The sella point is displaced backward and downward during growth and development. Data on the size of the sella turcica have been well-reported in the literature. The size of sella turcica assessed from radiographs can be either linear or various methods of area and volume measurements. It typically ranges from 4 to 12 mm for the vertical and from 5 to 16 mm for the anteroposterior dimension.
Any change in the size of the sella turcica is more frequently related to pathology, enlargement is the most frequent finding but is usually not accompanied by bone erosion. A microsurgical anatomical study on sphenoidal blocks from cadavers of different ages was performed by Quakinine and Hardy and found that the average transverse width of sella turcica was 12 mm, length was 8 mm, and the average height was 6 mm.
Axelsson et al. The depth and diameter in males and females were similar but the length was larger in males. Alkofide[ 1 ] studied the lateral cephalograms of Saudi subjects with an age range of years with different skeletal types. Linear dimensions of length, depth, and diameter of sella turcica was measured [ Figure 1 ]. It was found that there were no statistically significant differences between males and females in all the three linear dimensions.
When linear dimensions were compared with age, the size of sella turcica was larger in older age group than in the younger age group. According to Preston,[ 12 ] pituitary fossa increased in size with age and found a positive correlation of the area of the sella to age. After 26 years of age, no significant increase was observed on the size. Elster et al. Pituitary gland was mm in females while in males it was 7 mm, both being larger than in childhood or young adult hood.
They also concluded that young adults had slightly but significantly smaller glands than adolescents of the same gender. The dimensional changes in the sella turcica had a significant positive linear trend to length, depth, and diameter until 25 years of age.
After 26 years of age, no significant increase was found in sella turcica dimensions. The most common causes of enlargement of sella turcica are the presence of intrasellar adenomas e. Morphological appearance of sella turcica is established in early embryonic structure.
Variations in the shape of sella urcica have long been reported by many researchers. The shape of sella turcica was classified in to circular, oval, and flattened or saucer-shaped and majority of the subjects had either a circular or oval shaped sella.
Other classifications were based on the contours of the sella floor, the angles formed by the contours of anterior and posterior clinoid processes and tuberculum sellae and the fusion of both clinoid processes as sella turcica bridge. He concluded that sella turcica bridge was evident as early as 6 years of age. Different morphological types of sella turcica: a Normal sella turcica, b oblique anterior wall, c double contour of the floor, d irregularity notching in the posterior part of sella turcica, e sella turcica bridge, f pyramidal shape of dorsum sellae.
Literature indicates the occurrence of sella turcica bridge as a radiographic feature in basal cell carcinoma, Reigers syndrome. Kjaer et al. Meyer-Marcotty et al. They concluded that these abnormal features could be primary indicators for diagnosis of Axenfeld-Rieger syndrome. Variations in the shape of sella turcica can be misleading since it may be present in normal subjects and in medically compromised conditions such as in spina bifida.
Anatomical and radiographic studies showed that the occurrence of sella turcica bridging ranges from 5. Jones et al. When different skeletal classes were analyzed for bridging, Abdel Kaber studied the prevalence of a sella turcica bridge in relation to the three skeletal classes in Saudi subjects and found a higher percentage of sella turcica bridges in orthognathic-surgical patients with a skeletal class III malocclusion Marsan and Oztas[ 32 ] studied the incidence of bridging in 61 skeletal class III Turkish adult females and compared with 57 skeletal class I females.
Irregularity in the dorsum sella was found in He concluded that bridging occurs more frequently in subjects with craniofacial deviations compared to normal subjects. Intracranial calcifications occurring in subjects with various dental anomalies are highly suggestive of a genetic etiology underlying both these conditions. Leonardi et al. Complete calcification of interclinoid ligament was present in Partial calcification of the interclinoid ligament was seen in They concluded that early appearance of sella turcica bridges during development should alert the clinicians to possible tooth anomalies in life later.
An association between sella turcica bridging and dental transposition was also studied by Leonardi et al. The linear dimensions of sella turcica can be used to approximate the pituitary gland size. The orthodontist should be familiar with different morphologies of the sella turcica to differentiate normal from abnormal appearance. Lateral cephalograms can be suggested for children, if there is a family history of impacted teeth, signs of ectopic eruption, and other dental anomalies so that treatment can be diagnosed and treated early.
Source of Support: Nil. Conflict of Interest: None declared. National Center for Biotechnology Information , U. Dent Res J Isfahan. Author information Article notes Copyright and License information Disclaimer. Address for correspondence: Dr. E-mail: ni. Received Mar; Accepted May. This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3.
This article has been cited by other articles in PMC. Abstract The sella turcica is a structure which can be readily seen on lateral cephalometric radiographs and sella point is routinely traced for various cephalometric analyses. Keywords: Morphology, sella point, sella turcica, size.
Open in a separate window. Figure 1. Figure 2. Footnotes Source of Support: Nil. Alkofide EA. Eur J Orthod. Post-natal size and morphology of the sella turcica. Longitudinal cephalometric standards for Norwegians between 6 and 21 years of age. Miletich I, Sharpe PT. Neural crest contribution to mammalian tooth formation. In vitro differentiation of dental epithelial progenitor cells through epithelial-mesenchymal interactions. Arch Oral Biol. Kjaer I, Fischer-Hansen B.
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The volume of the sella turcica in children: New standards. The study of shape and size of normal sella turcica in cephalometric radiographs. Korean J Oral Maxillofac Radiol. Quaknine GE, Hardy J. Microsurgical anatomy of the pituitary gland and the sellar region. Become a Gold Supporter and see no ads. Log in Sign up. Articles Cases Courses Quiz. About Recent Edits Go ad-free.
Edit article. View revision history Report problem with Article. Citation, DOI and article data. Pituitary fossa. Reference article, Radiopaedia. Central Nervous System. URL of Article. On this page:. Quiz questions. The pituitary fossa: a correlative anatomic and MR study. Chaudhary V, Bano S. Imaging of the pituitary: Recent advances. Indian J Endocrinol Metab.
Diagnosis and management of pituitary tumors. Humana Press. Read it at Google Books - Find it at Amazon 4. Microanatomy of the hypophyseal fossa boundaries. Journal of neurosurgery. Microsurgical anatomy of the lateral walls of the pituitary fossa. Acta neurochirurgica. The medial wall of the cavernous sinus: microsurgical anatomy.
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