Evaluation of guided dynamic surgery for single implants in the cosmetic dentistry sector, programmed by means of a digitally-guided prosthetic workflow: follow-up after 1 year

Oral implantology makes use of osseointegrated implants used in support of a fixed or removable prosthetic rehabilitation. Modern oral implantology and the study of the osseointegration process was initiated in the 1960s by Swedish researcher Per-Ingvar Brånemark and his collaborators. Professor Brånemark first confronted this particular phenomenon in 1952 during an in vivo rabbit trial with the aim of studying the healing processes of bone fractures. At the conclusion of the experiments, Brånemark noted that it was impossible to remove the metal structure from its housing and this phenomenon was termed osseointegration. The use of osseointegrated implants, originally reserved for the treatment of complete edentulism, was later extended to partial and single edentulism. Over the years, several definitions of osseointegration have been proposed; Albrektsson1 in 1981, defines osseointegration as 'direct contact between titanium implant and living bone without interposition of soft tissue'. Subsequently, Brånemark2.3 defines it as the 'structural and functional connection between living bone structure and the surface of an implant'. Finally, Schroeder histologically demonstrated the actual contact between the surface of the titanium implant and the surrounding bone tissue, calling it 'functional ankylosis'. Albrektsson1 in 1986 outlined the so-called critical variables of osseointegration and modifiable factors affecting osseointegration: implant material, design (macrostructure), finish (microstructure), bone quality, surgical technique and loading conditions. Furthermore, in 1986 he defined the criteria for successful osseointegrated implants: - immobility of individual non-prosthetic implants - absence of peri-implant radiolucency - peri-implant bone resorption <0.2 mm/year after the first year of prosthetic loading - absence of persistent and irreversible symptoms such as pain, infections, invasion of the mandibular canal, paresthesia and neuropathies - success rate > 85% 5 years after placement and 80% after 10 years. These success criteria can still be considered valid even though other parameters for evaluating implant success have subsequently been proposed. The introduction of modified implant surfaces (sandblasted, etched, etc.) has enabled an improvement in the quality and quantity of the osseointegration process while also reducing healing time. In 2000 Misch5 then changed the success rates to 90% after 5 years and 85% after 10 years. Shifting the focus to the success of the entire rehabilitation, Misch6 in 2005, then stated that the survival rate of an implant prosthetic rehabilitation is about 90 % after 10 years.