Journal of Prosthetic Dentistry
Research and Education| Volume 128, ISSUE 2, P219-224, August 2022

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Percentage of mesh reduction appropriate for designing digital obturator prostheses on personal computers

Published:February 15, 2021DOI:


      Statement of problem

      Computer-aided design (CAD) of maxillofacial prostheses is a hardware-intensive process. The greater the mesh detail is, the more processing power is required from the computer. A reduction in mesh quality has been shown to reduce workload on computers, yet no reference value of reduction is present for intraoral prostheses that can be applied during the design.


      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.


      The reduction in file size was directly proportional to the amount of mesh reduction. There were minute yet insignificant differences in volume (P>.05) across all mesh groups, with significant differences (P<.001) in HD. The differences were, however, only found with DB1. DSC showed a progressive dissimilarity until DB25 (0.17%), after which the increase was more prominent (0.46% to 4.02%).


      A reduction of up to 75% polygons (25% of the original mesh) was effectively carried out on simulated casts without substantially affecting the amount of similarity in volume and geometry.
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        • Agathos A.
        • Pratikakis I.
        • Perantonis S.
        • Sapidis N.
        • Azariadis P.
        3D mesh segmentation methodologies for CAD applications.
        Comput Aided Des Appl. 2007; 4: 827-841
        • Mahoney J.J.
        • Tatum C.B.
        Construction site applications of CAD.
        J Constr Eng Manag. 1994; 120: 617-631
        • Farook T.H.
        • Jamayet N.B.
        • Abdullah J.Y.
        • Rajion Z.A.
        • Alam M.K.
        A systematic review of the computerized tools & digital techniques applied to fabricate nasal, auricular, orbital and ocular prostheses for facial defect rehabilitation.
        J Stomatol Oral Maxillofac Surg. 2020; 121: 268-277
        • Farook T.H.
        • Jamayet N.B.
        A review of prostheses fabricated for rehabilitation of nasal septal defect using digital workflow.
        Otorinolaryngologia. 2020; 70
        • Schroeder W.J.
        • Zarge J.A.
        • Lorensen W.E.
        Decimation of triangle meshes.
        in: Siggraph. Association for Computer Machinery, New York1992: 65-70
        • Farook T.H.
        • Mousa M.A.
        • Jamayet N.B.
        Method to control tongue position and open source image segmentation for cone-beam computed tomography of patients with large palatal defect to facilitate digital obturator design.
        J Oral Maxillofac Surg Med Pathol. 2020; 32: 61-64
        • Farook T.H.
        • Jamayet N.B.
        • Abdullah J.Y.
        • Asif J.A.
        • Rajion Z.A.
        • Alam M.K.
        Designing 3D prosthetic templates for maxillofacial defect rehabilitation: a comparative analysis of different virtual workflows.
        Comput Biol Med. 2020; 118: 103646
        • Egger J.
        • Kapur T.
        • Fedorov A.
        • Pieper S.
        • Miller J.V.
        • Veeraraghavan H.
        • et al.
        GBM volumetry using the 3D Slicer medical image computing platform.
        Sci Rep. 2013; 3: 1364
        • Abdullah J.
        • Abdullah A.
        • Hadi H.
        • Husein A.
        • Rajion Z.
        Comparison of STL skull models produced using open-source software versus commercial software.
        Rapid Prototyp J. 2019; 25: 1585-1591
        • Sharma N.
        • Cao S.
        • Msallem B.
        • Kunz C.
        • Brantner P.
        • Honigmann P.
        • et al.
        Effects of steam sterilization on 3D printed biocompatible resin materials for surgical guides—an accuracy assessment study.
        J Clin Med. 2020; 9: 1506
        • Guindon B.
        • Zhang Y.
        Application of the Dice coefficient to accuracy assessment of object-based image classification.
        Can J Remote Sens. 2017; 43: 48-61
        • Lo Russo L.
        • Caradonna G.
        • Biancardino M.
        • De Lillo A.
        • Troiano G.
        • Guida L.
        Digital versus conventional workflow for the fabrication of multiunit fixed prostheses: a systematic review and meta-analysis of vertical marginal fit in controlled in vitro studies.
        J Prosthet Dent. 2019; 122: 435-440
        • Zhao L.
        • Chubb C.
        The size-tuning of the face-distortion after-effect.
        Vision Res. 2001; 41: 2979-2994