[A PhD completed. More insight into the origin and composition of salivary stones]. / Serie: Hora est. Meer inzicht in het ontstaan en de samenstelling van speekselstenen.

Salivary stones are hardened, stony calcifications that primarily develop in the drainage duct of a salivary gland. They can lead to obstruction of the saliva flow, resulting in swelling and pain. Since the aetiology of salivary stones remains largely unclear, this was further investigated in this PhD study. A case-control review of patient records showed that systemic diseases and lifestyle factors most likely do not play a role in their occurrence. The biochemical composition of salivary stones removed by oral-maxillofacial surgeons was examined, revealing that large salivary stones have a different inorganic composition than small salivary stones. Several salivary proteins were detected in submandibular salivary stones, including lysozyme, s-IgA, and -amylase. Clumping together of these proteins may play a role in the initial formation of salivary stones.

Comparative analysis of approaches to the Wharton's duct during surgery of the submandibular gland: A retrospective case-control study.

INTRODUCTION: We investigated complications and recurrence rates after surgical techniques for sialolith removal with intact and resected Wharton's duct of the submandibular gland. METHODS: The retrospective case-control analysis of a series analysed 271 surgical operations (2003-2022) for sialolithiasis performed at a hospital department of Otolaryngology-Head and Neck Surgery. The study compared two approaches: (1) pure endoscopic technique or pinpoint stone removal with Wharton's duct left intact and (2) transoral duct dissection or pinpoint stone removal technique, after which the duct was shortened. While choosing the surgical option, the size of the stone, the location of the stone, and the presence of multiple stones were taken into account. The rates of complications (lingual nerve paraesthesia, duct stenosis, drooling, and sialoadenitis), the incidence of foreign bodies, and the rate of recurrence during follow-up of ≥18 months were compared. RESULTS: 323 sialoliths were removed from 271 patients. Of these 323 calculi, 150 were removed by the first approach and 173 by the second approach. The calculi varied in diameter from 2 to 38 mm with an average diameter of 8.2 mm. For all 271 patients, the rate of recurrence was 4.8%, but 11 recurrent cases (8.7%) appeared after the first approach surgeries and 2 cases (1.4%) after the second approach surgeries (p = .03). Other variables did not show statistically significant differences. CONCLUSIONS: Surgical removal of the submandibular calculi, ending with shortening of Wharton's duct, reduces the recurrence rate for sialolithiasis but does not affect the rate of postsurgical complications.

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.

Partial facial paralysis induced by sialolithiasis of the parotid gland: a case report.

BACKGROUND: Facial paralysis due to parotid sialolithiasis-induced parotitis is a unusual clinical phenomenon that has not been reported in prior literature. This scenario can present a diagnostic challenge due to its rarity and complex symptomatology, particularly if a patient has other potential contributing factors such as facial trauma or bilateral forehead botox injections as in this patient. This case report elucidates such a complex presentation, aiming to increase awareness and promote timely recognition among clinicians. CASE PRESENTATION: A 56-year-old male, with a medical history significant for hyperlipidemia, recurrent parotitis secondary to parotid sialolithiasis, and recent bilateral forehead cosmetic Botox injections presented to the emergency department with right lower facial drooping. This onset was about an hour after waking up and was of 4 h duration. The patient also had a history of a recent ground level fall four days prior that resulted in facial trauma to his right eyebrow without any evident neurological deficits in the region of the injury. A thorough neurological exam revealed sensory and motor deficits across the entirety of the right face, indicating a potential lesion affecting the buccal and marginal mandibular branches of the facial nerve (CN VII). Several differential diagnoses were considered for the lower motor neuron lesion, including soft tissue trauma or swelling from the recent fall, compression due to the known parotid stone, stroke, and complex migraines. An MRI of the brain was conducted to rule out a stroke, with no significant findings. A subsequent CT scan of the neck revealed an obstructed and dilated right Stensen's duct with a noticeably larger and anteriorly displaced sialolith and evidence of parotid gland inflammation. A final diagnosis of facial palsy due to parotitis secondary to sialolithiasis was made. The patient was discharged and later scheduled for a procedure to remove the sialolith which resolved his facial paralysis. CONCLUSIONS: This case emphasizes the need for a comprehensive approach to the differential diagnosis in presentations of facial palsy. It underscores the potential involvement of parotid sialolithiasis, particularly in patients with a history of recurrent parotitis or facial trauma. Prompt recognition of such uncommon presentations can prevent undue interventions, aid in timely appropriate management, and significantly contribute to the patient's recovery and prevention of long-term complications.

