Page 125 - Craniomaxillofacial Implant Surgery - Jeroen P.J. Dings

General discussion and future perspectives
Furthermore, also the clinical impact of possible influence of voxel sizes on measurement precision is questionable14,15. Brightness and contrast settings significantly influenced linear measurements of bone width for CBCT images (p<0.0015) and inter-observer variation on MDCT imaging (p <.029). However, the difference only comprised 0.14 millimeter and 0.05 millimeter, respectively.
Another limitation of the present study was that only one imaging software package was used. However, Tolentino et al. and Wismeijer et al. (2018) showed that the different software protocols do not influence CBCT accuracy for linear measurements in multiplanar reconstructions2,15.
In conclusion, the results in Chapter 2 prove that CBCT and MDCT scans showed a submillimeter overestimation of the anatomical truth for preoperative evaluation of implant sites at the orbital, nasal and auricular region. This is in accordance with our clinical experience where during surgery, often less bone volume is available than presumed.
Reliability and accuracy of skin-supported surgical templates for computer-planned
craniofacial implant placement, a comparison between surgical templates: with and
without bony fixation (Chapter 3).
This human cadaveric study was conducted to evaluate the accuracy of computer-aided
designed stereolithographic skin-supported surgical templates with and without bone
fixation pins in transferring the virtually planned implant positions to the clinical environment. 7
Computer-aided design and manufacturing (CAD/CAM) has been described in dental implant treatment extensively and has become an accepted standard of care for preoperative planning and prosthesis design2,16. Literature shows that accuracy is considerably improved with guided implantation when compared to conventional template or freehand implant placement17. Especially for difficult anatomical areas, such as the floor of the nose or orbital rim showing thin, low-density bone, strategic and accurate placement of CMF implants is crucial for an optimal clinical outcome16.
Skin-supported surgical templates were developed in this study with the aim of improving predictability and accuracy during surgical implant placement both in the auricular-, nasal- and orbital region. A disadvantage of these skin-supported templates
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