Recently, Zavattini and Charalambous published a review that considered, at the present state of the art, alternative options in dental anesthesiology compared to the traditional injection technique. Below, some of them are considered.
Computer-controlled anesthesia: CCLAD (computer-controlled local anesthetic delivery) systems are now an acquired and widely documented reality for clinical use, both from the point of view of the variety of applications and as regards feedback from patients. The objective is mainly to reduce the discomfort attributable to the active phase of the injection, which here provides that a constant volume is released at a predetermined and constant pressure. Other advantages are the better tactile feedback and the fact that, although it remains a needle system, the method is less discomforting than the common syringe.
Jet injectors: these systems use mechanical energy, which results in sufficient pressure release to release the anesthetic solution through a very narrow orifice. The patient tends to experience a stimulation that is not painful but pressure; the most interesting aspect, however, is that it is a needleless system. These promising indications, however, require further clinical experimentation: at present, there is not full agreement in the literature also with regard to the success rate.
Iontophoresis: this is another solution of “needleless injection”, tested at a skin level. It is based on the active transport of molecules, ionized or not, through a low voltage direct current – increasing it, there is a certain risk of tissue irritation. In addition, by prolonging the duration, electrochemical polarization is induced across the tissue: this can reduce the amount of molecule transported. Gangarosa documents a triple application in the field of dentistry: in the treatment of dentin hypersensitivity (with fluoride ions), on ulcerative and herpetic lesions and, finally, in topical anesthesia.
Electronic anesthesia: this procedure is based on a methodology already known in the dental field, . This is the transcutaneous electrical nerve stimulation (TENS), whose action to control pain – typically chronic pain – is based on two different concepts. The first is the famous gate theory of Melzack and Wall: by activating the large myelinated Aβ fibers, TENS would exert control over nociceptive transmission by the smaller amyelinated C fibers. In addition to this, the electrostimulation would – the mechanism is not yet completely clear – induce the release of endogenous opioids at the level of the central nervous system.
The TENS system has also been modified for higher frequency intraoral application: electronic dental anesthesia (EDA) has been proposed in the treatment of trigeminal neuralgia and atypical facial pain, as well as in the control of muscle spasms in myofascial syndrome. In the future, it could be used as a real alternative to injective anesthesia in the performance of common dental procedures.