The Influence of Paranasal Augmentation on the Measurement of the Nose for the Treatment of Midfacial Concavity

The Influence of Paranasal Augmentation on the Measurement of the Nose for the Treatment of... Abstract Background A concave midface with its associated deep nasolabial folds is more aesthetically displeasing than a convex midface. Midfacial concavity may be addressed with autologous tissue and implants. Objectives The aim of this study was to determine the effect of paranasal augmentation on photogrammetric parameters. Methods Between July 2013 and August 2016, 12 patients underwent paranasal augmentation to address midface concavity. Augmentation was performed with autologous rib cartilage, autologous mandibular bone, or preshaped porous polyethylene (PPE). All operations were performed through the upper gingivobuccal approach. Twelve patients who underwent malar reduction using the same approach acted as a control group to account for the influence of the approach on soft tissue change. Preoperative and postoperative measurements were made photogrammetrically. Results The average follow-up period was 12.8 months (range, 5-30 months) for both groups. The mean thickness of augmentation grafts was 5.18 mm (range, 3-7 mm). Alar width and alar base width increased 4.84% (P = 0.01) and 7.66% (P = 0.01), respectively. The nasolabial angle increased from 97.2°to 103.6° and the columellar inclination increased from 116.0° to 119.1° but neither were statistically significant. Photogrammetric parameters did not change significantly in the control group. Partial wound dehiscence occurred in one case. There was greater postoperative increase in alar width (P = 0.020), alar base width (P = 0.024), and nasolabial angle (P = 0.033) in the experimental group compared to the control group. Conclusions Paranasal augmentation using PPE or autologous material generates measurable soft tissue changes designed to enhance paranasal aesthetics. Level of Evidence: 3 Midface concavity may be aesthetically displeasing and accelerate the appearance of facial aging.1,2 Patients with paranasal volume deficiency and localized concavity present with a flattened facial profile, compressed nasolabial angle, and deepening of furrows around the nose and mouth.2,3 Improvement of paranasal deficiency can be achieved by malar osteotomy, Le Fort I osteotomy, or both.3 When there is paranasal deficiency and a normally positioned maxilla,2 augmentation of the depressed area can camouflage the paranasal deficiency. This is accomplished with autogenous bone graft or alloplastic materials.2 The influence of paranasal augmentation on the surrounding soft tissue envelope remains unclear. Factors like incision placement, plane of dissection, wound closure technique, and scar formation are expected to influence the aesthetic outcome. The aim of this study was to determine the effect of paranasal augmentation on photogrammetric measurements. By comparing these changes with a control group, we controlled for the impact of the surgical approach on the outcome. To our knowledge, this is the first series about paranasal augmentation that compares an experimental group and a control group. METHODS This retrospective study was performed at Chang Gung Memorial Hospital after obtaining approval from the Institutional Review Board. Between July 2013 and August 2016, twenty-one patients with midface convexity and paranasal volume deficiency underwent paranasal augmentation for correction of midface concavity. Patients were included if they presented with acceptable occlusion and did not warrant orthognathic surgery, and did not have fat graft or filler injection. Informed consent was obtained for all patients. Nine patients who underwent simultaneous rhinoplasty were excluded. In the twelve remaining patients, paranasal augmentation was achieved using autologous rib cartilage (n = 1), autologous bone from the mandibular angle (n = 1), and preshaped porous polyethylene (PPE, Medpor, Stryker, Kalamazoo, MI, n = 10). All operations were performed under general anesthesia. Bilateral upper gingivobuccal sulcus incisions were used, lateral to the pyriform aperture, above the root of the central incisor to the canine eminence and 1 cm above the sulcus to provide an adequate cuff of mucosa for wound closure.4 The incisions did not connect at the midline and subperiosteal dissection was conservative. Autogenous and alloplastic grafts were contoured to adapt to the depressed recipient site5 and trimmed along the margin of the canine root to avoid iatrogenic injury during fixation. The graft edges were contoured to the recipient bone for a more natural contour. PPE was soaked in an antibiotic solution with negative pressure.2 Using a syringe, an air-tight seal was created with a gloved finger, and the plunger was withdrawn to create a near vacuum.2 After the shape and position of the autogenous graft or PPE was confirmed, grafts and implants were secured with an 8-mm or 10-mm miniscrew centrally. Special attention was taken to avoid injury to the tooth root (Figure 1). A 3-0 nylon alar cinch suture was placed between transverse nasalis muscles at the alar-facial junction and the overlying mucosa was closed with absorbable sutures. Drains were not placed. The surgical procedure is demonstrated in the video (available online as Supplementary Material at www.aestheticsurgeryjournal.com). Figure 1. View largeDownload slide A 36-year-old woman with intraoperative view of paranasal PPE implants fixed with miniscrews. Figure 1. View largeDownload slide A 36-year-old woman with intraoperative view of paranasal PPE implants fixed with miniscrews. Video 1 Watch now at https://academic.oup.com/asj/article-lookup/doi/10.1093/asj/sjx166 Video 1 Watch now at https://academic.oup.com/asj/article-lookup/doi/10.1093/asj/sjx166 Close Twelve consecutive patients who underwent malar reduction through the same approach, using an alar cinch suture and identical wound closure technique, acted as a control group. This was intended to control for the effect of the gingivobuccal incision, subperiosteal dissection plane, and wound closure technique on soft tissue change. We used standardized photogrammetric methodology and efforts were made to ensure true profile views were obtained by the use of paper tape at 0°, 45°, 90°, 135°, and 180°, with the camera lens at 90° from a rotating stool. Patients were asked to look straight ahead with eyes in neutral position.5 In both groups, alar width, alar base width, tip projection, nasolabial angle, and columellar inclination were measured pre- and postoperatively with previously described photogrammetric methodology using the Adobe Photoshop CS6 measure tool (Adobe Systems, Inc., San Jose, CA).4,5 All measurements were performed by the same investigator (C.I.Y.). The definitions of the parameters are given in Table 1 and Figure 2. The augmentation and control group were compared. Table 1. Definitions of Linear and Angular Parameters Parameter   Definition   Alar width  Distance between the most lateral part of bilateral alar wings  Alar base width  Distance between bilateral alar base  Tip projection  Distance between tip to coronal plane  Nasolabial angle  Angle of columellar-subnasale-labrale superius  Columellar inclination  Angle of coronal plane to columellar-subnasale  Coronal plane  The plane perpendicular to Frankfort horizontal plane and passed the most-protruding part of pupil  Parameter   Definition   