Buffered Lidocaine in the Pediatric Dental Patient

Local anesthetic buffered with sodium bicarbonate has been suggested to reduce pain, discomfort and onset time of local anesthesia on injection into tissue, compared to non-buffered solutions. Buffered local anesthesia has been used in medicine, however intraoral injections with buffered solutions are less common in dentistry. Most research has focused on adult perception of pain on administration of buffered local anesthetic. There have been few studies and inconclusive evidence to show that buffered lidocaine reduces the perception of pain on administration in children. The purpose of this interventional study is to assess pain reduction and onset time on injection of buffered 2% lidocaine with 1:100,000 epinephrine in children.

This project's primary aim is to evaluate pain perception in buffered vs non-buffered local anesthesia in children undergoing routine dental treatment. The secondary aim is to evaluate if the buffered solution results in a faster onset of local anesthesia compared to conventional solution. Through a well-designed study, we hope to contribute to the profession's understanding of advanced local anesthesia techniques in children.

This study has been designed as a longitudinal, double blind, crossover study. Specifically, a split mouth design will be implemented to investigate if there is a significant difference in pain perception between administering buffered local anesthesia versus conventional local anesthesia in a pediatric patient. We will also investigate time of onset of local anesthesia and compare buffered to non-buffered solutions. Patients will be treated by a single pediatric dental resident while being overseen by a board-certified attending pediatric dentist at Geisinger Medical Center (GMC). This study will be implemented upon receiving Institutional Review Board (IRB) approval.

The population of interest includes healthy children aged 4-17yo. Children selected for this study will be assessed using the American Society of Anesthesiologists (ASA) physical status classification system. In an effort to control for confounding variables, only healthy children classified as ASA I or ASA II will be included in this study. Children selected for this study will have been determined to require treatment on two occasions on opposite sides of the mouth. Patients will not be excluded if they develop localized infection requiring treatment without systemic antibiotics, however, they will only remain in the study if both sides requiring treatment are either free of infection or if both sides have a localized pain or infection requiring treatment without systemic antibiotics. Patients must have no allergy to lidocaine or history of adverse reactions to epinephrine, no history of hyperthyroidism, and no significant cardiovascular disease per recommendations for administration of local anesthetic according to the American Academy of Pediatric Dentistry (AAPD).12 Buffered lidocaine has been approved for use in patients for medical and dental procedures. There is no additional cost to the patient for receiving buffered versus non-buffered solution.

Prior to initiation of treatment, patients will rate their pain using the Wong-Baker FACES Pain Scale in order to establish a baseline and to help eliminate confounding variables. Also before treatment, a tooth that will be anesthetized will be probed with a periodontal probe to establish a baseline perception of this sensation without local anesthesia. Upon probing without local anesthesia, the patient will ask if they feel a "pinch," in order to establish this baseline. When asked if they feel a pinch, patients will respond with a "yes" or "no" answer, which will be recorded. Patients will be asked to rate their pain related to administration of solution (the second prompt) once the injection is finished. Patients will be observed during injection and assessed by the operator using the Faces, Legs, Arms, Crying Consolability (FLACC) scale. Immediately after local anesthesia, patients will be asked to rate the pain of injection of solution using the Wong-Baker FACES Pain Scale.

After administration of local anesthetic solution, the onset time of soft tissue anesthesia will be measured by using a periodontal probe in the sulcus of the anesthetized tooth or a single tooth in the anesthetized quadrant. This probing will be initiated 15 seconds after initial injection of anesthetic solution and will be repeated at 15 second intervals until local anesthesia is achieved. After each probing attempt, patients will be asked if they felt a "pinch". Once the patient answers "no," the time of onset, in number of seconds to achieve anesthesia from injection to a "no" answer, will be recorded.

Data will be analyzed using t-tests to examine treatment differences. Given patients will be treated with both methods, they will act as their own controls and paired t-tests will be utilized. If covariates are identified (e.g., patients' baseline pain perception), Repeated measure ANOVAs will be utilized with patients as within-subject variable and the patient experience as the outcome.

Eligibility Criteria:
Inclusion Criteria:

1. Patients requiring restorative or surgical dental treatment on two occasions on opposite sides of the mouth; either both maxillary or both mandibular quadrant/sextant involving comparable teeth/areas
2. Patients able to undergo dental treatment in the dental clinic without general anesthesia, sedation, or anxiolysis
3. Patients 4-17 years of age
4. Patients classified as ASA I or ASA II
5. Patients of parents who can read, write and give consent in English

Exclusion Criteria:

1. Patients with allergy to local anesthetic
2. Patients who are pregnant or nursing
3. Patients with cardiac concerns or contraindications to epinephrine
4. Patients unable to undergo dental treatment in the clinic for behavior or medical reasons
5. Patients requiring anxiolysis, sedation, or general anesthesia
6. Patients unable to keep dental appointments or return for dental appointments
7. Patients who do not meet inclusion criteria
8. Patients who experience a missed block (IANB) during injection