Denture Labe ling Using QR Codes. A Simplified Technique / Identificación de dentaduras completas utilizando códigos QR. Una técnica simplificada

ABSTRACT Denture identification procedures have multiple benefits for denture wearers. These include prevention of losing or misplacing dentures and forensic identification of victims. A simplified inclusion technique is fully described to label dentures with QR code prints.

RESUMEN Los procedimientos de identificación de dentaduras completas tienen muchos beneficios para los pacientes. Estos incluyen la prevención de la pérdida o confusión de las prótesis y la identificación forense de las víctimas. Se describe en forma detallada una técnica simplificada para identificar dentaduras con códigos QR.

Effect of Preseating, Screw Access Opening, and Vent Holes on Extrusion of Excess Cement at the Crown-Abutment Margin and Associated Tensile Force for Cement-Retained Implant Restorations.

PURPOSE: This study sought to (1) compare the effects of crown preseating prior to cementation, (2) determine whether maintenance of screw access openings on titanium abutments and open vent holes on cast crowns affects the amount of excess cement at the crown-abutment margin, and (3) analyze the associated tensile force after cementation. MATERIALS AND METHODS: Three independent variables were tested: (1) abutment screw access (open or closed), (2) crown coping modification (with or without a vent hole in the palatal aspect), and (3) crown preseating on an abutment analog. Ten implant crown copings were cemented using temporary cement on ten straight implant abutments for each combination of the three independent variables. The amount of excess cement at the crown margins was measured by weight. Axial tensile load was measured 24 hours after cementation. Results were statistically analyzed using linear regression and univariate three-way analysis of variance (α = .05). RESULTS: Open screw access, presence of a vent hole on the crown, and preseating of the crown had significant effects on the amount of excess cement at the crown margin (P < .05). Preseating significantly lowered tensile strength values (P = .001), particularly in specimens with preseating and open screw access (P < .001). There was no significant correlation between excess cement at the margins and tensile strength values. CONCLUSION: Placement of vent holes on the crown or open screw access may be considered for cementing crowns on implant abutments using temporary cement in order to minimize excess cement at the crown margin. A preseating protocol is not advisable, either alone or combined with open screw access, since it significantly reduces the retentive strength of cemented restorations (P < .001).