Research and Education| Volume 129, ISSUE 6, P896.e1-896.e8, June 2023

Download started.


Evaluation of the passive fit and definitive marginal fit of prefabricated and conventional CAD-CAM milled titanium bars with a fully guided surgical protocol: An in vitro study


      Statement of problem

      Computer-aided design and computer-aided manufacturing (CAD-CAM) milled titanium bars have shown good clinically acceptable passive fit and definitive marginal fit; however, investigations into the passive fit and definitive marginal fit of prefabricated CAD-CAM milled titanium bars are lacking.


      The purpose of this in vitro study was to compare and evaluate the passive fit and definitive marginal fit of prefabricated and conventional CAD-CAM milled titanium bars.

      Material and methods

      A total of 10 polyurethane radiopaque anatomic completely edentulous mandibular models had implants (Biohorizons) placed in the left and right canine and second premolar positions using a 3-dimensionally printed fully guided surgical guide. For the conventional bars, impressions were made, and casts were scanned and exported to a software program (exocad 3.0). For the prefabricated bars, the surgical plans were exported from the software program directly. The Sheffield test was used to evaluate the passive fit of the bars, and marginal fit was evaluated with a scanning electron microscope at ×50 magnification. The Shapiro-Wilk test was used to determine that the data were normally distributed; the data are presented using mean and standard deviation. Group comparisons were made with the independent t test (α=.05).


      The passive and marginal fit of the conventional bars was better than that of the prefabricated bars. The mean ±standard deviation values for passive fit were 75.2 ±13.7 μm for conventional bars and 94.7 ±16.0 μm for prefabricated bars (P<.001). A statistically significant difference (P<.001) was also found between the marginal fit of the conventional bars 18.7 ±6.1 μm and the prefabricated bars 56.3 ±13.0 μm.


