OR48 - Buffered vs. Unbuffered Local Anesthesia in Mandibular Molars Diagnosed with Symptomatic Irreversible Pulpitis

Profound pulpal anesthesia is difficult to achieve in teeth diagnosed with irreversible pulpitis (IRP). Failure to achieve adequate anesthesia has been seen in 30–80% of patients with IRP. Onpharma^TM uses sodium bicarbonate to buffer a standard local anesthetic (LA) solution and make LA pH closer to its pKa. This increases the amount of un-ionized LA that can better cross the nerve membrane and anesthetize the nerve. Studies on the anesthetic efficacy of Onpharma^TM were inconclusive and that may have been because different LA protocols were used. This study aimed to determine if a profound and faster pulpal anesthesia could be achieved in mandibular molars diagnosed with symptomatic irreversible pulpitis using Onpharma^TM buffered LA delivered in a combination of LA methods. Materials and

Methods: 40 subjects with symptomatic irreversible pulpitis in mandibular molar were divided into two groups. The Ctrl. group received an inferior alveolar nerve block (IANB) followed by supplemental buccal and lingual infiltrations using standard LA. The Exper. group received the same protocol but with Onpharma^TM buffered LA. Onset of pulpal anesthesia was defined by consecutive electronic pulp tester (EPT)=80 readings. Profound pulpal anesthesia was determined if a comfortable pulpotomy was reported using Wong-Baker FACES-Visual-Analog Scale (VAS).

Results: A profound anesthesia(p=0.019) was seen in the unbuffered group. The onset time of pulpal anesthesia was similar in both groups: using buffered and unbuffered LA.

Conclusion: Profound pulpal anesthesia was not better achieved using Onpharma^TM buffered LA.