Management of Deep Caries PDF

Management of deep caries caries Dental is a progressive irreversible disease of the calcified tissues of the teeth, characterized by demineralization of the inorganic component and destruction of the organic substance. Management of a deep carious lesion may constitute areal challenge for the ski...

Management of deep caries caries Dental is a progressive irreversible disease of the calcified tissues of the teeth, characterized by demineralization of the inorganic component and destruction of the organic substance. Management of a deep carious lesion may constitute areal challenge for the skill, knowledge, experience, armamentarium and professional capabilities of the operator. He has to provide the proper pulp protection, retention and resistance forms and esthetic needs for the affected tooth. The irritation of carious process results from three distinct causes: · -Biological irritation from bacteria and their toxins. - Chemical irritation from acids. -Physico-mechanical irritation resulting from the gradual diminution of the effective dentine bridge due to the advancing carious process. Factors guiding the reaction of the pulpo-dentinal to carious process: organ 1) Type of decay: Acute carious process involves rapid and strong irritation which does not give a chance for recovery. The demineralized discolored dentin has a light yellow/yellow appearance due to rapid acid infusion with no enough time for staining by the chromogenic bacteria, the surface texture has a wet/moist appearance, and it is usually very soft during excavation and comes out in large flakes. Care should be taken to avoid pulp exposure by following a direction parallel to the pulp during excavation. chronic decay is usually accompanied by substantial repair i.e. periods of activity where the irritation increases and destructive changes occur and other periods of rest where the defensive and reparative mechanisms take part and reparative dentine will be formed. It is dark brown in color due to action of chromogenic bacteria with dry texture while arrested caries (caries that is remineralized in the rest period) is darker in color. The darkest area of the demineralized dentin indicates the oldest part of the caries lesion 2) Duration of the decay process: Acute decay (rapidly progressing caries) causes rapid destruction of the tooth structure, the longer the acute lesion remains untreated, the more the effects on the pulpo-dentinal organ expected, acute carious process very destructive to the tooth and rapidly inducing pulp exposure. In chronic decay, the longer the duration of the process, the greater the chances for repair, provided that the pulp tissue is not directly involved. 3) Depth of involvement: the deeper is the carious process, the greater the intensity of irritation and the greater the possibility for pulpal destruction. Deeper involvement causes the sources of irritation to be nearer to the pulp and makes it deprived from an effective protection barrier. The effective depth is the dentine bridge thickness along the course of the dentinal tubules. It is termed so because it expresses the length of the pathway of irritants to the pulp. When we have an effective depth in the P-D organ of 2mm or more, we can expect a healthy reparative reaction, When the effective depth is from 0.8 to 2mm, we expect an unhealthy reparative reaction. When the effective depth is less than a 0.3-0.8mm range, we can expect pulpal involvement. 4) Number and pathogenicity of micro-organisms: The number and pathogenicity of micro-organisms invading dentine determines to a great extent the activity of the lesion in terms of acuteness or chronicity. Further more, the type and metabolic activities of the bacteria in the carious lesion with the surrounding oral environment affects the rate of dentine demineralization and proteolysis. 5) Tooth dentinal resistance: The resistance of the hard dentine to spread of decay 6) The individual reaction of the pulp-dentine organ: The ability of the tissues to defend the carious process differs from case to another even to the same type and extent of the carious lesion. This is primarily due to the individual variations which are related to · The differences in the age and the general health of the patient. · The cellularity and vascularity of the pulpal tissues and its immune response. · The structural and periapical condition of the affected tooth. This makes the process of standardization of the reaction of the pulp- dentine organ to decay a difficult procedure due to the lack of precise correlation between the irritant cause and its tissue effects. This is called lack of a cause-effect relationship. Management of deep caries approximating the pulp and causing extensive tooth destruction is confronted and complicated with many problems. The success of management and the prognosis of the case is greatly dependent on the understanding and correct handling of these problems. Difficulty in determination of the exact pulpal state: Success of the vital pulp therapy depends greatly on the proper diagnosis and estimation of the prognosis of the pulp condition as there is absolutely no reliable correlation between symptomatic data.and histopathologic findings of the pulp dentin organ. In order to conduct a proper diagnosis of the pulp condition and extension of the carious lesion, several evaluating terms are employed to form the complete picture of the P-D organ and reaching the correct line of treatment by proper diagnosis using. 