Mental spine

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Mental spine
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The posterior aspect of the mandible, showing mental spines.
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A medial view of the mandible showing the attachments of genmkyoid and genioglossus.
Details
Part of Mandible
System Skeletal
Identifiers
Latin spinae mentalis
Anatomical terminology

A mental spine is a small projection of bone on the posterior aspect of the mandible in the midline. There are usually four mental spines: two superior and two inferior. Collectively they are also known as the genial tubercle, [1] genial apophysis and the Latin name spinae mentalis. The inferior mental spines are the points of origin of the geniohyoid muscle, [2] one of the suprahyoid muscles, and the superior mental spines are the origin of the genioglossus muscle, one of the muscles of the tongue. Mental spines are important landmarks in clinical practice.

Contents

Structure

Mental spines are found on the posterior aspect of the mandible (lower jaw bone) in the midline. [3] They usually surround spinous mental foramina in the midline. [3]

Variation

Mental spines may be found in over 98% of people. [3] Over 70% of mandibles may only have 2 superior spines, while around 20% may have 4 spines. [3]

Function

The inferior mental spines are the points of origin of the geniohyoid muscle, [2] one of the suprahyoid muscles, and the superior mental spines are the origin of the genioglossus muscle, one of the muscles of the tongue.

Clinical significance

Mental spines are important landmarks for maxillofacial surgeons, dentists, and radiologists. [3]

Etymology

The adjective mental in this instance is used in its "chin-related" sense (from Latin mentum) rather than its more common "mind-related" sense (from Latin mens). Collectively they are also known as the genial tubercle, [1] genial apophysis and the Latin name spinae mentalis.

Additional images

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References

  1. 1 2 "Genial tubercle." The American Heritage Stedman's Medical Dictionary. Houghton Mifflin Company, 2002. Accessed: 22 Oct. 2007.
  2. 1 2 "Genial tubercle." Mosby's Dental Dictionary. Elsevier, Inc., 2004. Accessed: 22 Oct. 2007.
  3. 1 2 3 4 5 Singh, V.; Anand, M. K.; Dinesh, K. (2000-12-01). "Variations in the pattern of mental spines and spinous mental foramina in dry adult human mandibles". Surgical and Radiologic Anatomy. 22 (3). Springer Publishing: 169–173. doi:10.1007/s00276-000-0169-1. ISSN   1279-8517. PMID   11143309. S2CID   8362848 via Springer.