Mechanical Behaviour and Primary Stability of a Self-Condensing Implant: A Laboratory Critical Simulation of a Severe Maxillary Atrophy on Polyurethane Lamina

Abstract

Background: Posterior maxillary atrophies could emerge after the loss of teeth, trauma, infections, or lesions that often require regenerative approaches. In these critical conditions, the achievement of implant primary stability represents a clinical challenge in the operative practice. Therefore, a two-stage approach is often preferred with a delay of the rehabilitation time and a consistent increasing of the biological and the operative costs. The aim of this study was to evaluate the mechanical behaviour of a self-condenser implant compared to a standard implant in a critical simulation on different thicknesses and densities of polyurethane lamina. Materials and methods: A total of two implant models were tested: a self-condensing device (test) and a standard implant (control). The study evaluated the insertion torque and the pull-out strength values of the test and control implants inserted in different sizes (1, 2, and 3 mm) and density polyurethane lamina (10, 20, and 30 pcf) for a total of 320 experimental sites. Results: In total, 320 experimental sites were produced in the polyurethane samples. A statistically significant difference of insertion and pull-out torque values between the test and control Implants was found in the different bone densities (p < 0.05). The insertion and pull-out torque values were always higher for the test implants in all experimental conditions. In all bone densities, the insertion torque values were higher than the pull-out torque values. The self-condenser dental implant design evaluated in this in vitro study showed a high level of stability in all experimental conditions. Conclusions: The test implant could represent a useful tool for a one-stage surgical approach in the presence of limited residual native bone as an alternative to a delayed technique.

Clinical and Radiological Evaluation of a Self-Condensing Bone Implant in One-Stage Sinus Augmentation: A 3-Year Follow-Up Retrospective Study

“…On these bases, the objective of the present retrospective study was to evaluate the 3-year follow-up clinical and radiographic results of the use of an innovative reverse troncoconical implant design [18], which could allow to obtain at the same time (onestage approach) a maxillary sinus augmentation procedure through transcrestal or lateral approaches and the implant insertion, even in challenging scenarios, such as with bone heights close to 2 mm. All sites included in this study were classified as type IV, according to Lekholm & Zarb [36].…”

“…Furthermore, the IT value is a mechanical parameter that is mainly influenced by the surgical procedure, the implant design, and the bone quality at the implant site [41]. Considering that all sites were characterized by a low quality of the bone, the good primary stability of these implants was a direct consequence of the Sinus-Plant implant design [18] that led to the osseodensification of the bone during the insertion procedure protocol [27,28]. In addition to the use of this type of implants, the one-stage approach allowed to stabilize the implant up to bone heights close to 2 mm, reducing the morbidity and giving the main advantage of reducing the total time for the final resolution of the case.…”

“…Briefly, these implants were characterized by: a tronco-conical shape macromorphology; a titanium lapping surface at the implant rounded apex, able to preserve the Schneiderian membrane integrity; a thread design with a narrow inter-thread distance of 0.4 mm, limiting stress and promoting progressive bone expansion and osseodensification; a Titanium Pull Spray Superficial (TPSS) implant surface (Figure 1). Furthermore, the conometrical prosthetic joint with a switching platform [21,22] helps limiting the marginal bone level alteration and offers a better sealing to reduce bacterial colonization in respect to other connections [18,23].…”

“…a narrow inter-thread distance of 0.4 mm, limiting stress and promoting progressive bone expansion and osseodensification; a Titanium Pull Spray Superficial (TPSS) implant surface (Figure 1). Furthermore, the conometrical prosthetic joint with a switching platform [21,22] helps limiting the marginal bone level alteration and offers a better sealing to reduce bacterial colonization in respect to other connections [18,23].…”

“…Moreover, a one-stage procedure is preferred since a high primary stability and a time-saving in implant placement can be ensured. Recently, a novel self-condensing implant design (Sinus-Plant, Oralplant Suisse, Mendrisio, Switzerland) has been proposed to improve the primary stability of dental implants inserted in the posterior maxilla with a limited residual native bone height [18]. As for other similar implants, this particular tronco-conical morphology allows an optimal bone preservation by creating a compact layer of bone along the surface of the osteotomy and providing a conical coupling between the implant and the bone [19,20].…”