Comparison of Anesthetic Efficacy and Safety Between Inferior Alveolar Nerve Block and the Infiltrative Technique for the Treatment of Peri-implant Diseases in Posterior Mandibular Implants

This study is a triple-blind randomized clinical trial designed to compare the anesthetic efficacy and safety of two local anesthesia techniques used for the surgical treatment of peri-implantitis in posterior mandibular implants: the inferior alveolar nerve block (IANB) and the infiltrative technique (TINF), both performed with 4% articaine and epinephrine 1:100,000.

Background and rationale Peri-implantitis is an inflammatory disease affecting the tissues surrounding osseointegrated dental implants. It is characterized by progressive peri-implant bone loss together with clinical signs of inflammation. It represents one of the most relevant biological complications in implant dentistry.

Initial management of peri-implant diseases usually involves non-surgical therapy, including mechanical debridement of the implant surface, antiseptic irrigation, and, in selected cases, local or systemic antimicrobial therapy. However, when peri-implantitis progresses or does not respond adequately to non-surgical treatment, surgical intervention is often required. Surgical treatment may include flap elevation, removal of granulation tissue, implant surface decontamination, bone recontouring, regenerative procedures, soft tissue surgery, or combined approaches, depending on the morphology and severity of the defect.

Adequate local anesthesia is essential to perform these procedures safely and predictably. This is particularly relevant in the posterior mandible, where dense cortical bone may limit the diffusion of local anesthetic solutions. Traditionally, the inferior alveolar nerve block has been the standard technique for achieving profound anesthesia in mandibular posterior procedures. Although generally effective, its success may be affected by anatomical variation, accessory innervation, technical difficulty, or incomplete nerve blockade. In addition, although uncommon, transient neurosensory complications have been described.

The infiltrative technique has gained interest as a possible alternative, especially when using articaine, which has high tissue diffusion capacity due to its chemical structure. Articaine contains a thiophene ring, which increases lipid solubility and may facilitate penetration through dense tissues. It also has a rapid onset of action and favorable pharmacological characteristics for oral surgery. Despite this, the available evidence suggests that IANB may still provide greater anesthetic predictability in complex surgical procedures. There is a lack of well-designed randomized clinical trials directly comparing IANB and infiltrative anesthesia specifically in the surgical treatment of peri-implantitis in posterior mandibular implants.

For this reason, the study aims to provide controlled clinical data that may help guide evidence-based anesthetic decision-making in this specific surgical context.

Main objective The primary objective is to compare the anesthetic efficacy of the inferior alveolar nerve block and the infiltrative technique during the surgical treatment of peri-implantitis in posterior mandibular implants.

Anesthetic efficacy will be assessed through the need for re-anesthesia during the surgical procedure. The absence of re-anesthesia will be considered evidence of successful anesthesia.

Secondary objectives

The secondary objectives are to compare both anesthetic techniques in terms of:

Safety and incidence of adverse events.

Intraoperative discomfort.

Pain during anesthetic injection.

Postoperative pain intensity.

Duration of anesthesia.

Patient satisfaction with the anesthetic technique and surgical experience.

Need for rescue analgesic medication.

Postoperative complications.

Feasibility of the protocol for a future confirmatory clinical trial.

Hypotheses The main null hypothesis is that the anesthetic efficacy of IANB, measured by the number or frequency of re-anesthesia events during surgery, is not superior to that of infiltrative anesthesia in the surgical treatment of peri-implantitis in posterior mandibular implants.

The alternative hypothesis is that IANB provides superior anesthetic efficacy compared with infiltrative anesthesia in this clinical setting.

Secondary hypotheses include the possibility that IANB may be associated with a different safety profile, lower intraoperative discomfort, reduced postoperative pain, and higher patient satisfaction compared with the infiltrative technique.

Study design The study is designed as a randomized, triple-blind clinical trial. It is also described as a pilot and exploratory study because there is limited previous evidence in this exact clinical context, making it difficult to establish robust assumptions for a definitive sample size calculation.

The trial will be conducted at the Dental Hospital of the University of Barcelona, specifically within the Master's program in Oral Surgery and Bucofacial Implantology.

Study population The study will include consecutive adult patients attending the Implant Maintenance Unit or the Oral Surgery and Implantology service who require surgical treatment of peri-implantitis in posterior mandibular implants.

Patients will be assigned either to the experimental group, receiving IANB, or to the control group, receiving infiltrative anesthesia.

Inclusion criteria

Participants must meet the following criteria:

Age 18 years or older.

Need for surgical treatment of peri-implantitis in the posterior mandibular region.

Absence of relevant uncontrolled systemic disease, corresponding to ASA I or ASA II.

Sufficient intellectual capacity to understand the study, provide informed consent, and complete the questionnaires and pain records.

Exclusion criteria

Patients will be excluded if they meet any of the following conditions:

Pregnancy.

Allergy or hypersensitivity to articaine or epinephrine.

Uncontrolled systemic disease.

Coagulation disorders or medication affecting coagulation.

Ability to recognize the anesthetic technique used, for example dental professionals.

ASA III or higher systemic status.

• To evaluate the adverse effects of the anesthetic techniques (IANB versus infiltrative technique) used in the surgical treatment of peri-implantitis in posterior mandibular implants. [Срок оценки: 7 days]
• To analyze postoperative pain associated with the surgical treatment of peri-implantitis in posterior mandibular implants in patients anesthetized with IANB compared with those anesthetized with infiltrative techniques. [Срок оценки: 7 days]