Advances in the treatment of root dentine sensitivity: mechanisms and treatment principles D.G. GILLAM & R. ORCHARDSON There are limited studies specifically on the prevalence of root dentine hypersensitivity or root sensitivity per se; most of the published information relates to the prevalence of dentine hypersensitivity (DH). Several investigators have suggested that there may be some justification on the basis of differing pathologies of distinguishing between those individuals complaining of DH who have relatively healthy mouths with those who complain of DH as a result of periodontal disease and/or its treatment. It is generally recognized that those individuals diagnosed with periodontal disease and having periodontal therapy including scaling procedures may have a higher prevalence than those who present with healthy mouths and evidence of gingival recession. The availability of a vast array of treatments, however, would indicate either that there is no one effective desensitizing agent for completely resolving the discomfort or that the condition, due to its highly subjective nature, is difficult to treat irrespective of the available treatment options. The importance of implementing preventative strategies in identifying and eliminating predisposing factors in particularly erosive factors (e.g. dietary acids) cannot be ignored if the practitioner is going to treat this troublesome clinical condition successfully. This paper will review the published literature and provide information as to the prevalence of the condition, its etiology and causal factors, as well as recommendations for the clinical management of the problem. Definition According to Addy et al. (1), dentine hypersensitivity (DH) is characterized by ‘pain derived from exposed dentine in response to chemical, thermal, tactile or osmotic stimuli which cannot be explained as arising from any other dental defect or pathology.’ A recent modification to this definition has been made to replace the term ‘pathology’ with the word ‘disease’ (2) presumably with a view to avoid any confusion with other conditions such as atypical odontalgia. Tradi- tionally, the term dentine hypersensitivity was used to describe this distinct clinical condition; however, several authors have also used the terms cervical dentine sensitivity (CDS) or cervical dentine hyper- sensitivity (CDH) or dentine sensitivity (DS), and root dentine sensitivity (RDS)/root dentine hypersensitiv- ity (RDH) (1, 3–8). While accepting there may be justification for some of these terms to describe the condition, Addy (3) advocates the retention of the term dentine hypersensitivity for traditional reasons. Addy (3) also believes that there may be some justification in distinguishing between those indivi- duals complaining of DH who have relatively healthy mouths from those who complain of DH as a result of periodontal disease and/or its treatment. Recently, the term root (dentine) sensitivity (RS/RDS) or root dentine hypersensitivity (RDH) has been used (6–8) to describe sensitivity arising from periodontal disease and its treatment. The rationale is that sensitivity following periodontal therapy may be a distinct condition from that of DH occurring after hydrodynamic stimulation (6–8). However, if the pain from RDS is provoked by hydrodynamic stimuli, then one could argue that DH and RDS are essentially the same condition. Addy (9) also posed a question as to whether DH is a tooth wear phenomenon with toothbrushing and toothwear (dental tribology 1 ) as etiological factors in the localiza- tion and initiation of DH. As a result, he recommended 1 Tribology. The study of wear that investigates the relation- ship between lubrication, friction, and wear. 13 Endodontic Topics 2006, 13, 13–33 All rights reserved Copyright r Blackwell Munksgaard ENDODONTIC TOPICS 2006 1601-1538