Definition- sialolithiasis is a pathological condition, characterized by the presence of one or more calcified stones (sialliths) within the salivary gland itself or within its duct.
The exact mechanism of formation of sialolith is not known. It is generally believed that initially a small and soft nidus forms within the salivary glands or its ducts due to some known reasons.
The nidus is made up of mucin, protiene acteria and desquamated epithelial cells.
Once a small nidus frms, it allows concentric lamellar crystallizations to occur due to the precipitation of calcium salts.
The sialolith increases in size with time as layer after layer o salts become deposited , just like growth rings in a tree.
Small sialoliths can be expelled in the mouth with the salivary secretions but bigger sialoliths continue to expand until a duct is completely closed.
It is important to note that the formation of sialolith is more common in relation to the submandibular gland and it’s duct.
Age- Sialolithiasis usually occurs among the middle aged adults, however, some cases are reported in children.
Sex- There is slight male predominance.
Sites- 70% in submandibular salivary gland and its ducts. Parotid gland is next
- In many cases sialoliths do not produce any symptoms and are detected only on routine radiographic examination.
- Chief complain ; intermittent pain, recurrent sumbandibular swelling, discomfort during meals.
- Pain is drawing or stinging in mild cases but stabing and sharp in severe cases.
- Stone in the duct can be palpated by bimanual palpation with both the fingers.
- During examination the flow and clearness of the saliva should be checked.
- Persistent swelling of the duct due to chronic obstruction by the sialolith eventually leads to chronic sclerosing sialadenitis.
- Multiple stone or bilateral cases of sialolithiasis can also be seen.
- Formation of fistulas, sinus tract, ulcerations in the area may develop in chronic cases.
- Necrosis of gland acini and lobular fibrosis may occur which results in complete loss of secretion from the gland.
- Parotid stones often cause firm swelling over the ramus of the mandible, the swelling over the ramus of the mandible, the swelling also increases during meals.
How Sialolithiasis is diagnosed
- Radilography of sialolithiasis
- Submandibular sialolithiasis are easily detected by mandibular standard occlusal radiograohs which typically disclose the presence of calcification in the floor of the mouth.
- Whn a sialolith is located in submandibular gland area then a lateral jaw radiograph will be helpful in location the exact position of the stone.
- Panaromic radiographs usually detect the parotid gland stones.
- If only branches of the submandibular gland duct are affected a posterior occlusal film submento vertex and some time a lateral jaw film may be required.
Sialography of sialolithiasis
- Sialogrohy refers to the method by which detection of salivary stones within the glad or its duct is done by giving a retrograde injection of a radiopaque dye within the duct system and obtaining a radiograph thereafter in order to see the size and distribution of the sialolith.
- Ultrasonograhy and CTscan
- These are also excellent non invasive technique useful in detecting the sialoliths
- On gross examination, sialoliths appear as round or oval rough or smooth solid masses, which vary considerably in their size.
- These stones are heavily calcified and are often multi nodular although some stones are found in small aggregates.
- The color of the stone is usually yellowish or yellowish white.