Treatment of Dentin Hypersensitivity Dr. Ahmed Al Mokhatieb

is exemplified by brief, sharp, well-localized pain in response to thermal, evaporative, tactile, osmotic, or chemical stimuli that cannot be ascribed to any other form of dental defect or pathology Pulpal pain is usually more prolonged, dull, aching, and poorly localized and usually lasts longer than the applied stimulus.

Up to 30% of adults have dentin hypersensitivity at some period of their lives Current techniques for treatment may be only transient in nature and results are not always predictable

Two chief methods of treatment of dentin hypersensitivity 1 tubular occlusion 2blockage of nerve activity

A differential diagnosis needs to be accomplished before any treatment because many symptoms are common to a variety of causes

Items to be considered: the pain—sharp, dull, or throbbing how many teeth and their location which part of the tooth elicits the pain the intensity of the pain

Clinical and radiographic examination is necessary to elucidate the cause

The following questions need to be asked Can the pain be localized to one tooth or area of the tooth? Is the area sensitive to a moderate flow of air from an air water syringe? Is the tooth sensitive to percussion? Is there sensitivity to biting pressure or on release?

The following questions need to be asked What is the extent of the pain after the stimuli is removed? Do radiographs demonstrate caries or periapical pathology? Is the dentin exposed as a result of recession and are there any cracked cusps, open margins, or occlusal hyperfunction?

MECHANISM There are regional differences in dentin sensitivity Freshly exposed dentin in the coronal part of the tooth is more sensitive than cervical dentin

Hypersensitive dentin, however, is found most often in the cervical area The sensitivity of dentin has a direct correlation with the size and patency of the dentinal tubules Absi and colleagues discovered that hypersensitive teeth have an increased number of patent tubules and wider tubules than those of no sensitive teeth

CAUSES There is no principal cause. The loss of enamel and removal of cementum from the root with exposure of dentin, however, is a major contributing factor

CAUSES Causes include gingival recession due to root prominence and thin overlying mucosa, dehiscences and fenestrations, frenum pulls, and orthodontic movement, which causes a root to be moved outside its alveolar housing

Loss of enamel may be a consequence of attrition, erosion, abrasion, and abfraction. The loss of enamel, however, is usually a combination of two or more of these factors

BLEACHING The sensitivity that occurs with bleaching is a result of a reversible pulpitis that is caused by the flow of dentinal fluid from osmolarity changes in the pulp These changes occur when the bleaching material rapidly penetrates enamel and dentin to the pulp. Hydrogen peroxide and urea penetrate through integral enamel, through the dentin, and into the pulp in 5 to 10 minutes

BLEACHING Most often, the sensitivity is generalized The estimates of tooth hypersensitivity caused by whitening are usually approximately 60% Usually higher concentrations of peroxide results in a greater degree of sensitivity. The addition of low levels of potassium nitrate to tray bleaches has reduced but not eradicated sensitivity.

PERIODONTAL TREATMENT Unfortunately, patient discomfort often occurs while undergoing periodontal treatment. Postoperative pain and dentin hypersensitivity are often occurrences. Some patients find both the nonsurgical and surgical treatment painful. It has been reported that periodontal therapy can be an important source of dentin hypersensitivity.

TREATMENT—SELF-APPLIED AND OFFICE SUPPLIED Self-applied treatments to reduce sensitivity consist of materials that occlude dentinal tubules, coagulate or precipitate tubular fluids, encourage secondary dentin formation, or obstruct pulpal neural response. Desensitizing toothpastes that contain potassium salts, either nitrates or chlorides, are believed to act by depolarizing the nerve surrounding the odontoblastic process, resulting in interference of transmission. Usually

LASER TREATMENT The treatment seems to be only transient, however, and the sensitivity returns in time. In order for a laser to actually alter the dentin surface, it has to melt and resolidify the surface. This effectively closes the dentinal tubules. This does not occur. It is felt that laser treatment reduces sensitivity by coagulation of protein and without altering the surface of the dentin. Dicalcium phosphate-bioglass in combination with Nd:YAG laser treatment has sealed dentin tubules to a depth of 10 mm, and dicalcium phosphate-bioglass plus 30% phosphoric acid occluded exposed tubules up to 60 mm.

FLUORIDE TREATMENT Fluorides reduce the permeability of dentin probably by precipitation of insoluble calcium fluoride inside the dentinal tubules and reduce sensitivity. PRO-ARGIN This material was able to plug and seal exposed dental tubules to decrease sensitivity. OXALATE Pashley and Galloway38 felt that using potassium oxalate resulted in calcium oxalate crystals, occluding the tubules

CASEIN PHOSPHOPEPTIDE–AMORPHOUS CALCIUM PHOSPHATE The peptides present in Recaldent become bound to the dentin surface and this causes a mineral deposit formation in the dentin surface resulting in decreased opening of the dentinal tubules CALCIUM PHOSPHATE PRECIPITATION Chiang and colleagues44 found a mesoporous silica biomaterial containing nanosized calcium oxide particles mixed with 30% phosphoric acid can occlude dentinal tubules and considerably reduce dentin permeability even in the presence of pulpal pressure.

CARBONATE HYDROXYAPATITE NANOCRYSTALS AND SODIUM FLUORIDE/POTASSIUM NITRATE DENTIFRICE Synthetic hydroxyapatite (carbonate hydroxyapatite) biomimetic nanocrystals, introduced recently, have demonstrated the ability to remineralize altered enamel surfaces and close dentinal tubules.There is a progressive closing of the dentinal tubules in several minutes and subsequently a remineralized layer forms in a few hours. GLUTARALDEHYDE based on aqueous glutaraldehyde, which occludes the tubules by cross-linking of dentinal proteins.

SEAL & PROTECT AND ADMIRA PROTECT The material is applied to a slightly moist surface, air dried, and light cured and then a second application is applied and light cured for 10 seconds. PREHYBRIDIZED DENTIN Prehybridized dentin or immediate dentin sealing has been suggested to make the dentin less sensitive while a restoration is fabricated in the laboratory. Because a hybrid layer is created immediately after preparation, teeth treated with the immediate dentin sealing technique were better able to tolerate thermal and functional loads in comparison to teeth that were sealed when the restorations were placed.51 VARNISH