Antonio Liñares1, Raul Verdeja2, Benjamin Pippenger3, Fernando Muñoz4, Mónica López-Peña4, Juan Blanco5. 1. Periodontology Unit, School of Medicine and Dentistry, University of Santiago de Compostela, Rúa San Francisco s/n 15782, Santiago de Compostela, Spain. antonio.linares@usc.es. 2. Department of Surgery, Service of Maxillofacial and Oral Surgery, University Hospital and Faculty of Medicine, Geneva, Switzerland. 3. Preclinical & Translational Research, Institut Straumann, Basel, Switzerland. 4. Department of Veterinary Clinical Sciences, Universidade de Santiago de Compostela, Lugo, Spain. 5. Periodontology Unit, School of Medicine and Dentistry, University of Santiago de Compostela, Rúa San Francisco s/n 15782, Santiago de Compostela, Spain.
Abstract
OBJECTIVES: To develop a new preclinical model to study early implant loss, where local infection conditions would impair the implant osseointegration. MATERIALS AND METHODS: Forty-eight smooth, 2.9-mm diameter experimental implants were placed in the mandible of 8 beagle dogs (3 in each side). In half of the animals (test group, n = 24 implants), the implants received ligatures around the implant-abutment connection. In the other half, no ligatures were placed (control group, n = 24 implants). Four weeks later, implants were extracted in a flapless approach and standard 3.3-mm diameter SLActive implants were placed into the same osteotomy site without any further drilling. Eight weeks after the second implantation, animals were sacrificed and analyzed in terms of implant survival. RESULTS: After 8 weeks of healing, 4 implants were lost in the control group and 14 in the test group. This corresponded to a 17.4% of early implant loss in the control group and 58.3% in the test. Most of the early failures occurred within the first 5 weeks of healing. CONCLUSIONS: Implants placed in a pre-contaminated site present higher early loss than those placed in a non-contaminated site. This study represents a valid and robust preclinical model to study mechanisms and reduction of early implant loss as new technologies become available. CLINICAL RELEVANCE: Scientific rationale for the study: There is lack of animal models to study early implant loss. Thus, a proposal of a new model is presented. With the validation of this model, new technologies can be implemented to prevent early implant loss.
OBJECTIVES: To develop a new preclinical model to study early implant loss, where local infection conditions would impair the implant osseointegration. MATERIALS AND METHODS: Forty-eight smooth, 2.9-mm diameter experimental implants were placed in the mandible of 8 beagle dogs (3 in each side). In half of the animals (test group, n = 24 implants), the implants received ligatures around the implant-abutment connection. In the other half, no ligatures were placed (control group, n = 24 implants). Four weeks later, implants were extracted in a flapless approach and standard 3.3-mm diameter SLActive implants were placed into the same osteotomy site without any further drilling. Eight weeks after the second implantation, animals were sacrificed and analyzed in terms of implant survival. RESULTS: After 8 weeks of healing, 4 implants were lost in the control group and 14 in the test group. This corresponded to a 17.4% of early implant loss in the control group and 58.3% in the test. Most of the early failures occurred within the first 5 weeks of healing. CONCLUSIONS: Implants placed in a pre-contaminated site present higher early loss than those placed in a non-contaminated site. This study represents a valid and robust preclinical model to study mechanisms and reduction of early implant loss as new technologies become available. CLINICAL RELEVANCE: Scientific rationale for the study: There is lack of animal models to study early implant loss. Thus, a proposal of a new model is presented. With the validation of this model, new technologies can be implemented to prevent early implant loss.