Skip to main content Accessibility help

Mineralization of Sialoliths Investigated by Ex Vivo and In Vivo X-ray Computed Tomography

  • Pedro Nolasco (a1) (a2), Paulo V. Coelho (a3) (a4), Carla Coelho (a3), David F. Angelo (a4), J. R. Dias (a5), Nuno M. Alves (a5), António Maurício (a6), Manuel F.C. Pereira (a6), António P. Alves de Matos (a7), Raul C. Martins (a2) and Patrícia A. Carvalho (a1) (a8)...


The fraction of organic matter present affects the fragmentation behavior of sialoliths; thus, pretherapeutic information on the degree of mineralization is relevant for a correct selection of lithotripsy procedures. This work proposes a methodology for in vivo characterization of salivary calculi in the pretherapeutic context. Sialoliths were characterized in detail by X-ray computed microtomography (μCT) in combination with atomic emission spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Correlative analysis of the same specimens was performed by in vivo and ex vivo helical computed tomography (HCT) and ex vivo μCT. The mineral matter in the sialoliths consisted essentially of apatite (89 vol%) and whitlockite (11 vol%) with average density of 1.8 g/cm3. In hydrated conditions, the mineral mass prevailed with 53 ± 13 wt%, whereas the organic matter, with a density of 1.2 g/cm3, occupied 65 ± 10% of the sialoliths’ volume. A quantitative relation between sialoliths mineral density and X-ray attenuation is proposed for both HCT and μCT.


Corresponding author

*Author for correspondence: Pedro Nolasco, E-mail:


