Post-Operative Hypersensitivity and Pain PDF

POST-OPERATIVE HYPERSENSITIVITY AND PAIN Causes of Post-Operative Sensitivity: Pre-Operative Causes: 1. Improper Diagnosis. 2. Armamentarium Contamination. Intra-Operative Causes: 3. Cavity Preparation 4. Improper Isolation 5. Material Manipulation a. Direct Resin Composite b. Amal...

POST-OPERATIVE HYPERSENSITIVITY AND PAIN Causes of Post-Operative Sensitivity: Pre-Operative Causes: 1. Improper Diagnosis. 2. Armamentarium Contamination. Intra-Operative Causes: 3. Cavity Preparation 4. Improper Isolation 5. Material Manipulation a. Direct Resin Composite b. Amalgam Restorations Causes of Post-Operative Sensitivity: Post-Operative Causes: 6. Finishing and Polishing. 7. Faulty Occlusal and Proximal Contacts Relationships. Pre-Operative Causes: :1- Improper Diagnosis It is extremely important to establish a precise diagnosis before any restorative procedure, in order to be certain that the pain reported by the patient does not originate from pre-existing causes, such as tooth fractures, dentinal sensitivity as a result of dentin exposure in the cervical region, or reversible or irreversible pulp condition. Pre-Operative Causes: :2- Handpiece Contamination Elevated numbers of oral streptococci and.staphylo - coccus aurous. These contaminations may affect the: pulp health and lead to post-operative sensitivity. Proper sterilization of used handpiece as well as regular monitoring of microbial contamination of dental unit waterlines are necessary to provide superior dental treatment and prevent cross-infection and post-operative sensitivity Intra-Operative Causes: 3- Cavity Preparation: Post-operative pain of dentinal origin is intimately related to intra-operative procedures, and may occur by cutting and exposing healthy dentin, due to dentin dehydration, or due to the improper application of dental cutting instruments during cavity preparation. Intra-Operative Causes: The use of burs and diamond stones with excessive cutting pressure, without the use of adequate cooling, may generate frictional heat and dentin dehydration. Even if this happens for only a short time, it causes displacement of the tubular fluid and a painful pulp response. Dull burs and diamond stones require greater pressure during cavity preparation, leading to a rise in temperature. A previous study has concluded that diamond burs must be replaced after fourth preparation, and their use after the fifth preparation is questionable. Intra-Operative Causes: Therefore, these types of damage post-operative pain can be avoided by the use of new burs and diamond stones, adequate cooling, and cutting with intermittent pressure-free movements. Intra-Operative Causes: :4- Improper Isolation Absolute isolation is indicated to reduce two issues that cause postoperative sensitivity caused by penetration of saliva into the operative field: 1) contamination of the cavity by microorganisms that cause pulp inflammation. 2) contamination by humidity, which harms the material’s bonding and facilitates marginal leakage. Intra-Operative Causes: A study showed that the type of isolation has no influence on the occurrence of post-operative pain. Therefore, the key is to avoid contaminants from leaking into the cavity prep by any means available. Intra-Operative Causes: 5- Material Manipulation: A) Direct Resin Composite Post-operative Sensitivity: to understand the reasons for resin composites post-operative sensitivity, it is natural to focus on the bonding procedures. Intra-Operative Causes: Etching: The Type of etchant, concentration, etching time, and tissue to be etched all are factors must be considered during etching procedure to prepare dental tissue for hybridization. An increased dentin etching time is another clinical error responsible for the occurrence of post-operative sensitivity; due to dehydration and therefore must be avoided. Intra-Operative Causes: Bonding (hybridization) Dentin hybridization is a process that creates a mixed layer of resin monomers and collagen fibrils, altering the physical and chemical properties of this tissue. The formation of bond interfaces that is as perfect as possible and minimizes or prevents the entry of bacterial fluids is important to guarantee greater longevity of resin composite restorations. Inadequate hybridization results in marginal leakage, resin discoloration, and post-operative sensitivity. Intra-Operative Causes: Therefore, dentin hybridization and steps of application of the adhesive systems must be meticulously performed to decrease or even prevent post operative sensitivty. Intra-Operative Causes: Resin Composite Polymerization Polymerization Shrinkage The resin develops forces that may cause rupture of the bond between the adhesive system and cavity forming microscopic gaps at the tooth/restoration interface. These gaps allow entry of bacteria, and may lead to the formation of caries, stains and post-operative sensitivity. To reduce the effect of polymerization shrinkage, the application of resin in small increments and the use of a base material with a low modulus of elasticity; i.e. flowable composites or glass ionomers, are some suggestions. Intra-Operative Causes: Incomplete Polymerization Incomplete resin composite polymerization is also responsible for postoperative sensitivity. Intra-Operative Causes: B-Amalgam Restorations Post-operative Sensitivity: Inadequately lined restoration: Amalgam; as all metallic restorations, conduct thermal changes to underlying dentin-pulp complex which often causes post- operative pain; especially in deep cavities. Post-operative sensitivity may be minimized with the use of protective lining materials that will act on the dentin-pulp complex. Intra-Operative Causes: :Galvanism Galvanism occurs when two dissimilar metal alloys with different electromotive forces are placed in the oral cavity. When two dissimilar metallic restorations opposing each other come into contact the current is suddenly short circuited, most probably through one of the two teeth causing pain. Intra-Operative Causes: Many factors affect galvanic activity: a) The difference in electrode potential for dissimilar metals. b) the electrical resistance of the dentin and soft Tissues. c) the current density. d) whether or not the pulp is in a state of hyperalgesia; due to inflammation and presence of algogenic substance which cause an increase in pulp sensitivity. Post-Operative Causes: 6- Restoration finishing and polishing: Restorations must be built in a way that finishing and polishing steps are restricted to small adjustments in the shape and superficial polishing. Purposely inserting a large excess of material and then performing finishing is extremely unfavorable to the tooth and the restoration. The exaggerated frictional heat generated by the high speed bur increases the possibility of pulp injury and subsequent post-operative sensitivity. Post-Operative Causes: The careful use of burs and abrasive instruments at this stage prevents possible damage to the restoration margins and adjacent dental tissue; especially during finishing of cervical margins and subsequent loss of cementum, thus avoids the risk of post-operative sensitivity. Post-Operative Causes: :7- Faulty Occlusal and Proximal relationships Improper adjustment of the occlusal interface of the new restorations may lead to dimensional changes that could cause fluid movement within the dentinal tubules and lead to post- operative pain. Teeth will often be sensitive to biting pressure as well as to hot and cold. This can be easily avoided by proper evaluation and removal of any occlusal interferences and high spots.