The energy state of endosteal implants is dependent on the material, manufacturing technique, cleaning procedure, sterilization method, and surgical manipulation. An implant surface carrying a positive charge renders hydrophilic properties, thereby facilitating the absorption of vital plasma proteins crucial for osteogenic interactions. Techniques to control the surface charge involve processes like oxidation, chemical and topographical adjustments as well as the application of nonthermal plasma (NTP) treatment. NTP at atmospheric pressure and at room temperature can induce chemical and/or physical reactions that enhance wettability through surface energy changes. NTP has thus been used to modify the oxide layer of endosteal implants that interface with adjacent tissue cells and proteins. Results have indicated that if applied prior to implantation, NTP strengthens the interaction with surrounding hard tissue structures during the critical phases of early healing, thereby promoting rapid bone formation. Also, during this time period, NTP has been found to result in enhanced biomechanical fixation. As such, the application of NTP may serve as a practical and reliable method to improve healing outcomes. This review aims to provide an in-depth exploration of the parameters to be considered in the application of NTP on endosteal implants. In addition, the short- and long-term effects of NTP on osseointegration are addressed, as well as recent advances in the utilization of NTP in the treatment of periodontal disease.
Current evidence suggests that achieving the desired level of osseointegration necessitates a hierarchical approach to implant design. This is particularly relevant for osseointegration around implant systems such as those presenting vertical decompression chambers and acid-etched surfaces which could further be augmented by non-thermal plasma (NTP) treatment. Three implant systems were compared in this study: (i) ND (GM Helix Acqua Implant; Neodent®, Curitiba, PR, Brazil—hybrid, acid-etched thread design treated with isotonic sodium chloride solution), (ii) Sin (Epikut Plus; S.I.N. Implant System, São Paulo, Brazil—V-shaped, acid-etched thread design treated with nano-hydroxyapatite), and (iii) Mp (Maestro; Implacil De Bortoli, São Paulo, Brazil—buttress, acid-etched thread design with decompressing vertical chambers). The ND and Sin implants were used directly as supplied by the manufacturer. For the Mp implants, the manufacturer-supplied surface was subjected to supplemental acid etching with 37% hydrochloric acid followed by Argon-based NTP treatment administered with a pulsed plasma generator prior to implantation into the iliac crest of n = 12 adult female sheep. Histomorphometric analysis was conducted at 3- and 12-week post-implantation (n = 6 sheep per time point) to assess bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO). After 3 weeks in vivo, the healing chambers of all implant groups consisted predominantly of newly forming woven bone. By 12 weeks, bone maturation was observed, with the presence of remodeling sites and some areas of well-organized lamellar structures occupying the healing chambers. At both 3 and 12 weeks, the Mp implants demonstrated significantly higher BAFO values relative to ND (p = 0.015 and p = 0.008, respectively). The combination of vertical healing chambers, acid etching, and NTP treatment promoted early vascular infiltration and sustained bone deposition.