Removal of intraglandular calculi in Wharton's duct: clinical outcome and treatment algorithm.

The aim of this study was to propose a treatment strategy for intraglandular submandibular calculi based on calculus site. Seventy-three consecutive patients with impalpable intraglandular submandibular calculi were enrolled retrospectively. The calculi were classified as either post-hilar type, central type, or superficial type. Treatment approaches included transoral duct slitting (TDS), interventional basket retrieval (IBR), intraductal laser lithotripsy (ILL), and transcervical lithotomy (TCL). Complete calculus removal with gland preservation was achieved in 64 patients (87.7%). The success rate for post-hilar, central, and superficial calculi was 86.4% (51/59), 90.9% (10/11), and 100% (3/3), respectively. The treatment approach applied in patients with treatment success was TDS in 32 cases, IBR in 20, ILL in nine, and TCL in three. During follow-up (median 17.3 months), one patient experienced gland atrophy and three had ductal stenosis; the remaining 60 patients (93.8%, 60/64) had good clinical outcomes. In the eight failure cases operated by TDS, the deeply situated calculi could not be detached despite the parenchymal incision in five cases, while the procedure was ceased due to the patient's inability to cooperate in the other three cases. In the remaining failure case, the submandibular gland was sacrificed after calculus extraction via TCL. Application of the proposed treatment algorithm might help preserve gland function in patients with intraglandular submandibular calculi.

Salivary Mucinous Adenocarcinoma Masquerading as Chronic Submandibular Sialolithiasis.

A patient with chronic submandibular sialolithiasis underwent conservative treatment with appropriate imaging and multiple biopsies that continually revealed chronic inflammation. Due to continued symptoms, the patient underwent eventual excision and finaly pathology revealed salivary mucinous adenocarcinoma, which is a rare and poorly understood salivary malignancy. Persistent diagnostic workup and a high suspicion for salivary gland lesions is important for appropriate diagnosis and treatment. More attention and research on this specific entity can help future clinicians better diagnose and treat patients with a similar presentation. Laryngoscope, 134:2258-2261, 2024.

Intraoral Microscopic Versus Robot-Assisted Sialolithotomy and Sialendoscopy for Submandibular Stones.

OBJECTIVE: Sialendoscopy has remained the standard of treatment for sialolithiasis; however, large stones impacted in the submandibular gland hilum often require an intra-oral combined approach. METHODS: Patients treated for submandibular hilar sialolithiasis from 2015 to 2021 at two tertiary centers were stratified into two groups based on the surgical technique: Intraoral Microscopic-Assisted Sialolithotomy (IMAS) versus Robot-Assisted Sialolithotomy and Sialendoscopy (RASS). We compared the characteristics of retrieved stones, surgical success rate, operative time, and post-operative complications in both techniques. True surgical success was defined as successful stone extraction without reoccurrence within 12 months. RESULTS: The RASS technique was attempted in 60 patients and successful in 56 (93.3%) cases whereas the IMAS technique was performed in 52 patients and successful in 48 (92.3%) cases. The longest dimension of the predominant retrieved calculi was 9.6 ± 3.1 mm (range, 5-18 mm) for the robotic technique and 10 ± 4.8 mm (range, 5-30 mm) for the microscopic technique. The operative time for the robotic technique excluding robot setup time was 70.6 ± 24.8 min compared to 61.9 ± 42.4 min for microscopic technique (p = 0.018). No major adverse outcomes were reported; however, temporary lingual paresthesia was found in ten robotic (16.7%) and five microscopic (9.6%) cases. CONCLUSION: The two techniques were comparable in terms of efficacy and safety for large stones. The robot has the advantage of intraoral high dynamic maneuverability and improved surgeon posture while the microscopic technique has the advantage of intraoral tactile feedback. The procedure was significantly shorter in duration with the microscope. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:2170-2176, 2024.