Alar width  Distance between the most lateral part of bilateral alar wings  Alar base width  Distance between bilateral alar base  Tip projection  Distance between tip to coronal plane  Nasolabial angle  Angle of columellar-subnasale-labrale superius  Columellar inclination  Angle of coronal plane to columellar-subnasale  Coronal plane  The plane perpendicular to Frankfort horizontal plane and passed the most-protruding part of pupil  View Large Figure 2. View largeDownload slide A 36-year-old woman with (A) Linear measurement in this study: alar width, alar base width. (B) tip projection (A-B distance). Angular measurements in this study: nasolabial angle (angle of C-D-E, collumellar-subnasale-labrale superius), columellar inclination (angle of C-D (columellar-subnasale) to coronal plane). Figure 2. View largeDownload slide A 36-year-old woman with (A) Linear measurement in this study: alar width, alar base width. (B) tip projection (A-B distance). Angular measurements in this study: nasolabial angle (angle of C-D-E, collumellar-subnasale-labrale superius), columellar inclination (angle of C-D (columellar-subnasale) to coronal plane). For subjective outcome assessment, we utilized a simple questionnaire (Appendix A, available online as Supplementary Material at www.aestheticsurgeryjournal.com). composed of three questions that measured the degree of satisfaction of the aesthetic outcome and soft tissue change. We performed the questionnaire by telephone interview by the same investigator (a research assistant). For each question, the patient assigned a score from 1 to 5, where higher scores indicated greater satisfaction. Average scores for each question were calculated. Statistical Analysis Statistical analyses were performed using SPSS package version 20.0 for Windows. Statistical differences were evaluated by the analysis of variance test with Mann-Whiney test and paired ttest. P values of less than 0.05 were considered statistically significant. RESULTS Table 2 summarizes the demographics of the paranasal augmentation group. There were 2 men and 10 women with a mean age of 32.5 years (range, 18-50 years). In the control group, there were 2 men and 10 women with a mean age of 32.8 years (range, 25-48 years). There was no significant change with all the parameters (P > 0.05) after upper gingivobuccal incision for malar reduction. Table 2. Demographics and Characteristics of Augmentation Group No.  Sex  Age (years)  Material  Thickness (mm)  Follow up (months)  Complication  1  F  37  Medpor  6  6  —  2  M  28  Medpor  7  16  —  3  F  18  Medpor  4.5  17  —  4  F  36  Medpor  3  10  —  5  F  50  Medpor  6  13  —  6  F  23  Medpor  4.5  5  Wound dehiscence  7  F  39  Medpor  7  6  —  8  M  31  Medpor  4.5  8  —  9  F  32  Rib  5  27  —  10  F  30  Medpor  4.5  7  —  11  F  32  Mandible angle  4  30  —  12  F  33  Medpor  6  8  —  No.  Sex  Age (years)  Material  Thickness (mm)  Follow up (months)  Complication  1  F  37  Medpor  6  6  —  2  M  28  Medpor  7  16  —  3  F  18  Medpor  4.5  17  —  4  F  36  Medpor  3  10  —  5  F  50  Medpor  6  13  —  6  F  23  Medpor  4.5  5  Wound dehiscence  7  F  39  Medpor  7  6  —  8  M  31  Medpor  4.5  8  —  9  F  32  Rib  5  27  —  10  F  30  Medpor  4.5  7  —  11  F  32  Mandible angle  4  30  —  12  F  33  Medpor  6  8  —  View Large The average thickness of Medpor, rib, and bone used for augmentation was 5.18 mm (range, 3 mm to 7 mm). The alar width and alar base width increased 4.84% (P = 0.010) and 7.66% (P = 0.010) postoperatively. Tip projection increased 7.77% (P = 0.462) after paranasal augmentation. The nasolabial angle increased from 97.2° to 103.6°. The average increase was 6.4° (range, 1°-20°) but the change was not significant (P = 0.068). Columellar inclination increased from 116.0° to 119.1°. The average increase was 3.08° (range, 2°-17°) but the difference was not significant. The postoperative increase in alar width (P = 0.020), alar base width (P = 0.024), and nasolabial angle (P = 0.033) was greater in the augmentation group compared to the control group (Table 3). Table 3. Measurements of Midface Soft Tissue Change Between Augmentation Group and Control Group (statistically significant at *P < 0.05, data presented as mean ± standard deviation)   Control group, N = 12   Augmentation group, N = 12   P value   Preoperative  Postoperative  P value  Preoperative  Postoperative  P value  Age (years)  32.45 ± 8.5  —  —  32.83 ± 7.2  —  —  0.644  Alar width  172.2 ± 39.0  173.64 ± 39.7  0.218  209.6 ± 41.0  216.8 ± 42.7  0.010*  0.020 *  Alar base width  111.6 ± 21.2  112.5 ± 21.3  0.054  116.3 ± 34.3  126.1 ± 36.7  0.010 *  0.024 *  Tip projection  55.2 ± 13.6  54.6 ± 13.0  0.543  109.0 ± 46.4  113.8 ± 36.3  0.462  0.309  Nasolabial angle (°)  98.6 ± 10.4  97.3 ± 8.5  0.788  97.2 ± 16.0  103.6 ± 15.3  0.068  0.033 *  Columellar inclination (°)  110.2 ± 6.9  108.5 ± 8.4  0.834  116.0 ± 16.1  119.1 ± 13.8  0.243  0.156    Control group, N = 12   Augmentation group, N = 12   P value   Preoperative  Postoperative  P value  Preoperative  Postoperative  P value  Age (years)  32.45 ± 8.5  —  —  32.83 ± 7.2  —  —  0.644  Alar width  172.2 ± 39.0  173.64 ± 39.7  0.218  209.6 ± 41.0  216.8 ± 42.7  0.010*  0.020 *  Alar base width  111.6 ± 21.2  112.5 ± 21.3  0.054  116.3 ± 34.3  126.1 ± 36.7  0.010 *  0.024 *  Tip projection  55.2 ± 13.6  54.6 ± 13.0  0.543  109.0 ± 46.4  113.8 ± 36.3  0.462  0.309  Nasolabial angle (°)  98.6 ± 10.4  97.3 ± 8.5  0.788  97.2 ± 16.0  103.6 ± 15.3  0.068  0.033 *  Columellar inclination (°)  110.2 ± 6.9  108.5 ± 8.4  0.834  116.0 ± 16.1  119.1 ± 13.8  0.243  0.156  View Large There were no complications including hematoma, infection, implant extrusion, or implant migration during the follow-up period of 12.8 months (range, 5 months to 30 months). Only one patient had partial intraoral wound dehiscence and recovered after aggressive oral hygiene and limited debridement with wound repair two weeks later. During the follow-up period, no patient complained about foreign body sensations over the paranasal region, nasal floor, lateral nasal linings, or gingival area. Nor did any patient suffer from airway obstruction. There were no visible or palpable stepoffs. All patients were all satisfied with the aesthetic outcome and improved soft tissue change in paranasal and nasal area, with average satisfaction scores of 4.5 (range, 4-5), 4.6 (range, 4-5), and 4.5 (range, 3-5) out of 5, respectively. Figures 3 and 4 compare these changes in the control group and augmentation group. Figure 3. View large Download slide View large Download slide A 38-year-old woman in the control group with (A, C, E, G, I, K) preoperative and (B, D, F, H, J, L) 12-month postoperative outcomes. Figure 3. View large Download slide View large Download slide A 38-year-old woman in the control group with (A, C, E, G, I, K) preoperative and (B, D, F, H, J, L) 12-month postoperative outcomes. Figure 4. View large Download slide View large Download slide A 30-year-old woman in the augmentation group with (A, C, E, G, I, K) preoperative and (B, D, F, H, J, L) 12-month postoperative outcome. Figure 4. View large Download slide View large Download slide A 30-year-old woman in the augmentation group with (A, C, E, G, I, K) preoperative and (B, D, F, H, J, L) 12-month postoperative outcome. DISCUSSION Paranasal augmentation is useful for correcting midfacial concavity without malocclusion.1,6,7 It can simulate the visual effects of