Many of us have sensitive tooth, which shows as twingling sensation when drinking or eating cold food or hot foods, eating sweets, touching tooth with tongue, there are two types of senstivity- dentinal senstivity and pulpal senstivity, which happens when the enamel overlying the tooth is lost or the cemuntum of root is lost which can happen when gum inflamation resulting in root exposure or by flap surgery procedure the root get exposed due to shrinkage of gums, dentinal senstivity can happen due to enamel or cemumtum loss due to brushing too hard, poor oral hygiene long term tooth wear, untreated cavites,an old filling with crack or leak, receeding gums that expose tooth roots, which can be caused by periodontal disease or vigrous brushing, pupal senstivity is caused by decay or infection, a recent filing, a cracked or broken tooth.

Abfraction causing fracture at cervical area.
Treatment of Dentine sensitivity Noninvasive Treatment Dentinal sensitivity can be reduced by brushing twice a day and regular flossing, using fluoride tooth paste and mouth rinse, using tooth paste which reduces sensitivity, by occluding dentinal tubules, but such treatment are reversible. Semi Invasive Treatment Procedure Treatment of such tooth with composite(tooth coloured filling material) or even glass ionomer filling materials will be helpful

Filling with tooth coloured material.
Invasive Treatment Procedures The treatment plan includes crown(ceramic or metal) on tooth, periodontal surgery, root canal treatment or even extraction where the exposure of roots due to gum problems has compromised the tooth to such an extend that it cannot be saved.