Evaluation of contiguous implants with cement-retained implant-abutment connections. A minipig study

• Main Authors: Raquel Rezende Martins de Barros, Arthur Belém Novaes Junior, Vula Papalexiou, Sônia Mara Luczyszyn, Stylianos Nicolas Papalexiou Neto, Cassiana Maria Garcez Ramos, Adriana Luisa Gonçalves De Almeida, Adriano Piattelli, Bartolomeo Assenza
• Format: Article
• Language: English
• Published: Ariesdue 2014-03-01
• Series: Journal of Osseointegration
• Subjects: abutment; Bone resorption; Dental implant; Papillae formation; Abutment
• Online Access: http://www.journalofosseointegration.eu/wp-content/uploads/2014/05/JO_14_6_1_1.pdf
• ISSN: 2036-413X; 2036-4121

Aim: The presence of a microgap at the implant-abutment interface may permit bacterial contamination and lead to bone resorption, interfering with papillae formation. The present study evaluated adjacent implants with cement-retained abutments as an option to control such deleterious effects. Materials and methods Seven minipigs had their bilateral mandibular premolars previously extracted. After 8 weeks, four implants were installed in each hemi-mandible of each animal. The adjacent implants were randomly inserted on one side at the crestal bone level and on the other, 1.5 mm subcrestally. Immediately, a non-submerged healing and functional loading were provided with the abutments cementation and prostheses installation. Clinical examination and histomorphometry served to analyze the implant success. Results A total of 52 implants were evaluated at the end of the study. The subcrestal group achieved statistical better results when compared to the crestal group, clinically in papillae formation (1.97 x 1.57 mm) and histomorphometrically in crestal bone remodeling (1.17 x 1.63 mm), bone density (52.39 x 45.22%) and bone-implant contact (54.13 x 42.46%). Conclusion The subcrestal placement of cement-retained abutment implants showed better indexes of osseointegration and also improved papillae formation and crestal bone remodeling at the interimplant area after immediate loading, making them a promising option for the treatment of esthetic regions.