Diseases of Pulp PDF

DISEASES OF PULP By: Dr. Mai Hafez Lecturer of Oral &Maxillofacial Pathology Faculty of Dentistry British University in Egypt  Pulp diseases Pulp definition: The dental pulp is a delicate connective tissue interspersed with tiny blood vessels, lymphatics, mye...

DISEASES OF PULP By: Dr. Mai Hafez Lecturer of Oral &Maxillofacial Pathology Faculty of Dentistry British University in Egypt  Pulp diseases Pulp definition: The dental pulp is a delicate connective tissue interspersed with tiny blood vessels, lymphatics, myelinated and unmyelinated nerves, and undifferentiated connective tissue cells. The most common pulp disease is the pulp inflammation (pulpitis). Pulp inflammation, if not treated promptly in its early stages will usually progress into periapical inflammation. Significance of pulp anatomy in inflammation: 1- Absence of collateral circulation. 2- The constricted apical foramen presents a limitation to the pulp blood supply and venous return. 3- The pulp is enclosed within a hard dentin chamber which will not allow the pulp to swell, thus edema will occur on the expense of the vascular channels leading to compression of the vessels. Hence pulp inflammation usually ends by pulp necrosis. 4- Lack of proprioceptors, making pain localization to the correct tooth a diagnostic challenge. 5- Moreover, pulps of individual teeth are not precisely represented on the sensory cortex. The pulp pain is therefore not only poorly localized, but also may be felt in any of the teeth of the upper or lower jaw of the affected side. Rarely, pain may be referred to a more distant site such as the ear. 1  6- The pulp respond normally within limited temperature range from 20 to 45 C. so too hot or too cold stimuli may cause pulp hyperemia and inflammatory pulp changes. 7- Limited regeneration power. Etiology of pulp inflammation: ❖ Living irritants: A) Bacterial: Bacteria can gain access to the pulp through: 1. Dental caries 2. Fracture of the tooth exposing the pulp 3. Blood born infection (hematogenous) in which bacteria circulating in blood may find their way to periapical areas& to the pulp where they localize and cause infection. This process is termed “ anachoresis”. 4. Through deep periodontal pocket via an accessory root canal ❖ Non-living irritants: A) Chemical: 1. Free phosphoric acid in silicate or phosphate cement 2. Arsenic resin monomer 3. Monomer in composite restoration 4. Sterilizing agent e.g.: alcohol B) Physical: i) Thermal: 1- Large metallic restoration without base (iatroodontogenic) 2- Heat evolved during cavity & crown preparation (iatroodontogenic) 3- Heat evolved during setting of some cements e.g.: acrylic resin ii) Electric: Presence of two dissimilar metals (Galvanism) 2  C) Mechanical: 1- Trauma which may lead to crushing of blood supply of pulp 2- Abrasion 3- Accidental pulp exposure (iatroodontogenic) 4- Traumatic occlusion: if a restoration isn’t in correct occlusal relationship with its opposing teeth. (iatroodontogenic) E) Aerodontalgia/Barodontalgia This is a condition in which there is toothache caused by change in barometric pressure. It most commonly affects underwater divers and pilots. The pain results from expansion of any tiny gases of air trapped beneath a filling, in any cracked tooth or beneath decayed teeth. The pain usually ceases at ground level. associated with recently filled teeth affected by hyperemia. Classification of Pulpitis: According to type of inflammation 1. Focal Reversible Pulpitis 2. Acute irreversible Pulpitis 3. Chronic irreversible Pulpitis According to extent of pulp involvement 1. Partial Pulpitis: the inflammatory process is confined to a portion of the pulp. 2. Total Pulpitis: the entire pulp is involved. According to the presence of communication between the pulp and the oral cavity 1. Closed Pulpitis: in which there is no direct communication between the pulp and the oral cavity. 2. Open Pulpitis: the pulp communicates with the oral cavity through a wide exposure area. In this condition, the pain is usually less severe than that of closed pulpitis. 3  1- Focal Reversible Pulpitis (Pulp Hyperemia) Definition Focal reversible pulpitis is the active dilation of pulpal blood vessels representing the earliest stage of pulpitis. It is regarded as a reversible condition provided that the irritant is removed before the pulp is severely damaged. Etiology Any of the previously mentioned etiologic factors. Pathogenesis: Vasodilatation of the blood vessels and increases the capillary permeability Escape the fluid exudate causing edema with increasing the blood viscosity and slow the blood flow rate Clinically The tooth is sensitive to thermal changes particularly cold application. Pain is sharp shooting. Pain disappears rapidly on removal of the stimulus. Pain cannot be localized. The tooth is more sensitive to electrical pulp tester. Microscopically Dilation of blood vessels Edema in the connective tissue (fluid exudates) No extravasation of red blood cells, no inflammatory cells Intact odontoblastic layer 4  PULP HYPEREMIA: Dilated blood vessels with intact odontoblastic layer Treatment Removal of the cause if possible. Prognosis The condition is reversible on removal of the irritant. 2- Acute irreversible Pulpitis Definition Acute pulpitis is an acute inflammation of dental pulp. Etiology The condition may follow pulp hyperemia or exacerbation of chronic pulpitis. The previously mentioned etiologic factors can cause acute pulpitis. 5 Pathogenesis Fluid exudates causes swelling of the odontoblastic nuclei due to osmotic imbalance leading to disintegration of their nuceli Hemoconcentration of blood will lead to slowing of the blood flow rate, then migration of leukocytes A great number of leukocytes become necrotic and die releasing proteolytic enzymes which dissolves the pulp tissue resulting in liquefaction and necrosis, production of pus and pulp abscess. The 1st pulp abscess commonly seen in pulp horn.