skeletal osteotomies without affecting dental occlusion.1,8 It is an often useful adjunct to rhinoplasty, and can improve the soft tissue relationship between the perinasal and upper lip areas.7 Various methods are described for correction of paranasal volume deficiency.3 Autogenous bone graft is a dependable option for augmentation,9,10 but donor site morbidity must be considered, and the resorption of graft could generate unpredictable results.2,3 A sound understanding of the 3-dimensional (3D) anatomy and finesse is requisite for sculpting of the graft; this should be considered in less experienced hands.3 Alloplastic materials including porous polyethylene have resultantly gained widespread acceptance.2,6 PPE is strong, biocompatible, and allows for tissue ingrowth with resistance to infection. It is available in prefabricated shapes and sizes, is easy to shape, will not resorb, and there is no donor site morbidity.2,3,6,11,12 PPE implants have many craniofacial reconstructive applications12-15 and are associated with satisfactory outcomes. There is a deficiency of literature that quantifies the effect of paranasal augmentation on the soft tissue envelope. The studies that exist have used cone-beam computed tomography and lateral cephalograms to objectively measure soft tissue changes.2,3,6 The relationship between the thickness of paranasal implant and soft tissue change has been studied;2,6 the average increase in soft tissue outline in the peri-alar region is 68% to 80.7% of implant thickness.2,6 The focus of this study was not projection of the implant. Instead, the authors evaluated the photogrammetric changes of the paranasal region after augmentation. In this study, photogrammetry demonstrated that there is significant increase in alar width and alar base width and a trend toward nasolabial angle widening after augmentation. The effect was most profound along the upper lip subunit. Correction of midface hypoplasia was achieved by adding paranasal fullness, effacing prominent nasolabial grooves, and blunting the nasolabial angle. These changes are thought to contribute to a more youthful appearance and more attractive facial profile. The results from this series corroborated those from a similar study by Kwon et al.6 In that study, however, there was significant increase of columellar inclination whereas our results demonstrated no significant change. It is possible that variations in measurement methods or case numbers contributed to this distinction. The biggest difference between this series and other series in the literature is the study design. The authors compared soft tissue change in a paranasal augmentation group and a control group using the same incision, plane of dissection, and closure technique. This was designed to control for the possibility that disruption of the paranasal periosteum would influence the muscles near the alar base.6 Widening of the alar base is a known adverse outcome after Le Fort I advancement, even when V-Y closure is performed or alar base cinch suture is placed.6,16-19 Furthermore, it is reported that there is no significant correlation between soft tissue changes and maxillary advancement.20 Kim et al suggested that paranasal soft tissue changes could result from muscle and soft tissue tension.3,20,21 Clearly, there is no consensus on whether a vestibular incision with or without cinch suture influences the shape of the nose and paranasal soft tissue envelope. The effect of the surgical approach and wound closure on the soft tissue envelope warrants further study.2,3,6 To our knowledge, this study is the first to control for these changes, and to objectively quantify them in a control group. Indeed, the authors found that there is no significant change in alar width, alar base width, tip projection, nasolabial angle, and columellar inclination in the control group. Controlling for potential confounders allowed the authors to attribute changes in alar width, alar base width and nasolabial angle to paranasal augmentation alone. In patients with a normal profile, postsurgical alar and alar base widening are considered adverse outcomes. However, in patients with paranasal volume deficiency and midface concavity, said changes may contribute to a more youthful and attractive appearance.8 Changes in the upper lip and nose improves overall facial balance. In patients with midfacial concavity and excessive alar width, these relationships must be taken into consideration. In some cases, it may even be necessary to augment the paranasal region in addition to alar reduction. Alternatively, patients with preexisting alar narrowing such as overreduction of alar base, may benefit from additional alar widening. For these reasons, every patient must be evaluated individually. Thoughtful preoperative evaluation, guidance, and treatment planning is paramount to successful augmentation. The PPE implants used in this study are preshaped. They are crescentic and available in two sizes: 27 mm × 25 mm × 4.5 mm of projection, and 30 mm × 28 mm × 7 mm of projection.1,7 For unilateral cases, the contralateral side is used a reference to determine the thickness of augmentation grafts and tailored intraoperatively for symmetry. When there is bilateral concavity, the thickness is determined by the severity of concavity. The goal is to achieve a balance between midface volume correction, alar widening, and improved facial profile harmony. In the future, 3D simulation may guide surgical decision making to achieve more predictable outcomes. The soft tissue envelope and facial skeleton contribute to midface contour and convexity.8 Thus, soft tissue and skeletal augmentation may correct midfacial deficiency, but the influence of each component may vary from patient to patient. For example, fat grafting and injection of fillers may address soft tissue volume loss associated with aging where there is no need to augment skeletal projection.8 In such a patient, augmentation of the facial skeleton may project the midface, but augmentation of the soft tissue envelope will more effectively blunt the contours of the skeleton.6 When analyzing the face, clinicians should consider bony and soft tissue deficiencies independently.3 The patients presented in this series were young, and their paranasal volume deficiencies resulted more from skeletal deficiency than changes associated with aging. Midfacial concavity resulting from maxillary hypoplasia is more common in certain ethnic groups, including Asians and Blacks.1 The PPE is a dependable substitute for bone and cartilage in facial skeletal augmentation. Paranasal augmentation with PPE is straightforward and the result is long-lasting. In other series, the complication rate of PPE augmentation was 0.9% to 17.5%.6,11 In our series, the long-term complication rate was 0 and there were no explanted implants. One patient had partial wound dehiscence but recovered with aggressive oral hygiene and limited debridement and repair. There were no other early or late complications and all patients were satisfied with the aesthetic outcome. A major limitation of this study is the small sample size. In this series, it was difficult to determine a precise soft tissue response because the severity of volume deficiency varied, and the thickness of PPE and autograft were not standardized.6 The materials used were also not uniform, and resorption of grafts was not studied. Both patients with autologous grafts had the longest follow