The Effect of Sonophoresis on Topical Anesthesia: A Pilot Study
Condition: Topical Anesthetic Applied With Sonophoresis
Study type: Interventional
Phase: Phase 1

Summary: 
      The Dental Anesthesia Sonophoresis Device (DASD) is a novel device that is intended to reduce
      the discomfort associated with puncturing the oral mucosa. DASD is a portable,
      battery-powered device that simultaneously generates ultrasonic energy and sonic vibration in
      a small applicator head that can easily reach and adapt to injection sites in the oral
      cavity. The ultrasonic energy provides a sonophoretic effect on the oral mucosa, generating
      micro channels through the lipids between the keratinized cells that make up the stratum
      corneum. Once the benzocaine has permeated the stratum corneum, it is quickly absorbed into
      the soft tissue desensitizing the area and reducing the perception of pain caused by the
      trauma of puncturing soft tissue. Methods: A split-mouth model using 50 healthy subjects from
      the ages of 18 to 50 will undergo needle puncture of the maxillary mucobuccal fold at the
      canine eminence. Prior to the injection there will be randomized application of 20%
      Benzocaine with a device which is a modified battery operated tooth brush that in appearance
      and sound is similar to the DASD which only produces sonic vibration which will be known as
      (SV) or 20% benzocaine with application of the DASD device, that produces ultrasonic as well
      as sonic vibration. Subjects will rate their pain according to the Visual Analog Scale
      (VAS).The purpose of this study is to evaluate whether sonophoresis applied using the DASD
      will eliminate the pain associated with intraoral injections within one minute of
      application.

      Null Hypothesis (Ho): There is no difference in the perception of pain when the DASD is used
      compared to topical anesthetic applied with sonic vibration.

      The Alternative Hypothesis (Ha): There is a difference in pain perception when the DASD is
      used for application of topical anesthetic compared to topical anesthetic applied with sonic
      vibration.
    

Detailed description: 
      Fifty healthy patients between the ages of 18 and 50 will be used for this clinical trial.
      The anatomical site used for this clinical trial is the maxillary mucobuccal fold above the
      canine eminence. This site has been selected because it is an anatomical structure that is
      easily found for all subjects and is reproducible from one side of the patient to the other.
      One side of the patient's maxillary mucobuccal canine area will be dried with dental 2x2
      sponge gauze, then 20% Benzocaine will be applied with an SV for one minute. The site will
      then be punctured using a short 27-gauge needle inserted to the depth of 3mm.

      Immediately after the removal of the needle, the patients will be asked to rate their pain
      according to the Visual Analogue Scale (VAS) model. The VAS is a measurement instrument 100mm
      in length anchored by word descriptors at each end. The subject marks on the line the point
      that they feel represents their perception of their current state.

      On the contralateral side, a 2x2 will be used to dry the mucus, and then 20% benzocaine will
      be applied using the DASD for one minute, followed by a puncture of the oral mucosa with a
      27-gauge needle to the depth of 3mm. Immediately after the removal of the needle, the subject
      will rate their pain according to the same method described above. The application of the
      topical anesthetic by the DASD and SV will be administered by a single investigator for all
      subjects. After administration of topical anesthetic the subjects will be divided randomly
      among six separate investigators who will insert the needle into the mucosa. Neither the
      investigator giving the injection nor the subjects will be told whether the DASD or SV was
      used to administer the topical anesthesia. This will insure a double blind trial. A new
      27-gauge needle will be used for each injection site to standardize each injection.

      Statistical Analysis

      Each patient will be treated prior to injection with a topical anesthetic applied either
      using the SV device or the DASD device. A paired t-test will be used to determine if a
      statistically significant difference exists between pain scores recorded for each of the
      injection sites. For the VAS model, the patient's vertical mark is measured from the left
      hand side in millimeters. The paired t-test will test if the mean difference between SV
      treated sites and DASD, treated sites to determine which of the two hypotheses are true. The
      Null Hypothesis (Ho) is that the mean of the differences in pain scores is zero. The
      Alternative Hypothesis (Ha) is that the mean of the differences in pain scores is not equal
      to zero . A probability value of 0.05 will be used to determine if the difference is
      significant.
    

Intervention name(s): DASD Group; Sonic Vibration (SV)
Intervention type(s): Device; Device
Intervention description(s): Single application of 20% Benzocaine applied for one minute with the DASD ultrasonic and sonic vibration prior to needle puncture.; Single application of 20% benzocaine applied with SV for one minute prior to needle puncture.
Allocation: Randomized
Intervention model: Factorial Assignment
Masking: Double (Participant, Care Provider)
Primary purpose: Basic Science
Keywords: topical anesthetic, sonophoresis