Prefabricated zirconium dioxide implant abutments for single‐tooth replacement in the posterior region: evaluation of peri‐implant tissues and superstructures after 12 months of function

Aim: In the present study, prefabricated abutments made of zirconium dioxide Y‐TZP (tetragonal zirconia polycrystals) were inserted into the posterior region under controlled clinical conditions. The aim was to test whether abutments made of zirconium dioxide are suitable for this indication. Investigation parameters included reactions of peri‐implant tissue and the structural integrity of the all‐ceramic superstructures on the implants. Results after 12 months in function are reported in this article. Material and methods: Forty implants of the XiVE^® S plus screw‐type implants (DENTSPLY Friadent) were inserted into the posterior region of 24 patients. After the healing period, the implants were provided with all‐ceramic abutments made of zirconium dioxide Y‐TZP (FRIADENT^® CERCON^® Abutment; DENTSPLY Friadent). All‐ceramic crowns (CERCON^® smart ceramics; DENTSPLY DeguDent) were used as superstructures and cemented using the conventional method. The following parameters were used to document the state of soft tissue: modified plaque index (mPI), sulcus fluid flow rate (SFFR, Periotron; Oraflow Inc), modified sulcus bleeding index (mSBI) and pocket depth (ST). Mesial and distal bone levels were determined on radiographs during the prosthetic treatment and at the 12‐month recall. The Periotest^? (Medizintechnik Gulden) was used to determine implant stability. Results: All implants could be followed up after 12 months in function. In the presence of good oral hygiene (mPI: 0.5), the parameters SFFR (18) and mSBI (0.5) were indicative of stable and healthy soft tissue. ST was highest at the distal points of measurement (2.3 mm) and was generally at a low level. Compared with the baseline situation, proximal bone defects were reduced from ?1.1 to ?1 mm during the 12‐month period of functioning. The mean Periost^? values at the 12‐month recall were ?1.9 in the maxilla and ?3.8 in the mandible. Neither implant loss nor crown fractures occurred. Chipping of parts of the veneering ceramic was registered in four cases (10%). Conclusion: After 12 months of wear, no mechanical failure was registered in any of the all‐ceramic abutments. On clinical investigation, the peri‐implant hard and soft tissues were largely healthy and devoid of inflammation. To cite this article:
Nothdurft F, Pospiech P. Prefabricated zirconium dioxide implant abutments for single‐tooth replacement in the posterior region: evaluation of peri‐implant tissues and superstructures after 12 months of function.
Clin. Oral Impl. Res. 21 , 2010; 857–865.
doi: 10.1111/j.1600‐0501.2009.01899.x     

Peri‐implant soft tissue and bone crest alterations at fixed dental prostheses: a 3‐year prospective study

Objectives: The aim of this 3‐year prospective study involving patients receiving implant‐supported fixed dental prostheses (FDPs) was to longitudinally evaluate soft and hard tissue alterations from the time of implant placement. Material and methods: Sixteen subjects with 18 implant‐supported FDPs on 43 implants were included in the study. Peri‐implant soft and hard tissue assessments were performed at implant placement, 2, 6, 12, 24 and 36 months. Variables describing the peri‐implant soft tissue conditions and topography were assessed by clinical, photographic and study model assessments. Variables of implant position and bone topography were measured in radiographs taken at each examination interval. Multilevel regression models were formulated to identify factors of significance for proximal bone crest alterations and proximal soft tissue height. Results: During the first 6 months after the one‐stage implant placement surgery, the soft tissue margin receded about 0.6 mm at facial implant sites, while a mean increase was observed at tooth‐facing proximal sites (1.1 mm) and no change at inter‐implant sites. Loss in proximal bone crest height was more pronounced at inter‐implant than tooth–implant units at 6 months (0.6 vs. 0.1 mm). Between 6 and 36 months, no further significant soft or hard tissue changes were observed. Multilevel regression analysis revealed that the proximal bone crest level significantly influenced the proximal soft tissue height assessed from the implant/abutment level. Significant predictors for loss in proximal bone crest level over the 3 years were horizontal inter‐unit distance, type of proximal unit (tooth/implant or inter‐implant) and peri‐implant bone‐level change. Conclusions: Soft and hard tissue changes around implant‐supported FDPs took place primarily during the first 6 months after the one‐stage implant installation surgery. The pattern of tissue alterations during the follow‐up differed between tooth–implant and inter‐implant proximal sites. To cite this article:
Chang M, Wennström JL. Peri‐implant soft tissue and bone crest alterations at fixed dental prostheses: a 3‐year prospective study.
Clin. Oral Impl. Res. 21, 2010; 527–534.
doi: 10.1111/j.1600‐0501.2009.01874.x