Ricerc@Sapienza

Introduction: Previously published studies have deeply investigated the characteristics of flexural and torsional resistance of nickel-titanium rotary instruments, but none of them investigated the relationship between the 2 stresses. The objective of the present study was to evaluate the influence of flexural stresses over torsional resistance. Methods: Sixty S-One 20.04 files (Fanta Dental, Shanghai, China) were used in the present study (N = 60) and divided into 3 test groups of 20 files.

Maxillo-mandibular reconstruction in pediatric patients involves particular functional and cosmetic implications. Attention is required for the craniofacial growth over time, involvement of the permanent dentition, facial symmetry, and donor site morbidity. Our aim is to identify the best reconstructive options for maxilla-mandibular defects in children (<18 years) based on our experience with 25 pediatric patients. We believe that reconstruction has to be performed at the same time as resection in pediatric patients.

The alkali-activation of titanium (Ti) surfaces performed in a heated sodium hydroxide (NaOH) aqueous solution, results in a porous layer rich in hydroxyl (OH) groups, the structure and porosity of which strongly depend on the reaction time and NaOH concentration used.