whitlockite and Salivary-Gland-Calculi

The purpose of this paper was to describe the characteristics of salivary calculi and their relationship to epidemiological factors, through a cross-sectional study. We analysed 100 calculi obtained in 2017-2021. Patient data including age, time since onset of symptoms, gland involved, and site of location in the salivary system were studied. The calculi were studied to determine their morphological features using scanning electron microscopy and energy dispersive plain radiographic analysis. Most of the calculi had formed in the submandibular gland (SG) (82%). The mean age of patients at onset was 45.83 years; patients presenting parotid gland (PG) stones were somewhat older (p = 0.031). The mean time since the onset of symptoms was longer in PG calculi (p = 0.038). The most common lithiasis site was the main duct (74%), followed by the hilum (22%). Hilar stones were the largest (p < 0.05) and heaviest (p = 0.028). Octacalcium phosphate (OCP) was the most common crystalline phase (Cp) founded, followed by hydroxyapatite (HA) and whitlockite (WH). Specifically, OCP had a higher presence in PG calculi (p = 0.029) and WH was the most common phase in SG calculi (p = 0.017). The most prevalent site of lithiasis was the main duct, and the largest and heaviest calculi were found in the SG. PG stones were associated with a longer history of symptoms and older age. OCP was the most frequent Cp of the calculi studied, and the main Cp in PG stones. WH was the predominant Cp in SG stones. The Cp of the calculi was not influenced by location, patient age, or time of symptoms.

Topics: Cross-Sectional Studies; Endoscopy; Humans; Lithiasis; Middle Aged; Retrospective Studies; Salivary Duct Calculi; Salivary Gland Calculi

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.

Topics: Calcium Phosphates; Humans; Lithotripsy; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Minerals; Salivary Gland Calculi; Submandibular Gland; Tomography, Spiral Computed; Tomography, X-Ray Computed; X-Ray Diffraction; X-Ray Microtomography

The exact cause of the formation of sialoliths is unknown. Detailed knowledge of pathogenesis of sialolithiasis and composition of sialoliths is necessary to define new therapeutic procedures. The crystalline components of 23 sialoliths of human submandibular gland were investigated by X-ray powder diffraction analysis. All of the sialoliths localized in the ducts in the submandibular gland consisted of hydroxylapatite. However, in the sialoliths in the Wharton's duct, hydroxylapatite as well as whitlockite and brushite could be found in all except one case. Whitlockite was observed more often in the nucleus of the sialoliths and it was a common co-phase along with hydroxylapatite. The nucleus in one sialolith consisted of brushite and the cortex showed a co-phase of hydroxylapatite and brushite. The occurrence of whitlockite in the sialoliths in Wharton's duct may be due to a higher concentration of calcium and phosphate in saliva in this duct.

Topics: Adult; Aged; Calcium Phosphates; Crystallization; Durapatite; Female; Humans; Male; Middle Aged; Salivary Duct Calculi; Salivary Gland Calculi; Submandibular Gland Diseases; X-Ray Diffraction

The present study was performed to examine crystals in salivary calculus by high-resolution electron microscopy (HREM) and electron diffraction analyses. Microradiography (MR) showed that the calculus had three nuclei and showed complex shapes and mineralization. Hydroxyapatite (HA), in a variety of sizes and distributions, and the intermingling of HA and whitlockite (WH) at well-calcified areas, were observed.

Topics: Calcium Phosphates; Crystallography; Durapatite; Female; Humans; Microscopy, Electron; Middle Aged; Salivary Gland Calculi