Morphological Changes of the Mandibular Angle After Orthognathic Surgery with Class III Deformity in East Asia.

The aims of this study were to analyze the morphological changes of the mandibular angle after orthognathic surgery for mandibular setback and investigate related factors. This retrospective study included patients from January 2017 to December 2021 diagnosed with skeletal class III deformity who underwent BSSRO (Group I) or bimaxillary surgery (Group II). Preoperative (T0), within 1 month postoperatively (T1), and 6 months postoperatively (T2) CT scans were collected from 61 patients to three-dimensionally analyze the proximal segment displacement, the linear and angular changes of the mandibular angle. The gonion points moved posteriorly and laterally (P < 0.001), while the inferior movement was not significant (P = 1.000, P = 0.274). The intergonial width increased by 3.32 ± 1.87 mm and 2.34 ± 1.77 mm as revealed by T2 CTs, respectively, in Group I and Group II. Mandibular angle decreased in both groups and by 1.41 ± 2.95° in Group I and 1.37 ± 3.41° in Group II. The increase in intergonial width between T1 and T0 was negatively correlated with the preoperative mandibular angle (P = 0.003) and positively correlated with the transverse outward movement of the proximal segment (P < 0.001). After surgery, the intergonial width increased and the inferior and posterior border of the proximal segment flared outward. The changes in intergonial width and mandibular angle were mainly related to the rotation of the proximal segment, which has a certain impact on the aesthetics of the lower face. Therefore, controlling the position of the proximal segment is of vital importance to lessen the changes in the mandibular angle area.Level of Evidence III. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Evaluation of Different Fixation Methods Combinations After L-Shaped Osteotomy Reduction Malarplasty: An In Vitro Biomechanical Study.

BACKGROUND: This in vitro study compared the stability of different fixation method combinations for the zygomatic complex after simulated L-shaped osteotomy reduction malarplasty, a common facial contouring surgery in East Asia with high postoperative complications due to poor fixation methods. MATERIALS AND METHODS: The study used 108 zygoma replicas with various fixation methods combinations in the zygomatic body (L-shaped plate with short wing on zygoma and on the maxilla, two bicortical screws, one bicortical screw with L-shaped plate, square plate, and rectangular plate) and zygomatic arch (Mortise-Tenon structure, 3-hole plate, and Mortise-Tenon structure plus short screw). The failure force under incremental load was applied through the Instron tensile machine to a well-stabilized model using a rubber band simulating the masseter muscle and recorded the increasing force digitally. ANOVA test was used for comparison between recorded values (P < 0.05). RESULTS: The results showed that the most stable combination was a six-hole rectangular plate and a Mortise-Tenon structure plus one short screw (358.55 ± 51.64 N/mm2). The results also indicated that the placement vector of the fixation methods around the L-shaped osteotomy and the use of the two-bridge fixation method were important factors in enhancing the stability of the zygomatic complex. CONCLUSION: The study suggested that surgeons should choose appropriate fixation methods based on these factors to reduce postoperative complications and improve surgical outcomes. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Stability of different fixation methods after reduction malarplasty under average and maximum masticatory forces: a finite element analysis.

BACKGROUND: Although titanium plates/screws are effective fixation methods (FM) after L-shaped osteotomy reduction malarplasty (LORM), the ideal FM remains controversial. This first finite element analysis (FEA) aimed to study the effect of various zygomatic body/zygomatic arch FM combinations and their placement vectors on the zygoma complex stability after virtual LORM under the effect of both average (150 N/mm2) and maximum (750 N/mm2) forces and three-dimensional (3D) mapping of stress and strain parameters distribution over the zygomatic bone, fixation methods, and total model. RESULTS: The fixation methods about the short-arm of the L-shaped osteotomy showed lower stress, strain, and displacement values than those across the long-arm osteotomy site. Combined with any zygomatic arch fixation methods (ZAFm), the two bicortical screws group (2LS) on the zygomatic body osteotomy site resulted in smaller displacements and the lowest zygoma bone stress and displacement when combined with Mortice-Tenon structure (MT) as zygomatic arch fixation method. Applied forces caused statistically significant differences in zygomatic bone stress (P < 0.001 and P = 0.001) and displacement (P = 0.001 and P = 0.002). CONCLUSION: All FMs both on the zygomatic body and zygomatic arch provide adequate zygomatic complex stability after LORM. The 2LS group showed better resistance than rectangular plate (RP) and square plate (SP) with lower stress concentrations. The L-shaped plate with short-wing on the maxilla (LPwM) is more stable than having the short-wing on the zygoma bone (LPwZ). Future prospective clinical studies are required to validate the current findings.