Hide All
Alves de Matos, AP, Carvalho, PA, Almeida, A, Duarte, L, Vilar, R & Leitao, J (2007). On the structural diversity of sialoliths. Microsc Microanal 13, 390396.
Bazin, D, Daudon, M, Combes, C & Rey, C (2012). Characterization and some physicochemical aspects of pathological microcalcifications. Chem Rev 112, 50925120.
Blumenthal, NC, Betts, F & Posner, AS (1981). Formation and structure of Ca-deficient hydroxyapatite. Calcif Tissue Int 33, 111117.
Boskey, AL, Boyan-Salyers, BD, Burstein, LS & Mandel, ID (1981). Lipids associated with mineralization of human submandibular gland sialoliths. Arch Oral Biol 26, 779785.10.1016/0003-9969(81)90173-4
Capaccio, P, Torretta, S, Ottavian, F, Sambataro, G & Pignataro, L (2007). Modern management of obstructive salivary diseases. Acta Otorhinolaryngol Ital 27, 161172.
Daudon, M, Donsimoni, R, Hennequin, C, Fellahi, S, Le Moel, G, Paris, M, Troupel, S & Lacour, B (1995). Sex- and age-related composition of 10 617 calculi analyzed by infrared spectroscopy. Urol Res 23, 319326.
Dorozhkin, SV (2003). Mechanism of solid-state conversion of non-stoichiometric hydroxyapatite to diphase calcium phosphate. Russ Chem Bull 52, 2639–2375.
Dorozhkin, SV (2012). Calcium Orthophosphates: Applications in Nature, Biology, and Medicine. Singapore: Pan Stanford.
Escudier, MP, Brown, JE, Putcha, V, Capaccio, P & McGurk, M (2010). Factors influencing the outcome of extracorporeal shock wave lithotripsy in the management of salivary calculi. Laryngoscope 120, 15451549.
Feldkamp, LA, Davis, LC & Kress, JW (1984). Practical cone-beam algorithm. J Opt Soc Am A 1, 612619.
Geyer, LL, Schoepf, UJ, Meinel, FG, Nance, JW Jr., Bastarrika, G, Leipsic, JA, Paul, NS, Rengo, M, Laghi, A & De Cecco, CN (2015). State of the art: Iterative CT reconstruction techniques. Radiology 276, 339357.
Gomes, S, Renaudin, G, Mesbah, A, Jallot, E, Bonhomme, C, Babonneau, F & Nedelec, JM (2010). Thorough analysis of silicon substitution in biphasic calcium phosphate bioceramics: A multi-technique study. Acta Biomater 6, 32643274.
Gopal, R, Calvo, C, Ito, J & Sabine, WK (1974). Crystal structure of synthetic Mg-whitlockite, Ca18Mg2H2(PO4)14. Can J Chem 52, 11551164.
Grases, F, Santiago, C, Simonet, BM & Costa-Bauza, A (2003). Sialolithiasis: Mechanism of calculi formation and etiologic factors. Clin Chim Acta 334, 131136.
Habraken, WJ, Tao, J, Brylka, LJ, Friedrich, H, Bertinetti, L, Schenk, AS, Verch, A, Dmitrovic, V, Bomans, PH, Frederik, PM, Laven, J, van der Schoot, P, Aichmayer, B, de With, G, DeYoreo, JJ & Sommerdijk, NA (2013). Ion-association complexes unite classical and non-classical theories for the biomimetic nucleation of calcium phosphate. Nat Commun 4, 1507.
Harrison, JD (2009). Causes, natural history, and incidence of salivary stones and obstructions. Otolaryngol Clin North Am 42, 927947.
Hasgall, PA, Di Gennaro, F, Baumgartner, C, Neufeld, E, Gosselin, MC, Payne, D, Klingenböck, A & Kuster, N (2015). IT'IS Database for thermal and electromagnetic parameters of biological tissues, Version 3.0.
Heimbach, D, Munver, R, Zhong, P, Jacobs, J, Hesse, A, Muller, SC & Preminger, GM (2000). Acoustic and mechanical properties of artificial stones in comparison to natural kidney stones. J Urol 164, 537544.
Ho, SP, Hsi, RCL, Yang, F, You, S, Killilea, D, Ramaswam, K, Chang, J, Chi, T & Stoller, M (2016). Kidney stones compared to dental calculi and salivary stones: Comparative analyses of mineral density and ultrastructure. J Urol 195, e778e779.
Jayasree, RS, Gupta, AK, Vivek, V & Nayar, VU (2008). Spectroscopic and thermal analysis of a submandibular sialolith of Wharton's duct resected using Nd:YAG laser. Lasers Med Sci 23, 125131.
Kalia, V, Kalra, G, Kaur, S & Kapoor, R (2015). CT scan as an essential tool in diagnosis of non-radiopaque sialoliths. J Maxillofac Oral Surg 14, 240244.
Koch, M, Schapher, M, Mantsopoulos, K, von Scotti, F, Goncalves, M & Iro, H (2017). Multimodal treatment in difficult sialolithiasis: Role of extracorporeal shock-wave lithotripsy and intraductal pneumatic lithotripsy. Laryngoscope 128, E332E338.
Kong, J & Yu, S (2007). Fourier transform infrared spectroscopic analysis of protein secondary structures. Acta Biochim Biophys Sin (Shanghai) 39, 549559.
Kraus, W & Nolze, G (1996). POWDER CELL—a program for the representation and manipulation of crystal structures and calculation of the resulting X-ray powder patterns. J Appl Crystallogr 29, 301303.10.1107/S0021889895014920
Lambda, R, McGahan, JP, Corwin, MT, C-S, L, Tran, T, Seibert, JA & Boone, JM (2014). CT Hounsfield of soft tissues on unenhanced abdominal CT scans: Variability between two different manufacturers MDCT scanners. Genitourinary Imaging 203, 10131020.
LeGeros, RZ (1991). Calcium phosphates in oral biology and medicine. Monogr Oral Sci 15, 1201.
LeGeros, RZ, Sakae, T, Bautista, C, Retino, M & LeGeros, JP (1996). Magnesium and carbonate in enamel and synthetic apatites. Adv Dent Res 10, 225231.
