Definition and Structure of Dental Arches
- Dental arches are crescent arrangements of teeth on each jaw.
- The superior dental arch (maxillary) is larger than the inferior dental arch (mandibular).
- The occlusion determines the occlusal relationship of opposing teeth.
- Malocclusion can occur due to facial or dental development issues.
- The upper and lower teeth do not perfectly correspond when the mouth is closed.
Importance of Dental Arch Size
- The size of the dental arch determines the positioning of teeth.
- A small arch can lead to overlapping and improperly positioned teeth.
- Improperly positioned teeth can cause gum problems or infections.
- The arch can expand as a child grows, allowing for proper tooth positioning.
- Dentists use fixed or removable prostheses to replace missing or damaged teeth.
Short Dental Arch as a Treatment Option
- The short dental arch (SDA) is a defined treatment option for partially dentate patients.
- Restoring the complete dental arch may not always be necessary.
- The SDA provides an affordable and functional treatment option.
- Individualised treatment plans are needed to meet patients' needs.
- The length of the occlusal table is a fundamental question in any treatment plan.
Hemiarch and Quadrants
- A hemiarch refers to the right or left half of an arch.
- It corresponds to one of the four quadrants.
- Each quadrant contains a specific set of teeth.
- Understanding the division of the arch into quadrants helps in dental treatment planning.
- The concept of hemiarch is relevant in dental terminology.
References
- This article incorporates text from the 20th edition of Gray's Anatomy (1918).
- Debora Armellini, DDS, MS, and J. Anthony von Fraunhofer wrote a review of the literature on the shortened dental arch, published in The Journal of Prosthetic Dentistry.
- The article is available in the public domain.
- The Wikipedia page on dental arch provides additional information and links to related topics.
The dental arches are the two arches (crescent arrangements) of teeth, one on each jaw, that together constitute the dentition. In humans and many other species, the superior (maxillary or upper) dental arch is a little larger than the inferior (mandibular or lower) arch, so that in the normal condition the teeth in the maxilla (upper jaw) slightly overlap those of the mandible (lower jaw) both in front and at the sides. The way that the jaws, and thus the dental arches, approach each other when the mouth closes, which is called the occlusion, determines the occlusal relationship of opposing teeth, and it is subject to malocclusion (such as crossbite) if facial or dental development was imperfect.
| Dental arch | |
|---|---|
 Permanent teeth of upper dental arch, seen from below. | |
 Permanent teeth of right half of lower dental arch, seen from above. | |
| Details | |
| Identifiers | |
| Latin | arcus dentalis mandibularis, arcus dentalis maxillaris |
| MeSH | D003724 |
| Anatomical terminology | |
Because the upper central incisors are wider than the lower ones, the other teeth in the upper arch are arrayed somewhat distally, and the two sets do not quite correspond to each other when the mouth is closed: thus the upper canine tooth rests partly on the lower canine and partly on the lower first premolar, and the cusps of the upper molar teeth lie behind the corresponding cusps of the lower molar teeth.
The two series, however, end at nearly the same point behind; this is mainly because the molars in the upper arch are the smaller.
Since there are a standard number of teeth in humans, the size of the dental arch is of vital importance in determining how the teeth are positioned when they appear. While the arch can expand as a child grows, a small arch will force the teeth to grow close together. This can result in overlapping and improperly positioned teeth. Teeth may tilt at an awkward angle, putting pressure on gums when food is being chewed. This can ultimately lead to compromised gums or infections.
Dentists replace missing, damaged, and severely decayed teeth by fixed or removable prostheses to restore or improve mastication function. There is a fundamental question in any treatment plan, namely, the desirable/mandatory length of an occlusal table.
There have been various references in the literature to the concept of the short dental arch (SDA) as a defined treatment option for the partially dentate patient. While many dentists may accept that restoring the complete dental arch is not always necessary, there still is the need to provide the patient with an affordable and functional treatment, a need satisfied by the short dental arch.
A hemiarch (hemi- + arch) is the right or left half of an arch. It corresponds to 1 of the 4 quadrants.
