Surfaces of ceramic crowns are modified several times Background: before being exposed to wear in the oral cavity. Grinding and different finishing procedures may be associated with teeth wear due to increased surface roughness. Limited data is available with regard to the effect of polishing procedures on the surface roughness and wear behavior of ceramic crowns. This study was conducted to assess the influence of polished and polished-ground-repolished surface finish on the roughness and wear performance of three ceramic crowns.36 natural 1st molar teeth were prepared using a CNC milling Methods: machine and classified into three groups (n=12/group): zirconia,

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To evaluate the safety and the efficacy of accelerated corneal cross-linking with two different energy protocols. Design Prospective, randomized, interventional study. Patients and Methods: 48 eyes of 26 patients aged 18-38 years with progressive keratoconus. Group A underwent accelerated cross-linking (24 eyes, 5.4 J/cm2), Group B treated with higher ultraviolet-A irradiance (24 eyes, 7.2 J/cm2). Changes in corrected distance visual acuity (CDVA), keratometric data, densitometric data, and specular microscopy were recorded preoperatively and at the 1st, 3rd, and 6th month postoperatively. One month postoperatively, the demarcation line was measured using anterior segment optical coherence tomography. Results: A mean corneal demarcation line was 231.43±27.18 μm in group A and 282.3±21.4 μm in group B and was significantly deeper in group B (P<0.05). Corneal densitometry in the anterior corneal layers was peaked at the 3rd month follow up in both groups. In contrast, middle and posterior stromal layers peaked at the 6th month in both groups (P<0.05). There were no statistically significant changes in CDVA, keratometric values, and endothelial cells in the two groups. Conclusion: We found that accelerated and modified accelerated cross-linking protocols were effective and safe in halting keratoconus progression after a follow-up period of 6 months.