Effects of condensation and compressive strain on implant primary stability

Aims Surgeons and most engineers believe that bone compaction improves implant primary stability without causing undue damage to the bone itself. In this study, we developed a murine distal femoral implant model and tested this dogma. Methods Each mouse received two femoral implants, one placed into a site prepared by drilling and the other into the contralateral site prepared by drilling followed by stepwise condensation. Results Condensation significantly increased peri-implant bone density but it also produced higher strains at the interface between the bone and implant, which led to significantly more bone microdamage. Despite increased peri-implant bone density, condensation did not improve implant primary stability as measured by an in vivo lateral stability test. Ultimately, the condensed bone underwent resorption, which delayed the onset of new bone formation around the implant. Conclusion Collectively, these multiscale analyses demonstrate that condensation does not positively contribute to implant stability or to new peri-implant bone formation. Cite this article: Bone Joint Res. 2020;9(2):60–70.

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Can Some Physical Therapy and Manual Techniques Generate Potentially Osteogenic Levels of Strain Within Mammalian Bone?

Physical Therapy ◽

10.1093/ptj/79.10.931 ◽

1999 ◽

Vol 79 (10) ◽

pp. 931-938

Author(s):

Andrew W Wilson ◽

Helen MS Davies ◽

Glenn A Edwards ◽

Brian L Grills

Keyword(s):

Physical Therapy ◽

Bone Formation ◽

Ex Vivo ◽

Compressive Strain ◽

Animal Experiments ◽

New Bone Formation ◽

Joint Injuries ◽

Mechanical Devices ◽

Almost All

Abstract Background and Purpose. Although physical therapy techniques are used to alleviate pain and stiffness in joint injuries, whether these methods are capable of affecting bone is unknown. For example, can these techniques potentially influence bone formation or resorption? To begin exploring this possibility, this study investigated the ability of 4 manual techniques to generate levels of compressive strains that presumably can stimulate bone metabolism. Subjects. Six 3,4 metacarpals from three 3-year-old Merino ewes were used. Methods. A rosette strain gauge was implanted onto the dorsomedial cortex of each ovine 3,4 metacarpal. Four different manual procedures were applied on 2 occasions on each metacarpal in vivo and ex vivo. Mean peak principal compressive strains were calculated for each technique. Results. Levered bending produced greater mean peak compressive strains than almost all other manual procedures tested in vivo or ex vivo. Conclusion and Discussion. Manual levered bending created levels of compressive strain similar in magnitude to those created by mechanical devices used in previous animal experiments to induce new bone formation (osteogenesis). This animal model appears to be suitable for investigating the effects of manually applied procedures on bone and may establish whether manual techniques can stimulate bone formation.

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Mechanical and Biological Advantages of a Tri-Oval Implant Design

Journal of Clinical Medicine ◽

10.3390/jcm8040427 ◽

2019 ◽

Vol 8 (4) ◽

pp. 427 ◽

Cited By ~ 1

Author(s):

Xing Yin ◽

Jingtao Li ◽

Waldemar Hoffmann ◽

Angelines Gasser ◽

John Brunski ◽

...

Keyword(s):

Bone Resorption ◽

High Strain ◽

Compressive Strain ◽

Primary Stability ◽

Implant Design ◽

Insertion Torque ◽

Implant Survival ◽

Implant Stability ◽

Over Time

Of all geometric shapes, a tri-oval one may be the strongest because of its capacity to bear large loads with neither rotation nor deformation. Here, we modified the external shape of a dental implant from circular to tri-oval, aiming to create a combination of high strain and low strain peri-implant environment that would ensure both primary implant stability and rapid osseointegration, respectively. Using in vivo mouse models, we tested the effects of this geometric alteration on implant survival and osseointegration over time. The maxima regions of tri-oval implants provided superior primary stability without increasing insertion torque. The minima regions of tri-oval implants presented low compressive strain and significantly less osteocyte apoptosis, which led to minimal bone resorption compared to the round implants. The rate of new bone accrual was also faster around the tri-oval implants. We further subjected both round and tri-oval implants to occlusal loading immediately after placement. In contrast to the round implants that exhibited a significant dip in stability that eventually led to their failure, the tri-oval implants maintained their stability throughout the osseointegration period. Collectively, these multiscale biomechanical analyses demonstrated the superior in vivo performance of the tri-oval implant design.

