentary in form or of normal morphology, when they are referred to as supplemental teeth. The most common supernumerary tooth occurs in the mid- line of the maxillary alveolus and is referred to as a mesiodens, which usually has a conical shape. Eruption of adjacent normal successor teeth may be impeded by a mesiodens, which is an indication for its removal. Most supernumerary teeth occur as a sporadic event in devel­opment, but multiple extra teeth can be found in certain developmen­tal disorders. Failure of development of tooth germs results in teeth missing from the dental arch and is referred to as hypodontia. Most often the missing teeth are third molars, second premolars, and upper lateral incisors. Hypodontia is more common in the permanent dentition than in the primary teeth.