Class III malocclusion affects negatively on health, quality of life and psychology. Orthodontic and orthognathic surgery is necessary for adult patients with skeletal class III malocclusion to achieve good function and aesthetic. The subjects were 35 patients at Hanoi National Hospital of Odontostomatology, Viet Duc University Hospital, and Hong Ngoc Hospital from April 2017 to September 2018.
JOURNAL OF MEDICAL RESEARCH EFFECTIVENESS OF ORTHOGNATHIC SURGERY AND THE SUITABILITY WITH VIETNAMESE HARMONIOUS FACES IN CLASS III MALOCCLUSION PATIENTS Nguyen Hoang Minh¹, Pham Hoang Tuan2, Hoang Thi Doi3, Nguyen Thi Thu Phương1, Le Van Son1 ¹ School of Odontostomatology, Hanoi Medical University ²Hanoi National Hospital of Odontostomatology Hanoi Medical College Class III malocclusion affects negatively on health, quality of life and psychology Orthodontic and orthognathic surgery is necessary for adult patients with skeletal class III malocclusion to achieve good function and aesthetic The subjects were 35 patients at Hanoi National Hospital of Odontostomatology, Viet Duc University Hospital, and Hong Ngoc Hospital from April 2017 to September 2018 This was a quasi-experimental study with self- comparison, month, months and 12 months follow up Orthognathic surgery pushed maxilla forward and set back the mandible, corrected occlusion to skeletal class I intermaxilla reduced mental prognathism, corrected cross bite, dental decompensation The relationship among upper and lower lips with nose and chin were aesthetically improved Twenty patients, which were followed up after 12 months, had stable post-operation results In comparision with harmonious facial index of Kinh ethnic in Vietnam, 80% patients achieved skeletal harmony, 85% patients achieved dental harmony and 80% achieved soft tissue harmony, 100% patients had quality of life improved The more harmonious index patients acquired, the higher quality of life they achieved In order to improve surgical effectiveness, harmonious facial index is essential in planning and pre-surgical simulation Keywords: class III malocclusion, orthognathic surgery, harmonious faces I INTRODUCTION Malocclusion is the incorrect dental relation between teeth of two arches The rate of malocclusion is high, over 50% worldwide In America and Asian Corresponding author: Nguyen Hoang Minh, School of Odontostomatology, Hanoi Medical University Email: drnguyenhoangminh@gmail.com Received: 27/11/2018 Accepted: 15/03/2019 JMR 118 E4 (2) - 2019 countries, this rate can be as high as 70% [1] Class III malocclusion comprises a high percentages in the population, up to 35% [2; 3] Class III malocclusion is the etiology of occlusal trauma, functional decrease, and an increased risk of dental diseases, facial aesthetic and psychological problems [4] Treatment for skeletal class III malocclusion is quite necessary to improve quality of life [5] Most of adult patients with skeletal malocclusion, especially 43 JOURNAL OF MEDICAL RESEARCH class III malocclusion, need a combination of orthodontic and surgerical treatment to achieve good outcomes in function and aesthetic [6] However, treatment for skeletal malocclusion is always a challenge for orthodontists and surgeons Maxillary Lefort I osteotomy and bilateral sagittal split osteotomy ramus are commonly applied worldwide, providing good outcome in aesthetic and function in three dimensions, as well as post operative stability [7; 8] Domestic longitudinal studies on orthognathic surgery for patients with skeletal class III malocclusion is very limited The Vietnamese harmonious facial index is an important factor in assessing the effectiveness of surgery; hence, the application of this index in orthognathic surgery must be calculated Thus, we conducted this study with two objectives: To evaluate the effectiveness and stability of orthognathic surgery in class III malocclusion patients To evaluate the suitability with the Vietnamese harmonious facial index and satisfaction in