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Purpose: To histometrically compare the osseointegration and crestal bone healing of a novel tapered, self‐cutting tissue‐level test implant with a standard tissue‐level control implant in a submerged healing regimen. Materials and Methods: In a mandibular minipig model, implants were inserted and evaluated histometrically after a healing period of 3, 6, and 12 weeks. The primary outcome was the evaluation of bone‐to‐implant contact (BIC) and secondary outcomes were primary stability as per insertion torque and first BIC (fBIC). Outcomes for the test and control implants were compared using Wilcoxon signed‐rank tests and mixed linear regression models. Results: Insertion torque values were significantly higher for the test (50.0 ± 26.4 Ncm) compared to the control implants (35.2 ± 19.7 Ncm, p =.0071). BIC values of test implants were non‐inferior to those of control implants over the investigated study period. After 12 weeks, the corresponding values measured were 81.62 ± 11.12% and 90.41 ± 4.81% (p =.1763) for test and control implants, respectively. Similarly, no statistical difference was found for fBIC values, except for the 12 weeks outcome that showed statistically lower values for the test (−675.58 ± 590.88 μm) compared to control implants (−182.75 ± 197.40 μm, p =.0068). Conclusions: Novel self‐cutting tissue‐level implants demonstrated noninferior osseointegration and crestal bone height maintenance to the tissue‐level implants. Histometric outcomes between both implants demonstrated test implants were statistically noninferior to control implants, despite substantial differences in the bone engagement mechanism and resulting differences in insertion torque and qualitative bone healing patterns. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present study was to compare a novel tapered, double‐threaded self‐tapping tissue‐Level design implant (TLC) to a well‐established parallel walled tissue‐level (TL) implant in terms of primary and secondary stability over time. Materials and Methods: Test TLC (n = 10/per timepoint) and control TL (n = 10/per timepoint) implants were placed in the mandible of minipigs and left for submerged healing for 3, 6, and 12 weeks. Maximum insertion torque and implant stability quotient (ISQ) were measured for each implant at placement. Osseointegration and cortical bone maintenance were histologically evaluated by measuring total bone‐to‐implant contact (BIC) and first bone‐to‐implant contact (fBIC). Results: A significantly higher maximum insertion torque was measured for the test implant TLC compared to the control TL implant (57.83 ± 24.73 Ncm and 22.62 ± 23.16 Ncm, respectively; p <.001). The mean ISQ values were comparable between the two implant types (75.00 ± 6.70 for TL compared to 75.40 ± 3.20 for TLC, p =.988). BIC was comparable between both implant types at each of the evaluated time points. The fBIC was found to be significantly more coronal at 12 weeks for the TLC implant compared to the TL implant (0.31 ± 0.83 mm for TLC compared to −0.22 ± 0.85 for TL, p =.027). Conclusion: The novel tapered tissue level design implant showed improved primary stability and an overall improved crestal bone height maintenance compared to the parallel walled design at 12 weeks. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the impact of a Ti‐Sr‐O technology, applied to either a turned surface or an SLA surface, on the mechanical robustness of osseointegration, benchmarked against the SLActive surface. Material and Methods: Ti discs (6.25‐mm‐diameter and 2‐mm‐thick) with three different surfaces were inserted on the proximal‐anterior part of the tibial plateau of adult Swedish loop rabbits: (I) turned surface modified with Ti‐Sr‐O (turned + Ti‐Sr‐O), (II) SLA surface modified with Ti‐Sr‐O (SLA + Ti‐Sr‐O), and (III) SLActive surface (SLActive). Following a healing period of 2 weeks and 4 weeks, the pull‐out (PO) force needed to detach the discs from the bone was assessed, as a surrogate of osseointegration. Results: The SLActive surface exhibited statistically significant higher median PO forces, compared with the SLA + Ti‐Sr‐O surfaces at both 2‐ and 4 weeks post‐op (p >.05). In this study, no single turned + Ti‐Sr‐O surface disk was integrated. Conclusions: The tested Ti‐Sr‐O technology failed to enhance osseointegration; however, this finding may be related to the inappropriateness of the rabbit tibia plateau model for assessing third‐generation implant surface technologies, due to the limited diffusion and clearance at the disk‐bone interface. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate and compare bone growth and implant integration in circumferential defects with two commercially available bone substitutes (demineralized bovine bone mineral [DBBM]). Materials and Methods: Circumferential defects were created in the mandibles of minipigs (n = 10), and Bone Level Tapered implants (Straumann Roxolid with SLActive surface) were placed. The defects (4-mm-deep circumferential defect, 2 mm around each implant) were augmented with either sintered bovine bone mineral (test, cerabone) or natural bovine bone mineral (control, Bio-Oss). Bone formation and tissue composition in augmented sites were histomorphometrically assessed after 8 and 12 weeks of healing time (n = 5 each), respectively, in terms of the percentage of area of newly formed bone to total area, bone-to-implant contact (BIC), and crestal bone height relative to the implant shoulder (first bone-to-implant contact [fBIC]). Results: Bone formation in all defect sites was adequate and equivalent for both groups at individual healing time points. The amount of residual graft material was comparable in both groups after 8 and 12 weeks, with no significant resorption in either group. The mean newly formed bone area in the test group amounted to 46.7% ± 5.1% and 48.7% ± 4.0% after 8 and 12 weeks vs 47.0% ± 4.8% and 47.8% ± 7.3% in the control group, respectively. BIC and fBIC as individually assessed for the lingual and buccal aspects were comparable at both healing time points without any statistically significant differences between the groups. A slightly greater variability of fBIC was observed within the test group. Conclusion: The results of this study indicate that test and control materials both represent viable bovine bone graft material that equivalently support the formation of new and stable bone volume specifically when used for simultaneous augmentation around implants. [ABSTRACT FROM AUTHOR]

Aim: To histologically evaluate the influence of (1) loading and (2) grafting on osseointegration and peri‐implant soft‐tissue healing at immediately placed, self‐cutting progressive tissue‐level implants (TLX) in a minipig model. Materials and Methods: TLX implants (n = 56) were immediately placed following the extraction of the mandibular first and second premolars, bilaterally, in a total of n = 14 minipigs. In each animal, the implant sites were allocated to the following four groups: (1) unloaded with simultaneous grafting using a bovine bone mineral; (2) unloaded without grafting; (3) loaded with simultaneous grafting; and (4) loaded without grafting. Histomorphometric assessments at 4 and 12 weeks (n = 7 animals each) included primary (i.e., bone‐to‐implant contact [BIC]) and secondary outcome measures (e.g., first BIC [fBIC], junctional epithelium length [JE], connective tissue contact length [CTC], biological width [BW = JE + CTC]). Results: At 4 weeks, mean BIC values ranged from 74.5 ± 11.6% in Group 2 to 83.8 ± 13.3% in Group 1, and, at 12 weeks, from 75.5% ± 7.9% in Group 2 to 79.9 ± 8.6% in Group 1. Multivariate linear mixed regression did not reveal any associations between BIC and implant loading or grafting at 4 and 12 weeks. At 12 weeks, significantly higher fBIC values were noted in Group 2 when compared with Group 1. All groups showed comparable JE, CTC, and BW values. Conclusions: Implant loading and grafting had no major effects on osseointegration and peri‐implant soft tissue healing at TLX implants. [ABSTRACT FROM AUTHOR]

Purpose: Only limited information on the effect of implant surface hydrophilicity in conjunction with simultaneous bone augmentation is available. In this study, new bone growth around implants with a superhydrophilic modSLA (SLActive) and hydrophobic SLA (SLA) surface were compared in circumferential defects when grafted in conjunction with mineralized cancellous bone allograft (MCBA, maxgraft) or sintered bovine bone mineral (SBBM, cerabone). Materials and Methods: The osseointegration and bone formation in circumferential defects in minipig mandibles around Straumann Roxolid, Ø 3.3 mm, length 8 mm, either SLA or SLActive, were evaluated. Following implant placement, the 2-mm circumferential defects around the implants were filled with MCBA or SBBM. The distance from the implant shoulder to first bone-to-implant contact (f-BIC), percentage of bone-to-implant contact (BIC), and bone aggregate percentage (amount of new bone and remaining graft) within the defect area were evaluated after 8 weeks of healing. Results: In the SBBM group, lingual f-BIC and buccal BIC were significantly lower for SLA (mean --0.404 ± 0.579 mm for modSLA vs --1.191 ± 0.814 mm for SLA, P = .021, and mean 62.61% ± 9.49% for modSLA vs 34.67% ± 24.41% for SLA, P = .047, respectively). Bone aggregate percentage was significantly higher for modSLA vs SLA implants in SBBM (77.84% ± 6.93% vs 64.49% ± 13.12%, P = .045). The differences between implant surfaces in MCBA showed a similar trend but were less pronounced than in the SBBM group and did not reach a statistically significant level. Conclusion: The results suggest that implants with a superhydrophilic modSLA surface are more conducive to faster osseointegration even in conjunction with simultaneous bone grafting procedures. [ABSTRACT FROM AUTHOR]

