Achieving the minimum pain experience by buccal nerve and superficial cervical plexus blocks in radiofrequency treatment

Thermage is a monopolar radiofrequency (RF). It has become an indispensable part of facial and body youthful methods. Although the current device is constantly improving in epidermal cooling techniques and even automatically measures the local impedance value, applying surface anesthesia can take some of the pain away caused by thermage, and the patient's severe pain in the jaw and neck areas is still difficult to resolve.


| INTRODUC TI ON
The monopolar radio frequency system represented by thermage as a noninvasive skin-rebuilding tool has a strong attraction in firming and anti-aging. 1 The device currently included in this research group is the four-generation and fifth-generation systems of thermage (Thermage Inc.). 2 This procedure is commonly used to treat wrinkles, fine lines, and skin flaccidness. 3During the process, a handheld device delivers radiofrequency (RF) energy to the skin, which heats the collagen and causes it to contract, resulting in tighter, and smoother skin. 4During the thermage procedure, A majority of patients may experience minor discomfort or a sensation of heat. 5A total of 5700 patients were investigated in one study for thermage treatments. 6rty-five percent of patients thought the procedure was too painful.Even with the newer techniques, 5% thought the process was too painful.This procedure applies a tip-freezing spray that keeps the epidermis cool, which prevents blistering and crusting and reduces pain during the process.Pain is caused by the RF treatment level delivered to the dermis and deeper tissues being converted into heat, which can be uncomfortable. 6ring facial and neck treatment, the painful areas, most commonly in the upper and lower edge of the lower jaw, the region of parotid-masseteric fascia, and the neck area. 1 It is also the most important area for facial and neck skin firmness improvement.Due to the deeper level of RF energy penetrating the skin, the treatment level range recommended by the device operation guide is combined with the treatment level range.The traditional surface anesthesia method cannot achieve an effective analgesic effect.Factors such as side reactions and limited resources have caused them to be unable to promote.Even though the new generation of RF devices (thermage CPT and FLX) has improved the epidermal cooling technology.
A study from South Korea shows that 25.5% felt that thermage FLX is more painful than its prior version. 2 Therefore, the pain in treating RF tightness still makes many people fear and difficult to tolerate.
As the treatment process is performed, the heat accumulation has increased.The treatment level should be lower and cause a lost to some extent of therapeutic outcome. 7 there any way to improve the comfort of patients treated with thermage treatment? 8Woffles T.L. Wu describes the use of a combination of topical 5% lidocaine cream and mesotherapy to improve the comfort of patients undergoing Thermage treatments.The chances of skin burns or fat necrosis are reduced. 9This study used a buccal nerve block (BNB) and a superficial cervical plexus block (SCPB) technique to achieve better analgesic effects.
The buccal nerve (BN), is one of the branches of the anterior division of the mandibular nerve, supplying sensation to the skin over the anterior part of the buccinator and buccal mucosa.After passing between the superior and inferior heads of the lateral pterygoid muscle, it passes forward and downward at the inferior head of the lateral pterygoid muscle, penetrates the muscle ciliary of the title muscle at the anterior edge of the inferior award branch, and then travels over the surface of the buccal muscle. 10Incidentally a BN block is a technique commonly used by dentists or oral and maxillofacial surgeons that involves the injection of local anesthetic into the buccal mucosa, which is the lining of the cheek. 10This minor intraoral procedure is usually used for numbing the lower teeth and gum tissue during dental procedures such as extractions or fillings.
The combination of inferior alveolar nerve, lingual nerve block, and BNB is a common technique used by dentists and extra-oral surgeons.The BNB serves to avoid the pain of intra-oral mucosal dissection and is safe. 11e superficial cervical plexus originates from the ventral branches of the C2 to C4 nerve roots.These nerve roots provide sensation to the skin and superficial structures of the auricle, acromioclavicular joint, clavicle, and anterolateral cervical area.These branches emanate at the midpoint of the posterior margin of the sternocleidomastoid muscle (SCM) at the same level as the thyroid cartilage notch.These roots combine to form four terminal branches.These are the lesser occipital nerve, the greater auricular nerve, the transverse cervical nerve, and the superior clavicular nerve. 12A cervical plexus (CP) block is a procedure used to relieve pain in the neck and shoulder areas.This is achieved by injecting a local anesthetic into the CP, a network of nerves in the neck. 13But ours is only one of the superficial cervical plexuses.A CP block can treat various conditions, including whiplash injuries, headaches, and neck pain. 14Overall, it is a relatively simple procedure that can be performed outpatient, requiring minimal recovery time. 15e BN block is used to anesthetize the skin sensations in the cheek area. 12Combining the BNB and SCPB effectively provides anesthesia to the lower face and neck region. 16These techniques offer comprehensive anesthesia to the lower face and neck region, allowing for a more comfortable and pain-free procedure.The BN and superficial CP blocks are safe and effective techniques used in various surgical procedures for many years.These two nerve block techniques and their combined application in cosmetic dermatology (or radiofrequency therapy) have not been reported.We aim to explain how we use the combination of BNB and SCPB to improve the comfort of the patient's face and neck monopolar RF treatment of patients.The study was designed as a cross-sectional study.We divided the patients into two groups according to their willingness to test; those who had the wish to use the new nerve block method were set as the experimental group, and the others who used the traditional anesthesia protocol were set as the control group.In this study, patients were asked to rate the level of VAS pain score within 1 h of the procedure, and this was recorded.The Suzhou Industrial Park Huibang Zhimei Medical Beauty Clinic Co., Ltd Unit Ethics Review Committee approved and conducted the study in the unit.Before incorporating research, all patients with skin types III and IV who participated in the study had signed an informed consent.

