Many effects, such as infectious, chemical, physical and combined contribute to origin of the dental pulp diseases. In most cases, a mixed bacterial flora enters the pulp from a carious focus through the dentine tubules. Less frequently, an infection enters the pulp retrogradely via foramen apicale (in case of deep periodontal pockets) or by the blood stream. Silica-phosphate fillings that lack bases and to the lesser extent also composite fillings may cause chemical irritation. The pulp inflammation may occur after an acute trauma or by a chronic traumatic irritation, as well.
Regressive changes of the pulp.
As a reaction of the pulp to either external or internal irritation, the true pulp stones arise from odontoblasts. Their structure is similar to the tertiary dentine. Mock pulp stones are formed by mineralizing deposits surrounding an organic core. Pulp stones may be located freely inside the pulp’s interstitium or adhere to the walls of the pulp’s chamber or a root canal. The proof of pulp stone presence is done by an X-ray examination. Clinically, pulp stones may be a cause of neuralgic pains.
The pulp hyperemia.
This change is characterized by a short and well localized pain in response to physical or chemical stimuli which diminishes after a causing effect stops. The treatment in this case is an indirect pulp capping.
Acute pulp inflammation (pulpitis acuta).
The inflammation may affect a part of the pulp (pulpitis acuta partialis) or the whole pulp (pulpitis acuta totalis). It may have a serous (pulpitis acuta serosa) or purulent (pulpitis acuta purulenta) forms. The pain at serous pulpitis is caused by an external irritation at the beginning, later it may be spontaneous. Pain is described by a patient as blunt, radiating and pulsating. At a total pulpitis, the pain is often hard to localize (possesses a neuralgic character). Treatment for a serous pulpitis: pulpotomy or extirpation of the pulp by the vital or mortal methods. The purulent form of pulpitis accompanied by formation of small abscesses inside the pulp chamber has clinical signs similar to those at serous total pulpitis. A significant anamnestic feature is a pain relief by cooling. Treatment for the purulent form: pulpotomy or extirpation of the pulp by the vital method.
Chronic pulp inflammation (pulpitis chronica) takes forms of a closed inflammation of the pulp chamber (pulpitis chronica clausa, granulomatosa, interna) or an open inflammation (pulpitis chronica aperta hypertophica, ulcerosa). Closed pulpitis often has a course without significant clinical manifestations. A diagnosis is based on an objective finding completed by an X-ray examination (e.g. a resorption of the pulp chamber or a root canal - an internal granuloma). Pulpitis chronica aperta is characterized by growing of the pulp through a cavity, its ulceration on the surface, and sometimes by an outgrowth of the granulomatous tissue through a cavity to the oral cavity and formation of the pulpous polyp. Clinical signs are mild, bleeding occurs often as a result of the pulpal tissue injury.
The treatment of the pulp altered by an inflammation is performed by its partial removal (pulpotomy) or total removal (extirpation). The pulp removal may be done under a local or block anesthesia (the vital method) or after a devitalization of the pulp by treatment of various substances (the mortal method). As devitalizers, arsenic trioxide, cobalt paste (arsenic metal), or paraformaldehyde are often utilized. Arsenic trioxide (Arsodent) is a protoplasmic poison that affects blood vessels, cells of the pulp and nerve endings. Its application results in necrosis of the pulp that can be removed painlessly. Arsodent is applied as close to the pulp as possible or directly on an exposed pulp, and a cavity is then sealed hermetically by a temporary filling. Its effect on molars lasts for 48 hours, after that it is necessary to remove the necrotic pulp, to fill the root canal by a root filling material and to make a permanent filling. Arsenic metal has the same effects as Arsodent, although its action is prolonged and is usually applied for a period of 3 to 5 days. The paraformaldehyde paste releases formaldehyde. Anesthetics that are contained in the paste relieve the pain. Since the paste is not very stable, its activity decreases with time. The mortal method is indicated for all kinds of pulp inflammation except the purulent, ulcerous and polypous forms. The use of Arsodent is contraindicated at teeth with incomplete root development. At this method, a patient has to be informed that a pain won’t disappear immediately and that a devitalizer has to be removed from a dental cavity on time. For these reasons the vital method of treatment is preferred. Requirements for a good result of the vital method are proper diagnosis of the disease, good anatomical conditions of the root canal and sufficient amount of time for the treatment. The greatest advantage of this method is completion of the whole treatment during one visit.
The consequence of inflammatory and degenerative changes of the pulp is pulp necrosis that may affect just a part or the whole pulp. If there is an infection at a necrotic pulp, the pulp gangrene occurs. A patient with gangrene feels pain during a heat test.
Category: Restorative Dentistry Notes