Influence of matrix type on surface roughness of three resins for provisional crowns and fixed partial dentures.
OBJECTIVE
This study evaluated the effect of matrix type on the surface roughness of resins for provisional crowns and fixed partial dentures.


METHODS
Ninety specimens of two acrylic resins (Trim II, Tab2000) and one bis-acryl composite (Protemp II Garant) were fabricated using one of three matrices: irreversible hydrocolloid (Cavex CA37), poly(vinyl siloxane) (Aquasil) or vacuum-formed matrix (Bio-flow Hard). The sample size for each resin-matrix combination was 10. The vestibular face of one natural maxillary central incisor was used as a model to fabricate all the specimens, following the custom fabrication technique. The average roughness measurements, Ra (mum), were obtained using a profilometer, and the data were analyzed using Kruskal-Wallis and Mann-Whitney U-tests. The results were contrasted against the surface roughness of the tooth using a one-sample t-test.


RESULTS
Aquasil and vacuum-formed matrix had a smoother surface than Cavex CA37 regardless of the resin tested (p < 0.05). Protemp II Garant had the smoothest surface regardless of the matrix used, with no significant differences when polymerized against the three different matrices. Trim II polymerized against Cavex CA37 had a rougher (p < 0.05) surface than Aquasil or vacuum-formed matrix. Tab2000 had the smoothest surface (p < 0.05) when polymerized against a vacuum-formed matrix.


CONCLUSIONS
There is no universal matrix that produces the smoothest surface: this depends on the compatibility between the resin and the matrix. Protemp II Garant polymerized against Cavex CA37 matrix yields a surface that is smooth enough not to require polishing unless this surface is adjusted.
Ayuso-Montero
Raul
R
Department of Prosthodontics, Faculty of Dentistry, University of Barcelona, Spain.
Martinez-Gomis
Jordi
J
Lujan-Climent
Mar
M
Salsench
Juan
J
Peraire
Maria
M
D000180:Acrylic Resins / Q000737:chemistry; D000464:Alginates / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D003442:Crowns; D003760:Dental Impression Materials / Q000737:chemistry; D003761:Dental Impression Technique / Q000295:instrumentation*; D003764:Dental Materials / Q000737:chemistry*; D017267:Dental Prosthesis Design / Q000295:instrumentation; D003794:Dental Restoration, Temporary; D003779:Denture Design / Q000295:instrumentation; D003830:Denture, Partial, Fixed; D003833:Denture, Partial, Temporary; D006801:Humans; D008422:Materials Testing; D011109:Polymethacrylic Acids / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry; D012117:Resins, Synthetic / Q000737:chemistry*; D012833:Siloxanes / Q000737:chemistry; D013499:Surface Properties
D000180:Acrylic Resins; D000464:Alginates; D003188:Composite Resins; D003760:Dental Impression Materials; D003764:Dental Materials; D011109:Polymethacrylic Acids; D011145:Polyvinyls; D012117:Resins, Synthetic; D012833:Siloxanes; C480691:aquasil; C050135:cavex; C091347:vinyl ethyl methacrylate; C069714:Protemp