Holmium:YAG laser-assisted intraductal sialendoscopic lithotripsy under local anesthesia.

OBJECTIVES: This retrospective multi-institutional chart review study aims to present results from patients treated with Holmium:YAG laser-assisted sialendoscopic intraductal lithotripsy under local anesthesia. METHODS: Preoperative ultrasound and/or CT were used for location and measurement of the stones. Local anesthesia was applied in all patients, Marchal all-in- one 1.3 mm and Erlangen 1.6 sialendoscopes were used. The laser was used with power settings limited by discomfort or pain. Inclusion criteria were stone size (all >5 mm) and fixed stones. RESULTS: 42 patients, 48 stones were treated (30 males/12 females), 21 submandibular and 21 parotid. Ages ranged from 20 to 70 years (95 % CI: 43.37-51.58). Mean size was 6.2 mm (95 % CI: 5.71-6.72). Complete fragmentation was achieved in 66.7 % and incomplete in 33.3 %. Out of the incomplete fragmented 14 cases, seven (50 %) remained symptom free on follow-up. Maximum duration was 120 min. Minimum power settings of the laser was 4.8 Watts and maximum 18 Watts. Six patients expressed pain or discomfort that limited power increase and duration of the procedure. Total follow up time was 10 years. There were no major complications such as hemorrhage, nerve paresis or skin ulceration. CONCLUSION: The procedure is safe under local anesthesia, well tolerated by most patients and should be used in cases of small fixed and "intermediate-sized" stones as a single modality. Discomfort may limit power settings and duration. The later is the major disadvantage of the method.

Venous malformation phleboliths mimicking submandibular sialadenitis in children.

To report one paediatric patient who presented with a rare venous vascular malformation as a mass in the left submandibular region with a clinical picture compatible with sialadenitis. Phleboliths are a specific feature of venous malformations due to venous stasis and may mimic sialoliths on various imaging modalities. Thus venous malformations are often misdiagnosed as sialadenitis due to sialolithiasis. Sialoliths are extremely rare in paediatric patients. In an early adolescent presenting with a submandibular mass and suspected sialadenitis arising from sialoliths, a detailed history, clinical examination and careful review of the radiological findings will allow the diagnosis of venous vascular malformation and provide the complete surgical resection. Our patient was initially referred with a presumed diagnosis of submandibular sialadenitis, and instead a venous malformation with phlebolith was diagnosed.

Is the neutrophil-to-lymphocyte ratio a marker for differentiating between benign and malignant submandibular gland masses?

OBJECTIVE: This study aimed to evaluate the effect of the neutrophil-to-lymphocyte ratio on the differentiation of benign and malignant masses in the submandibular triangle. METHODS: We retrospectively evaluated 48 patients who underwent surgery for submandibular gland masses between January 2013 and February 2023. The patient's age, gender, preoperative complete blood count and imaging findings, postoperative histopathological diagnosis, and hemogram data were analysed. Patients were evaluated according to their postoperative histopathological diagnoses and categorised into four main groups: sialolithiasis, sialadenitis, benign tumours, and malignant tumours. Benign submandibular gland disease formations were evaluated under group B and malignant tumour formations under group M. RESULTS: A preoperative fine needle aspiration biopsy was performed on 19 patients due to sialadenitis, pleomorphic adenoma, and malignant diseases other than sialolithiasis. One patient died among the patients with malignant disease and the remaining 7 patients were compared with the benign group of 40 patients regarding preoperative and postoperative neutrophil-to-lymphocyte ratio. In the benign group, the neutrophil-to-lymphocyte ratio was 2.64 preoperatively and decreased to 2.34 in the first postoperative year. The preoperative neutrophil-to-lymphocyte ratio decreased from 4.79 to 1.77 postoperatively in the malignant group. A statistically significant difference was observed (p<0.05). CONCLUSION: This is the first study to demonstrate that the neutrophil-to-lymphocyte ratio can be used as a biomarker in submandibular gland masses and has prognostic significance in malignant masses. In addition to fine needle aspiration biopsy results, neutrophil-to-lymphocyte ratio can be used as a biomarker.

[Lithiasic salivary gland pathologies]. / Pathologies lithiasiques des glandes salivaires.