Two cleft palate simulators of Furlow double-opposing Z- palatoplasty: a comparative study.

PURPOSE: This study aimed to evaluate the efficiency of the porcine tongue for palatoplasty simulation compared to 3D-printed simulators and their surgical education role. MATERIALS AND METHODS: A total of 18 senior cleft surgeons participated in a palatoplasty simulation-based workshop conducted using porcine tongue simulators and 3D-printed simulators. This workshop consisted of a didactic session followed by a hands-on simulation session. Each participant independently used both simulators to perform Furlow double-opposing Z-plasty, which was assessed and scored by senior cleft surgeons using a scoring system including organizational flexibility and ductility, anatomical design simulation, proper incision, proper suturing, and convenience of operation. A paired t test was used for data statistical analysis and a P value < 0.05 was regarded as a statistically significant difference. RESULTS: All senior cleft surgeons strongly agreed that the simulation-based workshop was a valuable learning experience, and both simulators were useful and easy to manipulate (P = 1.00). The results of this comparative study showed that a porcine tongue palatoplasty simulator had an effectively significant difference in terms of organizational flexibility and ductility (P = 0.04), and suturing was better than the 3D-printed palatoplasty simulator (P < 0.01). There were no significant differences between the simulators regarding anatomical design simulation (P = 0.76) and incision simulation (P = 0.65). CONCLUSION: Both porcine tongue simulator and 3D-printed simulator have their unique strengths in surgical education for palatoplasty. Thus, the combined use of a porcine tongue and a 3D-printed cleft palate simulators are efficient as an educational model to practice Furlow double-opposing Z- palatoplasty. The porcine tongue simulators are superior in terms of organizational flexibility, ductility, and suturing simulators, while with the 3D-printed simulator, various palatoplasty techniques can be repeatedly practiced with better-simulated face and oral cavity.

Condylar positional changes and remodeling following bimaxillary anterior segment osteotomy with and without Le Fort I osteotomy: a three-dimensional comparative analysis.

OBJECTIVE: To evaluate 3D condylar displacement and long-term remodeling following the correction of bimaxillary protrusion by anterior segment osteotomy (ASO) with and without Le Fort I surgery. MATERIALS AND METHOD: This retrospective study included 32 adults with bimaxillary protrusion who underwent ASO alone (group 1) or with concomitant Le Fort I osteotomy (group 2). Subject's computed tomography scans at basic (T0), immediate postoperatively (T1), and at 1 year or more follow-up (T2) were collected. The condyle displacement was measured at superior-inferior, lateromedially, and anteroposterior surfaces, while condyle remodeling was measured at the superior, lateral, anterior, medial, and posterior surfaces. All 3D analyses were performed using 3D Slicer software (4.11.2). RESULTS: At T1, 52.7%, 86.7%, and 94.4% of condyles in group 1 were displaced inferiorly, laterally, and posteriorly, respectively, as well as 75%, 89.2%, and 53.5% of condyles in group 2, which had not fully returned to the original preoperative positions at T2. Condylar remodeling was observed in both groups at T2, and no significant difference was found in the overall condylar volume between T1 and T2 in both groups. Patients in group 2 exhibited significant bone resorption at both lateral and anterior surfaces compared to group 1 (P = 0.000 and 0.01, respectively). CONCLUSION: This study's results demonstrated that ASO is associated with a degree of condylar changes even if the posterior mandible is not osteomized. The positional changes vary between bimaxillary ASO alone and those with simultaneous Le Fort I osteotomy. However, both groups' condyle volume remained stable at the long-term follow-up.

Does adjunctive fixation in conjunction with miniplate affect condylar position and morphology after mandibular advancement through bilateral sagittal split ramus osteotomy? A retrospective 3-dimensional CT comparative study.

