Lactoferrin and the development of salivary stones: a pilot study

Salivary stones (sialoliths) are calcified structures located in the ductal system of the major salivary glands. Their exact cause is not clear but in general they are characterized by concentric inorganic (hydroxyapatite) layers. The formation is a slow intermittent process which may result in enlargement of the sialolith causing obstruction of saliva secretion resulting in mealtime related pain and swelling of the affected salivary gland. Various studies reported the presence of organic material such as proteins and lipids in the core of sialoliths. In the present study the protein composition of twenty submandibular sialoliths was analyzed. It was found that proteins contributed on average 5% to the dry weight of submandibular stones whereby small salivary stones contained more extractable proteins than large salivary stones. Using a combination of SDS-PAGE gel electrophoresis and Western blotting, we identified α-amylase (in all stones; 100%), lysozyme (95%), lactoferrin (85%), secretory-IgA (75%), MUC7 (60%), complement C4 (60%) and C-reactive protein (35%). The presence, and the combinations, of lactoferrin, lysozyme, s-IgA and α-amylase in sialoliths was confirmed by ELISA. The gradually increasing size of a sialolith might provoke a local inflammatory response in the duct of the submandibular gland whereby the relatively low concentrations of lactoferrin and lysozyme may originate from neutrophils. The interaction of lactoferrin with s-IgA could contribute to the accumulation of lactoferrin in sialoliths. In summary, these results suggest a new pathophysiological role for lactoferrin, in the formation of sialoliths.

Relationship between volume of submandibular salivary stones in vivo determined with Cone-Beam Computer Tomography and in vitro with micro-Computer Tomography

Background

Successful removal of salivary stones depends on exact pretreatment information of the location, the size and shape of the stones. This study aimed to compare the volume of submandibular sialoliths determined by preoperative Cone-Beam Computer Tomography (CBCT) scans with the volume of the removed stones on micro-Computer Tomography (micro-CT) scans.

Material and Methods

In this study, using twenty-one submandibular sialoliths, the pretreatment volumes in-vivo measured on CBCT were compared to the volumes of removed stones determined by micro-CT scans. The volume measured on micro-CT scans served as the gold standard. Pre-operative CBCT’s and in-vitro micro-CT’s were converted into standard tessellation language models (STL-models) using an image segmentation software package. The CBCT and micro-CT images of the stones were subsequently metrologically assessed and compared to each other using reverse engineering software.

Results

Volumes of submandibular sialoliths determined by CBCT’s correlated significantly with volumes measured on micro-CT’s (Spearman’s coefficient r = 0.916). The interquartile range (IQR) for the volume measured with micro-CT was 117.23. The median is 26.41. For the volume measured with CBCT the IQR was 141.3 and the median 36.61. The average volume on micro-CT is smaller than on CBCT.

Conclusions

When using CBCT-scans for the detection of submandibular sialoliths one should realize that in-vivo those stones are actually a fraction smaller than assessed on the preoperative scan. This is important when cut-off values of sizes of stones are used in the pretreatment planning of stone removal.

Key words:Salivary stone, sialolith, CBCT, micro-CT, volume.

Biochemical composition of salivary stones in relation to stone- and patient-related factors

BACKGROUND

Salivary stones are calcified structures most often found in the main duct of the submandibular or parotid salivary gland. They contain of a core surrounded by laminated layers of organic and inorganic material.

MATERIAL AND METHODS

Submandibular and parotid sialoliths (n=155) were collected at the department of Oral and Maxillofacial surgery of a general hospital between February 1982 and September 2012. The weight of the sialoliths was determined and the consistency was subjectively classified. Subsequently, the biochemical composition of the stones was determined by wet chemical methods or FT-IR spectrometry. Age and gender of the patients were retrieved from their medical records. Data were statistically analyzed using Fisher's exact tests.

RESULTS

Sialoliths are mainly composed of inorganic material. Carbonate apatite was identified in 99% of the stones, phosphate in 88%, calcium in 87%, magnesium in 68%, struvite in 44%, oxalate in 38% and carbonate in 35%. Solid salivary stones contain more frequently struvite than stones with a soft consistency (p=0.05). Larger stones (>100mg) contain more frequently carbonate (p=0.05). Stones from older patients (≥38years) showed an almost significant trend towards more frequent presence of phosphate (p=0.083).

CONCLUSIONS

The biochemical composition of submandibular and parotid sialoliths is related to stone-related factors, probably to age but not to the gender of the patient.

Systemic diseases and the risk of developing salivary stones: a case control study

OBJECTIVE

To investigate the possible relationship between the presence of salivary stones and systemic diseases, medication, smoking, and alcohol consumption.

STUDY DESIGN

A retrospective, case control study. Medical records of patients with salivary stones and those of control patients without salivary stones were retrospectively reviewed. Data regarding the affected salivary gland, the presence of systemic disease, and the use of medication, tobacco, and alcohol were recorded. Statistical analysis was performed using the Fisher Exact tests.

RESULTS

Medical records of 208 patients with salivary stones and those of 208 control patients were reviewed. Of the patients diagnosed with salivary stones, the submandibular gland was affected in 85.6% of the patients, the parotid gland in 9.6%, and the sublingual gland in 2.4% of the patients. None of the recorded systemic diseases was more prevalent in patients with salivary stones. Patients with salivary stones used significantly more antibiotics compared with the control group (P = .037). No significant differences were observed for other types of medication. There was no correlation between salivary stone formation, smoking, and alcohol consumption.

CONCLUSIONS

The present study suggested that systemic diseases, medication, smoking, and alcohol consumption play no or only a limited role in the onset of salivary stones.

[Salivary stones: aetiology, composition and treatment]

Salivary stones or sialoliths, are calcified concrements which are most frequently located in the submandibular glands and their ducts. Their size and weight show considerable variation. The aetiology is unknown. It has been suggested that salivary stones could be related to an altered saliva composition, the anatomy of the ducts of the salivary gland and/or the fusion of microsialoliths. Salivary stones consist mainly of anorganic material such as hydroxyapatite, whitlockite and calciumphosphate, but they also contain organic components such as proteins and lipids. Treatment can consist of salivary gland massage combined with an acid diet, ultrasonic pulverisation, and surgical or sialendoscopical removal.

A comparison of body fat estimates using anthropometry and bioelectrical impedance analysis with distinct prediction equations in elderly persons in the Republic of Guatemala

Bioelectrical impedance analysis (BIA) has been proposed as a technique to estimate body composition. Its application has extended beyond the clinical setting, however, it remains to be determined if the BIA prediction formulas published to date provide comparable body composition estimates in elderly populations. The objective of this study was to compare the estimates of body fat derived from published prediction equations in a developing country's population such as Guatemala. A total of 234 elderly persons were studied (108 males and 126 females), with ages of 78 +/- 7 and 77 +/- 8 (mean +/- SD) yr, respectively. The height and weight averaged 156.4 +/- 7.9 and 144.0 +/- 7.0 cm, and 54.5 +/- 9.4 and 49.4 +/- 10.6 kg, for males and females, respectively. Measurements included skinfolds (triceps, biceps, subscapular, and suprailiac), and body resistance (BIA). Body fat estimates were derived from four BIA-prediction formulas and three equations based on anthropometry. Mean percent body fat estimates for the overall population obtained from anthropometry and BIA prediction formulas ranged from 22 to 50%. Females had higher estimates compared to males without regard for the method used. Highly significant intermethod correlations were seen, but differences in fat estimation among prediction formulas were noticed and the magnitude of the differences were BIA-formula dependent.