Postanesthetic Cold Sensibility Test as an Indicator for the Efficacy of Inferior Alveolar Nerve Block in Patients with Symptomatic Irreversible Pulpitis of Mandibular Molars

Aim of the Work. The goal of the current study was to investigate the capability of the cold test to predict the profound pulpal anesthesia before starting the endodontic treatment of mandibular first molars with symptomatic irreversible pulpitis (SIP). Materials and Methods. This study was conducted on the mandibular first molars of 54 patients (35 males and 19 females) with signs and symptoms of SIP. To anesthetize the affected molars, all patients received a single carpule of 2% lidocaine with 1 : 100000 epinephrine using a standardized inferior alveolar nerve block (IANB) technique. The cold test was conducted before beginning the endodontic procedures and after gaining lip numbness, and the results were reported as either positive or negative response. The root canal preparation (RCP) was then initiated and the patients’ responses were documented (Gold standard test). True pulpal anesthetic failure was described as a pain perception during the access cavity and pulp tissue removal. True pulpal anesthesia was defined as no pain or discomfort during the access cavity and pulp extirpation. The qualitative variables frequencies and percentages of patients with true/false positive and negative responses were determined and then compared using the Chi-square test. The pain perception of male and female patients during the cold test and gold standard was compared using the Fisher exact test. The following diagnostic parameters were calculated using an online statistical calculator: sensitivity, specificity, predictive values, accuracy, and Youden index. In addition, a receiver operating characteristic curve (ROC) was constructed and the area under the curve (AUC) was calculated. Results. The overall percentage of actual failure of pupal anesthesia was 57%. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and Youden index for the cold test were 0.87, 0.91, 0.93, 0.84, 0.89, and 0.78, respectively. There was no statistically significant difference between male and female patients regarding their responses to cold testing and the gold standard test ( P > 0.05 ). Besides, the patients’ reactions to the cold test were significantly matched with their reactions to the gold standard test ( P < 0.05 ). The area under the ROC was mostly 0.9. Conclusion. The cold test could be a valuable and accurate method for predicting the potential pupal anesthesia before beginning the endodontic treatment of mandibular molars with symptomatic irreversible pulpitis, particularly after obtaining postanesthetic soft tissue numbness.

Nitrous Oxide/Oxygen Effect on IANB Injection Pain and Mandibular Pulpal Anesthesia in Asymptomatic Subjects

The inferior alveolar nerve block (IANB) does not always result in successful pulpal anesthesia. Nitrous oxide may increase the success of the IANB. The purpose of this investigation was to study the effect of nitrous oxide/oxygen (N2O/O2) on IANB injection pain and mandibular pulpal anesthesia in asymptomatic subjects. One hundred five asymptomatic subjects received an IANB after the administration of N2O/O2 or room air/oxygen (air/O2) at 2 separate appointments. After the IANB, subjects rated their level of pain for each phase of the injection (needle insertion, needle placement, and solution deposition) using a Heft Parker visual analog scale. Pulpal anesthesia was evaluated with an electric pulp tester for 60 minutes. The mean pain rating for all 3 injection phases showed a statistically significant reduction in pain when N2O/O2 was used compared with Air/O2 (P &lt; .05). Odds ratios demonstrated a statistically significant increase in IANB success for the N2O/O2 group compared with the air/O2 group. N2O/O2 administration statistically decreased pain for all 3 injection phases of the IANB. In addition, nitrous oxide statistically increased the likelihood of pulpal anesthesia for posterior mandibular teeth. However, the incidence of pulpal anesthesia was not 100%.

Efficacy of Pulpal Anesthesia Using a Needle-less Syringe

The purpose of this study was to investigate the manufacturer's claims regarding a novel needleless intraligamentary local anesthesia injection device (Numbee, BioDent) to provide effective single tooth anesthesia. Investigators compared the Numbee with a traditional inferior alveolar nerve block (IANB) during a restorative procedure on mandibular teeth. A randomized, split-mouth design was conducted with 15 adult subjects receiving an IANB on one side and a Numbee injection on the same tooth type on the contralateral side. Subjects recorded injection pain using the Visual Analog Scale (VAS) and their preferred injection technique. Anesthesia was considered profound with 2 consecutive electric pulp tester readings of 80. If subjects became symptomatic during the restorative procedure, rescue anesthesia was administered. The difference in VAS scores for injection pain between the Numbee and the IANB was not significant (p = .078). For the IANB, the incidence of profound anesthesia was 46%, and required rescue anesthesia was 20%. For the Numbee, the incidence of profound anesthesia was 0%, and required rescue anesthesia was 60%. Subject preference was evenly split (50/50%) between the 2 techniques. The IANB outperformed the Numbee device for achieving profound anesthesia and requiring less rescue anesthesia.