Performance of a new bone-level tapered two-piece zirconia implant manufactured by injection moulding: A pilot preclinical study in minipig mandibles.

PURPOSE: The aim of this pilot preclinical study was to investigate the performance of a novel double-lead thread, conical bone-level ceramic implant manufactured by injection moulding (test group) in comparison to a well-established cylindrical, soft tissue-level ceramic implant with a single-lead thread manufactured by milling (control group), both sandblasted and acid-etched.

MATERIALS AND

METHODS

A total of 16 implants (n = 8 per group) with a diameter of 3.75 mm (test) and 4.1 mm (control) and a length of 8 mm were placed in the mandibles of four female Göttingen minipigs 12 weeks after tooth extraction. The surface microscopy was evaluated by scanning electron microscopy. Insertion torque values were measured during implant placement. Twelve weeks after implantation, histomorphometric analysis was performed to assess bone-implant contact and first bone-implant contact. An independent samples t test was used to compare the two groups.

RESULTS

The surface of both ceramic implants showed similar roughness and hydrophilicity. No statistically significant difference was reported regarding the insertion torque, bone-implant contact and first bone-implant contact. The mean insertion torque was 64.38 ± 23.21 Ncm for the test group and 64.38 ± 25.42 Ncm for the control group (P = 1.000). The histomorphometric analysis showed mean bone-implant contact of 61.63% ± 13.26% and 70.68% ± 8.63% (P = 0.128) for the test and control group, respectively. The test group showed mean first bone-implant contact of -1.66 ± 0.56 mm for the test group and -1.27 ± 0.89 mm for the control group (P = 0.316).

CONCLUSION

The novel double-lead thread, conical ceramic bone-level implant manufactured by injection moulding showed comparable primary stability and osseointegration to the established single-lead thread, cylindrical ceramic implant.