skeletal class III malocclusion orthognathic patients II Method Subjects Skeletal class III malocclusion patients were treated with preoperative orthodontic and orthognathic surgery in Hanoi (Hanoi National Hospital of Odontostomatology, Viet Duc University Hospital and Hong Ngoc Hospital) from April 2017 to September 2018 44 Study method Quasi-experimental study with self comparison before operation (T0) and after operation at point in time month (T1), months (T6) and 12 months (T12) follow up; sample size: N=34 (p = 0.722 in sample size formula) At the moment, 35 patients have been followed up for month, 32 patients have been followed up for months and 20 patients have been followed up for 12 months Other patients are still followed up Before operation, all patients were examined, took cephalometric Xrays All patients were operated with maxillary Lefort I osteotomy and bilateral sagittal split ramus osteotomy Following and evaluating the effectiveness and stability of orthognathic surgery in class III malocclusion patients Result assessment after month (T1), months (T6) and 12 months (T12): clinical examination, cephalometric index measurement, (skeletal, dental and soft tissue index) Evaluating the effectiveness of surgery is evaluation the changes in facial index before and after surgery by comparing skeletal, dental and soft tissue index in preoperation (T0) and month postoperation (T1) Evaluating the stability of surgery is evaluation the changes in facial index through time after surgery by comparing skeletal, dental and soft tissue index in month postoperation (T1) and month postoperation (T6) and 12 month postoperation (T12) JMR 118 E4 (2) - 2019 JOURNAL OF MEDICAL RESEARCH Assessment of the suitability with Vietnamese harmonious facial index in skeletal class III malocclusion patients Assess the suitability with Vietnamese harmonious facial index is assess the suitability between postoperation facial index and Vietnamese harmonious facial index by comparing patients’ cephalometric indexs after 12 month postoperation with Vietnamese Kinh Ethnic harmonious facial index in National Research in School of Odonto & Stomatology – Hanoi Medical University Assessment of patient satisfaction after orthognathic surgery correcting class III malocclusion Orthognathic Quality of Life Questionnaire (OQLQ) was used to evaluate patients’ quality of life and satisfaction [9] Average index: ≤ 2: good quality of life; 2-3: moderate quality of life; ≥ 3: poor quality of life Data analysis Continuous variables were skeletal, dental and soft tissue index (SNA, SNB, ANB angle, A-V, B-V, Pg-V, Wits, over jet, over bite, U1-SN, Is-V, L1-MP, Ii-V, Li-E, LsE, Cm - Sn – Ls angle, Li - B' - Pg' angle, Ns - Sn - Pg’ angle) measured in Cephalometric X – rays which were analysed with SPSS JMR 118 E4 (2) - 2019 16.0 software If the variables achieved normal distribution, pair T - test was used If the variables cannot achieved normal distribution, non-parametric test (Wilcoxon signed rank test) was used Ethical Considerations This study belongs to National research of School of Odonto & Stomatology – Hanoi Medical University, which had been approved this study according to Decision No 202/HĐĐĐĐHYHN, signed on October 20th 2016 III Results Clinical and X-ray characteristics of class III malocclusion orthognathic patients 1.1 Clinical characteristics There were 14 male patients (40%); 21 female patients (60%) in the study with 100 % concave profile There were twenty one long facial cases (60%) and 14 mesofacial cases (40%) No short facial case were observed The average overjet was -4 ± 2.16 mm and the average overbite was 1.49 ± 0.66 mm 1.2 X-ray characteristics 45 JOURNAL OF MEDICAL RESEARCH Table Skeletal – dental – soft tissue index on cephalometric by gender Index X ± XD P (Male – Female) Male (N = 14) Female (N = 21) SNA (degree) 82.59 ± 4.54 79.78 ± 2.83 > 0.05 SNB (degree) 87.69 ± 4.43 83.17 ± 2.87 < 0.01 ANB (degree) -5.09 ± 3.22 -3.39 ± 1.76 > 0.05 