Resin polymerisation shrinkage reduces the congruence of the denture base with denture-bearing tissues and thereby decreases the retention of conventionally fabricated dentures. CAD/CAM denture manufacturing is a subtractive process, and polymerisation shrinkage is not an issue anymore. Therefore, CAD/CAM dentures are assumed to show a higher denture base congruence than conventionally fabricated dentures. It has been the aim of this study to test this hypothesis.
CAD/CAM dentures provided by four different manufacturers (AvaDent, Merz Dental, Whole You, Wieland/Ivoclar) were generated from ten different master casts. Ten conventional dentures (pack and press, long-term heat polymerisation) made from the same master casts served as control group. The master casts and all denture bases were scanned and matched digitally. The absolute incongruences were measured using a 2-mm mesh.
Conventionally fabricated dentures showed a mean deviation of 0.105 mm, SD = 0.019 from the master cast. All CAD/CAM dentures showed lower mean incongruences. From all CAD/CAM dentures, AvaDent Digital Dentures showed the highest congruence with the master cast surface with a mean deviation of 0.058 mm, SD = 0.005. Wieland Digital Dentures showed a mean deviation of 0.068 mm, SD = 0.005, Whole You Nexteeth prostheses showed a mean deviation of 0.074 mm, SD = 0.011 and Baltic Denture System prostheses showed a mean deviation of 0.086 mm, SD = 0.012.
CAD/CAM produces dentures with better fit than conventional dentures.
The present study explains the clinically observed enhanced retention and lower traumatic ulcer-frequency in CAD/CAM dentures.
de Baat C, van Aken AA, Mulder J, Kalk W (1997) “Prosthetic condition” and patients’ judgment of complete dentures. J Prosthet Dent 78(5):472–478. https://doi.org/10.1016/S0022-3913(97)70062-3 CrossRefPubMed
Felton D, Cooper L, Duqum I, Minsley G, Guckes A, Haug S, Meredith P, Solie C, Avery D, Chandler ND (2011) Evidence-based guidelines for the care and maintenance of complete dentures: a publication of the American College of Prosthodontists. J Am Dent Assoc 142(Suppl 1):1S–20S. https://doi.org/10.14219/jada.archive.2011.0067 CrossRefPubMed
Darvell BW, Clark RK (2000) The physical mechanisms of complete denture retention. Br Dent J 189(5):248–252 PubMed
Fueki K, Yoshida E, Igarashi Y (2011) A structural equation model relating objective and subjective masticatory function and oral health-related quality of life in patients with removable partial dentures. J Oral Rehabil 38(2):86–94. https://doi.org/10.1111/j.1365-2842.2010.02134.x CrossRefPubMed
Murray MD, Darvell BW (1989) Reappraisal of the physics of denture retention. Int J Prosthodont 2(3):234–242 PubMed
Ansari IH (1997) Establishing the posterior palatal seal during the final impression stage. J Prosthet Dent 78(3):324–326. https://doi.org/10.1016/S0022-3913(97)70034-9 CrossRefPubMed
Goodacre CJ, Garbacea A, Naylor WP, Daher T, Marchack CB, Lowry J (2012) CAD/CAM fabricated complete dentures: concepts and clinical methods of obtaining required morphological data. J Prosthet Dent 107(1):34–46. https://doi.org/10.1016/S0022-3913(12)60015-8 CrossRefPubMed
Kattadiyil MT, Goodacre CJ, Baba NZ (2013) CAD/CAM complete dentures: a review of two commercial fabrication systems. J Calif Dent Assoc 41(6):407–416 PubMed
Kattadiyil MT, Jekki R, Goodacre CJ, Baba NZ (2015) Comparison of treatment outcomes in digital and conventional complete removable dental prosthesis fabrications in a predoctoral setting. J Prosthet Dent 114(6):818–825. https://doi.org/10.1016/j.prosdent.2015.08.001 CrossRefPubMed
Goodacre BJ, Goodacre CJ, Baba NZ, Kattadiyil MT (2016) Comparison of denture base adaptation between CAD-CAM and conventional fabrication techniques. J Prosthet Dent 116(2):249–256. https://doi.org/10.1016/j.prosdent.2016.02.017 CrossRefPubMed
Gale MS, Darvell BW (1999) Thermal cycling procedures for laboratory testing of dental restorations. J Dent 27(2):89–99. https://doi.org/10.1016/S0300-5712(98)00037-2 CrossRefPubMed
Dental Wings Inc. (2016) 7 Series User Manual EN 2016–01-15 v. 3.1.1. http://ifu.straumann.com/content/dam/internet/straumann_ifu/cares/7Series_UserManual_v3.1.1_EN_2016-01-15_high.pdf. Accessed 3 June 2017
Ender A, Mehl A (2013) Influence of scanning strategies on the accuracy of digital intraoral scanning systems. Int J Comput Dent 16(1):11–21 PubMed
Schaefer O, Decker M, Wittstock F, Kuepper H, Guentsch A (2014) Impact of digital impression techniques on the adaption of ceramic partial crowns in vitro, vol 42. J Dent, pp 677–683. https://doi.org/10.1016/j.jdent.2014.01.016
AlHelal A, AlRumaih HS, Kattadiyil MT, Baba NZ, Goodacre CJ (2017) Comparison of retention between maxillary milled and conventional denture bases: a clinical study. J Prosthet Dent 117(2):233–238. https://doi.org/10.1016/j.prosdent.2016.08.007 CrossRefPubMed
- CAD/CAM produces dentures with improved fit
- Springer Berlin Heidelberg
Clinical Oral Investigations
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