Maxillary canine tooth growth in Babirusa (genus Babyrousa)
Babirusa (genus Babyrousa), wild pigs from the Indonesian island of Sulawesi and neighbouring small islands, most obviously differ from other wild pigs in that the maxillary (upper) canine teeth of the males pierce through the skin of the nose and curl over the forehead. The females sometimes show small teeth piercing through the nasal skin. The process of anatomical growth of these maxillary canine teeth and the remodelling of the alveolar processes (tooth sockets) within which they grow is here illustrated and explained for the first time. Forty-four skulls in museum and private collections were studied. They represented all ages, from neonates to adult animals. The deciduous maxillary canine teeth of both sexes begin life by pointing rostrally and slightly ventrally into the oral cavity and then appear to be rotated dorsally and medially. The permanent teeth continue this process, rotating through approximately 90 degrees, from pointing rostrally to pointing dorsally through the nasal skin. The structure of the alveolar process is in the meantime modified and develops a bony flange caudally. We hypothesise that some form of connective tissue, stretching from the flange to the subcutaneous tissues of the forehead, exerts a caudally orientated pulling force that results in the gradual rotation of the alveolar process. The contributory role in this pulling force of bone growth at the facial sutures is also highlighted.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).