Maxillary teeth are the teeth fixed within the maxilla, the bone forming the upper jaw and the structure of the middle face. They are fundamental components of the upper dental arch, designed to meet their counterparts in the lower jaw (mandible) to perform essential daily functions. The upper dental arch is semi-elliptical, providing a stable, fixed platform that supports the soft tissues of the face.
Classification and Structure
The sixteen permanent maxillary teeth are categorized into four distinct classes, each possessing a unique structure and specific role. Closest to the midline are the incisors (two central and two lateral), characterized by a single root and a sharp, chisel-like biting edge. Their slender design is optimized for shearing and cutting food.
Flanking the incisors are the canines, or cuspids, with a prominent, single, pointed cusp. These teeth have the longest roots, anchoring them firmly to withstand the forces required for tearing and piercing tough foods. Immediately behind the canines are the two premolars, or bicuspids, which are unique to the permanent set.
Maxillary premolars typically feature two cusps, giving them a dual function of tearing and crushing food. At the back of the arch are the molars, the largest teeth, which have broad, flat chewing surfaces with multiple cusps. Maxillary molars are supported by three separate roots, making them strong for the heavy grinding and crushing required during chewing.
Primary and Permanent Sets
Maxillary teeth develop in two sequential sets: primary and permanent. The initial set, or deciduous dentition, includes ten teeth in the upper arch. This set consists of four incisors, two canines, and four molars; premolars are absent.
Primary maxillary teeth begin to erupt around six months of age, with the full set generally present by two and a half years. These teeth maintain the space necessary for the eventual emergence of the permanent teeth beneath them. Primary molars are shed and replaced by the permanent premolars, which are new additions to the adult arch.
The permanent maxillary arch contains sixteen teeth: four incisors, two canines, four premolars, and six molars, including the third molars (wisdom teeth). This transition phase, known as mixed dentition, begins around age six when the first permanent molars erupt. The permanent set’s larger number and different composition are adapted to the increased size and functional demands of the mature jaw.
Essential Functions of the Upper Teeth
The primary function of the maxillary teeth is to work with the lower mandibular teeth to facilitate mastication (chewing food). The upper and lower arches must align precisely, a relationship termed occlusion, to ensure efficient mechanical breakdown of food. The anterior maxillary teeth (incisors and canines) are responsible for initial biting and tearing, while the posterior premolars and molars engage in crushing and grinding.
Maxillary teeth also contribute significantly to clear speech, or phonation. Their position helps shape the airflow and guides the tongue to produce specific sounds, such as “s” and “t.” Their presence provides a necessary barrier and reference point for the tongue to articulate various consonants.
Furthermore, the maxillary teeth play a role in maintaining the structure and aesthetics of the face. They provide direct support for the lips and cheeks, preventing them from collapsing inward and helping to create a balanced facial profile. The proper alignment and presence of these teeth are important for guiding the lower jaw into a stable resting position.