Five Degree Internal Conical Connection and Marginal Bone Stability around Subcrestal Implants: A Retrospective Analysis

Abstract

Background: There is limited information on the effect of the connection between subcrestally placed implants and abutments on marginal bone levels. The aim of the present retrospective study was to evaluate marginal bone levels after definitive prosthesis delivery around implants with an internal 5° conical connection placed in a subcrestal position. Materials and methods: Patients treated with fixed prostheses supported by implants placed at a subcrestal level between 2012 and 2018 were recalled for a follow-up examination. All implants had 5° internal conical connection with platform switching. Radiographic marginal bone level (MBL) was measured. MBL change between prosthetic delivery (t0) and follow-up examination (t1) was calculated. A multiple regression model was performed to identify the most significant predictors on MBL change. Results: Ninety-three patients and 410 implants, with a mean follow-up of 2.72 ± 1.31 years, were examined. Mean MBL was −1.09 ± 0.65 mm and −1.00 ± 0.37 mm at t0 and t1, respectively, with a mean bone remodeling of 0.09 ± 0.68 mm. An implant’s vertical position in relation to the bone crest, the year of follow up and the presence of type-2 controlled diabetes were demonstrated to be influencing factors for MBL modifications. Conclusions: Subcrestally placed implants with platform switching and internal conical connection maintained stable bone levels over a mean follow-up of more than 2 years. How a tight internal conical connection between abutment and implant may contribute to this clinical evidence should be more deeply investigated. MBL variations seem to be mostly influenced by an implant’s vertical position and presence of type-2 controlled diabetes.

Marginal Bone Maintenance and Different Prosthetic Emergence Angles: A 3-Year Retrospective Study

“…In fact, that kind of additional evaluation should require invasive 3D radiographs; for ethical reasons, such an approach was not possible to be achieved. In daily clinical practice, and particularly in the anterior area, it is now recognized that the vestibular-palatal position of the implant must be more palatal than the line that joins the center of the crowns of the adjacent teeth to allow an adequate thickness of vestibular bone [ 6 ]. This implant positioning may provide for an accentuated emergence angle if compared to the adjacent natural teeth.…”

“…For each implant, a two-stage surgical technique was chosen. Implants were placed 1 to 2 mm below the crestal level [ 6 ], as recommended by the manufacturer, according to the scalloping of the bone crest.…”

Association between Peri-Implant Soft Tissue Health and Different Prosthetic Emergence Angles in Esthetic Areas: Digital Evaluation after 3 Years’ Function

“…As previously described by Lops et al [ 10 ] a submerged healing technique was chosen for the implants that were placed (Anyridge, Megagen Implants, Seoul, Korea) 1 to 2 mm below the crestal level [ 15 ], as recommended by the manufacturer.…”

Effect of Different Dental Implant Prosthetic Joints on Marginal Bone Loss: Emerging Findings from a Bayesian Network Meta-Analysis (NMA) and Systematic Review

“…A total of eight different prosthetic joint connections have been considered: internal hexagonal joint 1 mm below the bone level position [19][20][21][22][23][24][25][26][27], internal hexagonal joint at bone level position [19], external hexagonal joint at bone level position [23,25,26,[28][29][30][31], Internal conical prosthetic joint with index [19,22,27,28,[31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46], cone morse 1 mm below the bone level position [23][24][25][26]30,[47][48][49], cone morse at the bone level position [49], 1). A total of eight different prosthetic joint connections have been considered: interna...…”