LITHIASIC SALIVARY GLAND PATHOLOGIES. Sialolithiasis is the most frequent pathology affecting the salivary glands. Almost 80% of these lithiasis affect the submandibular gland, in the Wharton duct whilst 20% occur in the parotid gland in the Stenon duct. The diagnosis is based on typical patient interrogation and clinical symptoms (intermittent facial swelling associated with eating, sialadenitis) and/or on paraclinical examination. Ultrasound echography is often prescribed, but CT-scan and sialo-MRI offer a more precise preoperative assessment. Minimally-invasive gland-preserving techniques such as sialendoscopy (combined or not with transoral duct surgery) are nowadays considered to be the method of first choice. These methods reach success rates above 80% and significantly reduce surgical complications and hospital stay.

PATHOLOGIES LITHIASIQUES DES GLANDES SALIVAIRES. Parmi les pathologies des glandes salivaires, les lithiases des canaux salivaires sont les plus fréquentes. Elles sont le plus souvent retrouvées dans les glandes sous-maxillaires au niveau des canaux de Wharton (80 %), et plus rarement dans les glandes parotides au niveau des canaux de Sténon (20 %). Le diagnostic repose sur l'interrogatoire et la clinique, qui peuvent être évocateurs (hernie ou coliques salivaires, sialite aiguë), et sur l'imagerie. L'échographie est un examen diagnostique très accessible, mais le scanner et la sialo-IRM permettent une évaluation préopératoire plus précise. Le traitement repose en première intention sur des traitements chirurgicaux conservateurs et mini-invasifs tels que la sialendoscopie, associée ou non à une approche transorale, qui sont efficaces dans 80 % des cas et permettent de réduire les complications postopératoires et la durée d'hospitalisation.

A comparative study of three-dimensional cone-beam CT sialography and MR sialography for the detection of non-tumorous salivary pathologies.

BACKGROUND: Imaging of the salivary ductal system is relevant prior to an endoscopic or a surgical procedure. Various imaging modalities can be used for this purpose. The aim of this study was to compare the diagnostic capability of three-dimensional (3D)-cone-beam computed tomography (CBCT) sialography versus magnetic resonance (MR) sialography in non-tumorous salivary pathologies. METHODS: This prospective, monocenter, pilot study compared both imaging modalities in 46 patients (mean age 50.1 ± 14.9 years) referred for salivary symptoms. The analyses were performed by two independent radiologists and referred to identification of a salivary disease including sialolithiasis, stenosis, or dilatation (primary endpoint). The location and size of an abnormality, the last branch of division of the salivary duct that can be visualized, potential complications, and exposure parameters were also collected (secondary endpoints). RESULTS: Salivary symptoms involved both the submandibular (60.9%) and parotid (39.1%) glands. Sialolithiasis, dilatations, and stenosis were observed in 24, 25, and 9 patients, respectively, with no statistical differences observed between the two imaging modalities in terms of lesion identification (p1 = 0.66, p2 = 0.63, and p3 = 0.24, respectively). The inter-observer agreement was perfect (> 0.90) for lesion identification. MR sialography outperformed 3D-CBCT sialography for visualization of salivary stones and dilatations, as evidenced by higher positive percent agreement (sensitivity) of 0.90 [95% CI 0.70-0.98] vs. 0.82 [95% CI 0.61-0.93], and 0.84 [95% CI 0.62-0.94] vs. 0.70 [95% CI 0.49-0.84], respectively. For the identification of stenosis, the same low positive percent agreement was obtained with both procedures (0.20 [95% CI 0.01-0.62]). There was a good concordance for the location of a stone (Kappa coefficient of 0.62). Catheterization failure was observed in two patients by 3D-CBCT sialography. CONCLUSIONS: Both imaging procedures warrant being part of the diagnostic arsenal of non-tumorous salivary pathologies. However, MR sialography may be more effective than 3D-CBCT sialography for the identification of sialolithiasis and ductal dilatations. TRIAL REGISTRATION: NCT02883140.

Transoral removal of submandibular hilar lithiasis: results on the salivary duct system, glandular parenchyma, and quality-of-life recovery.