Wits (mm) -11.90 ± 4.58 -9.83 ± 2.68 > 0.05 U1 - SN (degree) 114.05 ± 9.55 108.13 ± 8.07 > 0.05 L1 - MP (degree) 85.05 ± 11.13 88.13 ± 6.73 > 0.05 Li - E (mm) 4.38 ± 1.27 3.12 ± 0.75 < 0.01 Ls - E (mm) -2.81 ± 2.19 -3.17 ± 1.31 > 0.05 Cm - Sn - Ls (degree) 73.37 ± 12.30 87.66 ± 13.18 < 0.01 Li - B’ - Pg’ (degree) 147.10 ± 10.29 146.10 ± 11.61 > 0.05 Ns - Sn - Pg’ (degree) 186.43 ± 2.90 184.78 ± 3.56 > 0.05 Comment: Small SNA, large SNB , negative ANB, negative Wits Maxillary retrognathism, mandibular prognathism Small Ls – E retrognathic upper lip, large Li – E prognathic lower lip Acute nasolabial angle (Cm – Sn – Ls) Obtuse labiomental angle (Li – B’ – Pg’) Large facial angle (Ns – Sn – Pg’) featured for concave profile The differences of SNB, Li-E, Cm-Sn-Ls were statistically significant between males and females Effectiveness and stability after orthognathic surgery in class III malocclusion patients 2.1 Skeletal, dental and soft tissue index in month postoperation 46 JMR 118 E4 (2) - 2019 JOURNAL OF MEDICAL RESEARCH Table Skeletal, dental and soft tissue index month posoperation (T1) in comparision with preoperation (T0) Index T0 (N = 35) T1 (N = 35) P (T0 – T1) X SD X SD SNA (degree) 80.90 3.82 84.19 3.37 < 0.001 A - V (mm) 60.50 5.34 64.10 5.17 < 0.001 SNB (degree) 84.97 4.17 81.56 3.66 < 0.001 B - V (mm) 65.41 7.79 60.75 7.75 < 0.001 Pg - V (mm) 66.27 9.32 61.47 9.20 < 0.001 ANB (degree) -4.07 2.55 2.61 1.51 < 0.001 Wits (mm) -10.66 3.65 0.04 2.71 < 0.001 Overjet (mm) -4.00 2.16 2.43 0.66 < 0.001 Overbite (mm) 1.49 0.66 1.66 0.54 > 0.05 U1 - SN (degree) 110.50 9.05 105.50 9.64 < 0.001 Is - V (mm) 67.20 7.34 69.87 6.93 < 0.001 L1 - MP (degree) 86.90 8.74 97.03 4.66 < 0.001 Ii - V (mm) 71.43 8.02 66.96 6.95 < 0.001 Li - E (mm) 3.62 1.16 1.85 0.88 < 0.001 Ls - E (mm) -3.03 1.69 0.13 0.79 < 0.001 Cm - Sn - Ls (degree) 81.94 14.51 92.56 4.29 < 0.001 Li - B’ - Pg’ (degree) 146.50 10.96 134.19 5.23 < 0.001 Ns - Sn - Pg’ (degree) 185.44 3.37 164.95 2.62 < 0.001 Comment: Forward movement of the maxilla (SNA, A-V increased), backward movement of the mandible, prognathic chin reduced (SNB, B-V, Pg-V reduced) Class I intermaxillary relationship was achieved, cross bite was corrected Forward movement of upper incisors (Is-V increased), backward movement of lower incisors (Ii-V decreased) Increased angle between lower incisors and mandibular plane (L1-MP), decreased angle between upper incisors and cranial plane (U1-SN) Forward movement of upper lip (Ls-E increased), backward movement of lower lip (Li-E decreased), facial angle decreased (Ns-Sn-Pg’) Nasolabial angle was larger (Cm-Sn-Ls increased) and labiomental angle was smaller (Li – B’ – Pg’ decreased) in comparision with pre-surgery index Above changings were statistically significant (p < 0.05) Overbite changing is not statistically significant (p > 0.05) JMR 118 E4 (2) - 2019 47 JOURNAL OF MEDICAL RESEARCH 2.2 Skeletal, dental and soft tissue index in month postoperation Table Skeletal, dental and soft tissue index in month postoperation (T6) in comparision with month postoperation (T1) T1 (N = 32) T6 (N = 32) X SD X SD P (T1 - T6) SNA (degree) 82.99 3.25 82.83 2.64 > 0.05 A - V (mm) 63.67 5.19 62.94 4.66 > 0.05 SNB (degree) 80.42 3.53 81.42 3.15 < 0.01 B - V (mm) 60.37 7.94 62.60 7.20 < 0.001 Pg - V (mm) 61.13 9.47 63.17 8.50 < 0.01 ANB (degree) 2.56 1.54 1.41 1.19 < 0.01 Overjet (mm) 2.44 0.67 2.00 0.36 < 0.01 Overbite (mm) 1.62 0.55 1.56 0.50 > 0.05 U1 - SN (degree) 105.10 9.79 106.54 8.57 > 0.05 Is - V (mm) 69.33 7.01 69.01 6.38 > 0.05 L1 - MP (degree) 96.85 4.81 95.89 3.13 > 0.05 Ii - V (mm) 66.43 7.03 66.76 6.37 > 0.05 Li - E (mm) 1.84 0.90 1.34 1.61 < 0.05 Ls - E (mm) 0.13 0.81 -0.12 1.54 > 0.05 Cm - Sn - Ls (degree) 92.30 4.26 96.36 4.60 < 0.001 Li - B’ - Pg’ (degree) 133.89 5.33 129.22 4.51 < 0.01 Ns - Sn - Pg’ (degree) 165.17 2.63 166.59 2.62 < 0.001 Index Comment: Changing in maxillary index (SNA, A - V) was not statistically significant (p > 0.05) Forward movement of