Table 2.

Periodontitis stage (table based on Tonetti [5]) representation of the categories in italics for case 1, bold for case 2, and bold italics for the same category

Stage		I	II	III	IV
Severity	Interdental CAL	1–2 mm	3–4 mm	≥ 5 mm
	RBL	< 15%	15–33%	> 33%
	Tooth loss due to periodontitis	No tooth loss		≤ 4	≥ 5
Complexity		Max PPD ≤ 4 mm, mostly horizontal	Max PPD $\ge 5$ mm, mostly horizontal	In addition to stage II: PPD ≥ 6 mm, vertical bone loss > 3 mm, FB II–III, moderate ridge defect	In addition to stage III: need for complex rehabilitation due to masticatory dysfunction, tooth mobility degree ≥ 2, bite collapse, drifting, flaring, less than 20 remaining teeth
Extent		Local		Generalized