up in this series (30 months and 27 months), but the absorption rate warrants further evaluation in future studies. There were also limitations in the photogrammetric methodology. Conversion of a 3D object into two dimensions may limit the validity of the increases reported in this series by underestimating the changes. This is most relevant to alar width, alar base width, and tip projection measurements. The authors believe measurements obtained for nasolabial angles and columellar inclination were accurately represented by the photogrammetric measurements. The assessment of patients’ objective satisfaction was not conducted anonymously, which we would improve in future studies. While an algorithmic approach would be helpful in evaluating patients with paranasal deficiencies, the authors were unable to create (let alone validate) any algorithm or classification system, due to small case numbers. In future studies, more cases and sophisticated 3D analyses wound undoubtedly enhance the meaning of the results. This study is the first of its kind to include a control group to account for soft tissue response after paranasal augmentation. The results therefore shed light on the influence of skeletal augmentation alone on the soft tissue envelope. CONCLUSIONS Paranasal augmentation using PPE or autologous material will predictably alter paranasal measurements with minimal morbidity. Surgeons can anticipate an increase in alar width, alar base width with paranasal augmentation, and modify the surgical plan on an individual basis. Supplementary Material This article contains supplementary material located online at www.aestheticsurgeryjournal.com. Disclosures The authors declared no potential conflicts of interest with respect to the research, authorship, and publication of this article. Funding The authors received no financial support for the research, authorship, and publication of this article. REFERENCES 1. Yaremchuk MJ, Israeli D. Paranasal implants for correction of midface concavity. Plast Reconstr Surg . 1998; 102( 5): 1676- 1684; discussion 1685. Google Scholar CrossRef Search ADS PubMed  2. Park JH, Kim JW, Kim SJ. Midfacial Soft-Tissue Changes after Paranasal Augmentation with Porous Polyethylene. Facial Plast Surg . 2016; 32( 2): 232- 237. Google Scholar CrossRef Search ADS PubMed  3. Park SB, Kim YI, Hwang DS, Lee JY. Midfacial soft-tissue changes after mandibular setback surgery with or without paranasal augmentation: cone-beam computed tomography (CBCT) volume superimposition. J Craniomaxillofac Surg . 2013; 41( 2): 119- 123. Google Scholar CrossRef Search ADS PubMed  4. Han K, Kwon HJ, Choi TH, Kim JH, Son D. Comparison of anthropometry with photogrammetry based on a standardized clinical photographic technique using a cephalostat and chair. J Craniomaxillofac Surg . 2010; 38( 2): 96- 107. Google Scholar CrossRef Search ADS PubMed  5. Zelken JA, Hong JP, Broyles JM, Hsiao YC. Preventing Elevated Radix Deformity in Asian Rhinoplasty with a Chimeric Dorsal-Glabellar Construct. Aesthet Surg J . 2016; 36( 3): 287- 296. Google Scholar CrossRef Search ADS PubMed  6. Kwon TG, Kang SM, Hwang HD. Three-dimensional soft tissue change after paranasal augmentation with porous polyethylene. Int J Oral Maxillofac Surg . 2014; 43( 7): 816- 823. Google Scholar CrossRef Search ADS PubMed  7. Yaremchuk MJ, Vibhakar D. Pyriform Aperture Augmentation as An Adjunct to Rhinoplasty. Clin Plast Surg . 2016; 43( 1): 187- 193. Google Scholar CrossRef Search ADS PubMed  8. Yaremchuk MJ, Doumit G, Doumit G, Thomas MA. Alloplastic augmentation of the facial skeleton: an occasional adjunct or alternative to orthognathic surgery. Plast Reconstr Surg . 2011; 127( 5): 2021- 2030. Google Scholar CrossRef Search ADS PubMed  9. Rahpeyma A, Khajehahmadi S. The Need for Lateral Piriform Rim Augmentation in Patients with Unilateral Cleft Lip/Palate During Alveolar Cleft Bone Grafting. J Maxillofac Oral Surg . 2015; 14( 3): 573- 577. Google Scholar CrossRef Search ADS PubMed  10. Park H, Chun KW, Kye MS, Dhong ES, Yoon ES. Midface augmentation using bony segments obtained from sagittal splitting angle ostectomy in asians. Plast Reconstr Surg . 2008; 121( 2): 578- 586. Google Scholar CrossRef Search ADS PubMed  11. Atherton D, Haers P. Midfacial augmentation in teenage cleft patients using malar and paranasal Medpor implants. Int J Oral Maxillofac Surg . 2014; 43( 7): 824- 826. Google Scholar CrossRef Search ADS PubMed  12. Rai A, Datarkar A, Arora A, Adwani DG. Utility of high density porous polyethylene implants in maxillofacial surgery. J Maxillofac Oral Surg . 2014; 13( 1): 42- 46. Google Scholar CrossRef Search ADS PubMed  13. Yaremchuk MJ. Facial skeletal reconstruction using porous polyethylene implants. Plast Reconstr Surg . 2003; 111( 6): 1818- 1827. Google Scholar CrossRef Search ADS PubMed  14. Cenzi R, Farina A, Zuccarino L, Carinci F. Clinical outcome of 285 Medpor grafts used for craniofacial reconstruction. J Craniofac Surg . 2005; 16( 4): 526- 530. Google Scholar CrossRef Search ADS PubMed  15. Menderes A, Baytekin C, Topcu A, Yilmaz M, Barutcu A. Craniofacial reconstruction with high-density porous polyethylene implants. J Craniofac Surg . 2004; 15( 5): 719- 724. Google Scholar CrossRef Search ADS PubMed  16. Muradin MS, Seubring K, Stoelinga PJ, vd Bilt A, Koole R, Rosenberg AJ. A prospective study on the effect of modified alar cinch sutures and V-Y closure versus simple closing sutures on nasolabial changes after Le Fort I intrusion and advancement osteotomies. J Oral Maxillofac Surg . 2011; 69( 3): 870- 876. Google Scholar CrossRef Search ADS PubMed  17. Park SB, Yoon JK, Kim YI, Hwang DS, Cho BH, Son WS. The evaluation of the nasal morphologic changes after bimaxillary surgery in skeletal class III maloccusion by using the superimposition of cone-beam computed tomography (CBCT) volumes. J Craniomaxillofac Surg . 2012; 40( 4): e87- e92. Google Scholar CrossRef Search ADS PubMed  18. Liu X, Zhu S, Hu J. Modified versus classic alar base sutures after LeFort I osteotomy: a systematic review. Oral Surg Oral Med Oral Pathol Oral Radiol . 2014; 117( 1): 37- 44. Google Scholar CrossRef Search ADS PubMed  19. Jung YJ, Kim MJ, Baek SH. Hard and soft tissue changes after correction of mandibular prognathism and facial asymmetry by mandibular setback surgery: three-dimensional analysis using computerized tomography. Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2009; 107( 6): 763- 771.e8. Google Scholar CrossRef Search ADS PubMed  20. Metzler P, Geiger EJ, Chang CC, Sirisoontorn I, Steinbacher DM. Assessment of three-dimensional nasolabial response to Le Fort I advancement. J Plast Reconstr Aesthet Surg . 2014; 67( 6): 756- 763. Google Scholar CrossRef Search ADS PubMed  21. Kim M, Lee DY, Lim YK, Baek SH. Three-dimensional evaluation of soft tissue changes after mandibular setback surgery in class III malocclusion patients according to extent of mandibular setback, vertical skeletal pattern, and genioplasty. Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2010; 109( 5): e20- e32. Google Scholar CrossRef Search ADS PubMed  © 2018 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Aesthetic Surgery Journal Oxford University Press

The Influence of Paranasal Augmentation on the Measurement of the Nose for the Treatment of Midfacial Concavity

Loading next page...
 
/lp/ou_press/the-influence-of-paranasal-augmentation-on-the-measurement-of-the-nose-0sxdnCVSaT
Publisher
Mosby Inc.
