Post-extraction alveolar management
Apical infection (Fig 2) is the most common indication for cheek teeth exodontia, being the reason for 62% of 428 extractions in a recent study (Kennedy et al. 2020). Exodontia of apically infected teeth causes a bacteraemia with potential pathogens, including anaerobes (Kern et al. 2017). Many clinicians administer pre-operative antibiotics (e.g., penicillin and an aminoglycoside) including to help prevent the rare spread of bacteria from infected teeth to distant sites, that can cause infections such as meningitis (Bach et al . 2014; Arndt et al. 2021). When infection of the supporting bones is present, longer-term post-extraction antibiotic therapy is justified. There is less consensus on the routine use of post-extraction antibiotic therapy in other exodontia cases.
Following exodontia, the alveolus should be digitally and visually (using a dental mirror or oral endoscope) examined, as should the apical aspect of the extracted tooth to ensure that no dental fragments remain in the alveolus. If any doubt remains, and always following repulsion techniques or where the apex of the tooth is not intact, post extraction radiography should be performed to ensure that no intra-alveolar dental (or alveolar bone fragments) remain. Any such identified fragments should be immediately removed digitally or using long, right-angled equine dental picks with adjustable heads under visual guidance, and with use of suction of intra-alveolar blood to allow visualisation of mandibular alveoli. If suitable picks are unavailable, high pressure lavage of the alveolus using an equine dental syringe may remove unattached bone or dental fragments. Formation of a new blood clot should now be encouraged, if necessary, by alveolar curettage.
Optimal post-extraction healing will occur in an alveolus that did not have significant pre-existing alveolar bone infection, which has not sustained excessive exodontia-related alveolar bone damage, does not contain dental or bone fragments and which contains a large post-extraction blood clot. The alveolar blood clot should be protected from masticatory forces and food impaction by placing packing material (e.g., polysiloxane, acrylic or surgical swabs [gauze] impregnated with antibiotics, honey or dilute antiseptics) in the more occlusal (e.g., one third) aspect of the alveolus. Excessively deep alveolar packing will mechanically reduce or even prevent alveolar healing. Some clinicians have used antibiotic-impregnated surgical swabs in the more occlusal half of the alveolus to help treat existing and help control post-operative alveolar bone infection (Kennedy et al. 2020). The risk of bacterial antibiotic resistance development must be considered with such local antibiotic therapy. The use of surgical swabs soaked in concentrated antiseptic solutions such as Povidine iodine may risk causing chemical irritation and delayed alveolar healing.
No large objective studies have determined which post-extraction alveolar management is optimal. However, anecdotal evidence indicates that just placing packing material in the alveolus following exodontia and allowing this material to spontaneously dislodge later, is unsatisfactory. This is especially true following exodontia of apically infected Triadan 06-08 mandibular cheek teeth in younger horses (Kennedyet al. 2020; Giegert and Bienert 2021). Instead, the post-extraction alveolus should be actively managed until healing is complete or near complete. The alveolar packing inserted immediately post extraction should be removed about 7-10 days later, and the alveolus digitally examined to assess if it is lined by smooth (developing granulation) tissue over all its surfaces. Rough areas of exposed bone such as caused by alveolar sequestration or dry socket are readily palpated and if these bony areas are loose (i.e. are sequestrae rather than dry socket), they should be removed digitally or using picks.
If the alveolus appears to be healing normally at this first re-examination, it should be gently lavaged, without dislodging the blood clot. The occlusal aspect of the alveolus should be repacked (using less packing material on this occasion) and the alveolus re-examined 1- 2 weeks later to further assess alveolar healing and in particular, for evidence of delayed sequestration. As noted, the most rigorous management is needed following extraction of younger mandibular teeth with apical infection and such cases should have repeated alveolar examinations until healing is very advanced.