Bone Exostosis: Difference between revisions

From Face, Mouth and Jaw
Jump to navigation Jump to search
Line 62: Line 62:
* '''Torus palatinus'''
* '''Torus palatinus'''
** Cross-sectional analysis of tori palatine demonstrate three layers:
** Cross-sectional analysis of tori palatine demonstrate three layers:
**# Nasal compact layer
**# ''Nasal compact layer'' - same thickness irrespective of size of tori ∴ confirming that development occurs by downward growth (nasal floor always remains flat)
**# Middle spongy layer - may not be seen in smaller tori
**# ''Middle spongy layer'' - may not be seen in smaller tori
**# Oral compact layer
**# ''Oral compact layer''
* '''Torus mandibularis'''
* '''Torus mandibularis'''
** Seen as lamellar periosteal outgrowth of the mandible
** Seen as lamellar periosteal outgrowth of the mandible

Revision as of 10:40, 15 January 2022

  • Nodular swellings of normal bone in the oral cavity
  • Also known as tori (torus = singular)
  • Common sites:
    • Hard palate (torus palatinus)
    • Lingual premolar region of the mandible (torus mandibularis)
    • Buccal alveolar bone of maxilla or mandible

Epidemiology

  • Incidence varies between different races[1]
    • More common in Inuit, Native American and Asian populations
  • Torus palatinus
    • More common than mandibular tori
    • Incidence - 9-66%
    • ♀ > ♂
  • Torus mandibularis
    • Incidence - 0.5-63.4%
    • ♂ > ♀

Clinical Features

  • Firm swellings with normal overlying mucosa
    • Whilst mucosa is normal it is usually thin and can have a blanched appearance (sometimes can ulcerate)
  • Small-sized lesions → <3mm elevation and <10mm diameter
  • Medium-sized lesions → 3-5mm elevation and 10-15mm diameter
  • Large-sized lesions → >5mm elevation and >15mm diameter
  • Usually only affects one site in an individual
  • Torus palatinus
    • Occurs in the midline of the palate (usually in the mid-third)
    • Usually symmetrical but if large can also become an irregular rounded mass
  • Torus mandibularis
    • Found on the lingual surface of the mandible
    • Usually adjacent to premolars and above the mylohyoid attachment
    • If very large can interfere with tongue movement
  • Other sites
    • Multiple bone exposes can also affect the buccal aspect of maxilla or mandible

Differential Diagnosis

  • Differential Diagnosis

Aetiology and Pathogenesis

Aetiology

  • Largely unknown
  • Some suggestions:
    • Hereditary (autosomal dominant inheritance has been described in some)
    • Masticatory hyperfunction

Investigations

Imaging

  • Radiographically tori appear as radiopaque masses
  • Dense bone ∴ they can obliterate details of the teeth and maxillary sinus in plain film radiographs
  • In large tori - the spongy layer in the middle appears less dense than the cortical bone

Histology

  • Torus palatinus
    • Cross-sectional analysis of tori palatine demonstrate three layers:
      1. Nasal compact layer - same thickness irrespective of size of tori ∴ confirming that development occurs by downward growth (nasal floor always remains flat)
      2. Middle spongy layer - may not be seen in smaller tori
      3. Oral compact layer
  • Torus mandibularis
    • Seen as lamellar periosteal outgrowth of the mandible

Management

  • Management

Prognosis and Complications

  • Prognosis and Complications

Follow-up

  • Follow-up

References

[[Category:]]