The groups of fibers are named alveolar crest, horizontal, oblique, periapical, and interradicular fibers.

Horizontal fibers(J): attach to the cementum apical to the alveolar crest fibers and run perpendicularly from the root of the tooth to the alveolar bone.

Alveolar crest fibers (I): extend obliquely from the cementum just beneath the junctional epithelium to the alveolar crest.

It is thought that the periodontal ligament may respond to increased occlusal (biting) forces by resorbing some of the bone of the alveolar crest, which may result in increased tooth mobility, however these changes are reversible if the occlusal force is reduced.

Despite the difficulty in finding common, comparable landmarks between normal soft palates and cleft palates, analytical methods have been done to assess differences in degree of curvature of the alveolar crest, 2-dimmensional and 3-dimmensional surface area, and slope of the alveolar crest.