mandible and chin (SNB, B-V, Pg-V increased) (p < 0.05) Reduction of ANB angle was statistically significant, class I intermaxillary relationship Overjet was statistically significantly decreased (p < 0.05), changing in overbite and dental index (U1 - SN, Is - V, L1 - MP, Ii - V) were not statistically significant (p > 0.05) Upper and lower lips were set back E-line Facial angle (Ns - Sn - Pg’) was increased Larger nasolabial angle (Cm - Sn - Ls increased), smaller labiomental angle (Li - B' - Pg' decreased) in comparision with pre-surgery Those changings were statistically significant (p < 0.05) 48 JMR 118 E4 (2) - 2019 JOURNAL OF MEDICAL RESEARCH 2.3 Skeletal, dental and soft tissue index in 12 month postoperation Table Skeletal, dental and soft tissue index in 12month postoperation (T12) in comparision with month postoperation (T6) T6 (N = 20) T12 (N = 20) X SD X SD P (T6 - T12) SNA (degree) 82,83 2,99 82,71 3,36 > 0,05 A - V (mm) 63,81 4,75 63,65 4,89 > 0,05 SNB (degree) 81,44 3,55 81,66 3,82 > 0,05 B - V (mm) 63,33 7,67 63,48 6,53 > 0,05 Pg - V (mm) 63,79 9,10 63,94 8,66 > 0,05 ANB (degree) 1,39 1,18 1,05 1,02 > 0,05 Overjet (mm) 2,05 0,39 2,10 0,31 > 0,05 Overbite (mm) 1,55 0,51 1,60 0,50 > 0,05 U1 - SN (degree) 107,29 9,62 107,44 8,67 > 0,05 Is - V (mm) 69,78 6,81 69,91 6,74 > 0,05 L1 - MP (degree) 95,11 3,43 94,82 3,73 > 0,05 Ii - V (mm) 67,59 6,78 67,23 6,52 > 0,05 Li - E (mm) 1,46 1,80 1,47 2,23 > 0,05 Ls - E (mm) -0,03 1,75 -0,18 1,81 > 0,05 Cm - Sn - Ls (degree) 94,04 3,52 94,22 4,02 > 0,05 Li - B’ - Pg’ (degree) 132,47 4,31 133,79 7,87 > 0,05 Ns - Sn - Pg’ (degree) 166,72 2,88 167,43 3,55 > 0,05 Index Comment: Skeletal, dental and soft tissue index in 12 month postoperation was similar to month postoperation index (p > 0.05) The suitability with Vietnamese harmonious facial index and satisfaction in skeletal class III malocclusion orthognathic patients 3.1 The suitable rate with Vietnamese harmonious facial index JMR 118 E4 (2) - 2019 49 JOURNAL OF MEDICAL RESEARCH Figure Suitable rate with Vietnamese harmonious facial index Comment: Among 20 patients got 12 month postoperative following up, there were 16 cases having harmonious skeletal index (80%), 17 cases having harmonious dental index (85%) and 16 cases having harmonious soft tissue index (80%) Four cases that did not achieve the harmonious skeletal, also fail to achieve the harmonious soft tissue index 3.2 Quality of life changing after surgery Figure Quality of life changing after surgery Comment: There was no good quality of life case before surgery Quality of life was improved after surgery, there were 17 cases having good quality of life (85%), cases having moderate quality of life (15%) and there was no case having poor quality of life 3.3 The suitability between quality of life (QoL) and harmonious face after surgery 50 JMR 118 E4 (2) - 2019 JOURNAL OF MEDICAL RESEARCH Figure Quality of life and harmonious face Comment: 100% cases had good quality of life in group harmonious face achieved Among cases that could not achieve the harmonious face, there were patients having moderate quality of life and patient having good quality of life The relation between harmonious face and quality of life was statistically significant (p < 0.01) IV Discussion Clinical and X-ray characteristics in skeletal class III orthognathic patients In our study, proportion of females (60%) was higher than males (40%) due to the fact that females are more concerned about aesthetic than males Index measured on cephalometrics suggested retrognathism maxilla, prognathism mandible, dental compensation (lingual inclination of lower incisors, labial inclination of upper incisors), retrognathism upper lip and prognathism lower lip, acute nasolabial angle, obtuse labiomental angle, large facial angle These results were appropriate with studies conducted by Aydemir [7], Le Tuan Hung [10], I-Ming Tsai [11] Remarkablely negative ANB and Wits, which suggested large deviation in anterior-posterior