Distal probing depth and attachment level of lower second molars following surgical extraction of lower third molars: a literature review.

A review of the literature is made to evaluate factors that influence probing depth and attachment level on the distal aspect of the lower second molar (L2M) following extraction of a lower third molar (L3M). The PubMed database was searched for studies published between 1997 and March 2009 using the following keywords: mandibular third molar, distal periodontal defect, distal probing depth, distal attachment level, flap design. Randomized prospective studies, with a minimum follow-up of three months for which the full text could be obtained, and that indicated the attachment level and/or probing depth on the distal surface of the L2M in both the preoperative and postoperative periods were included. In the studies obtained, flap design had no influence on distal probing depth or distal attachment level of the L2M following extraction of an L3M. Curettage of the distal radicular surface of the L2M, together with oral hygiene control by the dentist, reduced probing depth values. Various authors recommend bone regeneration techniques in patients with a distal periodontal defect prior to extraction. The placing of membranes (resorbable or nonresorbable) is not justified; however, the use of demineralized bone powder or platelet-rich plasma gel reduces the distal probing depth and attachment level of the L2M.