| The combination of the BNB and SCPB
See Figure 1 for the description of nerve distribution.The following describes the specific steps: 1. Use lidocaine cream (Brand: Beijing Ziguang Compound Lidocaine Cream contains 25 mg of proparacaine and 25 mg of lidocaine per gram of this product.)for 40-50 min.All of them used the traditional table marijuana method to implement the experimental process based on the most common methods currently used and to maintain consistent conditions.
2. Remove the lidocaine cream on the side of the RF skin completely.
3. Rinse before intraoral injection.8.After accomplishing the treatment of unilateral, the other side is operated in the same method and process.9. Onset of action: 5 min after the nerve block, test the cheek, neck, and make sure if there is a noticeable lack of sensation with a light prick on the end of a cotton swab at the blocked area; this is done to determine the good distribution of anesthesia for treatment measurement.

| Statistical analysis
The characteristics of the subject were summarized and described.

| Clinical features and thermage treatment levels
Eight-nine men and women (average age 35.88, range 26-51) were treated with the thermage and were included in the research.This study included 50 treatments and 39 control patients after applying the conditions (Table 1).All control groups are women, and two men were included in the treatment group.In the treatment group treated with thermage, the percentage of patients treated with treatment levels above level 4 in the minimum power in the frontal, mid-facial, mandibular area, and neck were 6%, 26%, 16%, and 0%, respectively.The percentage of patients treated with treatment levels above level 4 in the maximum power was 6%, 58%, 48%, and 0%, respectively, while in the control group, this was 0%, 5.1%, 0%, and 0%, respectively.The difference in treatment energy between the two groups was statistically significant (p < 0.05) except for midfacial treatment energy (the minimum level).There was also a trend to be higher thermage treatment levels in the treatment group.The patients' details are listed in Table 1.

| Detailed method of BN block
Figure 2 describes the precise method of needle insertion.With a slight posterior tilt and wide mouth opening, the mandibular plane is brought as parallel to the floor as possible, with the syringe facing the direction of injection from the contralateral corner of the mouth, 1 cm above, and like the mandibular plane.The entry point is divided at two points, 2-3 mm lateral to the midpoint of the pterygomaxillary ligament or pterygomaxillary crease (red line) (23), and 1-1.5 mL of lidocaine (1.5%) is injected-the method of BNB demonstration reference Video S1.