dimension between maxilla and mandible These are characteristics of patients who need orthognathic surgery JMR 118 E4 (2) - 2019 Effectiveness and orthognathic surgery malocclusion stability after in class III month postoperation, our study observed forward movement of the maxilla, backward movement of the mandible and intermaxillary relationship was changed from class III (preoperation) to class I Overjet was increased to positive average value, cross bite was corrected The angle between lower incisors and mandibular plane was increased, the angle between maxillary incisors and basal plane was decreased, dental decompensation was achieved (palatal inclination of upper incisors and labial inclination of lower incisors), dental esthetic was improved Soft tissue was also changed: forward movement of upper lip, backward movement of lower lip, decreasing facial angle, increasing nasolabial angle as well as decreasing labiomental angle in comparion with preoperation These changes significantly improved facial 51 JOURNAL OF MEDICAL RESEARCH aesthetic, the relationship between upper lip and nose, lower lip and chin Our result was appropriate with studies conducted by Ghassemi, Le Tan Hung, I-Ming Tsai [8; 10; 11] At month postoperation, the maxilla was stable The mandible was unstable, which moved forward, reducing overjet However, the intermaxillary relationship was still class I, and positive overjet value remained Ghassemi, Le Tan Hung and I-Ming Tsai also observed unstable mandible after surgery [8; 10; 11] This unstable condition was due to traction of muscle underneath the mandible, excessive backward movement of the condyle in fossa, changing in direction and force of the masseter muscle and pterygoid muscle, which caused a force pulling the gonial upward and forward [12] About soft tisse, higher esthetic relationship among nose, lips and chin was achieved (less acute nasolabial angle and less obtuse labiomental angle), which may be due to completely disappearance of swollen situation in comparision with 1-month after surgery 20 patients who had been followed up 12 months had stable skeletal, dental and soft tissue index Other patients will be followed up till 12-month after surgery The suitability with Vietnamese harmonious facial index and satisfaction in skeletal class III malocclusion orthognathic patients Among the 20 patients who completed 12-month follow-up, there were 16 cases having harmonious skeletal index (80%), 17 cases having harmonious dental index (85%) and 16 cases having har monious 52 soft tissue index (80%) Patients who had harmonious skeletal index also had harmonious soft tisse index Thus, skeletal index is important, which need to achieved in planning to help creating harmonious soft tissue index because it is difficult to predict accurately soft tissue index while planning Dental decompensation, less acute nasolabial angle, less obtuse labiomental angle, decreasing facial angle helps improving facial esthetic significantly After surgery, the quality of life had been raised, and patients were satisfied with their facial changing, which was similar to studies of Wee [13] The more harmonious index achieved, the better quality of life those patients acquired Therefore, harmonious facial index should be applied in planning and preoperative simulation to increase surgical effectiveness and patient’s quality of life V Conclusion Maxillary Lefort I osteotomy and bilateral sagittal split ramus osteotomy were efficient in correcting skeletal class III malocclusion After surgery, the maxilla moved forward, the mandible moved backward, class I intermaxillary relationship was achieved, as well as backward movement of chin, correction of cross bite and dental decompensation (palatal inclination of upper inciors and labial inclination of lower incisors), thus esthetic was significantly improved Forward movement of upper lip, backward movement of lower lip, decrease of facial angle, increase of nasolabial angle as well as