“…It is extremely important to make the right choice between an endodontically or periodontally compromised treated tooth and implant. Therefore, in order to decide whether the tooth is safe or not, data that have to be collected are probing depth, attachment level, mobility, inflammatory and hygiene indices, root anatomy, furcation involvement, and crown-to-root ratio [13, 14], but not enough. Avila et al [15] consider six levels of evaluation to decide whether a tooth can be saved or not; for each level a number of variables are assigned with the green, yellow, and red colours to indicate long-term maintenance favorable, caution recommended, and long-term survival unfavorable, respectively; among these variables as well as parameters related to the specific site, variables relating to systemic condition, compliance, and expectations of the patient together with clinician's skill can be noted.…”