1. INTRODUCTION:

As skin moisture and subcutaneous fat decreases as part of the aging process, wrinkles start to develop. This change, which is also the result of atrophy, degradation, and denaturing of the elastic fivers and collagen fibers in the dermis, first appears as small creases but gradually transforms into larger, deeper wrinkles which cannot be restored spontaneously.¹

Laser therapies, filler, and botulinum toxins have been traditionally employed to improve skin wrinkles; however, they require repeated treatments due to short effects, and they cannot simultaneously improve thick and thin wrinkles.

Lifting techniques have been developed to overcome such limitations. Among the techniques, thread lifting unfolds the wrinkles using threads specifically designed to fix the facial tissues in place. It is particularly effective on wrinkles at the cheek, chin, and neck, and it is also known to stimulate collagen formation, resulting in skin regeneration. It is also simpler in technique and requires shorter recovery period compared to traditional facelift, which has made the more preferred procedure in wrinkle surgery.

This study evaluated the efficacy of cogged polydioxanone (PDO) thread on the improvement of lower face line and jowl

2. PATIENTS AND METHODS:

This study was performed after receiving the approval of Korean Food and Drug Administration and the Institutional Review Board of Wonju Severance Christian Hospital(CR 214001) and Human Resource Training Program for Regional Innovation and Creativity through the Ministry of Education and National Research Foundation of Korea(NRF-2015H1C1A1035925). Prospective subjects who have never undergone procedures on facial wrinkles were recruited, whose wrinkles were then evaluated by Wrinkle Severity Rating Scale (WSRS), and only subjects with grade 3 or 4 wrinkles were enrolled in the study. A total of 55 subjects underwent facial lifting with cogged thread (Secret Cog®, HyundaeMeditech, Korea) from June to September 2014. The cogged thread used in this procedure is a PDO-based absorbable thread with a bi-directional cog around the thread 360 degrees, which results in wrinkle improvement^2-8

The procedure site was locally anesthetized with Emla® cream (Lidocaine2.5%, Prilocaine2.5%)(AstraZeneca) 30 minutes prior to the surgery, and then 2 % lidocaine 1cc was injected in PDO insertion site. A 12cm 19G cogged PDO thread was inserted. A total of 15 to 20 threads were used on both cheeks.(Fig 1) An equal number of threads were used on both cheeks for symmetric wrinkles; however, for asymmetrical wrinkles, the number of required threads differed between the two cheeks. The thread was left in place after withdrawing the needle, and the procedure site was firmly compressed to prevent bruising. The thread insertion site was firmly pressed several times in order to fixate the cog on the skin surface. The end of the thread on the surface of the skin was slightly pulled to lift the facial skin and was then cut with scissors. The threads were then completely inserted into the skin. The time necessary for the complete treatment required was an average of 20 min. Steri-strip was maintained for 3 to 4 days after the procedure, and ice bag was applied to the face for 1 day following the surgery,.

Photographs of the procedure site were taken at post-operative week 1, week 4, and week 12. Two independent plastic surgeons evaluated the post-operative wrinkle status using WSRS, and the patients were asked to express their satisfaction of the procedure using a visual analog scale (10-point scale). Post-operative complications were also recorded.

Figure 1. This drawing shows surgical procedure point and and direction. Point A is shadow line. Point B is insertion site which is 2cm superior from ear upper tip. Dotted line is masseter anterior border and blue arrow is direction of penetrated thread.

3. RESULTS:

Most of the participants were female (52 of 55 participants, 94.5%). The mean age of the subjects were 47.0 ± 9.0 years (31~69 years): there was no young subject in his or her 20s.

On first outpatient visit after the procedure (week 1), the mean satisfaction score of the patients was 7.2 ±1.8, which decreased to 6.9±2.2 on week 4 and 6.6±2.6 on week 12.

The WSRS score after the procedure was compared to that at baseline. On week 1 after surgery, WSRS decreased by greater than 1 point in all subjects except for 1 whose wrinkle score at the right cheek was unchanged. On week 4, wrinkle improvement was observed in every subject, with WSRS score difference greater than 1 on both cheeks. On week 12, 53 (96.4%) maintained WSRS difference greater than 1 on the left cheek, while 54 (98.2%) maintained WSRS difference greater than 1 on the right cheek.

All patients achieved symmetrical facial state at all three post-operative visits.

Immediate post-operative bruises occurred in 5 subjects. Bruises occurred in 47 subjects (85.4%) at any point during the follow-up period, all of which completely cleared (grade V: clear status). Complete resolution of bruises required an average of 13 days.

The patients’ pain was also evaluated on a 10-point scale. The patients expressed the greatest degree of pain immediately after the procedure (3.6±1.8), which steadily decreased to 1.7±1.4 at week 1, 0.6±1.0 at week 4, and 0.04±0.19 at week 12.