To minimize condylar positional and morphological changes after mandibular advancement through bilateral sagittal split ramus osteotomy (BSSRO), surgeons add either a bicortical screw or a two-hole plate distal to the conventional single miniplate. Since there have been no previous studies investigating the effect of this combination, our study aimed to evaluate the short- and long-term effects of these adjunctive fixation methods (AFM) on condylar positional and morphological changes after mandibular advancement through BSSRO. This retrospective cohort study included consecutive patients with retruded mandibles who were treated in the Department of Orthognathic and TMJ Surgery at West China Hospital of Stomatology, Sichuan University. The patients were divided into two groups based on the primary predictor variable, which was the addition of AFM - either a single bicortical screw or a two-hole plate in addition to the single miniplate. The primary outcome variable was the condylar positional and morphological changes after mandibular advancement through BSSRO. Three-dimensional facial CT scans were obtained at three different time points (preoperatively - T0, 1 week postoperatively - T1, and 1 year postoperatively - T2) and analyzed using ITK-SNAP, 3D Slicer, and SlicerSALT software. Intergroup comparisons were conducted with an independent t-test, with a p-value of <0.05 considered significant. Correlations between the variables were estimated by Pearson correlation. The study comprised 51 patients (32 females, 19 males; mean age 25.13 ± 4.24 years), involving a total of 81 condyles (21 unilateral and 60 bilateral). There was a significant difference in long-term condylar displacement in favor of AFM along with a single miniplate (p < 0.001). The bicortical screw group recorded less condylar displacement than the two-hole plate group horizontally (0.11 mm vs 0.22 mm) and sagittally (0.03 mm vs 0.17 mm), but more vertically (0.85 mm vs 0.03 mm). Bone formation associated with AFM occurred on all condylar surfaces, compared with only three surfaces in the single miniplate group. The adjunctive method in addition to the single miniplate fixation method showed less condylar displacement and more bone apposition after mandibular advancement through BSSRO. The follow-up duration variable was the only significant determinant for volumetric changes in the condyle.

Comparison of the biomechanical behavior between commercial and 3D-printed patient-specific Ti6Al4V L-Shaped titanium plates following le fort i osteotomy using finite element analysis: A technical Note.

OBJECTIVE: To evaluate and compare the biomechanical behavior of three-dimensionally (3D) printed patient-specific Ti6Al4V with commercially made titanium mini plates following Lefort-I osteotomy using finite element analysis. METHODS: Le Fort I osteotomy was virtually simulated with a 5 mm maxillary advancement and mediolateral rotation in the coronal plane, resulting in a 3 mm gap on the left side's posterior. Two fixation methods were modeled using software to compare 3D-printed Ti6Al4V and commercial titanium mini plates, both featuring a 4-hole l-shape with thicknesses of 0.5 mm and 0.7 mm at the strategic piriform rim and zygomaticomaxillary buttress locations. Using ANSYS R19.2, finite element models were developed to assess the fixation plates and maxilla's stress, strain, and displacement responses under occlusal forces of 125, 250, and 500 N/mm². RESULTS: This comparative analysis revealed slight variation in stress, strain, and displacement between the two models under varying loading conditions. Stress analysis indicated maximum stress concentrations at the vertical change in the left posterior area between maxillary segments, with the Ti6Al4V model exhibiting slightly higher stress values (187 MPa, 375 MPa, and 750 MPa) compared to the commercial titanium model (175 MPa, 351 MPa, and 702 MPa). Strain analysis showed that the commercial titanium model recorded higher strain values at the bending area of the l-shaped miniplate. Moreover, displacement analysis revealed a maximum of 3 mm in the left posterior maxilla, with the Ti6Al4V model demonstrating slightly lower displacement values under equivalent forces. CONCLUSION: The maximum stress, strain, and segment displacement of both fixation models were predominantly concentrated in the area of the gap between the maxillary segments. Notably, both fixation models exhibited remarkably close values, which can be attributed to the similar design of the fixation plates.

The effect of different hybrid rigid internal fixation techniques on the postoperative stability following a mandibular advancement using a bilateral sagittal split ramus osteotomy: A retrospective three-dimensional comparative study.