1) The history of pain: · Presence or absence of pain. The absence of pain in a tooth can not be used as a deciding criterion for the status of the pulp. · Incidence of pain. (sudden/intermittent/ continuous). · Type of stimulus provoking pain. (hot/cold/ pain on biting/ without stimulus) · Duration (How long does it remain?) · Severity (mild/moderate/severe). 2) Pulp sensitivity and vitality testing A) Thermal pulp testing : by the application of cold or hot is helpful in determining the pulp sensation state. b) Electric pulp testing: It is one of the most accurate methods. It detects nerve sensations of the pulp. c) Pulse Oximetry: The pulse oximeter is a non-invasive device measuring pulpal blood oxygen saturation. It is effective and reliable method giving objective results. Also useful in testing traumatized teeth. d)Laser Doppler Flowmetry: (LDF) is a non invasive, electro optical technique. It measures blood flow even in the very small blood vessels of the micro vasculature. 3) Presence of Pulp exposure: The presence of pulp exposure during excavation of carious lesion usually indicates that the progression of the lesion has been faster than the rate of pulp-dentine reaction, however, many exposed pulps are capable of performing reparative healthy reactions. This depends on the extent of perforation and the conditions at which this perforation had occurred. · Carious pulp exposures with soft dentine surrounding and increased hemorrhage are indicative of advanced pulpal inflammation. · Non-painful exposures without ooze of blood in deeply seated caries are usually indicative of loss of pulp vitality or advanced degeneration. Also exposures with foul odor and pus coming out is an indication of putrificaction of gases with definite pulp destruction and may be an accompanied with periapical involvement. · On the other hand, the presence of a pin-point exposure with surrounding sound hard dentine and pin point hemorrhage is an indication of mild to moderate pulp involvement with possibility of retained reparative ability. The inflammatory changes in such case, if present, are most likely restricted to the site of exposure or circumscribed in its close proximity and the correct management can elicit the required reparative reaction. 4) Percussion test: Tenderness of tooth to percussion is of little value in the determination of the pulpal state, however, in cases of extensive inflammation of the pulp with periapical involvement, as in cases of irreversible pulp it is with apical periodontitis, the sensitivity to percussion be comes severe. This indicates that radical forms of treatment should be carried out. 5) Radiograph: The radiograph is of little value indetecting the pulpal status. Clinical management of deep carious lesions The treatment of deep carious lesions approximating healthy pulp meaning that the patient doesn’t show any signs or symptoms of irreversible pulpitis or non-vital pulp is very challenging to the practitioner. The classical way of management was to remove all carious dentin leaving hard sound dentin (extention for prevention ).But this technique is very radical and invasive especially when dealing with very deep carious lesions due to increased risks of over preparing the tooth with subsequent increased risks of pulp exposure. Now we are going for conservative dentistry · Not all carious dentin is infected with cariogenic micro organisms it consists of outer carious infected dentin (soft brownish filled of micro organisms) and inner carious affected dentin (soft yellowish, microbial sterile). But it is not clinically easy to precisely discriminate the border line between them to stop at even with use of the caries detector dyes. · Also when dealing with very deep carious dentin (deeper than 2mm from the DEJ), it is not mandatory to remove all soft carious dentin, “any left dentin even if it is infected at the base of restorations did not continue to progress nor contribute significantly to the failure of the coronal restorations, as long as a good peripheral seal was established and maintained”. Now we are going for conservative dentistry · This good peripheral seal is very crucial for the long-term success as it deprives the bacteria from the nutrients thus causing reshifting of their metabolic and