Figure 2. Left: Preoperative photographic finding. Right: On week 12 after surgery

Figure 3. Left: Preoperative photographic finding. Right: On week 12 after surgery

Figure 4. Left: Preoperative photographic finding. Right: On week 12 after surgery

Table 1. Improvement of jowl. The alteration of jowl grading score was evaluated at each follow up period.

	Difference compared to baseline	Week 1 N (%)	Week 4 N (%)	Week 12 N (%)
Left	0	-	-	2(3.6%)
	1	20(36.4%)	21(38.2%)	26(47.3%)
	2	33(60%)	33(60%)	25(45.5%)
	3	2(3.6%)	1(1.8%)	2(3.6%)
Total		55(100%)	55(100%)	55(100%)
Right	0	1(1.8%)	-	1(1.8)
	1	20(36.4%)	24(43.6%)	30(54.6%)
	2	32(58.2%)	30(54.6%)	23(41.8%)
	3	2(3.6%)	1(1.8%)	1(1.8%)
Total		55(100%)	55(100%)	55(100%)

Table 2. Patient satisfaction score and pain score on 10-point scale.

Treatment day

Average (±SD)

Week 1

Average (±SD)

Week 4

Average

(±SD)

Week 12

Average (±SD)

Satisfaction Score

7.2(±1.8)

6.9(±2.2)

6.6(±2.6)

Pain Score

3.6(±1.8)

1.7(±1.4)

0.6(±1.0)

0.04(±0.19)

4. DISCUSSION:

Papyrus dating back to 1500 B.C. records ancient Egyptians using sour milk for chemical peels ^2,3: such records show that facial rejuvenation is a historically old aesthetic issue. Furthermore, increased life expectancy has resulted in greater proportion of elderly population, which has alerted the general public to management and treatment of facial wrinkles at earlier phases of life, particularly in 4th to 5th decade of life. Such circumstances have pressed the need for various methods of improving facial wrinkles.

Skin aging and wrinkle formation is not simply a result of dermatologic change- it is a general degenerative change of the skin and the surrounding soft tissue. Since Mitz and Peyronie have made discoveries on superficial musculoaponeurotic system (SMAS), rejuvenation method has progressed from skin-only rhytidectomy to soft tissue repositioning and SMAS lift adaptations, which led to increases in invasive procedures. ^4,5 However, minimally-invasive procedures have begun to gain popularity in recent years for several reasons, including short procedure time, the facility of office-based practice, and less post-operative complications. Thread-lift procedures are generally performed in similar manners despite the variations in minor techniques: the cogged threads are inserted into the subcutaneous layer, which are then pulled to lift the skin to the desired degree. The threads around the insertion site are then cut off.

Cogged threads vary in cog design and material. The thread used in this study is a bidirectional polydioxanone (PDO) thread with cogs designed to wind around the thread 360 degrees. The first kind of bidirectional barbed thread used by Sulamanidze et al was a non-absorbable polymer (polypropylene).⁶ Since then, side effects of non-absorbable thread, including palpation, migration, extrusion, and abnormal facial expression on animation have been reported.⁷ The threads materials have then been replaced by absorbable materials, such as polydioxanone used in this study. Polydioxanone thread is a widely employed suture material and requires 6 to 8 months for complete absorption. It is a monofilament, which minimizes bacterial infection and inflammatory reaction. ⁸ Therefore, PDO is a suitable thread material for enhancing the effect of thread lift while lowering complications

The histological changes that resulted in rat models that underwent procedures with absorbable cogged thread deserve much attention. ⁹ Myofibroblasts appeared around the cog thread 4 weeks after the surgery, and the skin tension and density was maintained due to formation of homogenous fibrous capsule. Thick dermal papillae formation was also noted, which suggests improved collagen synthesis of the basement membrane. These histologic changes imply that improvements in skin wrinkle and texture created by absorbable cogged thread is not only the result of physical tension created by the thread- the thread promotes collagen formation, which leads to skin rejuvenation.

The WSRS score was evaluated for each surgical site after the surgery and was compared to baseline. On week 1 after surgery, WSRS score change greater than 1 was observed in 54 subjects (98.2%), and on week 4, every patient showed significantly improved WSRS score. On week 12, 53 subjects (96.4%) maintained WSRS score difference greater than 1 on the left cheek and 54 subjects (98.2%) for the right cheek. Overall, the skin wrinkles improved, although 1 to 2 patients showed poorer improvements at certain time point.

The satisfaction score of the subjects tended to decrease after the first visit. The tension created by PDO threads reaches the peak immediately after the procedure and then decreases over time as the absorbable thread starts to degrade, which weakens the pull on the skin. However, collagen begins to form around the thread, which makes the wrinkle improvement more permanent. Taken together, the wrinkle improvement appears to have been dramatically improved at week 1 after the procedures, which is actually an overcorrection of the wrinkle due to edema. However, as facial edema disappears, the overcorrected wrinkles start to settle in the skin, which, especially compared to the dramatic change shown immediately after the surgery, may be understood by the subjects as inferior result. This may explain the lower satisfaction score reported at week 12 after surgery.

