RESUMEN
The use of titanium implants is well documented and they have high survival and success rates. However, when used as reduced-diameter implants, the risk of fracture is increased. Narrow diameter implants (NDIs) of titanium-zirconium (Ti-Zr) alloy have recently been developed (Roxolid; Institut Straumann AG). Ti-Zr alloys (two highly biocompatible materials) demonstrate higher tensile strength than commercially pure titanium. The aim of this systematic review was to summarize the existing clinical evidence on dental NDIs made from Ti-Zr. A systematic literature search was performed using the Medline database to find relevant articles on clinical studies published in the English language up to December 2014. Nine clinical studies using Ti-Zr implants were identified. Overall, 607 patients received 922 implants. The mean marginal bone loss was 0.36±0.06mm after 1 year and 0.41±0.09mm after 2 years. The follow-up period ranged from 3 to 36 months. Mean survival and success rates were 98.4% and 97.8% at 1 year after implant placement and 97.7% and 97.3% at 2 years. Narrow diameter Ti-Zr dental implants show survival and success rates comparable to regular diameter titanium implants (>95%) in the short term. Long-term follow-up clinical data are needed to confirm the excellent clinical performance of these implants.
Asunto(s)
Aleaciones Dentales/uso terapéutico , Implantes Dentales , Titanio , Circonio , Aleaciones Dentales/química , Diseño de Prótesis Dental , Humanos , Ensayo de Materiales , Resistencia a la TracciónRESUMEN
The aim of this study was to define the three-dimensional angulation of the pterygomaxillary corridor in which pterygoid implants should ideally be placed. A secondary objective was to study the bone density in the tuberosity area and pterygoid plate. Two hundred and two cone beam computed tomography files of atrophic posterior maxillae were evaluated. Implant placement was guided by the individual anatomy of each patient. The mean implant angulation was 74.19±3.13° in the anteroposterior axis and 81.09±2.65° in the buccopalatal axis, relative to the Frankfort plane. Density in the tuberosity area ranged from 285.8 to 329.1DV units and density in the pterygoid plate area from 602.9 to 661.2DV units, with a 95% confidence interval. The density in the pterygoid area was 139.2% greater than in the tuberosity zone. Implant placement should be guided by the individual anatomy of each patient. Statistically significant differences were found between the tuberosity and pterygoid plate in terms of bone density. Based on the results of this study, an implant of at least 15mm long should be used in order to take advantage of the quantity and quality of the bone in this region.