Copyright
© 2018 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com
ISSN
1090-820X
eISSN
1527-330X
D.O.I.
10.1093/asj/sjx166
Publisher site
See Article on Publisher Site

Abstract

Abstract Background A concave midface with its associated deep nasolabial folds is more aesthetically displeasing than a convex midface. Midfacial concavity may be addressed with autologous tissue and implants. Objectives The aim of this study was to determine the effect of paranasal augmentation on photogrammetric parameters. Methods Between July 2013 and August 2016, 12 patients underwent paranasal augmentation to address midface concavity. Augmentation was performed with autologous rib cartilage, autologous mandibular bone, or preshaped porous polyethylene (PPE). All operations were performed through the upper gingivobuccal approach. Twelve patients who underwent malar reduction using the same approach acted as a control group to account for the influence of the approach on soft tissue change. Preoperative and postoperative measurements were made photogrammetrically. Results The average follow-up period was 12.8 months (range, 5-30 months) for both groups. The mean thickness of augmentation grafts was 5.18 mm (range, 3-7 mm). Alar width and alar base width increased 4.84% (P = 0.01) and 7.66% (P = 0.01), respectively. The nasolabial angle increased from 97.2°to 103.6° and the columellar inclination increased from 116.0° to 119.1° but neither were statistically significant. Photogrammetric parameters did not change significantly in the control group. Partial wound dehiscence occurred in one case. There was greater postoperative increase in alar width (P = 0.020), alar base width (P = 0.024), and nasolabial angle (P = 0.033) in the experimental group compared to the control group. Conclusions Paranasal augmentation using PPE or autologous material generates measurable soft tissue changes designed to enhance paranasal aesthetics. Level of Evidence: 3 Midface concavity may be aesthetically displeasing and accelerate the appearance of facial aging.1,2 Patients with paranasal volume deficiency and localized concavity present with a flattened facial profile, compressed nasolabial angle, and deepening of furrows around the nose and mouth.2,3 Improvement of paranasal deficiency can be achieved by malar osteotomy, Le Fort I osteotomy, or both.3 When there is paranasal deficiency and a normally positioned maxilla,2 augmentation of the depressed area can camouflage the paranasal deficiency. This is accomplished with autogenous bone graft or alloplastic materials.2 The influence of paranasal augmentation on the surrounding soft tissue envelope remains unclear. Factors like incision placement, plane of dissection, wound closure technique, and scar formation are expected to influence the aesthetic outcome. The aim of this study was to determine the effect of paranasal augmentation on photogrammetric measurements. By comparing these changes with a control group, we controlled for the impact of the surgical approach on the outcome. To our knowledge, this is the first series about paranasal augmentation that compares an experimental group and a control group. METHODS This retrospective study was performed at Chang Gung Memorial Hospital after obtaining approval from the Institutional Review Board. Between July 2013 and August 2016, twenty-one patients with midface convexity and paranasal volume deficiency underwent paranasal augmentation for correction of midface concavity. Patients were included if they presented with acceptable occlusion and did not warrant orthognathic surgery, and did not have fat graft or filler injection. Informed consent was obtained for all patients. Nine patients who underwent simultaneous rhinoplasty were excluded. In the twelve remaining patients, paranasal augmentation was achieved using autologous rib cartilage (n = 1), autologous bone from the mandibular angle (n = 1), and preshaped porous polyethylene (PPE, Medpor, Stryker, Kalamazoo, MI, n = 10). All operations were performed under general anesthesia. Bilateral upper gingivobuccal sulcus incisions were used, lateral to the pyriform aperture, above the root of the central incisor to the canine eminence and 1 cm above the sulcus to provide an adequate cuff of mucosa for wound closure.4 The incisions did not connect at the midline and subperiosteal dissection was conservative. Autogenous and alloplastic grafts were contoured to adapt to the depressed recipient site5 and trimmed along the margin of the canine root to avoid iatrogenic injury during fixation. The graft edges were contoured to the recipient bone for a more natural contour. PPE was soaked in an antibiotic solution with negative pressure.2 Using a syringe, an air-tight seal was created with a gloved finger, and the plunger was withdrawn to create a near vacuum.2 After the shape and position of the autogenous graft or PPE was confirmed, grafts and implants were secured with an 8-mm or 10-mm miniscrew centrally. Special attention was taken to avoid injury to the tooth root (Figure 1). A 3-0 nylon alar cinch suture was placed between transverse nasalis muscles at the alar-facial junction and the overlying mucosa was closed with absorbable sutures. Drains were not placed. The surgical procedure is demonstrated in the video (available online as Supplementary Material at www.aestheticsurgeryjournal.com). Figure 1. View largeDownload slide A 36-year-old woman with intraoperative view of paranasal PPE implants fixed with miniscrews. Figure 1. View largeDownload slide A 36-year-old woman with intraoperative view of paranasal PPE implants fixed with miniscrews. Video 1 Watch now at https://academic.oup.com/asj/article-lookup/doi/10.1093/asj/sjx166 Video 1 Watch now at https://academic.oup.com/asj/article-lookup/doi/10.1093/asj/sjx166 Close Twelve consecutive patients who underwent malar reduction through the same approach, using an alar cinch suture and identical wound closure technique, acted as a control group. This was intended to control for the effect of the gingivobuccal incision, subperiosteal dissection plane, and wound closure technique on soft tissue change. We used standardized photogrammetric methodology and efforts were made to ensure true profile views were obtained by the use of paper tape at 0°, 45°, 90°, 135°, and 180°, with the camera lens at 90° from a rotating stool. Patients were asked to look straight ahead with eyes in neutral position.5 In both groups, alar width, alar base width, tip projection, nasolabial angle, and columellar inclination were measured pre- and postoperatively with previously described photogrammetric methodology using the Adobe Photoshop CS6 measure tool (Adobe Systems, Inc., San Jose, CA).4,5 All measurements were performed by the same investigator (C.I.Y.). The definitions of the parameters are given in Table 1 and Figure 2. The augmentation and control group were compared. Table 1. Definitions of Linear and Angular Parameters Parameter   Definition   Alar width  Distance between the most lateral part of bilateral alar wings  Alar base width  Distance between bilateral alar base  Tip projection  Distance between tip to coronal plane  Nasolabial angle  Angle of columellar-subnasale-labrale superius  Columellar inclination  Angle of coronal plane to columellar-subnasale  Coronal plane  The plane perpendicular to Frankfort horizontal plane and passed the most-protruding part of pupil  