( partial suppurative pulpitis) Numerous abscesses appear which finally fuse together and total liquefaction of pulp occurs and the condition is sometimes termed suppurative pulpitis. Clinically The tooth is sensitive to thermal changes particularly cold application. Then the tooth becomes more sensitive to hot application. Pain is sharp lancinating and persists for some time after removal of the stimulus. The pain is due to pressure on the irritated nerve endings by the inflammatory exudates and due to release of pain producing substances from damaged tissues. In the later stages, pain becomes spontaneous, often when the patient is trying to get to sleep. Pain cannot be localized. The tooth is more sensitive to electric pulp tester. The tooth is not sensitive to percussion. 6 Microscopically Destruction of the odontoblastic layer Dilation of blood vessels. Edema in the connective tissue. Acute inflammatory cell infiltration (polymorphonuclear leukocytes). Focal areas of tissue destruction occurs leading to the formation of pus (pulp abscess). Pus consists of necrotic cells, dead and alive polymorphs and dead and alive bacteria. Numerous abscesses appear which finally fuse together, and total liquefaction of pulp occurs and the condition is sometimes termed suppurative pulpitis. ACUTE IRREVERSIBLE ACUTE IRREVERSIBLE PULPITIS: with destructed PULPITIS: with pulp abscess odontoblastic layer Treatment Acute pulpitis has no treatment except for extraction of the tooth or removal of the pulp by endodontic treatment. 7  3- Chronic irreversible Pulpitis Definition Chronic pulpitis is a chronic inflammation of dental pulp. Etiology It may follow acute pulpitis or arises de novo. In case of de novo chronic pulpitis, the causative agents are usually of low virulence. The general etiologic factors for pulpitis can also cause chronic pulpitis. Clinically Pain is not a feature, although the patient may complain of dull ache, which is intermittent. The reaction to thermal changes and electric pulp tester is reduced. The tooth is not sensitive to percussion. Microscopically Increased fibroblastic activity and thus the pulp becomes replaced by granulation tissue, which consists of: Newly-formed proliferating capillaries Young proliferating fibroblasts Delicate collagen fibrils Chronic inflammatory cell infiltration (plasma cells& lymphocytes) The odontoblastic layer may be intact or disrupted according to the severity Treatment Same as that of acute pulpitis. 8 Types 1- Chronic closed pulpitis 2- Chronic open pulpitis a. Chronic open ulcerative pulpitis b. Chronic open hyperplastic pulpitis (pulp polyp) A. Chronic Open Ulcerative Pulpitis Definition Chronic open ulcerative pulpitis is when the pulp is exposed (no dentin roof) and the area of exposure is replaced by granulation tissue on the subsurface (base of cavity). Clinically The pain ranges from mild dull pain to pain aggravated due to food impaction within the cavity. Microscopically The lesion consists of granulation tissue with chronic inflammatory cells. Collagen fibers in bundles are formed on the surface of the pulp in an attempt to ward off the infection. Treatment Extraction of the tooth or endodontic treatment CHRONIC OPEN ULCERATIVE PULPITIS 9  B. Chronic hyperplasic pulpits (pulp polyp): Definition: Hyperplasia of chronically inflamed pulp. Etiology for pulp polyp to develop Good sheltered area for protection of the new tissue Wide apical foramen for good blood supply Wide exposure to allow the new tissue to protrude from the pulp The patient should be young for the increased proliferative power in young age Clinically Age: Children & young adults Site: Deciduous molars or the 1st permanent molar There is a large carious cavity from which a red globule protrudes. The lesion is insensitive to manipulation because it contains fewer nerve endings Differential diagnosis Should be differentiated from gingival polyp which is attached to gingival & is more sensitive to manipulation Histopathology The lesion consists of granulation tissue with chronic inflammatory cells The granulation tissue becomes epithelized later on by: 1- Desquamated epithelial cells in saliva 2- Epithelial cells during rubbing of the check with granulation tissue Treatment: Endodontic treatment or extraction of the tooth 10  Pulp polyp 4-Pulp Necrosis (Pulp Gangrene) Definition Pulp necrosis is complete death of the vital pulp tissue due to ischemia. Etiology It is the end result of untreated acute and chronic pulpitis. Clinically Cessation of all symptoms Microscopically The pulp chamber and canals appear empty or contain necrotic structureless material. 11  Focal reversible Acute pulpits Chronic pulpits pulpits (pulp hyperemia) Reversibility Reversible Irreversible Irreversible Pain initiator Cold beverages Cold then hot The reaction to thermal and not beverages, then changes is reduced spontaneous become spontaneous and lying down Type of pain Sharp shooting Sharp lancinating and Dull aching pain interferes with sleep Pain duration Few moments, Pain continue for a Pain continue after the disappear after longer period after the stimulus is removed removal of the stimulus is removed stimulus Electric pulp Tooth respond at Tooth respond at At higher level than tester lower current lower current normal Odontoblastic Intact Disrupted May be disrupted or layer intact according to the severity Radiograph Negative Negative Negative Tooth vitality Vital Vital Vital Table showing different type of pulpitis 12