All patients reported post-procedural symmetry at all follow-up visits. In 9 cases (16.4%), WSRS score differed between the two surgical sites, which suggest that thread lift is also effective in achieving symmetrical wrinkles.

The mean immediate post-operative pain score was 3.6±1.8, which was relatively low. This may have been due to the use of EMLA cream. Pain score then steadily decreased over time, and most subjects expressed little to no pain after the procedure.

47 subjects (85.4%) reported bruises after surgery. For 5

patients who developed bruises immediately after the procedure, it took a mean of 13 days for complete resolution (grade V: clear status). While a significant number of subjects also reported bruises at some point after the procedure, the complication was expected, and the bruises completely disappeared at the termination of the study.

5. CONCLUSION:

In conclusion, this study found the use of cogged polydioxanone (PDO) thread on intermediate wrinkles to clearly improve aging lower face. It also improved asymmetrical facial wrinkles. Thread lift is a safe and effective procedure with the advantages of simple technique, short procedure time, and quick postsurgical recovery time, in addition to lack of pain and complications. Although it cannot substitute the face lift surgery, however, in mild to moderate lower face wrinkle, it can improve the lower face contour with simple procedure.

This technique is appropriate and effective for patients with mild to moderate degree of facial wrinkles.

6. ACKNOWLEDGEMENT:

This work was supported by the Human Resource Training Program for Regional Innovation and Creativity through the Ministry of Education and National Research Foundation of Korea(NRF-2015H1C1A1035925) and approval of Korean Food and Drug Administration and the Institutional Review Board of Wonju Severance Christian Hospital(CR 214001).

7. REFERENCE:

1. Friedman O. Changes associated with the aging face. Facial Plast Surg Clin North Am 2005;13:371–80.

2. Guerrero-Snatos J. Surgical correction of the fatty fallen neck. Ann Plast Surg 1979;2:389.

3. Lemmon ML, Hamra ST. Skoog rhytidectomy: a fiveyear experience with 577 patients. Plast Reconstr Surg 1980;65: 28397.

4. Kaye BL. The extended neck lift: the “bottom line”. Plast Reconstr Surg 1980;65:42935.

5. Kaye BL. The extended facelift with ancillary procedures. Ann Plast Surg 1981;6:33546.

6. Mendelson BC. Correction of the nasolabial fold: extended SMAS dissection with periosteal fixation. Plast Reconstr Surg 1992;89:82233. \

7. Hamra ST. The deepplane rhytidectomy. Plast Reconstr Surg 1990;86:5361.

8. Stuzin JM, Baker TJ, Gordon HL, et al. Extended SMAS dissection as an approach to midface rejuvenation. Clin Plast Surg 1995;22:295311.

9. Mendelson BC. Extended subSMAS dissection and cheek elevation. Clin Plast Surg 1995;22:32539.

10. Hunt H. Plastic Surgery of the Head, Face and Neck. Philadelphia, PA: Lea & Febiger; 1926.

11. Bames HO. Frown disfigurement and ptosis of eyebrows. Plast Reconstr Surg. 1927;19:337-340.

12. Mitz V, PeyronieM. The superficial musculo-apomeurotic system (SMAS) in the parotid and cheek area. Plast Reconstr Surg. 1976;58(1):80-88.

13. Paul MD, Calvert JW, Evans GR. The evolution of the midface lift in aesthetic plastic surgery. Plast Reconstr Surg. 2006;117(6):1809-1827.

14. Sulamanidze M, Sulamanidze G. APTOS suture lifting methods: 10 years of experience. Clinics in Plastic Surgery 2009;36:281–306.

15. Paul MD. Barbed sutures in aesthetic plastic surgery: evolution of thought and process. Aesthet Surg J 2013;33:17S–31S.

16. Tajirian AL, Goldberg DJ. A review of sutures and other skin closure materials. J Cosmet Laser Ther 2010;12:296–302.

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Received on 20.04.2018 Modified on 11.05.2018

Research J. Pharm. and Tech 2018; 11(11): 4846-4849.

DOI: 10.5958/0974-360X.2018.00881.8

Effectiveness of Cogged Polydioxanone Thread for Aging Lower Face Improvement

2. PATIENTS AND METHODS:

Figure 1. This drawing shows surgical procedure point and and direction. Point A is shadow line. Point B is insertion site which is 2cm superior from ear upper tip. Dotted line is masseter anterior border and blue arrow is direction of penetrated thread.

3. RESULTS:

Figure 3. Left: Preoperative photographic finding. Right: On week 12 after surgery

Figure 4. Left: Preoperative photographic finding. Right: On week 12 after surgery

Table 1. Improvement of jowl. The alteration of jowl grading score was evaluated at each follow up period.

Table 2. Patient satisfaction score and pain score on 10-point scale.