Bone Spreader Technique: A Preliminary 3-Year Study
The purpose of this study was to observe the clinical outcome of bone spreading and standardized dilation of horizontally resorbed bone during immediate implant placement using a “screw-type” configuration of expansion and threadformers. Fifty-three patients were included in this study, and 41 edentulous areas in anterior and posterior maxillas were treated. Sixty-eight implants were placed using an insertion torque of at least 40 Ncm. Abutments were delivered 4 to 6 months after implant placement. The overall failure percentage was 4.41% (3 failures). A retrieved analysis of 1 implant removed at 3 years after placement demonstrated bone resorption down to the level of the third thread. The bone spreader technique is different from Summers' osteotome, both in clinical use and in armamentarium. The main advantage of the crest-expanding technique is that it is a less invasive procedure; the facial wall expands after the medullary bone is compressed against the cortical wall. Within the limits of this preliminary study, the cumulative survival rate for this method of implant placement is 95.58% at 3 years. This study confirms that a bone spreader used in the maxilla shows an unusually low failure rate after 3 years.Abstract

Figure 1. Buccal view of missing incisive. The full-thickness flap was raised and showed bone concavity on the buccal bone. Figure 2. The surgical acrylic template in place to indicate the optimal direction of the implant. Figure 3. Initial threadformer of 2.7 mm diameter is gently screwing into the bone cavity. Figure 4. Widening of the implant cavity, buccal cone condensation. Figure 5. The implant was inserted at 40 Ncm. Figure 6. Prosthetic crowns.
Contributor Notes
professor in the Department of Dental Materials and Prosthodontics, and Francisley Avila Souza, DDS, MSc, postgraduate student of oral and maxillofacial surgery, Department of Clinical and Surgery, are at State University of São Paulo (UNESP) São José dos Campos, São Paulo, Brazil. Address correspondence to Dr Nishioka at Department of Dental Materials and Prosthodontics, State University of São Paulo São José dos Campos–UNESP, Av. Francisco José Longo 777, São Dimas, São José dos Campos, São Paulo–Brazil, Cep: 12245‐000. (e‐mail: nishioka@fosjc.unesp.br)