Wisdom teeth, also known as third molars, are the final set of adult teeth to emerge. Positioned at the very back of the upper and lower jaws, these teeth typically begin to appear during late adolescence or early adulthood. They are called wisdom teeth because they erupt at an age when individuals are considered “wiser” than when their other permanent teeth emerge. Most adults have four wisdom teeth, though some individuals may have fewer or none at all.
The Timeline of Wisdom Teeth Development
The journey of wisdom teeth development is a lengthy process that begins many years before they become visible in the mouth. The initial formation of a wisdom tooth starts as a tiny tooth bud, which can be detected as early as 6 to 10 years of age. This early development occurs deep within the jawbone, invisible to the naked eye.
Following the initial bud formation, the crown of the wisdom tooth begins to develop, a stage that typically occurs between 12 and 16 years old. After the crown fully forms, the roots of the tooth start to grow. The actual eruption, where the tooth breaks through the gums and becomes visible, commonly takes place between the ages of 17 and 25 years. While the visible emergence might seem relatively quick, the entire developmental process, from bud formation to full eruption, spans over a decade.
Factors Affecting Wisdom Teeth Eruption
The timing and success of wisdom teeth eruption can vary among individuals due to several influencing factors. Genetics play a role, as family history can indicate whether wisdom teeth will develop and how they might erupt. Inherited jaw size and shape are influential; individuals with smaller jaws may not have sufficient space for these molars to emerge properly.
The physical space available in the mouth is a determinant for eruption. If there is not enough room, the wisdom teeth may grow at an angle or become blocked by adjacent teeth. The angle at which the developing tooth is positioned within the jaw can also affect its ability to erupt fully. The presence and position of other teeth in the dental arch can create obstacles, hindering the eruption path of the third molars.
Understanding Impacted Wisdom Teeth
When a wisdom tooth does not fully emerge into its proper position, it is referred to as an impacted wisdom tooth. This occurs because the tooth is blocked by another tooth, the jawbone, or overlying soft tissue. Impaction is a common outcome, especially when there is insufficient space in the mouth for the tooth to grow normally.
Impacted wisdom teeth are categorized based on their position and the surrounding structures. A soft tissue impaction means the tooth has penetrated the bone but remains covered by gum tissue. A bony impaction indicates the tooth is mostly or entirely encased within the jawbone.
Impactions are also classified by the angle of the tooth. A mesial impaction involves the tooth tilting forward towards the front of the mouth. A distal impaction occurs when the tooth angles towards the back of the mouth. Vertical impaction describes a tooth that is oriented correctly but is unable to break through the bone or gums. A horizontal impaction is characterized by the tooth lying completely sideways, parallel to the jawbone, often pressing against the adjacent molar.