2.2 Clinical parameters

Periodical clinical examinations assessed before treatment and during follow‐up were recorded. Clinical parameters at baseline and after prosthesis positioning were used as a reference of development of peri‐implant disease.

Based on the suggestion of Mombelli and Lang, and confirmed by the successive EWP consensus workshops published in 2008, 2011, and 2012, peri‐implantitis was defined as “changes in the level of crestal bone, presence of bleeding on probing and/or suppuration; with or without concomitant deepening of the peri‐implant pocket”. So we defined peri‐implantitis using bone level threshold combined with clinical periodontal indexes.

The crestal bone changes were assessed through the radiographic examinations. Periapical radiographs were performed with parallel technique using non‐customized Rinn devices. This technique avoids projective deformation of the image by placing the detector inside the oral cavity with direction parallel to the tooth axis and the center radius of the x‐ray beam perpendicular to the tooth and film. This orientation minimizes geometric distortion and shows tooth‐implant and bone support in their true anatomic relationship.

These data combined with crestal bone changes were only used to make diagnosis of peri‐implantitis.