title: Computational fluid dynamics analysis of salivary flow and its effect on sialolithogenesis.
abstract: OBJECTIVE
  Sialolithiasis is a common disease caused by intraductal stones, formed by reduction in salivary flow, salivary stagnation, and metabolic events. We used computational fluid dynamics to investigate changes in salivary flow field around parotid stones of different shapes.
  
  
  METHODS
  Three-dimensional configurations of the Stensen's duct were reconstructed from computed tomography sialographic images. Fluid dynamics modeling was used to analyze the salivary flow field around stones under unstimulated and stimulated conditions.
  
  
  RESULTS
  The majority of sialoliths were oval-shaped (59/98), followed by irregular (24/98) and round (15/98). Salivary velocity was significantly higher around streamlined stones, compared with round (P = 0.013) and oval (P = 0.025) types. Changes in salivary flow field around sialoliths were found to affect the pattern of mineral deposition in saliva. The area of low velocity around the round stone was double the size observed around the streamlined stone during the unstimulated state, whereas in the stimulated state, local vortexes were formed on the downstream side of round and oval stones.
  
  
  CONCLUSIONS
  Salivary flow field around sialoliths plays an important role in the progression of multicentric stones, and analysis of the salivary dynamics during sialolithiasis may provide deeper understandings of the condition and aid in developing successful treatment strategies.
authors.affiliation: Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, Guangdong, China.
authors.forename: P
authors.initials: P
authors.lastname: Zhu
authors.forename: Y
authors.initials: Y
authors.lastname: Lin
authors.forename: H
authors.initials: H
authors.lastname: Lin
authors.forename: Y
authors.initials: Y
authors.lastname: Xu
authors.forename: Qy
authors.initials: Q
authors.lastname: Zheng
authors.forename: Y
authors.initials: Y
authors.lastname: Han
mesh_terms: D000328:Adult; D000368:Aged; D003198:Computer Simulation; D005260:Female; D006801:Humans; D057446:Hydrodynamics; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012463:Saliva; D012465:Salivary Duct Calculi / Q000000981:diagnostic imaging / Q000209:etiology*; D012796:Sialography; D014057:Tomography, X-Ray Computed
keywords: computational fluid dynamics; flow field; lithogenesis; saliva; sialoliths