OBJECTIVE(S): To confirm that hilar transoral submandibular sialolitectomy (TOSL) is the first treatment option for submandibular hilar lithiasis (SHL) in terms of glandular parenchyma recovery, salivary system restoration, and patient quality of life (QoL) improvement. METHODS: Depending on whether the stone was easily palpable, TOSL was carried out with or without sialendoscopy. For the first time in the literature, Magnetic Resonance Sialography (MR-Si) was performed before and after TOSL, to evaluate stone characteristics, glandular parenchyma status, hilum dilation and main duct recanalization. Radiological data was examined independently by two radiologists. COSQ, a recently validated and specific questionnaire, was used to assess associated QoL. RESULTS: Between 2017 and 2022, 29 TOSL patients were examined. With a high interobserver correlation, MR-Si was confirmed as a very useful radiological test in the pre- and post-surgical evaluation of SHL. The salivary main duct was completely recanalized in all cases. The presence of lithiasis was found in 4 patients (13.8%). After surgery, the majority of patients (79.31%) had hilum dilation. There was a statistically significant improvement in parenchyma status, but no significant progression to glandular atrophy. After surgery, COSQ mean values always improved (22.5 to 4.5). CONCLUSIONS: TOSL is the ideal surgical technique for the management of SHL, resulting in improved parenchymal inflammatory changes, recanalization of Wharton's duct, and enhancement patients' QoL. As a result, before removing the submandibular gland, TOSL should be considered as the first treatment option for SHL.

Identification of biological components for sialolith formation organized in circular multi-layers.

According to the previous studies of sialolithiasis reported so far, this study is aimed to identify the biological components of sialolith, which show different ultrastructures and chemical compositions from other stones, cholelith and urolith. Twenty-two specimens obtained from 20 patients were examined histologically, and analyzed with micro-CT, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). All sialoliths (n = 22) observed in this study showed a central nidus, which was filled with organoid matrix admixed with exosome vesicles, loose calcium apatite crystals, and many bacteria. The micro-CT and SEM observation clearly defined a single or multiple central nidus(es) encircled by highly calcified compact zone. The circular compact zone showed a band-like calcification, about 1-3 mm in thickness, and usually located between the central nidus and the peripheral multilayer zone. But some sialoliths (n = 5) showed severe erosion of compact zone by expanding multilayered zone depending on the level of calcification and inflammation in sialolith. By observing TEM images, many exosome vesicles and degraded cytoplasmic organelles were found in the central nidus, and some epithelial cells were also found in the calcified matrix of peripheral multilayer zone. Particularly, EDS analysis indicated the highest Ca/P ratio in the intermediate compact zone (1.77), and followed by the central nidus area (1.39) and the peripheral multilayer zone (0.87). Taken together, these data suggest that the central nidus containing many inflammatory exosomes and degraded cytoplasmic organelles has a potential to induce a band-like calcification of compact zone, and followed by the additional multilayer deposition of exfoliated salivary epithelial cells as well as salivary materials. Thereby, the calcium apatite-based sialolith is gradually growing in its volume size, and eventually obstructs the salivary flow and provides a site for the bacterial infection.

Submandibular sialolith migration.

A middle-aged male Caucasian had rejected previous offers of surgery for submandibular gland removal in the past due to concerns about surgical complications. He presented with a month's history of submandibular swelling and severe pain, which impeded his ability to eat. Prior to admission, he had been experiencing intermittent sialadenitis for several months. Cross-sectional imaging demonstrated a 16×12 mm migratory sialolith, located superficial to the right submandibular gland within a large loculated abscess. The patient underwent an incision and drainage of the abscess under general anaesthetic and the sialolith was expressed. He was discharged home with oral antibiotics and was followed up as an outpatient. This case serves to highlight a rare complication of chronic sialolithiasis.

Sialendoscopy in treatment of obstructive sialadenitis.

