Resumen de Radiographic Appearance of Interocclusal Record Materials for Cone Beam Computed Tomography-Guided Implant Surgeries

Vrinda V. Mohunta, Shereen S. Azer, Do-Gyoon Kim, Edwin A. McGlumphy

• Purpose: To select an ideal interocclusal record material for cone beam computed tomography (CBCT)-guided implant surgery based on the material's radiodensity on the scan.

  Materials and Methods: Twelve commonly used interocclusal record materials were used for this investigation: two were waxes, one was polyether, and nine were polyvinyl-siloxane-type materials. A scan template was fabricated by duplicating existing dentures in Ortho-Jet acrylic resin mixed with 30% barium powder for the teeth and 10% barium powder for the denture base between the teeth and the tissue. An interocclusal record was fabricated with each material, and the same template was used to obtain a CBCT scan with an ICAT machine (Imaging Sciences International) at 0.3 voxel and 14-bit depth settings. Twelve CBCT scans were obtained and analyzed. The radiopacity of the barium teeth was used as a control and was compared with the opacity of the 12 materials using a paired t test. A post hoc analysis of variance (ANOVA) test was used to compare the densities of the various materials with each other.

  Results: There was a statistically significant difference between the radiopacity of barium teeth (gray value: 1,959.475) and that of Modelling Wax (gray value: 750; P = .0026), Aluwax (gray value: 795.22; P = .0022), Blu-Bite CT (gray value: 1,105; P = .005), Ramitec (gray value: 1,105.3; P = .08), Memosil 2 (gray value: 1,202; P = .01) followed by Reprosil (gray value: 1,407.73; P = .01). Compared with the barium teeth, there was no statistically significant difference between the densities of Futar D (gray value: 1,866.5; P = .51), Jet Bite (gray value: 1,660.04; P = .08), Lab-Putty (gray value: 1,402.14; P = .19), and Memoreg 2 (gray value: 1,754.72; P = .1). The highest radiodensity was seen with Blu-Mousse (gray value: 2,949; P = .007) and Take 1 (gray value: 2,229.85; P = .025), which were also significantly different from the density of the barium teeth but in the opposite direction, making them more opaque.

  Conclusion: Within the limitations of this in vitro study, the most radiolucent appearance of Modelling Wax, Aluwax, Memosil 2, Blu-Bite CT, and Ramitec made them the suitable materials of choice of those tested, as the interocclusal registration record during CBCT scanning allowed clear visualization of barium teeth.