Parameter   Definition   Alar width  Distance between the most lateral part of bilateral alar wings  Alar base width  Distance between bilateral alar base  Tip projection  Distance between tip to coronal plane  Nasolabial angle  Angle of columellar-subnasale-labrale superius  Columellar inclination  Angle of coronal plane to columellar-subnasale  Coronal plane  The plane perpendicular to Frankfort horizontal plane and passed the most-protruding part of pupil  View Large Figure 2. View largeDownload slide A 36-year-old woman with (A) Linear measurement in this study: alar width, alar base width. (B) tip projection (A-B distance). Angular measurements in this study: nasolabial angle (angle of C-D-E, collumellar-subnasale-labrale superius), columellar inclination (angle of C-D (columellar-subnasale) to coronal plane). Figure 2. View largeDownload slide A 36-year-old woman with (A) Linear measurement in this study: alar width, alar base width. (B) tip projection (A-B distance). Angular measurements in this study: nasolabial angle (angle of C-D-E, collumellar-subnasale-labrale superius), columellar inclination (angle of C-D (columellar-subnasale) to coronal plane). For subjective outcome assessment, we utilized a simple questionnaire (Appendix A, available online as Supplementary Material at www.aestheticsurgeryjournal.com). composed of three questions that measured the degree of satisfaction of the aesthetic outcome and soft tissue change. We performed the questionnaire by telephone interview by the same investigator (a research assistant). For each question, the patient assigned a score from 1 to 5, where higher scores indicated greater satisfaction. Average scores for each question were calculated. Statistical Analysis Statistical analyses were performed using SPSS package version 20.0 for Windows. Statistical differences were evaluated by the analysis of variance test with Mann-Whiney test and paired ttest. P values of less than 0.05 were considered statistically significant. RESULTS Table 2 summarizes the demographics of the paranasal augmentation group. There were 2 men and 10 women with a mean age of 32.5 years (range, 18-50 years). In the control group, there were 2 men and 10 women with a mean age of 32.8 years (range, 25-48 years). There was no significant change with all the parameters (P > 0.05) after upper gingivobuccal incision for malar reduction. Table 2. Demographics and Characteristics of Augmentation Group No.  Sex  Age (years)  Material  Thickness (mm)  Follow up (months)  Complication  1  F  37  Medpor  6  6  —  2  M  28  Medpor  7  16  —  3  F  18  Medpor  4.5  17  —  4  F  36  Medpor  3  10  —  5  F  50  Medpor  6  13  —  6  F  23  Medpor  4.5  5  Wound dehiscence  7  F  39  Medpor  7  6  —  8  M  31  Medpor  4.5  8  —  9  F  32  Rib  5  27  —  10  F  30  Medpor  4.5  7  —  11  F  32  Mandible angle  4  30  —  12  F  33  Medpor  6  8  —  No.  Sex  Age (years)  Material  Thickness (mm)  Follow up (months)  Complication  1  F  37  Medpor  6  6  —  2  M  28  Medpor  7  16  —  3  F  18  Medpor  4.5  17  —  4  F  36  Medpor  3  10  —  5  F  50  Medpor  6  13  —  6  F  23  Medpor  4.5  5  Wound dehiscence  7  F  39  Medpor  7  6  —  8  M  31  Medpor  4.5  8  —  9  F  32  Rib  5  27  —  10  F  30  Medpor  4.5  7  —  11  F  32  Mandible angle  4  30  —  12  F  33  Medpor  6  8  —  View Large The average thickness of Medpor, rib, and bone used for augmentation was 5.18 mm (range, 3 mm to 7 mm). The alar width and alar base width increased 4.84% (P = 0.010) and 7.66% (P = 0.010) postoperatively. Tip projection increased 7.77% (P = 0.462) after paranasal augmentation. The nasolabial angle increased from 97.2° to 103.6°. The average increase was 6.4° (range, 1°-20°) but the change was not significant (P = 0.068). Columellar inclination increased from 116.0° to 119.1°. The average increase was 3.08° (range, 2°-17°) but the difference was not significant. The postoperative increase in alar width (P = 0.020), alar base width (P = 0.024), and nasolabial angle (P = 0.033) was greater in the augmentation group compared to the control group (Table 3). Table 3. Measurements of Midface Soft Tissue Change Between Augmentation Group and Control Group (statistically significant at *P < 0.05, data presented as mean ± standard deviation)   Control group, N = 12   Augmentation group, N = 12   P value   Preoperative  Postoperative  P value  Preoperative  Postoperative  P value  Age (years)  32.45 ± 8.5  —  —  32.83 ± 7.2  —  —  0.644  Alar width  172.2 ± 39.0  173.64 ± 39.7  0.218  209.6 ± 41.0  216.8 ± 42.7  0.010*  0.020 *  Alar base width  111.6 ± 21.2  112.5 ± 21.3  0.054  116.3 ± 34.3  126.1 ± 36.7  0.010 *  0.024 *  Tip projection  55.2 ± 13.6  54.6 ± 13.0  0.543  109.0 ± 46.4  113.8 ± 36.3  0.462  0.309  Nasolabial angle (°)  98.6 ± 10.4  97.3 ± 8.5  0.788  97.2 ± 16.0  103.6 ± 15.3  0.068  0.033 *  Columellar inclination (°)  110.2 ± 6.9  108.5 ± 8.4  0.834  116.0 ± 16.1  119.1 ± 13.8  0.243  0.156    Control group, N = 12   Augmentation group, N = 12   P value   Preoperative  Postoperative  P value  Preoperative  Postoperative  P value  Age (years)  32.45 ± 8.5  —  —  32.83 ± 7.2  —  —  0.644  Alar width  172.2 ± 39.0  173.64 ± 39.7  0.218  209.6 ± 41.0  216.8 ± 42.7  0.010*  0.020 *  Alar base width  111.6 ± 21.2  112.5 ± 21.3  0.054  116.3 ± 34.3  126.1 ± 36.7  0.010 *  0.024 *  Tip projection  55.2 ± 13.6  54.6 ± 13.0  0.543  109.0 ± 46.4  113.8 ± 36.3  0.462  0.309  Nasolabial angle (°)  98.6 ± 10.4  97.3 ± 8.5  0.788  97.2 ± 16.0  103.6 ± 15.3  0.068  0.033 *  Columellar inclination (°)  110.2 ± 6.9  108.5 ± 8.4  0.834  116.0 ± 16.1  119.1 ± 13.8  0.243  0.156  View Large There were no complications including hematoma, infection, implant extrusion, or implant migration during the follow-up period of 12.8 months (range, 5 months to 30 months). Only one patient had partial intraoral wound dehiscence and recovered after aggressive oral hygiene and limited debridement with wound repair two weeks later. During the follow-up period, no patient complained about foreign body sensations over the paranasal region, nasal floor, lateral nasal linings, or gingival area. Nor did any patient suffer from airway obstruction. There were no visible or palpable stepoffs. All patients were all satisfied with the aesthetic outcome and improved soft tissue change in paranasal and nasal area, with average satisfaction scores of 4.5 (range, 4-5), 4.6 (range, 4-5), and 4.5 (range, 3-5) out of 5, respectively. Figures 3 and 4 compare these changes in the control group and augmentation group. Figure 3. View large Download slide View large Download slide A 38-year-old woman in the control group with (A, C, E, G, I, K) preoperative and (B, D, F, H, J, L) 12-month postoperative outcomes. Figure 3. View large Download slide View large Download slide A 38-year-old woman in the control group with (A, C, E, G, I, K) preoperative and (B, D, F, H, J, L) 12-month postoperative outcomes. Figure 4. View large Download slide View large Download slide A 30-year-old woman in the augmentation group with (A, C, E, G, I, K) preoperative and (B, D, F, H, J, L) 12-month postoperative outcome. Figure 4. View large Download slide View large Download slide A 30-year-old woman in the augmentation group with (A, C, E, G, I, K) preoperative and (B, D, F, H, J, L) 12-month postoperative outcome. DISCUSSION Paranasal augmentation is useful for correcting midfacial concavity