Efficiency of a Guiding Device for Inferior Alveolar Nerve Block, EZ-Block®, Compared to a Conventional Freehand Administration.

Efficiency of a Guiding Device for Inferior Alveolar Nerve Block, EZ-Block®, Compared to a Conventional Freehand Administration.

Efficacy of a Guiding Device for Inferior Alveolar Nerve Block, EZ-Block®, Compared With a Conventional "Freehand" Administration, in Providing Anesthesia During Surgical Removal of Impacted Lower Third Molar.

The success rates reported in the literature for the various truncal anesthesia techniques are extremely variable and have shown a lack of reproducibility of the techniques. The use of the EZ-BLOCK® guidance system would increase this success rate in a significant and reproducible way, as it is based on individualized anatomical foundations and therefore adapted to inter-patient variability. In order to determine its effectiveness in clinical situations encountered in current practice, a comparative clinical study of the 2 techniques (freehand reference technique and using the EZ-BLOCK® system) is necessary.

The use of loco-regional anesthesia in the mandibular foramen (Inferior Alveolar Nerve Block - IANB) is part of the therapeutic arsenal for any Dental Surgeon or specialist in Oral Surgery or Endodontics. These local-regional anesthesias are indicated for restorative, endodontic and single and/or multiple surgical treatments of mandibular teeth homolateral to the infiltrated side. The so-called "conventional" freehand reference technique was described by William Steward Halsted and compared in numerous studies to other truncal anesthesia techniques such as Gow Gates or even Akinosi-Vazirani. Certain anatomical landmarks must be accurately identified by the operator to reduce the percentage of failure of this technique. Conventional IANB is associated with a 40% failure rate in surgical removal of the lower third molars included, which is the highest percentage of all clinical failures obtained under local anesthesia. The purpose of this study is to compare the success rate of a IANB guidance device, EZ-Block®, with traditional freehand anatomic administration in the surgical removal of impacted lower third molars. The use of the EZ-BLOCK® guidance system would increase the success rate significantly and reproducibly because it is based on individualized anatomical foundations and is therefore adapted to inter-patient variability.

In each center, a pair of practitioners has been identified: one practitioner, "Anesthesia", will be in charge of the randomization and the realization of the anesthesia by one of the two techniques (EZ-Block or conventional freehand technique). Another practitioner, "Surgery", will be blinded to the anesthesia technique used. It is this practitioner who will perform the surgical procedure described below.

The system consists of a reusable angulator with a tube, a reusable plunger, and a single-use syringe body. These three components are combined with a single-use needle and an anesthetic cartridge to create the ready-to-use EZ-Block® device.

The injection site is located in the middle of the triangle with an upper base formed, during maximum mouth opening, outside by the mandibular ramus, inside by the mesial pterygoid muscle and above by the lateral pterygoid muscle. The needle is inserted up to the bone contact (about 20mm) while the body of the syringe is directed towards the contralateral premolars or molars. Use of a disposable carpule syringe with aspiration. Use of a 35mm long needle with a 0.5mm diameter. Use of an articaine anesthesia carpule with adrenaline 1/200000.

Once the anesthesia is performed by the "Anesthesia" practitioner either with the EZ-Block® device or by the conventional freehand technique, the surgical procedure will be performed in the same way in both arms, and for each tooth, by the "Surgery" practitioner: The "Surgery" practitioner takes charge of the patient after a post-anesthesia time of 10 minutes and performs a new antisepsis then completes the anesthesia by anesthetizing the buccal and lingual nerve with a carpule of 1.8ml of articaine + adrenaline at 1/200000. The "Surgery" practitioner starts the surgical procedure. In the absence of pain, the practitioner "Surgery" carries out the surgical act in its totality (situation of success for the principal criterion of the study) then records the EVA at the end of the intervention.

The success of the truncal infiltration of anesthetic product will be defined as the absence of recourse to additional anesthesia during the procedure

The success of the truncal infiltration of anesthetic product will be defined as the absence of recourse to additional anesthesia during the procedure (binary criterion yes / no).

Inclusion Criteria: Male or female, 18 years of age or older Dental panoramic radiograph or cone beam examination less than 6 months prior to inclusion Clinical criteria and similar radiographs of the 2 mandibular third molars: Stage of root planing Normoposition, horizontal Type of eruption: disincluded, impacted, impacted Anatomical relationship between inferior alveolar nerve and mandibular wisdom tooth apices similar for both sides Affiliation to a social security scheme Informed consent, dated and signed before any study procedure is performed Exclusion Criteria: Pregnant or breastfeeding woman Known allergy to the anesthetic molecule or to a component of the anesthetic carpule Contraindication to the use of vasoconstrictor in dental anesthesia Contraindication to a therapeutic procedure under local anesthesia Patients taking TKA for another medical reason Presence of a cystic pathology related to at least 1 of the 2 mandibular third molars to be extracted Limitation of mouth opening Associated systemic pathology requiring priority management Inability of the patient to comply with study follow-up and scheduled visits (especially for second wisdom tooth avulsion) Patient under legal protection

Odontologie et traitement dentaire Pôle clinique des voies respiratoires Faculté de chirurgie dentaire

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Ravi Kiran BS, Kashyap VM, Uppada UK, Tiwari P, Mishra A, Sachdeva A. Comparison of Efficacy of Halstead, Vazirani Akinosi and Gow Gates Techniques for Mandibular Anesthesia. J Maxillofac Oral Surg. 2018 Dec;17(4):570-575. doi: 10.1007/s12663-018-1092-5. Epub 2018 Feb 26.

Alternative mandibular nerve block techniques: a review of the Gow-Gates and Akinosi-Vazirani closed-mouth mandibular nerve block techniques

Comparison of Efficacy of Halstead, Vazirani Akinosi and Gow Gates Techniques for Mandibular Anesthesia