The therapeutic approach to the periodontal patient tends to follow a sequence of investigations based on the severity of the condition and the degree of patient response to each step. It is always advisable to instruct or strengthen the patient in the correct oral hygiene maneuvers at home. Secondly, the so-called causal therapy, which corresponds to root smoothing (scaling and root planing), is carried out. Finally, depending on the anatomical and pathological substrate found and the degree of compensation already obtained, different types of surgery can be planned. An open flap operation has an important therapeutic potential but, by definition, is also subject to a certain level of investigation. For this reason, it is advisable, when possible, to implement any measure useful to minimize possible discomfort. For example, when the intervention is extended to a wide area of the upper arch, it is possible to avoid subjecting the patient to a series of random infiltrations in the vestibular and palatal areas. This is possible by performing the AMSA injection, a technique first described by Friedman and Hochman in 1997, which allows the anaesthetization, with a single injection, of the pulp of the teeth from the central incisor to the second premolar with the corresponding hard and soft tissues. A further advantage is that it is a circumscribed anesthetic, i.e. it does not extend to the adjacent collateral areas of the lip, nose, and lower eyelid. As Ahad has recently confirmed, the method favors a reduction in the use of the local anesthetic drug and the vasoconstricting agent associated with it (in the cases relating to the study considered later, approximately 1.4 of the 1.8 mL of solution contained in the cartridge are used), while still ensuring a valid haemostatic effect.
The injection point is located at the bisection between the first and second premolars, halfway between the free gingival margin and the medium-palatine suture. This is where the anterior and middle alveolar nerves (hence the acronym AMSA) converge.
The procedure can be carried out using a normal anesthetic syringe, but it is also effective, from the patient’s point of view, to be combined with computer-controlled local anesthetic delivery (CCLAD) systems.
The study by Tandon and colleagues (2019) involved 35 subjects – selected from a pool of 612 periodontal patients – treated after anesthesia with the AMSA technique. Success rates of 94.14% and 87.89% were evaluated for palatal soft and hard tissues, and 49.22% and 43.75% for vestibular counterparts.
In conclusion, the AMSA technique conducted by CCLAD should be considered a first line in the anesthesiologic approach of open-flap periodontal treatment. It is fully effective on the palatal side and less effective on labial/buccal tissues. This possible deficit is perfectly compensated for by the fact that the same CCLAD machine can be used to perform supra-periostial supplemental anesthesia with absolutely less discomfort than the conventional infiltration technique.