decrease of labiomental angle, JMR 118 E4 (2) - 2019 JOURNAL OF MEDICAL RESEARCH harmonious relationship among nose, lips and chin were successfully achieved after surgery 6-month postoperation, the mandible was unstable and moved forward 12-month postoperation, outcomes of 20 patients being followed up were stable After surgery, the quality of life had been raised, and patients were satisfied with their facial changing The more harmonious index achieved, the better quality of life those patients acquired Therefore, harmonious facial index should be applied in planning and preoperative simulation to increase surgical effectiveness Acknowledgment We would like to express our sincere gratitude to volunteers for their participation in our study, as well as Hanoi National Hospital of Odontostomatology, Viet Duc Hospital, Hong Ngoc Hospital, School of Odonto & Stomatology – Hanoi Medical University, Assoc.Prof PhD Truong Manh Dung – head of National Research project, Assoc.Prof PhD Vo Truong Nhu Ngoc REFERENCES Carvalho F.S.D (2014) Epidemiology of malocclusion in children and adolescents: a critic review Rev Gaúch Odontol, Porto Alegre, 62, 253 - 260 Hardy D.K Cubas.Y.P., Orellana.M.F (2012) Prevalence of angle class III malocclusion: A systematic review and meta-analysis Open Journal of Epidemiology, 2, 75 - 82 Hoàng Việt Hải, Đỗ Quang Trung (2011) Mối liên quan độ nghiêng trục JMR 118 E4 (2) - 2019 thân nanh với loại khớp cắn Tạp chí nghiên cứu Y học, 75, 95 - 99 Nicodemo D., PereiraM.D., Ferreira.L.M (2008) Self-esteem and depression in patients presenting angle class III malocclusion submitted for orthognathic surgery Med Oral Patol Oral Cir Bucal, 13, 48 - 51 Huang S., ChenW., Ni Z et al (2016) The changes of oral health-related quality of life and satisfaction after surgeryfirst orthognathic approach: a longitudinal prospective study Head & Face Medicine, 12, - Larson B.E (2014) Orthodontic Preparation for Orthognathic Surgery Oral Maxillofacial Surg Clin N Am, 26, 441 – 458 Aydemir H., Memikoglu U.T (2015) Facial Soft Tissue Changes in Class III Patients Treated With Bimaxillary, Maxillary Advancement or Mandibular Set Back Orthognathic Surgery OHDM, 14, 75 - 80 Ghassemi M., Ghassemi A., Showkatbakhsh R et al (2014) Evaluation of soft and hard tissue changes after bimaxillary surgery in class III orthognathic surgery and aesthetic consideration Natl J Maxillofac Surg, 5, 157 - 160 Miguel J.A.M., Palomares N.B., Feu D (2014) Life-quality of orthognathic surgery patients: The search for an integral diagnosis Dental Press J Orthod, 19, 123 - 137 10 Lê Tấn Hùng, Nguyễn Tài Sơn (2014) Đánh giá hiệu xoay phức hợp hàm – hàm chiều kim đồng 53 JOURNAL OF MEDICAL RESEARCH hồ điều trị lệch lạc xương hàm loại III Tạp chí Y dược lâm sàng 108, (2), 67 - 73 11 I-Ming T., Chen-Hui L., Yu-Ching W (2012) Correction of skeletal Class III alocclusion with clockwise rotation of the maxillomandibular complex Am J Orthod Dentofacial Orthop, 141(2), 2192-2227 12 Aydemir 54 H., Efendiyeva R., Karasu H., et al (2015) Evaluation of longterm soft tissue changes after bimaxillary orthognathic surgery in Class III patients Angle Orthod, 85 (4), 631- 637 13 Wee T H., Poon C.Y (2014) Quality of Life Treatment Outcomes of Class III Skeletal Patients after Bimaxillary Osteotomies Proceedings of Singapore Healthcare, 23(3), 183 -190 JMR 118 E4 (2) - 2019 ... orthognathic surgery in class III malocclusion patients To evaluate the suitability with the Vietnamese harmonious facial index and satisfaction in skeletal class III malocclusion orthognathic patients. .. dental and soft tissue index) Evaluating the effectiveness of surgery is evaluation the changes in facial index before and after surgery by comparing skeletal, dental and soft tissue index in preoperation... skeletal class III malocclusion patients Assess the suitability with Vietnamese harmonious facial index is assess the suitability between postoperation facial index and Vietnamese harmonious facial index