1	REACTIVE SALIVARY GLAND DISEASES Mucocele Mucus Retension Cyst Sialolithiasis Chronic sclerosing sialadenitis Necrotizing sialometaplasia
2	REACTIVE LESIONS Salivary glands react to injury or obstruction by under going atrophic degeneration and necrosis with replacement of the parenchyma by inflammatory cells and ultimately fibrous scar formation
3	Mucocele It is a tissue swelling composed of pooled mucus that escapes into the connective tissue from several excretory ducts
4	Mucocele When salivary duct is severed the acinar cells will continue to secrete saliva into the severed duct. At the site of the cut/severance the secretory product escape into the connective tissue forming a pool of mucus that distends the surrounding tissue.
5	Mucocele
6	Mucocele ETIOLOGY: Minor glands of the lip are most prone to severance as a result of injury or biting the mucosa. Intra oral minor salivary can also be effected as result of some irritation as well.
7	Mucocele CLINICAL FEATURES Mostly encountered in children and young adults. Two third of the mucoceles occur in the 3^rd decade of life. Both males and females are effected equally. SITE: mucosal surface of the lower lip buccal mucosa floor the mouth ventral of the tongue and palate Clinical appearance of the mococele depends on its location within the submucosa cont…/
8	Mucocele CLINICAL FEATURES/cont… More superficial zones of mucous extravasations presents a fluctuant mass with bluish translucent appearance. Patient usually feels the mucocele and the fluctuation in its size Pain is quite rare . Initially the mucocels are well circumscribed but with repeated truma they become nodular ,more diffuse and firm on palpation. The mucoceles have finely vascularized and distended, appearance often referred to as frogs belly that’s why they are also called Ranulas When part of this ranula is deep seated in to the sumental or submandibular space then the term used is the” Plunging Ranula”
9	Mucocele
10	Mucocele
11	Mucocele DIFFERENTIAL DIAGNOSIS Mucoepidermoid carcinoma Cavernous hemangeoma (when there is hemorrhage) Blisters seen in some bullous and desqumative disease.
12	Mucocele HISTOPATHOLOGY: Underlying pool of mucin distends the sarface epithelium. The mucin is walled of by the rim of granulation tissue or in long standing cases by condensed collagen. An epithelial lining is lacking The mucinous material basophilic or acidophillic and contains neutrophils and large oval foam cells the histocytes . The base of the mucocele will reveal feeder duct. Long standing mucoceles will show acinar degeneration with fibrosis and minimal inflammation .
13	Mucocele
14	Mucocele
15	Mucocele TREATMENT: Minor salivary gland mucocele will not resolve on its own it must be surgically excised. To minimize the chances of recurrence the feeder gland should also be removed. Post surgical parasthesia might occur when the branches of the mental nerve are severed
16	Mucocele
17	Mucus retention cyst It is a swelling caused by an obstruction of a salivary gland excretory duct resulting in an epithelial lining cavity containing mucus. Mucus retention cyst is sometimes also referred as Sialocyst
18	Mucus retention cyst The mucus retention cyst is lined by epithelium and rarely occur in the major salivary gland, when they do occur they are multiple i.e. poly cystic disease of the parotid gland
19	Mucus retention cyst
20	Mucus retention cyst CLINICAL FEATURES: Encountered in adults from 3^rd -5^th decade. The lesion is painless and fluctuant and at times bluish in appearance. SITE: parotid cysts are located in the superficial lobe as fluctuant well defined mass. -with in the oral cavity the floor of the mouth is the most common place. -this is followed by the lip and the buccal mucosa
21	Mucus retention cyst HISTOPATHOLOGY: The epithelium of the cyst is stratified cuboidal or columnar duct like epithelium. The cytoplasm in the of these cells is either clear or eosinophlic and my show some features mucous differentiation 70% of these cyst are unilocular rest of the 30% have multilocular pattern.
22	Mucus retention cyst TREATMENT: Simple excision is the treatment of choice with caution of rupturing the cystic sacs. Recurrence is rare. However damage to the adjacent gland may result in a mucocele formation.
23	Sialolithiasis There is presence of one or more round or oval calcified structures in the duct of the major or minor salivary glands( salivary stones)
24	Sialolithiasis HOW THE STONE IS FORMED: It is assumed that mucin proteins and desquamated ductal epithelial cells form a small nidus on which the calcium salts are precipitated, this nidus then allows concentric lamellar crystallizations to occur and thus sialolith increases in size as a layer by layer gets deposited on it
25	Sialolithiasis
26	Sialolithiasis CLINICAL FEATURES: About 80%of sialolith effects the major salivary glands and there is more predilection for the submandibular gland. Stones are rare in children the average age is the 4^th decade with no sex preference. They are asymptomatic discovered on dental radiographs. If symptomatic the chief complains are pain and swelling . Swelling is results as there is ductal dilatation caused by the ductal blockade. The pain is described as pulling drawing or stinging.
27	Sialolithiasis
28	Sialolithiasis Investigations: Panoramic radiograph. Ultra sound imaging orsailography
29	Sialolithiasis HISTOPATHOLOGY: Stone: On gross examination most stones are yellow or white in colour. they may be round to oval - some of the stones are nodular - after decalcification the stone shows concentric rings as of the annual rings of a tree trunk -The stone is acellular and amorphous in nature and may contain microbial colonies.
30	Sialolithiasis HISTOPATHOLOGY: Ducts: the ductal lining that surrounds sialolith shows variety of reactive changes. - there is squamous and mucus cell metaplasia and changes to stratified squamous epithelium with numerous mucous goblet cells
31	Sialolithiasis TREATMENT: Many of the major salivary gland sialoliths can be removed by manipulation of the stone through major duct orifice When manipulation fails then a surgical cut is made into the main duct In triangular, or multiple stones and long standing obstructions removal of the stone and sialadenectomy is done.
32	Necrotizing Sialometaplasia It is spontaneous condition of an unknown cause usually of the palate in which large area of the surface epithelium underlying connective tissue and all the associated minor salivary glands become necrotic while the ducts under go squamous metaplasia.
33	Necrotizing Sialometaplasia CLINICAL FEATURES: Usually the location is at the junction of the hard and the soft palatebut it may also be present at tongue, retromolar pad and the nasal cavity. NSM is characterized by deep seated ulceration it is punched out With in its deep crater are the gray granular lobules which represents the necrotic minor salivary glands. It is 2-3 cm in diameter. It is asymptomatic but there may be numbness or burning pain.
34	Necrotizing Sialometaplasia
35	Necrotizing sialometaplasia HISTOPATHOLOGY: In the palatal epithelium there is no zone of ulceration which replaced by fibrin granulation tissue. The lobules of minor salivary glands undergo coagulation necrosis. There scattered neurophils and foamy histocytes present in zone of necrosis.
36	Necrotizing sialometaplasia TREATMENT: No treatment is required once the diagnosis is confirmed by histological examination . The ulcer area heals by its self with in 1-3 months.