without malocclusion.1,6,7 It can simulate the visual effects of skeletal osteotomies without affecting dental occlusion.1,8 It is an often useful adjunct to rhinoplasty, and can improve the soft tissue relationship between the perinasal and upper lip areas.7 Various methods are described for correction of paranasal volume deficiency.3 Autogenous bone graft is a dependable option for augmentation,9,10 but donor site morbidity must be considered, and the resorption of graft could generate unpredictable results.2,3 A sound understanding of the 3-dimensional (3D) anatomy and finesse is requisite for sculpting of the graft; this should be considered in less experienced hands.3 Alloplastic materials including porous polyethylene have resultantly gained widespread acceptance.2,6 PPE is strong, biocompatible, and allows for tissue ingrowth with resistance to infection. It is available in prefabricated shapes and sizes, is easy to shape, will not resorb, and there is no donor site morbidity.2,3,6,11,12 PPE implants have many craniofacial reconstructive applications12-15 and are associated with satisfactory outcomes. There is a deficiency of literature that quantifies the effect of paranasal augmentation on the soft tissue envelope. The studies that exist have used cone-beam computed tomography and lateral cephalograms to objectively measure soft tissue changes.2,3,6 The relationship between the thickness of paranasal implant and soft tissue change has been studied;2,6 the average increase in soft tissue outline in the peri-alar region is 68% to 80.7% of implant thickness.2,6 The focus of this study was not projection of the implant. Instead, the authors evaluated the photogrammetric changes of the paranasal region after augmentation. In this study, photogrammetry demonstrated that there is significant increase in alar width and alar base width and a trend toward nasolabial angle widening after augmentation. The effect was most profound along the upper lip subunit. Correction of midface hypoplasia was achieved by adding paranasal fullness, effacing prominent nasolabial grooves, and blunting the nasolabial angle. These changes are thought to contribute to a more youthful appearance and more attractive facial profile. The results from this series corroborated those from a similar study by Kwon et al.6 In that study, however, there was significant increase of columellar inclination whereas our results demonstrated no significant change. It is possible that variations in measurement methods or case numbers contributed to this distinction. The biggest difference between this series and other series in the literature is the study design. The authors compared soft tissue change in a paranasal augmentation group and a control group using the same incision, plane of dissection, and closure technique. This was designed to control for the possibility that disruption of the paranasal periosteum would influence the muscles near the alar base.6 Widening of the alar base is a known adverse outcome after Le Fort I advancement, even when V-Y closure is performed or alar base cinch suture is placed.6,16-19 Furthermore, it is reported that there is no significant correlation between soft tissue changes and maxillary advancement.20 Kim et al suggested that paranasal soft tissue changes could result from muscle and soft tissue tension.3,20,21 Clearly, there is no consensus on whether a vestibular incision with or without cinch suture influences the shape of the nose and paranasal soft tissue envelope. The effect of the surgical approach and wound closure on the soft tissue envelope warrants further study.2,3,6 To our knowledge, this study is the first to control for these changes, and to objectively quantify them in a control group. Indeed, the authors found that there is no significant change in alar width, alar base width, tip projection, nasolabial angle, and columellar inclination in the control group. Controlling for potential confounders allowed the authors to attribute changes in alar width, alar base width and nasolabial angle to paranasal augmentation alone. In patients with a normal profile, postsurgical alar and alar base widening are considered adverse outcomes. However, in patients with paranasal volume deficiency and midface concavity, said changes may contribute to a more youthful and attractive appearance.8 Changes in the upper lip and nose improves overall facial balance. In patients with midfacial concavity and excessive alar width, these relationships must be taken into consideration. In some cases, it may even be necessary to augment the paranasal region in addition to alar reduction. Alternatively, patients with preexisting alar narrowing such as overreduction of alar base, may benefit from additional alar widening. For these reasons, every patient must be evaluated individually. Thoughtful preoperative evaluation, guidance, and treatment planning is paramount to successful augmentation. The PPE implants used in this study are preshaped. They are crescentic and available in two sizes: 27 mm × 25 mm × 4.5 mm of projection, and 30 mm × 28 mm × 7 mm of projection.1,7 For unilateral cases, the contralateral side is used a reference to determine the thickness of augmentation grafts and tailored intraoperatively for symmetry. When there is bilateral concavity, the thickness is determined by the severity of concavity. The goal is to achieve a balance between midface volume correction, alar widening, and improved facial profile harmony. In the future, 3D simulation may guide surgical decision making to achieve more predictable outcomes. The soft tissue envelope and facial skeleton contribute to midface contour and convexity.8 Thus, soft tissue and skeletal augmentation may correct midfacial deficiency, but the influence of each component may vary from patient to patient. For example, fat grafting and injection of fillers may address soft tissue volume loss associated with aging where there is no need to augment skeletal projection.8 In such a patient, augmentation of the facial skeleton may project the midface, but augmentation of the soft tissue envelope will more effectively blunt the contours of the skeleton.6 When analyzing the face, clinicians should consider bony and soft tissue deficiencies independently.3 The patients presented in this series were young, and their paranasal volume deficiencies resulted more from skeletal deficiency than changes associated with aging. Midfacial concavity resulting from maxillary hypoplasia is more common in certain ethnic groups, including Asians and Blacks.1 The PPE is a dependable substitute for bone and cartilage in facial skeletal augmentation. Paranasal augmentation with PPE is straightforward and the result is long-lasting. In other series, the complication rate of PPE augmentation was 0.9% to 17.5%.6,11 In our series, the long-term complication rate was 0 and there were no explanted implants. One patient had partial wound dehiscence but recovered with aggressive oral hygiene and limited debridement and repair. There were no other early or late complications and all patients were satisfied with the aesthetic outcome. A major limitation of this study is the small sample size. In this series, it was difficult to determine a precise soft tissue response because the severity of volume deficiency varied, and the thickness of PPE and autograft were not standardized.6 The materials used were also