A

In clinical studies the perforator for intra-osseous (Stabident/X-tip) injections in mandibibular molars is routinely placed 2–3 mm apical to the crestal bone on the attached gingiva distal to the tooth to be anesthetized; this avoids root damage and gives direct access to cancellous marrow spaces for rapid solution spread [Gallatin et al., 2003, PMID 14558586; Brown, 1999, PMID 10726552]. Therefore, for a mandibular second molar the optimal site is distal to the molar.