Purpose: The placement of immediate implants has become a routine treatment modality for the replacement of missing teeth. The aim of the present study was to evaluate dimensional changes of hard tissues following tooth extraction, implant bed preparation, and the subsequent integration of titanium implants placed immediately or following an 8-week healing period. Materials and Methods: All mandibular premolars were extracted and used as experimental sites in five beagle dogs. The left quadrant was used to compare the healing of alveolar bone following regular tooth extraction or surgical implant bed preparation. The right quadrant was used to compare immediate with delayed implant placement (3.3 mm, Bone Level SLActive, Roxolid, Straumann) after an 8-week healing period. All samples were assessed histologically for new bone area/total area (BATA), bone-to-implant contact (BIC), and bone height changes from the buccal and lingual midlines. Results: Implant bed preparation led to significantly lower BATA values and bone height loss compared with regular extraction sockets (–2.46 mm vs –1.44 mm, respectively; P = .0007). Placement of immediate implants demonstrated buccal and lingual bone height loss of 1.51 mm and 0.91 mm, respectively, whereas only 0.12 mm and 0.12 mm of bone height loss was observed during delayed implant placement. A significantly higher BIC was observed for implants placed immediately compared with delayed placement (52% vs 35%, P < .05). Conclusion: Implant bed preparation further increased dimensional changes when compared with routine extraction sockets. Although immediate implant placement produced better BIC than did delayed placement, a significantly higher bone height loss at both the buccal and lingual midlines was reported. Further investigation is underway to minimize dimensional changes following immediate implant placement. [ABSTRACT FROM AUTHOR]

Purpose: Tapered implants are thought to result in equivalent long-term stability and marginal peri-implant bone height in comparison to cylindrical implants. The goal of this study was to compare the primary stability and osseointegration of a novel bone-level tapered-wall implant to a control bone-level cylindrical implant with exactly the same surface characteristics, in a direct side-by-side comparison in an animal model. Materials and Methods: Mandibular premolars and first molars were extracted in 11 Göttingen minipigs, and healing was allowed for 3 months. Six implants were placed with a 4-week surgical lag time between hemimandibles (three per side), and either immediately loaded (first implantation time point) or submerged (second implantation time point). Eight-mm-long × 4.1-mm-diameter titanium screw-type bone-level implants with tapered (two per side) and cylindrical bodies (one per side) were used (Institut Straumann); insertion torque and implant stability were measured, and the soft tissue was closed. Standardized radiographs were taken at implant placement and at sacrifice. Following a healing period of 1 month from the last surgical intervention (8 weeks total healing time for loaded implants; 4 weeks total healing time for nonloaded implants), the animals were sacrificed and mandibular blocks were harvested for nondecalcified histologic and histomorphometric analysis. Results: All implants were integrated radiographically and osseointegrated histologically. Maximum insertion torque measurements and implant stability quotient values showed no significant difference between tapered and cylindrical implants. Histomorphometric analysis also resulted in comparable bone-to-implant contact values between the implant types and similarly limited marginal periimplant bone resorption; no significant differences were observed regarding all the evaluated parameters between the groups, regardless of the loading regime. Conclusion: In a direct side-by-side comparison, in an intraoral minipig model, a novel bone-level tapered screw implant with an SLActive surface showed comparable clinical and histologic outcomes to a parallel-walled bone-level screw implant with an SLActive surface. [ABSTRACT FROM AUTHOR]