Study of OraVerse® for Safety and Efficacy in Pediatric Dental Patients

Inclusion Criteria: * Male or female, 2 to 5 years of age * Sufficiently healthy as determined by the Investigator to receive routine dental care * Requires a restorative procedure (restoration/filling) in a single quadrant of the mouth * Requires local anesthesia with lidocaine 2% with 1:100,000 epinephrine administered by submucosal injection * For subjects undergoing mandibular procedures, require an inferior alveolar nerve block for the restorative procedure * Dental procedure(s) completed within 60 minutes of injection of local anesthetic * For subjects 4 and 5 years of age, can be trained in standardized lip/tongue palpation procedure and pFAB * Subjects who are trainable in pFAB and standardized lip/tongue palpation procedure have either: * normal pFAB at baseline prior to administration of local anesthetic and * at least one abnormal function (smiling, speaking, drinking or drooling) at the completion of the dental procedure OR * normal lip sensation at baseline prior to administration of local anesthetic and * numbness of the relevant lip quadrant at completion of the dental procedure * Subjects give written or verbal assent, as capable and appropriate, and parent(s) or legal guardian(s) give written informed consent Exclusion Criteria: * Weight less than 10 kg * Weight less than 15 kg if 4 or 5 years of age * History or presence of any condition that contraindicates routine dental care or use of local anesthetic * Requires more than ¼ cartridge of local anesthetic if weight is ≥ 10 kg and \< 15 kg, more than ½ cartridge of local anesthetic if weight is ≥ 15 kg and \< 30 kg, and more than 1 cartridge of local anesthetic if weight is ≥ 30 kg, excluding supplemental injections * Allergy or intolerance to lidocaine, epinephrine, sulfites, phentolamine, nitrous oxide or topical benzocaine * Has used any investigational drug and/or participated in any clinical study within 30 days of study drug administration * Has participated in this study or any previous study of phentolamine mesylate for reversal of local soft tissue anesthesia (STA) * Any use of commercial OraVerse™ within 30 days of study drug administration * Use of opioid or opioid-like analgesics within 24 hours prior to administration of local anesthetic * Requires the use of local anesthetic other than lidocaine 2% with 1:100,000 epinephrine to perform the scheduled dental procedure * Requires the use of general anesthesia or sedatives except for nitrous oxide to perform the scheduled dental procedure * Any condition which in the opinion of the Investigator increases the risk to the subject of participating in this study or decreases the likelihood of compliance with the protocol