OBJECTIVE: To three-dimensionally evaluate post-operative mandibular stability following bilateral sagittal split ramus osteotomies between hybrid and non-hybrid rigid internal fixation techniques. MATERIALS AND METHOD: Seventy adults with skeletal class II deformity who underwent bilateral split sagittal osteotomy with mandibular advancement were included. Patients were divided into four groups based on their fixation techniques: hybrid technique (HT) groups I, II, and IV received a 4-hole 2 mm miniplate with either a bicortical screw (BS), additional 2 mm 4-hole miniplate, or two-hole miniplate, while non-HT group III received a 4-hole 2 mm miniplate with four mini-screws (MS). Measurements were taken pre-operatively (T0), immediately postoperatively (T1), and ≥1 year after surgery (T2) using 3D Slicer software. RESULTS: Age, sex, and follow-up period did not correlate significantly with postoperative relapse or stability. Significant differences were observed in the advancement on the right side between groups II, III, and IV and on the left side between groups I, III, and IV. However, the type of surgical intervention showed no significant effect on postoperative relapse and stability. All groups of fixations showed satisfactory stability with irrelevant relapse (< 2 mm or 2°). CONCLUSION: The study demonstrated satisfactory and comparable stability among different fixation groups on patients undergoing mandibular advancement following bilateral split sagittal osteotomy. The results highlighted the importance of considering the degree of advancement when planning orthognathic surgery and managing postoperative outcomes.

The L-shaped Zygomatic Reduction with Oblique or Vertical Resection: Which One is the Optimal Choice?

BACKGROUND: This study aims to investigate the optimal surgical techniques in reduction malarplasty by comparing the difference between the L-shaped osteotomy with vertical and oblique bone resection. METHODS: One hundred and twenty patients who visited our department for L-shaped osteotomy with either vertical (Group Ⅰ) or oblique bone resection (Group Ⅱ) from 2015 to 2021 were retrospectively reviewed. The preoperative and postoperative spiral computed tomography (CT) data were analyzed. The preoperative CT data was also used to simulate the virtual and model surgery. RESULTS: The results showed that a broken-bridge-like structure with a bony gap of 2.86±1.03 mm at the zygomatic arch root was observed in Group Ⅰ, and a mortice and tenon joint structure with a bone overlap of 2.28±0.58 mm was formed in Group Ⅱ. The zygoma in Group Ⅰ displaced significantly in the vertical direction and horizontal direction during the follow-up. Simultaneously, the incidence of complications was higher in Group Ⅰ. In the mechanism analysis through virtual and model surgery, the zygomatic segment was shifted anteriorly and inferiorly in Group Ⅰ, and a bony gap was detected at the zygomatic arch root. Conversely, a superior and posterior movement was performed in Group Ⅱ and it maintained the zygomatic complex integral with bone overlap at the zygomatic arch root upon repositioning. CONCLUSION: This study suggested that L-shaped osteotomy with oblique bone resection could be the optimal choice for reducing zygomatic prominence.

Three-dimensional analysis of zygomatic change after L-shaped reduction malarplasty with bone setback or resection.

PURPOSE: Reduction malarplasty is one of the most popular procedures for esthetic facial contouring in East Asians. The retrospective observational study aimed to analyze the association between the zygomatic change and bone setback or resection to propose quantitative guidance for L-shaped reduction malarplasty based on computed tomographic (CT) images. METHODS: A retrospective observational study was conducted on patients who underwent L-shaped reduction malarplasty with bone resection (Group I) or without bone resection (Group II). The amount of bone setback and resection was calculated. The unilateral width changes of the anterior, middle, and posterior zygomatic regions as well as zygomatic protrusion change were also evaluated. Pearson correlation analysis and linear regression analysis were used to analyze the relationship between the bone setback or resection and the zygomatic changes. RESULTS: Eighty patients who underwent L-shaped reduction malarplasty were included in this study. Significant correlation was observed between the bone setback or resection and the change of anterior, and middle zygomatic width as well as protrusion in both the two groups (P < .001). The correlation between bone setback or resection and the posterior zygomatic width change was not significant (P ＞.05). CONCLUSION: The bone setback or resection of L-shaped reduction malarplasty lead to the anterior and middle zygomatic width and zygomatic protrusion changes. Furthermore, the linear regression equation can be referenced as a guidance for a preoperative surgical plan.

Cupid's Bow Leveling and Preservation of Lip Height and Width: A Modified Rotation-Advancement Technique.