| Detailed method of SCPB
1-1.5 mL of lidocaine was injected from the midpoint of the outer edge of the SCM to the surrounding area; the injection direction/ dose can be adjusted according to the treatment site, as the superficial CP penetration point may be variable, avoid injecting too shallow and press lightly to make the drug dispersed, the distribution range is slightly larger to block more on the neck, the level is located subcutaneously, avoid injecting blood vessels.See Figure 3 and Video S2 for a detailed scheme.

| Comparison of patient's visual analog scale (VAS) level using the combination of BNB and SCPB protocols with other patients
In Table 2, the pain scores in thermage treatment showed no significant difference in the facial pain sensation of patients in the TA B L E 1 Clinical and baseline characteristics.(Continues) frontal and mid-facial areas.The intraoperative pain level of patients treated in the mandibular region and neck area showed significant differences.The percentage of patients with a level of 5 or more in both groups was 4% and 4% in the treatment group and 48.6% and 92.3% in the control group, respectively, and the pain sensation of patients in the treatment group was significantly higher than that of the control group (p < 0.05).Although there was no difference in pain perception between the treatment group and the control group in patients treated with the frontal and midfacial areas (Figure 4A,B), The distribution in mandibular area and neck VAS scores were found to be concentrated in low level (1-4)   in the treatment group and high scores (>4) in the control group (Figure 4C,D), we can conclude that the treatment group can also provide better anesthesia.

DISCUSS ION
Thermage is a safe and effective treatment for skin tightening and rejuvenation, with results that can last up to 2 years. 1,7,20However, it is important to note that individual results may vary, and multiple treatments may be necessary to achieve optimal results.While thermage is generally a safe and effective treatment, there are some potential side effects to be aware of.These include redness, swelling, and minor discomfort immediately following the procedure.In rare cases, patients may experience blistering, scarring, or changes in skin pigmentation. 9 Patients' feedback on thermal sensation is the effective and preferred method of choosing the best treatment level used in the range. 21Topical anesthetic cream was the most popular mode of anesthesia for thermage, procedural sedation with propofol or nitrous oxide has a disadvantage of not being able to communicate with the patient and it will be increased the possibility of skin burns.Instead of making all feelings disappear in general anesthesia, our experiment focus on significantly alleviating or even resolve pain sensations of the regions that most needed firming and lifting treatment.In contrast, the other regions are still treated with traditional analgesia.The feedback to heat and pain in the midface, which has thicker soft tissues for better tolerance, which can be used as a reference for treatment level selecting to prevent adverse reactions (e.g., burn blisters, crusting, discoloration) occur.In this way, treatment levels of the mandibular regions similar to the midface or even increased by 0.5-1 level to allow for more effective and comfortable treatment.However,  local tissue impedance varies among patients; each patient's pain degree differs. 22itially, the use of thermage was limited due to the perceived pain associated with its use.Still, this limitation has become less concerned with improved anesthesia techniques.Our method is an anesthesia technology that makes the subject more comfortable.
Our study also shows that the mandibular area and neck VAS scores had a higher percentage of low VAS levels in the treatment group.
A study performed in Zelickson's laboratory illustrated the benefit of repeated RF passes at low energies compared to single pass with high energy.However, the subjects for this conclusion did not address the difference in total energy between the two, and the sample was too small with only three cases.Furthermore, the fact that the number of rounds (treatments) for a single treatment tip of the thermage is finite.Therefore, it cannot prove that using the same treatment consumables and applying a lower treatment level will give better results.The authors believe that if used for evaluating monopolar RF thermage, it is a misinterpretation of the conclusions drawn from this experiment. 23This experiment allowed us to communicate with the patient and observe the level of pain response, and quickly find the most suitable energy for the patient, not too low or too high, thus making the treatment more effective.
In our technique, accurate localization is important; the superficial CP must also be blocked during the facial treatment.After a few minutes, the skin of the blocked area uses the sharp tip to test whether the sensation is significantly reduced and compared with the opposite side.It is due to a partial block to the lingual nerve, the patient feels the tongue go numb on occasion.In later practical applications, we stopped using surface anesthetics gradually, and also achieved very good results. 24 the experiment, we found the reasons for the poor analgesic  divide the injection into two or three points nearby.It also helps to add a certain dose of a local anesthetic to the blockade, and the superficial CP block is a subcutaneous injection.The layer of injection is important.By reviewing the literature, (1) the position of the BN is relatively constant, the oral soft tissue mobility is rather large, the PMF may also have variation, and there is some misdirection. 25(2) The superficial CP nerve penetration point also has some anatomical variation.

