Peri-Implant Marginal Bone Changes around Dental Implants with Platform-Switched and Platform-Matched Abutments: A Retrospective 5-Year Radiographic Evaluation

Abstract

Preserving the marginal bone level (MBL) is essential for the long-term success of dental implant therapy, and bone remodeling around dental implants is considered to vary with time. Numerous studies comparing the platform-switching (PS) and platform-matching (PM) dental implants have indicated that PS dental implants showed a lesser reduction for the MBL, and the majority of them had a relatively short period. This study aimed to evaluate vertical and horizontal bone defects by using digital periapical radiographs to examine the changes in MBL around PM and PS dental implants over 5 years after functional loading. The vertical MBL (vMBL) was measured from the implant–abutment junction to the first bone-to-implant contact. The horizontal MBL (hMBL) was measured from the implant–abutment junction to the bone crest. All data were presented as means ± standard errors. Paired and independent t-tests with Welch’s correction were used to analyze the data. A total of 61 dental implants in 38 patients after 5 years of functional loading were evaluated. Over time, PS dental implants were more likely to gain bone; by contrast, PM dental implants were more likely to lose bone during the observation time. Changes in vMBL for PS dental implants were significantly less than those for PM dental implants at 1-year (p = 0.045), 3-year (p = 0.021), and 5-year (p = 0.010) loading. Likewise, changes in hMBL for PS dental implants were significantly smaller than in those for PM dental implants at 3-year (p = 0.021) and 5-year (p = 0.006) loading; however, the changes were minimal in both approaches. PS dental implants had a significant increment in the percentage of bone integration, whereas that for PM dental implants dropped over time, with no significance. In PS dental implants that occlude with natural teeth, vertical and horizontal bone gain was observed, and it was significant at 3 years (p = 0.023). A significant horizontal bone gain was observed in the opposing natural teeth at 3-year (p = 0.002) and 5-year loading (p = 0.002). The PS concept appears to preserve more MBL around dental implants by stabilizing the vMBL and hMBL over a 5-year period. A minimal marginal bone change was detected in both concepts. The opposing natural teeth at PS dental implants showed a favorable effect on marginal bone tissues.

Comparison of values of crestal bone loss around dental implants: A comparative study

“…They reported a higher vertical marginal bone loss around dental implants with platform-switched abutments (1.67 ± 0.24 mm) than platform-matched (conventional platform) dental implants (0.88 ± 0.17 mm) in the early healing period. At 1-year and at 3-year loading, platform-switching dental implants were less likely to lose bone (17).…”

Evaluation of stress distribution in and around dental implants using three different implant–abutment interfaces with platform-switched and non-platform-switched abutments: A three-dimensional finite element analysis

“…Clinical studies have also demonstrated that less bone resorption occurs when a smaller diameter abutment is used with the platform switching technique. 20 , 21 …”

“…Clinical studies have also demonstrated that less bone resorption occurs when a smaller diameter abutment is used with the platform switching technique. 20,21 Platform switching causes the inward shifting of the inflammatory cell infiltrate away from the crestal bone, 22 and increases the distance between IAJ and the crestal bone level. Systematic reviews by Atieh et al, 23 Strietzel et al, 24 and Gupta et al 25 stated that significantly less marginal bone loss was seen with platform-switched implants, concluding that platform switching helps preserve crestal bone around implants.…”

The implant loading influence on crestal bone remodelling around hybrid titanium implants: a prospective clinical study

“…In the last decade, it was already defined how the behaviour of bone structures can be predicted in the face of a constant stimulus, which trans-lates into the preservation of bone tissue (5). An ineffective mechanical stimulus can lead to reabsorption due to disuse.…”