BACKGROUND: Several methods for cleft lip repair have been developed over time, with no clear method considered the standard. In the authors' department, the use of a modified rotation-advancement technique rather than the traditional rotation-advancement technique in unilateral complete cleft lip repair has increased over the past decade. This study aimed to determine which technique provides better outcomes. METHODS: This retrospective study was conducted by analyzing the preoperative and postoperative aesthetic nasal and labial anthropometric measurements of the frontal and basal views of 213 consecutive patients treated between October of 2013 and June of 2019. A total of 141 participants were treated with the traditional rotation-advancement technique, and 72 with the modified rotation-advancement technique. The inclusion criteria were nonsyndromic unilateral complete cleft lip repair with high-resolution, good-quality photographs; no presurgical nasoalveolar molding; no revision in the lip or nose areas; and at least 1 year of follow-up. RESULT: Patients who received the modified rotation-advancement technique had significantly improved Cupid's bow position and orientation ( P < 0.02 and P < 0.01, respectively) and enhanced vertical lip height symmetry ( P < 0.01) while preserving the lip width. The columellar length ( P < 0.03) and angulation ( P < 0.045) were also significantly improved, with enhanced nostril inclination in this group ( P < 0.06). CONCLUSIONS: According to the findings of the current study, modified rotation-advancement technique assisted surgeons in improving symmetrical leveling of the Cupid's bow and significantly aided in correcting lip height without compromising lip width. Moreover, the modified rotation-advancement technique resulted in better aesthetic nasal outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Three-dimensional radiographic assessment of different fixation methods stability after l-shaped osteotomy reduction malarplasty: A comparative retrospective study.

BACKGROUND: Reduction malarplasty (RM) is a common facial contouring procedure among Orientals. Currently, fixation methods selection and placement vectors are controversial. Therefore, this study aimed to evaluate the effect of different zygomatic complex fixation methods on surgical outcomes stability after RM. MATERIALS AND METHODS: In this retrospective study, 60 consented patients (120 operated zygoma) who met inclusion criteria were included. ITK-SNAP and 3D Slicer software were used to measure the displacement of the zygomatic complex using postoperative CTs (T1: one week and T2: six months). The region of interest included zygomatic body fixation methods (ZBFm), namely: two bicortical screws (2LS); an l-shaped plate with one bicortical screw (LPLS); an l-shaped plate with short-wing on the zygoma (LPwZ) and on the maxilla (LPwM), combined with zygomatic arch fixation methods (ZAFm), including Mortice-Tenon (MT); 3-hole plate (3HP); and short screw (SS). ANOVA test was used to compare the displacement values among ZBFm/ZAFm combinations. RESULTS: The 2LS and LPLS groups showed lower displacement than the single l-shaped plate (P< 0.001, P = 0.001), which performed better when the short-wing was fixated on the maxilla (0.9 ± 0.4 mm and 1.2 ± 0.6 mm respectively). CONCLUSION: After RM, the two-bridge fixation methods (2LS and LPLS) provide better stability than the single l-shaped plate. All ZAF methods showed similar stability when combined with 2LS or LPLS as zygomatic body fixation methods.

The importance of remodeling physiological mandibular angle: mandibular "V-line" versus long curved ostectomy.

BACKGROUND: Numerous surgical options for correcting prominent mandibular angles in East Asians have been reported. The objective of this study is to investigate the importance of remodeling physiological mandibular angle by comparing the surgical effects and complications of mandibular "V-line" ostectomy and long curved ostectomy. METHODS: A retrospective study was conducted on patients who underwent either mandibular "V-line" ostectomy (Group I) or long curved ostectomy (Group II). The outcomes were evaluated using computed tomography (CT) images in combination with medical records and photographs. Data were collected preoperatively and at 6- to 12-month intervals postoperatively. Mandibular angle, posterior mandibular ramus height, radian of the ostectomy line, mandibular symmetry as well as patients' complications were investigated. FACE-Q reports of facial appearance and psychosocial parameters were also compared between the two groups. RESULTS: All 106 patients showed improved lower facial contours. Although the postoperative mandibular angle (116.67±7.14°vs 118.31±6.80°, P=.233) and mandibular symmetry (2.36±1.21mm vs 2.56±1.19mm, P=.395) were similar in the two groups, larger postoperative posterior mandibular height and lower radian of the ostectomy line were observed in Group I (P < .001). Physiological mandibular angle was also remodeled in Group I. The gonial deficiency, more soft tissue sagging and significant lower FACE-Q scores of facial appearance were observed in Group II (P < .001). CONCLUSION: In conclusion, "V-line" ostectomy is better suited for achieving a more physiological mandibular angle with less complications compared to mandibular long curved ostectomy. When it comes to mandibular contouring, "V-line" ostectomy may be the preferred option.