F I G U R E 4
Comparison between groups of categorical data (histogram).From the picture, you can show the categorical variables by the percentage bar chart.The x parameter will be used as rows of the column linkage table (VAS score).The y parameter will be used as a column in the column linkage table (processing grouping).
-nine patients who underwent thermage in The Suzhou Industrial Park Huibang Zhimei Medical Beauty Clinic Co. in 2022-2023 were included in this study.Patients with allergic reactions to local anesthesia or allergies or participating in other clinical research over the past 30 days have been excluded.All entry objects are healthy people with No history of facial nerve paralysis or palsy.

17
4. BN block: Positioning the inner BN injection point, 2-3 mm at the outer side of the middle end of the PMF pterygomandibular fold, as an injection point, disinfection with povidone-iodine and injection of a 34G 4 mm injection needle at 1.5% Lidocaine 1-1.5 mL to block the BNs. 5.The superficial CPB.The midpoint of the posterior margin of the unilateral SCM, near the point of penetration of the superficial CPB, was disinfected with povidone-iodine.Subsequently, pump back without blood, ensure the needle is not in the blood vessel, and inject 1-1.5 mL of 1.5% lidocaine, which was injected subcutaneously with a 30G 12 mm needle.6. Conventional tattoos are used for the operation area.7. Conduct the face and neck tightening and lifting procedure on the same side.

2. 3 |
The visual analog scale (VAS) pain scoreThe VAS18 pain score is a subjective measure used to assess the intensity of pain experienced by a patient.It is a continuous scale ranging from 0 to 10, where 0 represents no pain and 10 illustrates the worst possible pain.Patients are asked to indicate their pain level by marking a point on a line between these two extremes.The VAS pain score is a simple and quick method of pain assessment and has been widely used in clinical settings.It is a reliable tool for evaluating pain intensity over time and can help healthcare providers to monitor and manage pain effectively.192.4 | Data collection Participants' data is divided into clinical features and thermal treatment levels.The clinical features included age, VAS level of: frontal, midface, mandibular region, neck.Thermage energy indicators included mandibular, jaw area and neck treatment level, and thermage energy.

Frequency
distribution represents categorical variables, whereas continuous variables are reported through the median and interquartile range.Markers explored by Wilcoxon rank-sum test or Kruskal-Wallis's test.F I G U R E 1 The nerve blockade.(A) SCP block area (the nerves marked yellow are blocked), (B) BN block (the nerve marked red is blocked).
a n (%); Mean (SD).b Fisher's exact test; Wilcoxon rank sum test; Pearson's Chi-squared test.TA B L E 1 (Continued) F I G U R E 2 The BN block is before Thermage treatment.The entry point (blue) is 2-3 mm lateral to the midpoint of the PMF pterygomandibular fold (white line).
effect: First, inaccurate positioning, inject at the upper third of the PMF about 2-3 mm next to the area from the point to the midpoint.If you are worried about positioning incorrect of the BN block, F I G U R E 3 SCP block is before Thermage treatment.The red dot is the injection position.White dotted line: Posterior border of the Sternocleidomastoid (SCM) muscle, blue dotted line: External jugular vein.TA B L E 2 Comparison of visual analog scale (VAS) scores.

Variable N Control, N = 39 a Treatment, N = 50 a p-value b
a n (%).b Fisher's exact test.