PURPOSE: The purpose of this simulation study was to establish a reference percentage value that can be used to effectively reduce the size and polygons of the 3D mesh without drastically affecting the dimensions of the prosthesis itself.

MATERIAL AND METHODS: Fifteen different maxillary palatal defects were simulated on a dental cast and scanned to create 3D casts. Digital bulbs were fabricated from the casts. Conventional bulbs for the defects were fabricated, scanned, and compared with the digital bulb to serve as a control. The polygon parameters of digital bulbs were then reduced by different percentages (75%, 50%, 25%, 10%, 5%, and 1% of the original mesh) which created a total of 105 meshes across 7 mesh groups. The reduced mesh files were compared individually with the original design in an open-source point cloud comparison software program. The parameters of comparison used in this study were Hausdorff distance (HD), Dice similarity coefficient (DSC), and volume.

MATERIALS AND METHODS: An auricular prosthesis, a complete denture, and anterior and posterior crowns were constructed using conventional methods and laser scanned to create computerized 3D meshes. The meshes were optimized independently by four computer-aided design software (Meshmixer, Meshlab, Blender, and SculptGL) to 100%, 90%, 75%, 50%, and 25% levels of original file size. Upon optimization, the following parameters were virtually evaluated and compared; mesh vertices, file size, mesh surface area (SA), mesh volume (V), interpoint discrepancies (geometric similarity based on virtual point overlapping), and spatial similarity (volumetric similarity based on shape overlapping). The influence of software and optimization on surface area and volume of each prosthesis was evaluated independently using multiple linear regression.

RESULTS: There were clear observable differences in vertices, file size, surface area, and volume. The choice of software significantly influenced the overall virtual parameters of auricular prosthesis [SA: F(4,15) = 12.93, R2 = 0.67, p < 0.001. V: F(4,15) = 9.33, R2 = 0.64, p < 0.001] and complete denture [SA: F(4,15) = 10.81, R2 = 0.67, p < 0.001. V: F(4,15) = 3.50, R2 = 0.34, p = 0.030] across optimization levels. Interpoint discrepancies were however limited to <0.1mm and volumetric similarity was >97%.

STUDY DESIGN: The study is a prospective observational study which included 122 patients who had symptomatic POP stage III and IV. AvaultaPlus™ (collagen coated, CC group) was compared to Perigee™ (non collagen coated, NC group). Introital ultrasound morphology, measure of neovascularization by color Doppler and clinical outcomes were assessed. Student t test was used for comparison of pre- and post-operation continuous data (p value of <0.05).

RESULTS: A total of 110 (CC group=50, NC group=60) women completed the study. A woman in the CC group developed ureteral injury. Both groups had comparable morphologic and clinical outcomes however, the onset of changes in mesh thickness and neovascularization occurred earlier in the NC group (1 month) compared to the CC group (6 months to 1 year).

CASE REPORT: A series of three patients who developed recurrent pelvic organ prolapse more than 9 years after sacrocolpopexy. A 50-year-old and two 77-year-old patients who presented with recurrent pelvic organ prolapse at 9, 15 and 17 years, respectively after the primary abdominal sacrocolpopexy were managed by transvaginal mesh surgery.

MATERIALS AND METHODS: The charts of 796 women who underwent pelvic organ prolapse (POP) surgery from July 2006 to January 2012 in Chang Gung Memorial Hospitals were reviewed. We included women who presented with advanced cuff eversion and treated with TVM surgery. Data were analysed after three years post-surgery. Descriptive statistics were used for demographic and perioperative data. The paired-samples t test was used for comparison of preoperative and postoperative continuous data. The outcomes measured were objective cure (POP-Q stage ≤ 1) and subjective cure (negative response to question 2 and 3 on POPDI-6).

RESULTS: A total of 97 patients was analysed. 61 patients had TVM-A and 36 patients had TVM-AP insertion. Mean follow-up was 52 months. The objective cure rate for TVM-AP was significantly higher than TVM-A, 94.4% versus 80.3%. TVM-AP also showed a higher subjective cure rate (91.7%) though there was no significant difference from TVM-A (p = 0.260). The mesh extrusion rate was low at 3.1% with no major complications seen. In TVM-A the blood loss was lesser and the operation time was shorter.