Development of postoperative velopharyngeal function in patients with cleft palate.

OBJECTIVE: Patients with a cleft palate often experience a velopharyngeal dysfunction known as velopharyngeal insufficiency (VPI). The purpose of this study was to examine the development of velopharyngeal function (VPF) following primary palatoplasty and the factors that are linked to it. METHODS: A retrospective study was conducted to examine the medical records of patients who had cleft palate, with or without cleft lip (CP ± L) and underwent palatoplasty at a Tertiary Affiliated Hospital between 2004 and 2017. Postoperative evaluation of VPF was conducted at two follow-up times (T1, T2) and was classified as either normal VPF, mild VPI, or moderate/severe VPI. The consistency of VPF evaluations between the two time points was then assessed, and patients were categorized into either the consistent or inconsistent group. The study collected and analyzed data on gender, cleft type, age at operation, follow-up duration, and speech records. RESULTS: The study included 188 patients with CP ± L. Out of these, 138 patients (73.4%) showed consistent VPF evaluations, while 50 patients (26.6%) showed inconsistent VPF evaluations. Among those with VPI at T1 (91 patients), 36 patients (39.6%) had normal VPF at T2. The rate of VPI decreased from 48.40% at T1 to 27.13% at T2, whereas the rate of normal VPF increased from 44.68% at T1 to 68.09% at T2. The consistent group had a significantly younger age at operation (2.90 ± 3.82 vs 3.68 ± 4.02), a longer duration of T1 (1.67 ± 0.97 vs 1.04 ± 0.59), and a lower comprehensive score of speech performance (1.86 ± 1.27 vs 2.60 ± 1.07) than the inconsistent group. CONCLUSIONS: It has been verified that there are changes in the development of VPF over time. Patients who underwent palatoplasty at a younger age were more likely to have confirmed VPF diagnosis at the first evaluation. The duration of follow-up was identified as a critical factor that affects the confirmation of VPF diagnosis.

Correlation of the Chinese velopharyngeal insufficiency-related quality of life instrument and speech in subjects with cleft palate.

OBJECTIVE: Assessment of the hypothesized correlation between the Chinese Velopharyngeal Insufficiency (VPI) Effects on Life Outcomes (VELO) instrument and measured speech parameters. METHODS: A cross-sectional study was conducted in the Oral Clefts Center of West China Hospital of Stomatology between January 2019 and December 2019. Speech parameters including speech intelligibility deficit, VPI severity, VP gap, and need for speech therapy were evaluated by speech-language pathologists. All patients and their parents completed the VELO instrument. The correlation between aforementioned speech parameters and VELO scores was examined utilizing Spearman correlation coefficients. The reliability of VELO test-retest and parent proxy assessment was estimated utilizing intraclass correlation coefficients (ICC). A receiver operating characteristic curve was used to calculate the cutoff VELO score. RESULTS: One hundred and forty patients with their parents were enrolled. The mean age was 12.58 ± 3.72 years. Both parent and youth VELO total and domain scores recorded moderate to strong correlations with all speech parameters (r > -.40, P ˂ .001) except the swallowing domain. Most VELO domain items have shown significant correlations with at least one speech parameter. Moreover, the scales of all speech parameters showed different VELO scores (P Ë‚ .001). The ICC reported test-retest correlation >.73 in all domains, and parent proxy correlation >.63 in most domains except the emotional and perception domains. The cutoff VELO score was 79.04 in parent version and 85.77 in youth version. CONCLUSIONS: The correlations between VELO scores and measured speech parameters have provided evidence for test-retest and parent proxy reliability and criterion and construct validity of the Chinese version of the VELO instrument. A VELO score ≥79.04 (in parent version) or ≥85.77 (in youth version) mostly reflects proper speech-related quality of life. Hence, this instrument could serve as a simple tool to help clinicians understand the social, emotional, and physical influences of VPI.