OBJECTIVES: Sialendoscopy is a relatively new mini-invasive method that allows direct visualisation and intervention in the salivary gland ductal system. The aim of the study was to evaluate the results of sialendoscopy in the treatment of obstructive sialadenitis. MATERIALS AND METHODS: This is a 15-year retrospective study analysing the treatment results of patients treated in the period of 2007-2022 at the Department of Oral and Maxillofacial Surgery, Comenius University Bratislava, Slovakia. RESULTS: The total number of performed sialendoscopies was 70, of which 44 (62.9 %) were performed on the submandibular gland and 26 (37.1 %) on the parotid gland; 46 procedures (65.7 %) were performed via natural ductal system opening without the need for surgical assistance while 24 sialendoscopies (34.3 %) required surgical assistance. The most frequent perioperative findings were the sialoliths (37) in quantities ranging from one to four. Non-calculi pathologies (23) included mucous plugs, strictures, plaque, erythema or foreign bodies. No pathology was found on 10 sialendoscopies. In 82 % (n = 55) of patients, sialendoscopy prevented the salivary gland from being excised. In 18 % (n = 12) of cases, sialendoscopy findings indicated that salivary gland excision was needed. CONCLUSION: The study acknowledges the significant benefit of sialendoscopy in the treatment of obstructive sialadenitis (Tab. 3, Fig. 6, Ref. 39). Text in PDF www.elis.sk Keywords: sialendoscopy, sialadenitis, duct obstruction, sialolith, minimally invasive surgery.

A comparative study of three-dimensional cone beam computed tomographic sialography and ultrasonography in the detection of non-tumoral salivary duct diseases.

OBJECTIVES: To compare the overall diagnostic outcomes of 3D-CBCT sialography and ultrasonography (US) in the detection of sialolithiasis, ductal dilatation, and ductal stenosis. METHODS: This retrospective monocentric study compared the two imaging modalities carried out in the same patients referred for salivary symptoms of the parotid and submandibular glands. The primary endpoint was the capacity of the imaging procedure to diagnose a lesion. The secondary objectives were the detection rates according to the type of lesion, analysis of the causes of failure, and the parameters of radiation exposure and safety (for 3D-CBCT sialography). RESULTS: Of the 236 patients who received a 3D-CBCT sialography in our institution, 157 were ultimately included in the per-protocol analysis. 3D-CBCT sialography allowed detection of ductal lesions in 113 patients versus 86 with US. The two imaging modalities yielded congruent interpretations in 104 out of 157 subjects (66.2%). Higher sensitivity and negative predictive value were observed with 3D-CBCT sialography compared with US, irrespective of the lesions studied: 0.85 vs 0.65 and 0.70 vs 0.44, respectively. Regarding the sialolithiasis, both 3D-CBCT sialography and US allowed identification of lesions with high sensitivity and negative predictive value (0.80 vs 0.75 and 0.88 vs 0.78, respectively). CONCLUSIONS: US remains the first-line examination for exploration of the salivary lesions. 3D-CBCT sialography is an alternative in case of inconclusive US, and prior to any endoscopic procedure.

Ablation of TRPC3 disrupts Ca2+ signaling in salivary ductal cells and promotes sialolithiasis.

Clinical studies and structural analyses of salivary stones strongly suggest a linkage between higher saliva calcium (Ca2+) and salivary stone formation, sialolithiasis; however, the process and the mechanism leading to Ca2+ overload during sialolithiasis is not well understood. Here, we show that TRPC3 null (-/-) mice presented with a reduction in Ca2+ entry and current in ductal cells with higher saliva [Ca2+] suggesting diminished transepithelial Ca2+ flux across the salivary ductal cells, leaving more Ca2+ in ductal fluid. Significantly, we found that TRPC3 was expressed in mice and human salivary ductal cells, while intraductal stones were detected in both mice (TRPC3-/-) and patient (sialolithiasis) salivary glands. To identify the mechanism, we found that TRPC3 was crucial in preventing the expression of calcification genes (BMP2/6, Runx2) in ductal cells which may be due to higher extracellular Ca2+ in SMG tissues. Similarly, inflammatory (IL6, NLRP3), fibrotic (FN1, TGFß1) and apoptotic (Bax1/Bcl2) markers were also elevated, suggesting that the loss of TRPC3 induces genetic changes that leads to salivary gland cell death and induction of inflammatory response. Overall, ablation of TRPC3-/- leads to higher saliva [Ca2+], along with elevated detrimental gene expressions, altogether contributing to salivary gland stone formation.