ecological balance leading to arresting their growth and activity. This helps in arresting caries and enhancing remineralization of the dentin. There are two protocols suggested for applying the incomplete caries removal for deep lesions: a) Step wise (two – step) excavation: First step (visit): After confirming the pulp state health. Complete caries and undermined enamel removal from the peripheries and walls of the cavity is done then a gross mass of soft infected dentin by a sharp hand excavator in a direction parallel to the recessional lines of the pulp is excavated leaving what is close to the pulpal floor. The tooth is sealed by a provisional restoration (e.g. glass ionomer) and followed up for several months (at least 3 months) to allow for remineralization and development of tertiary dentin. Ø N.B. when a thin layer is left and a medicament liner (e.g. calcium hydroxide or mineral trioxide aggregate MTA) is put lining the caries, this technique can be called indirect pulp capping. There are two protocols suggested for applying the incomplete caries removal for deep lesions : Second step: Re-entry visit to completely excavate the residual caries which will be harder and drier, after confirming the pulp condition by pulp vitality tests and the laid down dentin bridge by the radiograph then sealing the cavity by a final restoration. b) Partial caries removal (one step) technique: It omits the re-entry visit by sealing the tooth with a final restoration in the same visit [e.g. resin composite restoration without a base or liner, providing that doing a reliable strict bonding procedures]. The one step technique reported a higher clinical success rate compared to the two – step technique because pulp exposure may occur in the second visit during caries removal. Direct Pulp capping: is the procedure of lining the exposure site with a medicament liner (e.g. calcium hydroxide or MTA) and sealing the cavity by a well- sealed restoration to stimulate formation of the reparative dentin bridge with subsequent follow up period. Pulp exposure during the cavity preparation can occur either pathologic (from caries progression) or traumatic (due to over preparing the cavity). There is also what called micro scopic pulp exposure where frank exposure site is not seen but the size and number of open dentinal tubules are such that communication with the pulp is relative to that of a true pulp exposure, this occurs when the residual dentin bridge is less than 0.5 mm. The tooth can be considered a candidate for direct pulp capping provided that: 1. There are no signs or symptoms of degeneration in the P-D organ and there is sufficient evidence of reasonable reparative capacity. 2. The field of operation is completely aseptic preferred to be isolated by a rubber dam. Direct Pulp capping: 3. The exposure has to have following characteristics: ·.The exposure is pin-point in size or has a small diameter relative to the pulp size. · There is either no observable hemorrhage from the exposure site, or, if there is hemorrhage, the blood immediately coagulates in the form of a small button at the exposure site. · The dentin at the periphery is reparable as verified by different visual and tactile test. · The exposure site is not at a constricted or potentially constricting area in the pulp chamber or root canal system. · Traumatic pulp exposures have more predictable outcome over pathologic exposure due to less predicted bacterial invasion and pulp inflammation Direct Pulp capping: The procedures are as follows: ·.All previously described data regarding the physiologic status of the P-Dorgan should be collected and recorded. · All undesirable and/or undermined enamel and unsound dentin should be removed. · The cavity floor and exposure site should be gently washed and irrigated with sterile water. Drying should be done with sterile cotton pellets, not an air spray. · Either calcium hydroxide or MTA can be used as a capping material, though MTA showed a more successful outcome than calcium hydroxide in direct pulp capping, but Calcium hydroxide remains the Direct Pulp capping: “gold standard” for direct pulp capping. It has the longest track record of clinical success. · The permanent restoration should then be placed and the patient should be informed of the signs and symptoms of pulpal degeneration and advised to report if any are experienced. to summarize: these general considerations in prognosis of management of deep caries should be noted: The pulp can be damaged only by bacterial contamination. The restorative materials must provide a tight seal for success of the capping procedure. The basic idea for treating deep caries is to enhance calcific reparative capacity and to prevent further irritation. This could be accomplished by the following: Minimal traumatic procedure Proper capping procedure. Proper sealing of the permanent restoration. Periodic follow-up.