not uniform, and resorption of grafts was not studied. Both patients with autologous grafts had the longest follow up in this series (30 months and 27 months), but the absorption rate warrants further evaluation in future studies. There were also limitations in the photogrammetric methodology. Conversion of a 3D object into two dimensions may limit the validity of the increases reported in this series by underestimating the changes. This is most relevant to alar width, alar base width, and tip projection measurements. The authors believe measurements obtained for nasolabial angles and columellar inclination were accurately represented by the photogrammetric measurements. The assessment of patients’ objective satisfaction was not conducted anonymously, which we would improve in future studies. While an algorithmic approach would be helpful in evaluating patients with paranasal deficiencies, the authors were unable to create (let alone validate) any algorithm or classification system, due to small case numbers. In future studies, more cases and sophisticated 3D analyses wound undoubtedly enhance the meaning of the results. This study is the first of its kind to include a control group to account for soft tissue response after paranasal augmentation. The results therefore shed light on the influence of skeletal augmentation alone on the soft tissue envelope. CONCLUSIONS Paranasal augmentation using PPE or autologous material will predictably alter paranasal measurements with minimal morbidity. Surgeons can anticipate an increase in alar width, alar base width with paranasal augmentation, and modify the surgical plan on an individual basis. Supplementary Material This article contains supplementary material located online at www.aestheticsurgeryjournal.com. Disclosures The authors declared no potential conflicts of interest with respect to the research, authorship, and publication of this article. Funding The authors received no financial support for the research, authorship, and publication of this article. REFERENCES 1. Yaremchuk MJ, Israeli D. Paranasal implants for correction of midface concavity. Plast Reconstr Surg . 1998; 102( 5): 1676- 1684; discussion 1685. Google Scholar CrossRef Search ADS PubMed  2. Park JH, Kim JW, Kim SJ. Midfacial Soft-Tissue Changes after Paranasal Augmentation with Porous Polyethylene. Facial Plast Surg . 2016; 32( 2): 232- 237. Google Scholar CrossRef Search ADS PubMed  3. Park SB, Kim YI, Hwang DS, Lee JY. Midfacial soft-tissue changes after mandibular setback surgery with or without paranasal augmentation: cone-beam computed tomography (CBCT) volume superimposition. J Craniomaxillofac Surg . 2013; 41( 2): 119- 123. Google Scholar CrossRef Search ADS PubMed  4. Han K, Kwon HJ, Choi TH, Kim JH, Son D. Comparison of anthropometry with photogrammetry based on a standardized clinical photographic technique using a cephalostat and chair. J Craniomaxillofac Surg . 2010; 38( 2): 96- 107. Google Scholar CrossRef Search ADS PubMed  5. Zelken JA, Hong JP, Broyles JM, Hsiao YC. Preventing Elevated Radix Deformity in Asian Rhinoplasty with a Chimeric Dorsal-Glabellar Construct. Aesthet Surg J . 2016; 36( 3): 287- 296. Google Scholar CrossRef Search ADS PubMed  6. Kwon TG, Kang SM, Hwang HD. Three-dimensional soft tissue change after paranasal augmentation with porous polyethylene. Int J Oral Maxillofac Surg . 2014; 43( 7): 816- 823. Google Scholar CrossRef Search ADS PubMed  7. Yaremchuk MJ, Vibhakar D. Pyriform Aperture Augmentation as An Adjunct to Rhinoplasty. Clin Plast Surg . 2016; 43( 1): 187- 193. Google Scholar CrossRef Search ADS PubMed  8. Yaremchuk MJ, Doumit G, Doumit G, Thomas MA. Alloplastic augmentation of the facial skeleton: an occasional adjunct or alternative to orthognathic surgery. Plast Reconstr Surg . 2011; 127( 5): 2021- 2030. Google Scholar CrossRef Search ADS PubMed  9. Rahpeyma A, Khajehahmadi S. The Need for Lateral Piriform Rim Augmentation in Patients with Unilateral Cleft Lip/Palate During Alveolar Cleft Bone Grafting. J Maxillofac Oral Surg . 2015; 14( 3): 573- 577. Google Scholar CrossRef Search ADS PubMed  10. Park H, Chun KW, Kye MS, Dhong ES, Yoon ES. Midface augmentation using bony segments obtained from sagittal splitting angle ostectomy in asians. Plast Reconstr Surg . 2008; 121( 2): 578- 586. Google Scholar CrossRef Search ADS PubMed  11. Atherton D, Haers P. Midfacial augmentation in teenage cleft patients using malar and paranasal Medpor implants. Int J Oral Maxillofac Surg . 2014; 43( 7): 824- 826. Google Scholar CrossRef Search ADS PubMed  12. Rai A, Datarkar A, Arora A, Adwani DG. Utility of high density porous polyethylene implants in maxillofacial surgery. J Maxillofac Oral Surg . 2014; 13( 1): 42- 46. Google Scholar CrossRef Search ADS PubMed  13. Yaremchuk MJ. Facial skeletal reconstruction using porous polyethylene implants. Plast Reconstr Surg . 2003; 111( 6): 1818- 1827. Google Scholar CrossRef Search ADS PubMed  14. Cenzi R, Farina A, Zuccarino L, Carinci F. Clinical outcome of 285 Medpor grafts used for craniofacial reconstruction. J Craniofac Surg . 2005; 16( 4): 526- 530. Google Scholar CrossRef Search ADS PubMed  15. Menderes A, Baytekin C, Topcu A, Yilmaz M, Barutcu A. Craniofacial reconstruction with high-density porous polyethylene implants. J Craniofac Surg . 2004; 15( 5): 719- 724. Google Scholar CrossRef Search ADS PubMed  16. Muradin MS, Seubring K, Stoelinga PJ, vd Bilt A, Koole R, Rosenberg AJ. A prospective study on the effect of modified alar cinch sutures and V-Y closure versus simple closing sutures on nasolabial changes after Le Fort I intrusion and advancement osteotomies. J Oral Maxillofac Surg . 2011; 69( 3): 870- 876. Google Scholar CrossRef Search ADS PubMed  17. Park SB, Yoon JK, Kim YI, Hwang DS, Cho BH, Son WS. The evaluation of the nasal morphologic changes after bimaxillary surgery in skeletal class III maloccusion by using the superimposition of cone-beam computed tomography (CBCT) volumes. J Craniomaxillofac Surg . 2012; 40( 4): e87- e92. Google Scholar CrossRef Search ADS PubMed  18. Liu X, Zhu S, Hu J. Modified versus classic alar base sutures after LeFort I osteotomy: a systematic review. Oral Surg Oral Med Oral Pathol Oral Radiol . 2014; 117( 1): 37- 44. Google Scholar CrossRef Search ADS PubMed  19. Jung YJ, Kim MJ, Baek SH. Hard and soft tissue changes after correction of mandibular prognathism and facial asymmetry by mandibular setback surgery: three-dimensional analysis using computerized tomography. Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2009; 107( 6): 763- 771.e8. Google Scholar CrossRef Search ADS PubMed  20. Metzler P, Geiger EJ, Chang CC, Sirisoontorn I, Steinbacher DM. Assessment of three-dimensional nasolabial response to Le Fort I advancement. J Plast Reconstr Aesthet Surg . 2014; 67( 6): 756- 763. Google Scholar CrossRef Search ADS PubMed  21. Kim M, Lee DY, Lim YK, Baek SH. Three-dimensional evaluation of soft tissue changes after mandibular setback surgery in class III malocclusion patients according to extent of mandibular setback, vertical skeletal pattern, and genioplasty. Oral Surg Oral Med Oral Pathol Oral Radiol Endod . 2010; 109( 5): e20- e32. Google Scholar CrossRef Search ADS PubMed  © 2018 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com

Journal

Aesthetic Surgery JournalOxford University Press

Published: Mar 1, 2018

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off