Li, Y, Reid, GD, Bazin, D, Daudon, M & Duer, MJ (2016). Solid state NMR of salivary calculi: Proline-rich salivary proteins, citrate, polysaccharides, lipids, and organic–mineral interactions. C R Chim 19, 16651671.10.1016/j.crci.2015.07.001
Mahamid, J, Aichmayer, B, Shimoni, E, Ziblat, R, Li, C, Siegel, S, Paris, O, Fratzl, P, Weiner, S & Addadi, L (2010). Mapping amorphous calcium phosphate transformation into crystalline mineral from the cell to the bone in zebrafish fin rays. Proc Natl Acad Sci USA 107, 63166321.
Movasaghi, Z, Rehman, S & Rehman, I (2008). Fourier transform infrared (FTIR) spectroscopy of biological tissues. Appl Spectrosc Rev 43, 134179.
Nguyen, QD & Daudon, M (1997). Infrared et Raman Spectra of Calculi. Paris: Elsevier.
Nolasco, P, Anjos, AJ, Marques, JM, Cabrita, F, da Costa, EC, Mauricio, A, Pereira, MF, de Matos, AP & Carvalho, PA (2013). Structure and growth of sialoliths: Computed microtomography and electron microscopy investigation of 30 specimens. Microsc Microanal 19, 11901203.
Nolasco, P, Dos Anjos, AJ, Dias, J, Coelho, PV, Coelho, C, Evaristo, M, Cavaleiro, A, Mauricio, A, Pereira, MFC, Infante, V, Alves de Matos, AP, Martins, RC & Carvalho, PA (2017). Local response of sialoliths to lithotripsy: Cues on fragmentation outcome. Microsc Microanal 23, 584598.
Otsu, N (1979). A threshold selection method from gray-level histograms. EEE Trans Syst Man Cybern Syst 9, 6266.
Patrick, S, Birur, NP, Gurushanth, K, Raghavan, AS & Gurudath, S (2017). Comparison of gray values of cone-beam computed tomography with Hounsfield units of multislice computed tomography: An in vitro study. Indian J Dent Res 28, 6670.
Prionas, ND, Ray, S & Boone, JM (2010). Volume assessment accuracy in computed tomography: A phantom study. J Appl Clin Med Phys 11, 3037.
Rehman, I & Bonfield, W (1997). Characterization of hydroxyapatite and carbonated apatite by photo acoustic FTIR spectroscopy. J Mater Sci Mater Med 8, 14.
Russel, G, Robertson, WG & Fleich, H (1973). Inhibitors of mineralization. In Biological Mineralization, Zipkin, I (Ed.), pp. 807825. New York, USA: John Wiley and Sons.
Rzymska-Grala, I, Stopa, Z, Grala, B, Golebiowski, M, Wanyura, H, Zuchowska, A, Sawicka, M & Zmorzynski, M (2010). Salivary gland calculi—contemporary methods of imaging. Pol J Radiol 75, 2537.
Sabot, JF, Gustin, MP, Delahougue, K, Faure, F, Machon, C & Hartmann, DJ (2012). Analytical investigation of salivary calculi, by mid-infrared spectroscopy. Analyst 137, 20952100.
Sakae, T, Yamamoto, H & Hirai, G (1981). Mode of occurrence of brushite and whitlockite in a sialolith. J Dent Res 60, 842844.
Saw, KC, McAteer, JA, Monga, AG, Chua, GT, Lingeman, JE & Williams, JC Jr. (2000). Helical CT of urinary calculi: Effect of stone composition, stone size, and scan collimation. AJR Am J Roentgenol 175, 329332.
Schrotzlmair, F, Muller, M, Pongratz, T, Eder, M, Johnson, T, Vogeser, M, von Holzschuher, V, Zengel, P & Sroka, R (2015). Laser lithotripsy of salivary stones: Correlation with physical and radiological parameters. Lasers Surg Med 47, 342349.
Seldin, HM, Seldin, SD & Rakower, W (1953). Conservative surgery for the removal of salivary calculi. Oral Surg Oral Med Oral Pathol 6, 579587.
Skinner, HCW (2005). Biominerals. Mineral Mag 69, 621641.
SkyScan, NV (2005). SkyScan 1172 Desktop X-ray Microtomography Instruction Maunual. Aartselaar: N.V SkyScan.
Slomiany, BL, Murty, VL, Aono, M, Slomiany, A & Mandel, ID (1982). Lipid composition of the matrix of human submandibular salivary gland stones. Arch Oral Biol 27, 673677.
Szalma, J, Boddi, K, Lempel, E, Sieroslawska, AF, Szabo, Z, Harfouche, R, Olasz, L, Takatsy, A & Guttman, A (2013). Proteomic and scanning electron microscopic analysis of submandibular sialoliths. Clin Oral Investig 17, 17091717.
Tatón, G, Rokita, E, Wróbel, A, Beckmann, F & Thor, P (2010). Renal calculi composition studies with the use of microtomography. Cent European J Urol 6, 8790.
Williams, JC Jr., Kim, SC, Zarse, CA, McAteer, JA & Lingeman, JE (2004). Progress in the use of helical CT for imaging urinary calculi. J Endourol 18, 937941.
Wopenka, B & Pasteris, J (2005). A mineralogical perspective on the apatite in bone. Mater Sci Eng 25, 131143.
Xie, B, Halter, TJ, Borah, BM & Nancollas, GH (2015). Aggregation of calcium phosphate and oxalate phases in the formation of renal stones. Cryst Growth Des 15, 204211.
Zarse, CA, McAteer, JA, Tann, M, Sommer, AJ, Kim, SC, Paterson, RF, Hatt, EK, Lingeman, JE, Evan, AP & Williams, JC Jr (2004). Helical computed tomography accurately reports urinary stone composition using attenuation values: In vitro verification using high-resolution micro-computed tomography calibrated to Fourier transform infrared microspectroscopy. Urology 63, 828833.
Zhu, P, Lin, Y, Lin, H, Xu, Y, Zheng, Q & Han, Y (2014). Computational fluid dynamics analysis of salivary flow and its effect on sialolithogenesis. Oral Dis 20, 624630.


Type Description Title
Supplementary materials

Nolasco et al. supplementary material

 Word (91 KB)
91 KB


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed