Salivary stones: symptoms, aetiology, biochemical composition and treatment

Pediatric Salivary Gland Pathology

Benign and malignant salivary gland disorders are uncommon in the pediatric population; however, these can be frequently seen in pediatric otolaryngology or oral and maxillofacial surgery practices. The astute clinician should be aware of the clinical presentation, diagnosis, and management options for common inflammatory, infectious, benign, and malignant disorders of salivary glands.

Management of a Submandibular Sialolith: A Case Report

Sialolithiasis is a condition that is characterized by the obstruction of the salivary gland duct opening by calcified mineral deposits due to various factors discussed in this case report. The most common symptom associated with the pathology is difficulty in deglutition, which can often lead to dehydration due to poor water intake. This, in turn further increases the viscosity of saliva which further promotes the formation of sialoliths. The management is dictated by the location and size of the sialolith, and in this case report, the significance of conservative treatment is emphasized while acknowledging the importance of invasive treatment when necessary.

Microbiomic association between the saliva and salivary stone in patients with sialolithiasis

Salivary stones, known as sialoliths, form within the salivary ducts due to abnormal salivary composition and cause painful symptoms, for which surgical removal is the primary treatment. This study explored the role of the salivary microbial communities in the formation of sialoliths. We conducted a comparative analysis of microbial communities present in the saliva and salivary stones, and sequenced the 16S rRNA gene in samples obtained from patients with sialoliths and from healthy individuals. Although the diversity in the saliva was high, the essential features of the microbial environment in sialoliths were low diversity and evenness. The association of microbial abundance between stones and saliva revealed a positive correlation between Peptostreptococcus and Porphyromonas, and a negative correlation for Pseudomonas in saliva. The functional potential differences between saliva and stones Bacterial chemotaxis and the citrate cycle were negatively correlated with most genera found in salivary stone samples. However, the functions required for organic compound degradation did not differ between the saliva samples. Although some microbes were shared between the sialoliths and saliva, their compositions differed significantly. Our study presents a novel comparison between salivary stones and salivary microbiomes, suggesting potential preventive strategies against sialolithiasis.

What is the impact of previous cholelithiasis on sialolithiasis: A systematic review and meta-analysis

Introduction

A sialolith is a salivary stone usually presenting with swelling and pain in the affected salivary gland, most commonly the submandibular gland. There have been speculations about the association between this condition and other systemic diseases, especially those forming stones, such as nephrolithiasis and cholelithiasis. This systematic review and meta-analysis aimed to summarize the studies assessing the relationship between cholelithiasis and sialolithiasis.

Methods

PubMed/MEDLINE, Scopus, Web of Science, and Embase electronic databases were searched according to the keywords related to both disorders without any publication date or language restriction. Case-control and cohort studies evaluating the relationship between salivary and biliary stones were considered eligible. Quality assessment was performed following Newcastle-Ottawa Scale (NOS) for quality assessment of case-control studies. All meta and statistical analyses were performed with Comprehensive Meta-Analysis software.

Results

Two studies fully complied with the defined eligibility criteria and were included, both of which were case-control studies using national-scale databases. In both surveys, the prevalence of previous gallstones in patients with sialolithiasis was compared to that of a control group. Though one of the studies found that there is no relationship between sialolithiasis and cholelithiasis, the meta-analysis revealed that previous cholelithiasis is significantly more prevalent among patients with sialolithiasis (P = 0.000), with an odds ratio of 2.04.

Conclusion

It seems that cholelithiasis is significantly associated with an increase in salivary stone formation. Therefore, a thorough salivary examination in all patients declaring current or past cholelithiasis is recommended. However, more studies, especially prospective cohorts, are needed to make firmer conclusions.

Sialolithiasis in the Left Submandibular Gland: A Case

The most common illness affecting the salivary glands is submandibular gland sialoliths. The size of the sialolith and the patient's clinical history mainly influence how this salivary system abnormality is treated. This diagnosis is suggested by a history of salivary gland pain or swelling, particularly during mastication. Palliative therapy combined with conservative therapies, such as the milking of the ducts, can effectively treat small and accessible stones. When a stone or stones are large and inaccessible, surgical therapy should be considered if conservative approaches have not proven to be effective. A case of sialolithiasis affecting the left submandibular salivary gland is described in this article. Under local anesthesia, sialolith was removed following the opening of the duct. The wound was closed with sutures, and the patient was advised to practice tongue exercises and to maintain good oral hygiene.

Nanomechanical properties of kidney stones, gallstones and oral stones compared with tap water scale by depth sensing indentation

This article focuses on a description of research performed to identify structural and mechanical properties differences between calculi in stones, such as gallstones, kidney stones, dental tartar, and saliva gland sialolite, were analyzed and compared with tap water stone, in order to set interrelations. In this study, biological hard pebble-like structures were analyzed and compared among them using Scanning Electron Microscopy (SEM), X-Ray diffraction (XRD), and Atomic Force Microscopy (AFM). In addition, Nanoindentation was used to obtain values as example in kidney stones the in; stiffness S = 27,827 ± 620 N/nm elastic modulus E = 27.3 ± 4.5 GPa, hardness H = 1.5 ± 0.5 GPa. Samples with the highest amounts of calcium and magnesium oxides were; Tap water stone (39.60%), followed by dental tartar (39.40%), saliva gland sialolite (29.20%), kidney stones (27.70%), and lastly the gallstones (0.30%). Kidney stones showed in particular, whewellite and kaoulinite crystallographic phases, that confers characteristics of greater crystallization with respect to the other stones. Kidney stones positioned in the major hardness stone in human body with 1.5 GPa. In general, samples with the highest amount of calcium oxides, also showed the highest mechanical properties of H and E. Microstructural characteristics and nano-hardness of tap water stone from drinking water where similar to those of dental tartar and saliva gland sialolite, more research still required to associate health concerns and tap water scale derived from drinking water known as hardwater.

U-shaped fusion convolutional transformer based workflow for fast optical coherence tomography angiography generation in lips

Oral disorders, including oral cancer, pose substantial diagnostic challenges due to late-stage diagnosis, invasive biopsy procedures, and the limitations of existing non-invasive imaging techniques. Optical coherence tomography angiography (OCTA) shows potential in delivering non-invasive, real-time, high-resolution vasculature images. However, the quality of OCTA images are often compromised due to motion artifacts and noise, necessitating more robust and reliable image reconstruction approaches. To address these issues, we propose a novel model, a U-shaped fusion convolutional transformer (UFCT), for the reconstruction of high-quality, low-noise OCTA images from two-repeated OCT scans. UFCT integrates the strengths of convolutional neural networks (CNNs) and transformers, proficiently capturing both local and global image features. According to the qualitative and quantitative analysis in normal and pathological conditions, the performance of the proposed pipeline outperforms that of the traditional OCTA generation methods when only two repeated B-scans are performed. We further provide a comparative study with various CNN and transformer models and conduct ablation studies to validate the effectiveness of our proposed strategies. Based on the results, the UFCT model holds the potential to significantly enhance clinical workflow in oral medicine by facilitating early detection, reducing the need for invasive procedures, and improving overall patient outcomes.

An Aberrant Case of Large Submandibular Gland Sialolith With Obstructive Sialadenitis in a Young Female

Sialolithiasis is a major cause of salivary gland dysfunction. Submandibular sialolithiasis with obstructive sialadenitis is a relatively uncommon condition. Submandibular gland sialolithiasis with obstructive sialadenitis accounts for about 2% of all cases of sialadenitis. We are reporting a case of a 20-year-old female who presented with acute-onset swelling in the right submandibular region. The submandibular gland had a large calculus with pericalcular abscess development, which was clearly visible on pre- and post-contrast computed tomography. Subsequently, surgical excision of the lesion was performed, and calculus was removed.

Sialolithiasis: An Unusually Large Submandibular Salivary Stone

Salivary stones are termed as sialoliths, and the condition is referred to as sialolithiasis. Pain and swelling in the affected area, especially after eating, occur often. Small, easily accessible stones may be managed with conservative methods, such as milking of ducts, along with palliative care, whereas bigger, more difficult-to-reach stones need surgical removal. In this article, we describe a case of sialolithiasis affecting the right submandibular salivary gland, which was treated by removing the gland and stone surgically. When big stones and the gland are removed extra orally, the results are favorable. Submandibular gland sialoliths are the most frequent kind of salivary gland illness. The treatment of this salivary system problem depends on the patient's clinical history, the size of the sialolith, and the degree of cooperation.

Evaluation and management of temporomandibular disorders. Part 2: an orthopaedic physical therapy update on examination and clinical reasoning

Temporomandibular (TM) disorders afflict many people globally and, despite the presence of existing peer-reviewed material that assists conservative orthopedic providers, recent advances in knowledge indicate that updated resources are required for students, clinicians, and educators. This two-part series builds off previously published material to present newer supplementary information that can be useful during the evaluation and management processes. Content in Part 1 of this series includes a discussion about the factors that have been shown to contribute to TM disorders, an updated perspective of relevant pain science, a discussion of self-report outcome measures, and various different topics related to the examination of patients with TM disorders. Part 2 addresses information related to the temporomandibular joint disc, joint hypermobility, oral splints, and clinical reasoning. In combination with other available publications, this two-part series provides clinicians an opportunity to improve their delivery of effective and efficient clinical services for people diagnosed with TM disorders.

Recovery of gland function after endoscopy-assisted removal of impacted hilo-parenchymal stones in the Wharton's duct

The aim of this study was to evaluate the gland function of patients following endoscopy-assisted removal of impacted hilo-parenchymal stones in the Wharton's duct. The study cohort comprised 115 patients who had undergone successful endoscopy-assisted lithotomy for hilo-parenchymal stones (mean diameter 7.7 mm). Gland function was evaluated at a mean 12 months after surgery using ultrasonography, sialography, and/or sialometry. Postoperative ultrasonography of 51 affected glands revealed a regular gland size in 58.8%, normal parenchyma density in 51.0%, and ductal ectasia in 80.4%. Postoperative sialograms of 109 affected glands were scored as type I (approximately normal) in 13 cases, type II (saccular ectasia of the hilo-parenchymal duct with/without stenosis, and no contrast retention) in 64, type III (saccular ectasia of the hilo-parenchymal duct with/without stenosis, and mild contrast retention) in 23, and type IV (poor shape of the main duct with evident contrast retention) in nine cases. The existence of ductal ectasia corresponded well to larger stone cases (P = 0.002). In the postoperative sialometry of 35 patients with unilateral stones, differences between the two sides were insignificant (P > 0.05). For patients with hilo-parenchymal submandibular gland stones, endoscopy-assisted surgery and extended postoperative follow-up help preserve the gland with good function.

Proteomic analysis of sialoliths from calcified, lipid and mixed groups as a source of potential biomarkers of deposit formation in the salivary glands

Salivary stones, also known as sialoliths, are formed in a pathological situation in the salivary glands. So far, neither the mechanism of their formation nor the factors predisposing to their formation are known despite several hypotheses. While they do not directly threaten human life, they significantly deteriorate the patient's quality of life. Although this is not a typical research material, attempts are made to apply various analytical tools to characterise sialoliths and search for the biomarkers in their proteomes. In this work, we used mass spectrometry and SWATH-MS qualitative and quantitative analysis to investigate the composition and select proteins that may contribute to solid deposits in the salivary glands. Twenty sialoliths, previously characterized spectroscopically and divided into the following groups: calcified (CAL), lipid (LIP) and mixed (MIX), were used for the study. Proteins unique for each of the groups were found, including: for the CAL group among them, e.g. proteins from the S100 group (S100 A8/A12 and P), mucin 7 (MUC7), keratins (KRT1/2/4/5/13), elastase (ELANE) or stomatin (STOM); proteins for the LIP group-transthyretin (TTR), lactotransferrin (LTF), matrix Gla protein (MPG), submandibular gland androgen-regulated protein 3 (SMR3A); mixed stones had the fewest unique proteins. Bacterial proteins present in sialoliths have also been identified. The analysis of the results indicates the possible role of bacterial infections, disturbances in calcium metabolism and neutrophil extracellular traps (NETs) in the formation of sialoliths.

Treatment outcomes of sialendoscopy for submandibular gland sialolithiasis

OBJECTIVE

Sialendoscopy is a procedure used to remove salivary stones intraorally using a sialendoscope. In this study, we identified treatment outcomes of sialendoscopic surgery and identified predictive factors for successful stone removal by sialendoscopy alone.

METHODS

We assembled the medical records of 144 patients who underwent sialendoscopic surgery for submandibular gland sialolithiasis at the Department of Otolaryngology-Head and Neck Surgery, Asahikawa Medical University, from October 2010 to November 2021, and collected patient backgrounds, medical condition, perioperative factors including operation method and complications, postoperative course, and stone constituents from a clinical laboratory testing company.

RESULTS

Submandibular gland stones were successfully removed using sialendoscopy in 58 patients (40%). In multivariate analysis, location, major axis, and mobility of the stones were independent factors for successful removal. In receiver operating characteristic analysis, <7.5 mm of a major axis may be used as a measuring standard for successful removal. Removal of parenchymal stones is prone to involve prolonged operation times, increased postoperative complications, and development of retained stones. The stones mainly consisted of calcium phosphate and protein, with content percentages ranging from 0 to 98% (median 37%) and from 0 to 100% (median 63%), respectively. The percentage of calcium phosphate was negatively correlated with the number of floating stones and successful stone removal.

CONCLUSION

Sialendoscopy is an aesthetically attractive treatment for sialolithiasis that avoids cervical incisions. The present results showed not only known but also new predictive factors for the successful removal of stones (<7.5 mm) and percentage of calcium phosphate. Moreover, our results suggest that careful consideration is required regarding the indication of sialendoscopic surgery in patients with parenchymal stones.

Sialolithiasis: mineralogical composition, crystalline structure, calculus site, and epidemiological features

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.

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.

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.

Impaired spontaneous secretion as a potential factor in the development of sialolithiasis in the submandibular gland: A preliminary sialoscintigraphic study

Objectives

The development of sialolithiasis is commonly related to local factors, such as the retrograde migration of foods, bacteria, or foreign bodies from the oral cavity. The association of sialolithiasis and saliva stasis resulting from decreased spontaneous secretion remains largely unexplored. The current study investigated the potential role of impaired spontaneous secretion in association with the formation of submandibular gland calculi.

Study Design

A retrospective cohort study.

Methods

Between September 2016 and December 2017, 11 patients with unilateral submandibular gland sialolithiasis confirmed with sialendoscopy were assigned to the experimental group. Another 35 patients clinically diagnosed with parotid obstructive sialadenitis were assigned as the control group. The slope changes of the isotope count curve of the unaffected submandibular gland in the experimental group and the bilateral submandibular glands in the control group were calculated and compared to estimate the spontaneous secretion differences. The degree of spontaneous secretion was defined as the slope changes in the steady ascending stage of the scintigraphic exam.

Results

The slope decline (degree of spontaneous secretion) on the unaffected side in patients with single-gland submandibular obstructive sialadenitis was significantly lower than that in the control individuals (p = .002). In contrast, the between-group comparison in the unaffected parotid glands revealed no difference in the slope decline.

Conclusion

The spontaneous secretion of the submandibular gland in patients with submandibular sialolithiasis was decreased compared to that in patients without submandibular sialolithiasis. This phenomenon might be associated with the development of sialolithiasis.

Level of Evidence

3.

The changing landscape of pediatric salivary gland stones: A half-century systematic review

OBJECTIVE

To assess the evidence for pediatric sialolithiasis, including its demographic characteristics, diagnosis, and demonstrate the shift in its treatment paradigm.

DESIGN

A systematic review of sources from the Medline and Embase databases was conducted from inception to Dec 4, 2020. Two researchers independently extracted data and assessed quality.

PATIENTS

Patients under the age of 18 with sialolithiasis were included.

MAIN OUTCOME MEASURES

Study design, cohort size, age, sex, symptoms, stone characteristics, diagnostic modality and intervention were collected data points.

RESULTS

Forty-one studies with 243 patients were included in the review, of which 40 were case reports or series. Most stones were found in the submandibular gland (n = 210, 85.4%) and were single stones (n = 101, 71.1%). Average stone size was 7.7 mm. The most common diagnostic imaging modality used was ultrasound (n = 73, 47.4%), shifting from plain radiograph which was favoured in earlier years. Similarly, open gland excision was historically preferred, but since 2000, sialoendoscopy comprised 40.5% of all treatment modalities and continues to increase in prevalence, up to 52.1% by 2020. Extracorporeal shock wave lithotripsy was associated with the highest complication rate of 54.2%.

CONCLUSIONS

The pediatric sialolithiasis diagnostic and therapeutic landscape has changed with ultrasound replacing plain radiographs, and sialoendoscopy replacing submandibular gland excision. Further high-level quality evidence research is required to refine the indications, effectiveness, and safety of sialoendoscopy in pediatric sialolithiasis.

Multiple Faces of Cervical Lesions in Children

Pediatric sialolithiasis is a rare condition causing tumefaction, induration, redness, and pain of the affected gland. When the submandibular gland is involved, the lesion can be mistaken for an adenopathy. As there are few studies to elucidate this condition in children, we present a rare case of a 16-year-old female with suggestive symptoms, in which initial clinical examination and two ultrasound examinations mistook the lesion for an adenopathy. A computed tomography examination was performed and the correct diagnosis was established. The patient was sent for oro-maxilo-facial examination and sialolithotomy was performed. A 10-mm yellow calculus was extracted and postoperative case evolution was favorable under wide spectrum antibiotherapy, oral nonsteroidal anti-inflammatory therapy and silagog alimentation. Although submandibular adenopathies are much more frequent in the pediatric age group, when faced with a firm, immobile submandibular lesion, the pediatrician should consider the sialolithiasis diagnosis.

Rapid development of a salivary calculus in submandibular gland and its potential causes in a young victim following Russell's viper bite

Russell's viper bites are known to cause a range of haemotoxic, neurotoxic, myotoxic, cytotoxic and nephrotoxic complications. However, the impact of Russell's viper bites as well as bites from other venomous snakes on sialolithiasis has not been previously reported. Here, we present an interesting case where a Russell's viper bite induced the rapid development of a calculus in submandibular gland in a 10-year-old boy. Upon admission, the victim did not show any symptoms of swelling and/or pain around his oral cavity. He received antivenom treatment to normalise his coagulation parameters, however, on day three he developed swelling and extreme pain around his right mandibular region. An ultrasound investigation revealed the presence of a calculus in his submandibular gland, which was removed using a minor surgical procedure. The histopathological examination revealed this as a poorly calcified salivary calculus, which is composed of cell debris, mucopolysaccharides and lipids. The mechanisms behind its rapid development following a snakebite are unclear although this could be linked to excessive inflammation or modifications to the composition of saliva induced by venom toxins or other unknown factors. This report reveals an unusual complication induced by a Russell's viper bite and alerts clinicians who treat snakebites to be aware of such envenomation effects. Moreover, this will lead to novel research to explore the relationship between venom toxins and functions of salivary glands.

Utility of Ultrasonography for Diagnosis of Salivary Gland Sialolithiasis: A Meta-Analysis

OBJECTIVES

We hypothesized that ultrasonography for salivary gland stone detection would have a diagnostic accuracy similar to that confirmed by sialendoscopy, sialography, or surgery. Therefore, we evaluated the diagnostic characteristics of ultrasonography in terms of submandibular and parotid stone detection compared to confirmatory methods.

METHODS

We searched PubMed, Embase, the Web of Science, SCOPUS, and the Cochrane database to October 31, 2021. The risk of bias was evaluated using the QADAS-2 tool.

RESULTS

Ten studies involving 1393 patients were included in the analysis. The diagnostic odds ratio of ultrasonography was 162.6013 (95% confidence interval [CI] [53.9883; 489.7208] and I² value 81.0%). The area under the summary receiver operating characteristic curve was 0.963. The sensitivity, specificity, negative predictive value, and positive predictive value were 0.8992 (95% CI [0.8534; 0.9318]; I²  = 79.9%), 0.9664 (95% CI [0.9290; 0.9844], I²  = 65.6%), 0.8076 (95% CI [0.7256; 0.8694]; I²  = 80.4%), and 0.9853 (95% CI [0.9629; 0.9943]; I²  = 77.4%), respectively. However, high-level among-study heterogeneity (I²  ≥ 50%) was evident, attributable to the inclusion of different glands. On subgroup analysis, significant differences in the negative predictive values (parotid gland only [0.9392], submandibular gland only [0.6718], and parotid and submandibular glands [0.8105]) were apparent. We found no significant among-study difference in the sensitivity, specificity, positive predictive value, or diagnostic odds ratio (P > .05).

CONCLUSION

Ultrasonography usefully detects submandibular and parotid gland stones. Ultrasonography of the parotid gland was associated with the highest diagnostic accuracy, but further clinical studies are needed.

LEVEL OF EVIDENCE

NA Laryngoscope, 2022.

The Translational Role of MUC8 in Salivary Glands: A Potential Biomarker for Salivary Stone Disease?

Mucin (MUC) 8 has been shown to play an important role in respiratory disease and inflammatory responses. In the present study, we investigated the question of whether MUC8 is also produced and secreted by salivary glands and whether it may also play a role in the oral cavity in the context of inflammatory processes or in the context of salivary stone formation. Tissue samples from parotid and submandibular glands of body donors (n = 6, age range 63–88 years), as well as surgically removed salivary stones from patients (n = 38, age range 48–72 years) with parotid and submandibular stone disease were immunohistochemically analyzed targeting MUC8 and TNFα. The presence of MUC8 in salivary stones was additionally analyzed by dot blot analyses. Moreover, saliva samples from patients (n = 10, age range 51–72 years), who had a salivary stone of the submandibular gland on one side were compared with saliva samples from the other “healthy” side, which did not have a salivary stone, by ELISA. Positive MUC8 was detectable in the inter- and intralobular excretory ducts of both glands (parotid and submandibular). The glandular acini showed no reactivity. TNFα revealed comparable reactivity to MUC8 in the glandular excretory ducts and also did not react in glandular acini. Salivary stones demonstrated a characteristic distribution pattern of MUC8 that differed between parotid and submandibular salivary stones. The mean MUC8 concentration was 71.06 ng/mL in female and 33.21 ng/mL in male subjects (p = 0.156). Saliva from the side with salivary calculi contained significantly (15-fold) higher MUC8 concentration levels than saliva from the healthy side (p = 0.0005). MUC8 concentration in salivary stones varied from 4.59 ng/mL to 202.83 ng/mL. In females, the MUC8 concentration in salivary stones was significantly (2.3-fold) higher, with an average of 82.84 ng/mL compared to 25.27 ng/mL in male patients (p = 0.034). MUC8 is secreted in the excretory duct system of salivary glands and released into saliva. Importantly, MUC8 salivary concentrations vary greatly between individuals. In addition, the MUC8 concentration is gender-dependent (♀ > ♂). In the context of salivary stone diseases, MUC8 is highly secreted in saliva. The findings support a role for MUC8 in the context of inflammatory events and salivary stone formation. The findings allow conclusions on a gender-dependent component of MUC8.

Trial Proteomic Qualitative and Quantitative Analysis of the Protein Matrix of Submandibular Sialoliths

Our studies aimed to explore the protein components of the matrix of human submandibular gland sialoliths. A qualitative analysis was carried out based on the filter aided sample preparation (FASP) methodology. In the protein extraction process, we evaluated the applicability of the standard demineralization step and the use of a lysis buffer containing sodium dodecyl sulfate (SDS) and dithiothreitol (DTT). The analysis of fragmentation spectra based on the human database allowed for the identification of 254 human proteins present in the deposits. In addition, the use of multi-round search in the PEAKS Studio program against the bacterial base allowed for the identification of 393 proteins of bacterial origin present in the extract obtained from sialolith, which so far has not been carried out for this biological material. Furthermore, we successfully applied the SWATH methodology, allowing for a relative quantitative analysis of human proteins present in deposits. The obtained results correlate with the classification of sialoliths proposed by Tretiakow. The performed functional analysis allowed for the first time the selection of proteins, the levels of which differ between the tested samples, which may suggest the role of these proteins in the calcification process in different types of sialoliths. These are preliminary studies, and drawing specific conclusions requires research on a larger group, but it provides us the basis for the continuation of the work that has already begun.

Painless Giant Submandibular Gland Sialolith: A Case Report

Sialolithiasis is one of the most common diseases involving the salivary glands. It is a condition that occurs due to an obstruction in a salivary gland or its duct due to a calculus. The formation of a salivary stone is believed to be secondary to the deposition of mineral salts around a nidus, which is frequently associated with a recurrent bacterial infection. Patients with submandibular sialolithiasis usually present with acute swelling over the neck associated with pain, fever, and purulent intraoral discharge. The size of the calculus varies from <1 mm to a few centimeters. The frequency of sialolithiasis is relatively common. It is estimated to affect 12 in 1000 of the adult population. However, the occurrence of giant sialoliths, >15 mm in any diameter, is rare. Here, we describe our experience with a case of giant submandibular sialolithiasis measuring 25 mm presenting as a painless submandibular mass. The patient underwent submandibular gland excision followed by a full recovery.

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.

Ectopic mineralisation of the mandibular symphysis in ENT1 knockout mice: A model of dystrophic calcification

Equilibrative nucleoside transporter 1 (ENT1) transfers nucleosides, such as adenosine, across plasma membranes. We reported previously that mice lacking ENT1 (ENT1 ^-/- ) exhibit progressive ectopic calcification of spinal tissues-a phenotype resembling diffuse idiopathic skeletal hyperostosis (DISH) in humans. Our objective was to investigate potential calcification of orofacial tissues in ENT1 ^-/- mice. Heads of wild-type mice and ENT1 ^-/- mice from 3 to 17 months were evaluated using microcomputed tomography (μCT). Some heads were decalcified and processed for histological assessment. Other heads were examined using energy dispersive X-ray spectroscopy and micro X-ray diffraction. Using μCT, ENT1 ^-/- mice showed extensive radiopaque lesions within the mandibular symphysis, the severity of which increased with advancing age. Histologically, at 6 months these ectopic radiopacities were found to correspond to acellular, amorphous, eosinophilic material, with no evidence of inflammatory cells. Because lesions were localised to the symphysis, we identified early pathological changes at 3 months and observed that lesions initiated specifically within the fibrocartilage pad. Energy-dispersive X-ray spectroscopy of ectopic lesions revealed large amounts of calcium and phosphorous in a molar ratio of ~1.59, and X-ray diffraction profiles matched that of calcium-deficient hydroxyapatite. This is the first characterisation of ectopic calcifications within the mandibular symphysis of ENT1 ^-/- mice, indicating a role for ENT1 and adenosine metabolism in regulating calcification of fibrocartilaginous tissues. Moreover, these murine lesions resemble areas of dystrophic calcification in the spinal tissues of humans with DISH. Importantly, ectopic calcifications develop in a reproducible temporal pattern within a well-defined anatomical region and, thus, provide a model for determining the cellular and molecular pathways underlying ectopic calcification in DISH and related disorders.

Concurrent giant sialoliths within the submandibular gland parenchyma and distal segment of Wharton's duct: Novel case report

OBJECTIVE

This article discusses the clinical significance of an unusual case of the simultaneous occurrence of 2 giant sialoliths within the ipsilateral submandibular gland and distal aspect of Wharton's duct in a 63-year-old patient.

BACKGROUND

The majority of submandibular gland sialoliths are found in Wharton's duct, with fewer within the gland parenchyma. Giant sialoliths (exceeding 15 mm in size) are rare.

MATERIALS AND METHODS

An asymptomatic, otherwise healthy older patient sought dental care and underwent a comprehensive oral and radiographic examination.

RESULTS

A panoramic radiograph revealed 2 incidental radiopaque structures, representing giant sialoliths within the submandibular gland and along the distal segment of Wharton's duct. This synchronous finding apparently represents the first case reported in the geriatric literature.

CONCLUSIONS

The detection of 1 salivary stone should heighten the scrutiny for additional stones. Practitioners should carefully weigh the risk of sialolith removal versus deferment of treatment in older medically compromised patients.

Classification of submandibular salivary stones based on ultrastructural studies

INTRODUCTION

Sialolithiasis remains a clinical problem with unclear etiopathogenesis, lack of prevention methods, and only surgical treatment.

MATERIALS AND METHODS

An ultrastructure examination of submandibular sialoliths obtained from patients with chronic sialolithiasis was conducted using a scanning electron microscope and X-ray photoelectron spectroscopy.

RESULTS

Based on the results, we divided sialoliths into three types: calcified (CAL), organic/lipid (LIP), and mixed (MIX). The core structure of the CAL and MIX is very similar. The core of the LIP has a prevalence of organic components. The intermediate layers' structure of the CAL is different from LIP and MIX. In LIP and MIX, the organic component begins to increase in intermediate layers rapidly. The structure of the superficial layers for all types of sialoliths is similar.

CONCLUSIONS

We introduced a new classification of the submandibular salivary gland stones. Based on the results, it can be said that sialoliths type CAL and LIP have their separate path of origin and development, while MIX is formed as CAL stone, and the further pathway of their growth passes as LIP stones. Organic components were much more than inorganic in all layers of salivary gland stones, which highly prevents their dissolution in the patient's salivary gland duct.

Neutrophil Extracellular Traps Promote the Development and Growth of Human Salivary Stones

Salivary gland stones, or sialoliths, are the most common cause of the obstruction of salivary glands. The mechanism behind the formation of sialoliths has been elusive. Symptomatic sialolithiasis has a prevalence of 0.45% in the general population, is characterized by recurrent painful periprandial swelling of the affected gland, and often results in sialadenitis with the need for surgical intervention. Here, we show by the use of immunohistochemistry, immunofluorescence, computed tomography (CT) scans and reconstructions, special dye techniques, bacterial genotyping, and enzyme activity analyses that neutrophil extracellular traps (NETs) initiate the formation and growth of sialoliths in humans. The deposition of neutrophil granulocyte extracellular DNA around small crystals results in the dense aggregation of the latter, and the subsequent mineralization creates alternating layers of dense mineral, which are predominantly calcium salt deposits and DNA. The further agglomeration and appositional growth of these structures promotes the development of macroscopic sialoliths that finally occlude the efferent ducts of the salivary glands, causing clinical symptoms and salivary gland dysfunction. These findings provide an entirely novel insight into the mechanism of sialolithogenesis, in which an immune system-mediated response essentially participates in the physicochemical process of concrement formation and growth.

Sialo-cutaneous fistula with ectopic submandibular gland sialolith, revealing a hidden ipsilateral enlarged and elongated styloid process: a consideration based on CT findings

Sialolithiasis is a common salivary pathology, and an uncommon complication of sialadenitis and sialolithiasis is the formation of fistulous tracts to other compartments. Submandibular gland sialo-oral fistulae are not particularly remarkable, given the location of the gland and Wharton's duct, but submandibular sialolith-associated fistulae to other cervico-facial compartments (transcervical sialo-cutaneous and sialo-pharyngeal fistulae) are much less common. We report herein an unusual case of a 49-year-old obese man with sialo-cutaneous fistula containing a large, ectopic sialolith in subcutaneous tissue that was expected to undergo spontaneous elimination, but revealed hidden Eagle syndrome featuring an ipsilateral enlarged, elongated styloid process. Furthermore, we offer a thorough review of the literature regarding sialo-fistulae and highlight the relationship between an abnormal styloid process and submandibular sialadenitis with sialolithiasis and new tract formation based on computed tomography.

Sialolithiasis-Do Early Diagnosis and Removal Minimize Post-Operative Morbidity?

Background and objectives: Sialolithiasis is an inflammation of a salivary gland due to obstruction of salivary flow by a sialolith. We aim to assess potential factors that may predict lower morbidity following endoscopically assisted per-oral sialolith removal. Materials and Methods: Retrospective cohort study. Retrospective review of 100 records of patients with sialolithiasis, following surgical sialolith removal. A single medical center (Department of oral and maxillofacial surgery-Rabin Medical Center, Beilinson & Hasharon-Israel) survey. Data were gleaned from the patient files based on a structured questionnaire. Factors that may predict morbidity were evaluated using linear regression equation. Results: 59 of the subjects were men and 41 were women. The mean age of the patients in the study was 50 ± 17.5 years. Sialolith volume and past antibiotic treatment were positively associated while age was negatively associated with hospitalization duration. Conclusion: Early sialolith diagnosis and removal may lower postoperative morbidity.

A comprehensive analysis of sialolith proteins and the clinical implications

BACKGROUND

Sialolithiasis or salivary gland stones are associated with high clinical morbidity. The advances in the treatment of sialolithiasis has been limited, however, by our understanding of their composition. More specifically, there is little information regarding the formation and composition of the protein matrix, the role of mineralogical deposition, or the contributions of cell epithelium and secretions from the salivary glands. A better understanding of these stone characteristics could pave the way for future non-invasive treatment strategies.

METHODS

Twenty-nine high-quality ductal stone samples were analyzed. The preparation included successive washings to avoid contamination from saliva and blood. The sialoliths were macerated in liquid nitrogen and the maceration was subjected to a sequential, four-step, protein extraction. The four fractions were pooled together, and a standardized aliquot was subjected to tandem liquid chromatography mass spectrometry (LCMS). The data output was subjected to a basic descriptive statistical analysis for parametric confirmation and a subsequent G.O.-KEGG data base functional analysis and classification for biological interpretation.

RESULTS

The LC-MS output detected 6934 proteins, 824 of which were unique for individual stones. An example of our sialolith protein data is available via ProteomeXchange with the identifier PXD012422. More important, the sialoliths averaged 53% homology with bone-forming proteins that served as a standard comparison, which favorably compared with 62% homology identified among all sialolith sample proteins. The non-homologous protein fraction had a highly variable protein identity. The G.O.-KEGG functional analysis indicated that extracellular exosomes are a primary cellular component in sialolithiasis. Light and electron microscopy also confirmed the presence of exosomal-like features and the presence of intracellular microcrystals.

CONCLUSION

Sialolith formation presents similarities with the hyperoxaluria that forms kidney stones, which suggests the possibility of a common origin. Further verification of a common origin could fundamentally change the way in which lithiasis is studied and treated.

Ultrastructural analysis of the submandibular sialoliths: Raman spectroscopy and electron back-scatter studies

The aim of work was the epidemiological analysis of the occurrence of sialolithiasis of the submandibular gland in adults and the evaluation of the ultrastructure of salivary stones. The study sample consisted of 44 sialoliths. Analysis of the structure and chemical composition of sialoliths was performed using a Scanning Electron Microscope and Raman Spectroscopy. Comparing our results with the literature we can say that the epidemiology of sialolithiasis has not changed significantly over the past 50 years. A wide variety of sialoliths structure was observed. In 75% (33) cases a layered structure of salivary stones was observed, while in 25% (11) - homogeneous structure. The various distribution of organic and inorganic components was observed among all the analyzed sialoliths. Raman spectroscopy allows for preliminary analysis of the sialoliths structure with only a qualitative assessment of their composition, which significantly reduces the research value of this method. The presence of organic and inorganic compounds in the core and inner layers of the salivary glands stones confirms 2 basic theories of the formation of sialoliths: inflammation and deposition of the inorganic component as a result of disruption of saliva flow in the salivary glands.

Sialolithiasis with abscess: An uncommon presentation of a Ludwig's angina mimic

Sialolithiasis represents the most common issue of the salivary gland, ranging from asymptomatic to airway compromising. In rapidly progressing, completely obstructive salivary stones, the presentation can mimic emergent oropharyngeal diseases, primarily Ludwig's angina. We present a case of a large and obstructive sialolith with abscess whose initial presentation was concerning for Ludwig's angina with impending airway compromise. While a common complaint, emergency providers should be aware of the nefarious presentation of an everyday complaint.

Salivary Gland Diseases

A variety of diseases ranging from obstructions, infections, to benign and malignant tumors occur in salivary glands. The most common problem is painful blockage of ducts by stones that prevents drainage of saliva. Sialadenitis can be due to either infectious or noninfectious factors. Bacterial or viral infections are the most common causes of acute sialadenitis. Staphylococcus is the usual bacterial cause, whereas paramyxovirus (mumps) is the common viral cause. Eighty percent of salivary tumors are benign, whereas about 20% are malignant. Most tumors occur in the parotid gland and on the hard palate. Classifications, imaging, and suggested treatment are described.

Dual-Source Dual-Energy CT in Submandibular Sialolithiasis: Reliability and Radiation Burden

OBJECTIVE. This study aims to compare the diagnostic accuracy of virtual unenhanced CT images derived from dual-source dual-energy contrast-enhanced CT with that of standard unenhanced CT images for evaluation of sialolithiasis. MATERIALS AND METHODS. All dual-energy CT studies of the neck performed during the preceding 5 years were reviewed for submandibular gland calculi. Only patients who had unenhanced CT and contrast-enhanced CT performed as part of the same evaluation were included in this study. This review yielded 30 patients. Virtual unenhanced CT images were derived from the dual-energy dataset and compared with the true unenhanced CT images by two separate radiologists who assessed the total number of calculi encountered, their location, the largest dimension, and the attenuation of the calculi. The radiation burden incurred for true unenhanced CT and virtual unenhanced CT and the total radiation burden were calculated. RESULTS. Our analysis revealed that measurements of stone size showed good interobserver agreement. The mean stone size was 7.9 ± 5.9 (SD) mm on virtual unenhanced CT and 8.4 ± 5.9 mm on true unenhanced CT (range, 2.0-31.8 mm); the difference was statistically insignificant. The mean stone attenuation differed considerably (p < 0.01) between the virtual and true unenhanced CT images (494.8 ± 187.5 HU and 924.4 ± 374.9 HU, respectively), but correlated well. The mean radiation dose for a dual-phase IV contrast-enhanced CT study was 23.13 mGy (volume CT dose index). The mean dose was 10.93 mGy for the true unenhanced CT phase, thereby suggesting a 47.25% reduction in administered radiation dose when a single-phase contrast-enhanced CT study with virtual unenhanced image reconstructions is performed. CONCLUSION. Virtual unenhanced CT images derived from dual-source dual-energy CT scans of the neck provide accurate assessment of sialolithiasis akin to that provided by conventional CT protocols but at only a fraction of the radiation dosage.

Transoral Ultrasound in the Diagnosis of Obstructive Salivary Gland Pathologies

Transcutaneous ultrasound (TCUS) is an accepted diagnostic method in salivary gland diseases. However, sparse data are available on the use of transoral ultrasound (TOUS) in sialadenopathies. One hundred five patients presenting with various obstructive sialadenopathies were examined using TOUS and TCUS. Ultrasound findings were validated by direct visualization in subsequent sialendoscopy examinations. By TOUS, but not by TCUS, all patients with sialolithiasis (70/105) could be identified and virtually all concrements, even very small ones, were detected and distinguished from artifacts. Ductal stenoses (16/105) could be correctly differentiated from sialoliths, and exceptional insights into the delicate anatomy of parotid duct stenoses were gained. TOUS provided detailed information on other space-occupying lesions (14/105) and circumvented the method-related diagnostic weaknesses of TCUS. As a valuable tool in the diagnosis of obstructive sialadenopathies, TOUS seems superior to TCUS in pathologies involving the distal parotid duct, the submandibular duct system and the floor of the mouth.

Sulfamates in drug design and discovery: Pre-clinical and clinical investigations

In the present article, we reviewed the sulfamate-containing compounds reported as bioactive molecules. The possible molecular targets of sulfamate derivatives include steroid sulfatase enzyme, carbonic anhydrases, acyl transferase, and others. Sulfamate derivatives can help treat hormone-dependent tumors including breast, prostate, and endometrial cancers, Binge eating disorder, migraine, glaucoma, weight loss, and epilepsy. Sulfamate derivatives can act also as calcium sensing receptor agonists and can aid in osteoporosis. Furthermore, acyl sulfamate derivatives can act as antibacterial agents against Gram-positive bacteria. A recent study revealed a new side effect of topiramate, a sulfamate-containing compound, which is sialolithiasis. The structural and biological characteristics of the reviewed compounds are presented in detail.

Association between cholelithiasis and sialolithiasis: Two longitudinal follow-up studies

This study aimed to evaluate the association between cholelithiasis and sialolithiasis using a national sample cohort in Korea.The Korean National Health Insurance Service-National Sample Cohort (patients ≥20 years old) was collected from 2002 to 2013. In study I, we extracted cholelithiasis patients (n = 21,170) and 1:4 matched control I subjects (n = 84,680) and analyzed the occurrence of sialolithiasis. In study II, we extracted sialolithiasis patients (n = 761) and 1:4 matched control II subjects (n = 3044) and analyzed the occurrence of cholelithiasis. Hazard ratios (HRs) were determined using the stratified Cox proportional hazard model.The HR for sialolithiasis was 1.49 (95% CI = 0.88-2.52) in the cholelithiasis group (P = .14), and the HR for cholelithiasis was 1.18 (95% CI = 0.53-2.59) in the sialolithiasis group (P = .69).We did not find an association between cholelithiasis and sialolithiasis.

Management of anterior submandibular sialolithiasis

Introduction: Sialolithiasis is defined by the presence of a calculus within the salivary gland or its excretory system. It primarily affects the submandibular gland at a frequency of 80%. Involving many factors, the exact aetiology and pathogenesis of salivary calculi remain to be discussed. Body: The purpose of this article is to expose the different aspects of the pathology. Aetiological factors, the diagnostic approach which requires the use of imaging tests as well as the medical and surgical management of anterior submandibular sialolithiasis, will be described. A decision tree regarding the type of management and a table summarizing the main differential diagnoses will be proposed. Conclusion: Submandibular sialolithiases are a common salivary gland disorder. The treatment of sialolithiasis must be early and remains mainly surgical. The level of cooperation as well as the patient's medical and surgical history should guide the management of this type of disorder of the salivary system.

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.

Chronic sialadenitis with sialolithiasis associated with parapharyngeal fistula and tonsillolith

Sialolithiasis is a common salivary pathology, suggested to affect over 1% of the population by postmortem studies. An uncommon complication of sialadenitis and sialolithiasis is the formation of fistulous tracts to other cervicofacial compartments. Submandibular gland sialocutaneous and sialo-oral fistulae have been sparsely described, but a sialo-pharyngeal fistula manifesting as a tonsillolith has yet to be described. We present an unusual case of a 35-year-old male presenting with recalcitrant neck pain and a presumed tonsillolith in the background of chronic submandibular sialadenitis, subsequently demonstrating a salivary fistula through the parapharyngeal space. We offer a thorough review of the literature to highlight the possibility of migratory sialolithiasis and its complications.