      Conventional CAD-CAM milled titanium bars had a better passive and marginal fit than prefabricated CAD-CAM milled titanium bars; however, both had clinically acceptable passive fit ranging from 75.2 to 94.7 μm and definitive marginal fit ranging from 18.7 to 56.3 μm.
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Journal of Prosthetic Dentistry
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Chen C.
        • Lai H.
        • Zhu H.
        • Gu X.
        Digitally prefabricated versus conventionally fabricated implant-supported full-arch provisional prosthesis: a retrospective cohort study.
        BMC Oral Health. 2022; 22: 335
        • Rosenfeld A.L.
        • Mandelaris G.A.
        • Tardieu P.B.
        Prosthetically directed implant placement using computer software to ensure precise placement and predictable prosthetic outcomes. Part 1: diagnostics, imaging, and collaborative accountability.
        Int J Periodontics Restorative Dent. 2006; 26: 215-221
        • Vercruyssen M.
        • Hultin M.
        • Van Assche N.
        • Svensson K.
        • Naert I.
        • Quirynen M.
        Guided surgery: accuracy and efficacy.
        Periodontol 2000. 2014; 66: 228-246
        • D'haese J.
        • Van De Velde T.
        • Elaut L.
        • De Bruyn H.
        A prospective study on the accuracy of mucosally supported stereolithographic surgical guides in fully edentulous maxillae.
        Clin Oral Implants Res. 2012; 14: 293-303
        • Tahmaseb A.
        • Wu V.
        • Wismeijer D.
        • Coucke W.
        • Evans C.
        The accuracy of static computer-aided implant surgery: a systematic review and meta-analysis.
        Clin Oral Implants Res. 2018; 29: 416-435
        • Ortorp A.
        • Jemt T.
        Clinical experiences of computer numeric control-milled titanium frameworks supported by implants in the edentulous jaw: a 5-year prospective study.
        Clin Implant Dent Relat Res. 2004; 6: 199-209
        • Hedkvist L.
        • Mattsson T.
        • Helldén L.B.
        Clinical performance of a method for the fabrication of implant-supported precisely fitting titanium frameworks: a retrospective 5- to 8-year clinical follow-up study.
        Clin Implant Dent Relat Res. 2004; 6: 174-180
        • Baroudi K.
        • Ibraheem S.N.
        Assessment of chair-side computer-aided design and computer-aided manufacturing restorations: a review of the literature.
        J Int Oral Health. 2015; 7: 96-104
        • Boitelle P.
        • Mawussi B.
        • Tapie L.
        • Fromentin O.
        A systematic review of CAD-CAM fit restoration evaluations.
        J Oral Rehabil. 2014; 41: 853-874
        • Abduo J.
        Fit of CAD-CAM implant frameworks: a comprehensive review.
        J Oral Implantol. 2014; 40: 758-766
        • Chochlidakis K.M.
        • Papaspyridakos P.
        • Geminiani A.
        • Chen C.J.
        • Feng I.J.
        • Ercoli C.
        Digital versus conventional impressions for fixed prosthodontics: a systematic review and meta-analysis.
        J Prosthet Dent. 2016; 116: 184-190
        • Ahlholm P.
        • Sipilä K.
        • Vallittu P.
        • Jakonen M.
        • Kotiranta U.
        Digital versus conventional impressions in fixed prosthodontics: a review.
        J Prosthodont. 2018; 27: 35-41
        • Brånemark P.-I.
        • Zarb G.A.
        • Albrektsson T.
        Tissue-integrated Prostheses: Osseointegration in Clinical Dentistry.
        Quintessence, Chicago, IL1985: 99-115
        • Sorrentino R.
        • Gherlone E.F.
        • Calesini G.
        • Zarone F.
        Effect of implant angulation, connection length, and impression material on the dimensional accuracy of implant impressions: an in vitro comparative study.
        Clin Implant Dent Relat Res. 2010; 12: e63-e76
        • Jemt T.
        • Rubenstein J.E.
        • Carlsson L.
        • Lang B.R.
        Measuring fit at the implant prosthodontic interface.
        J Prosthet Dent. 1996; 75: 314-325
        • Wee A.G.
        • Aquilino S.A.
        • Schneider R.L.
        Strategies to achieve fit in implant prosthodontics: a review of the literature.
        Int J Prosthodont. 1999; 12: 167-178
        • Jemt T.
        Failures and complications in 391 consecutively inserted fixed prostheses supported by Brånemark implants in edentulous jaws: a study of treatment from the time of prosthesis placement to the first annual checkup.
        Int J Oral Maxillofac Implants. 1991; 6: 270-276
        • Cohen S.R.
        • Orenstein J.H.
        The use of attachments in combination of implant and natural tooth fixed partial dentures-A technical report.
        Int J Oral Maxillofac Implants. 1994; 9: 230-234
        • Brunski J.B.
        Influence of biomechanical factors at the bone-biomaterial interface.
        Bone-Biomaterial Interface. 1991; 2: 391-403
        • Pilliar R.M.
        • Lee J.M.
        • Maniatopoulos C.
        Observations on the effect of movement on bone ingrowth into poroussurfaced implants.
        Clin Orthop Relat Res. 1986; 208: 108-113
        • Jemt T.
        • Book K.
        Prosthesis misfit and marginal bone loss in edentulous implant patients.
        Int J Oral Maxillofac Implants. 1996; 11: 620-625
        • Klineberg I.J.
        • Murray G.M.
        Design of superstructures for osseointegrated fixtures.
        Swed Dent J Suppl. 1985; 28: 63-69
        • Kan J.Y.
        • Rungcharassaeng K.
        • Bohsali K.
        • Goodacre C.J.
        • Lang B.R.
        Clinical methods for evaluating implant framework fit.
        J Prosthet Dent. 1999; 81: 7-13
        • Vieira D.M.
        • Sotto-Maior B.S.
        • de Souza Barros C.A.
        • Reis E.S.
        • Francischone C.E.
        Clinical accuracy of flapless computer-guided surgery for implant placement in edentulous arches.
        Int J Oral Maxillofac Implants. 2013; 28: 1347-1351
        • Koch G.K.
        • Gallucci G.O.
        • Lee S.J.
        Accuracy in the digital workflow: from data acquisition to the digitally milled cast.
        J Prosthet Dent. 2016; 115: 749-754
        • Rocci A.
        • Martignoni M.
        • Gottlow J.
        Immediate loading in the maxilla using flapless surgery, implants placed in predetermined positions, and prefabricated provisional restorations: a retrospective 3-year clinical study.
        Clin Implant Dent Relat Res. 2003; 5: 29-36
        • Johansson B.
        • Friberg B.
        • Nilson H.
        Digitally planned, immediately loaded dental implants with prefabricated prostheses in the reconstruction of edentulous maxillae: a 1-year prospective, multicenter study.
        Clin Implant Dent Relat Res. 2009; 11: 194-200
        • Johansson B.
        • Friberg B.
        • Nilson H.
        Digitally planned, immediately loaded dental implants with prefabricated prostheses in the reconstruction of edentulous maxillae: a 3-Year Prospective, multicenter study.
        J Oral Maxillofac Surg. 2011; 69: e29
        • Allum S.R.
        Immediately loaded full-arch provisional implant restorations using CAD-CAM and guided placement: Maxillary and mandibular case reports.
        Br Dent J. 2008; 204: 377-381
        • IBM Corp. Released
        IBM SPSS Statistics for Windows, Version 23.0.
        IBM Corp, Armonk, NY2015
        • Rosner B.
        Fundamentals of biostatistics.
        Cengage Learning; Boston, MA., 2015
        • Cassetta M.
        • Di Mambro A.
        • Giansanti M.
        • Stefanelli L.V.
        • Cavallini C.
        The intrinsic error of a stereolithographic surgical template in implant guided surgery.
        Int J Oral Maxillofac Surg. 2013; 42: 264-275
        • Ochi M.
        • Kanazawa M.
        • Sato D.
        • Kasugai S.
        • Hirano S.
        • Minakuchi S.
        Factors affecting accuracy of implant placement with mucosa-supported stereolithographic surgical guides in edentulous mandibles.
        Comput Biol Med. 2013; 43: 1653-1660
        • Cassetta M.
        • Giansanti M.
        • Di Mambro A.
        • Stefanelli L.V.
        Accuracy of positioning of implants inserted using a mucosa-supported stereolithographic surgical guide in the edentulous maxilla and mandible.
        Int J Oral Maxillofac Implants. 2014; 29: 1071-1078
        • Sahin S.
        • Cehreli M.C.
        The significance of passive framework fit in implant prosthodontics: current status.
        Implant Dent. 2001; 10: 85-92
        • Carlsson L.
        Built-in strain and untoward forces are the inevitable companions of prosthetic misfit.
        Nobelpharma News. 1994; 8: 5
        • Pan Y.
        • Tsoi J.K.
        • Lam W.Y.
        • Pow E.H.
        Implant framework misfit: a systematic review on assessment methods and clinical complications.
        Clin Implant Dent Relat Res. 2021; 23: 244-258
        • D'haese J.
        • Van De Velde T.
        • Komiyama A.
        • Hultin M.
        • De Bruyn H.
        Accuracy and complications using computer-designed stereolithographic surgical guides for oral rehabilitation by means of dental implants: a review of the literature.
        Clin Implant Dent Relat Res. 2012; 14: 321-335
        • Sannino G.
        • Bollero P.
        • Barlattani A.
        • Gherlone E.
        A retrospective 2-year clinical study of immediate prosthetic rehabilitation of edentulous jaws with four implants and prefabricated bars.
        J Prosthodont. 2017; 26: 387-394