Table 3 Definitions of oral mucosal lesions used in studies in Scandinavia

Definition of Axéll 1976 [15]

Snuff dipper's lesion is a lesion of the oral mucosa at the exact site of the regular placing of snuff. The clinical appearance is graded as follows:

Degree 1. A superficial lesion with a colour similar to the surrounding mucosa, and with slight wrinkling. No obvious mucosal thickening.

Degree 2. A superficial, whitish or yellowish lesion with wrinkling. No obvious thickening.

Degree 3. A whitish-yellowish to brown, wrinkled lesion with intervening furrows of normal mucosal colour. Obvious thickening.

Degree 4. A marked, white-yellowish to brown and heavily wrinkled lesion with intervening, deep and reddened furrows and/or a heavy thickening.

Studies using the Axéll 1976 definition

Larsson 1991 [1], Andersson 1995 [2], Andersson 2003 [3], Roosaar 2006 [4], Rosenquist 2005 [5], Axéll 1976 [15], Hirsch 1982 [16], Salonen 1990 [8]^a, Andersson 1989 [18], Andersson 1994 [19] and Rolandsson 2005 [20]

Studies using other definitions

Jungell 1985 [7] – "snuff-induced lesion", not further defined

Pindborg 1963 [13] – "snuff-induced leukoplakia", characterised by a mucous membrane with "a slightly whitish, sometimes yellowish-brown dry appearance with a very delicately folded or finely grooved appearance"

Roed-Peterson 1973 [14] – "oral leukoplakia", defined as "a white patch not less than 5 mm in diameter which cannot be removed by rubbing, and which cannot be ascribed to any other diagnosable disease"

Frithiof 1983 [17] – "snuff-induced lesion", with "a characteristic whitish appearance frequently with a brown discolouration which clearly contrasted with the neighbouring mucosa"