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Correlation between Primary, Secondary Stability, Bone Density, Percentage of Vital Bone Formation and Implant Size

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18136994 ◽

2021 ◽

Vol 18 (13) ◽

pp. 6994

Author(s):

Vasilena Ivanova ◽

Ivan Chenchev ◽

Stefan Zlatev ◽

Eitan Mijiritsky

Keyword(s):

Bone Density ◽

Bone Formation ◽

Linear Correlation ◽

Bone Biopsy ◽

Primary Stability ◽

Implant Stability ◽

Socket Preservation ◽

Implant Placement ◽

Significant Difference ◽

Secondary Stability

Background: This study aims to evaluate whether there is a correlation between implant stability, bone density, vital bone formation and implant diameter and length. Methods: Ninety patients were enrolled in this study. They underwent a socket preservation procedure with allograft or PRF and after 4 months, a total of 90 implants were placed. CBCT scans were assigned prior to implant placement in order to assess the bone density. During the surgical re-entry, a bone biopsy was harvested with a trephine drill. Immediately after implant insertion, the primary stability was measured. The secondary stability was measured 4 months after implant placement. Results: Primary stability showed a significant positive linear correlation with bone density (r = 0.471, p < 0.001) as well as with percentage of new bone formation (r = 0.567, p < 0.001). An average significant association of secondary stability with bone density (rs = 0.498, p < 0.001) and percentage of newly formed bone (r = 0.477, p < 0.001) was revealed. The mean values of primary stability in all three implant sizes, regarding the diameter of the implants, were similar (narrow 67.75; standard 66.78; wide 71.21) with no significant difference (p = 0.262). The same tendency was observed for secondary stability (narrow 73.83; standard 75.25; wide 74.93), with no significant difference (p = 0.277). Conclusions: The study revealed a high correlation between primary and secondary implant stability, and bone density, as well as with the percentage of vital bone formation. Implant length and diameter revealed no linear correlation with the implant stability.

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In Vivo Study for Clinical Application of Dental Stem Cell Therapy Incorporated with Dental Titanium Implants

Materials ◽

10.3390/ma14020381 ◽

2021 ◽

Vol 14 (2) ◽

pp. 381

Author(s):

Hyunmin Choi ◽

Kyu-Hyung Park ◽

Narae Jung ◽

June-Sung Shim ◽

Hong-Seok Moon ◽

...

Keyword(s):

Stem Cells ◽

Bone Formation ◽

Alveolar Bone ◽

Human Mesenchymal Stem Cells ◽

Titanium Implants ◽

Osteogenic Potential ◽

Induction Medium ◽

Radiographic Analysis ◽

New Bone Formation

The aim of this study was to investigate the behavior of dental-derived human mesenchymal stem cells (d-hMSCs) in response to differently surface-treated implants and to evaluate the effect of d-hMSCs on local osteogenesis around an implant in vivo. d-hMSCs derived from alveolar bone were established and cultured on machined, sandblasted and acid-etched (SLA)-treated titanium discs with and without osteogenic induction medium. Their morphological and osteogenic potential was assessed by scanning electron microscopy (SEM) and real-time polymerase chain reaction (RT-PCR) via mixing of 5 × 106 of d-hMSCs with 1 mL of Metrigel and 20 μL of gel-cell mixture, which was dispensed into the defect followed by the placement of customized mini-implants (machined, SLA-treated implants) in New Zealand white rabbits. Following healing periods of 2 weeks and 12 weeks, the obtained samples in each group were analyzed radiographically, histomorphometrically and immunohistochemically. The quantitative change in osteogenic differentiation of d-hMSCs was identified according to the type of surface treatment. Radiographic analysis revealed that an increase in new bone formation was statistically significant in the d-hMSCs group. Histomorphometric analysis was in accordance with radiographic analysis, showing the significantly increased new bone formation in the d-hMSCs group regardless of time of sacrifice. Human nuclei A was identified near the area where d-hMSCs were implanted but the level of expression was found to be decreased as time passed. Within the limitations of the present study, in this animal model, the transplantation of d-hMSCs enhanced the new bone formation around an implant and the survival and function of the stem cells was experimentally proven up to 12 weeks post-sacrifice.

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In Vivo and In Vitro Evaluation of Coated HAp Films with Different Surface Morphology

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.710 ◽

2007 ◽

Vol 539-543 ◽

pp. 710-715

Author(s):

Kotaro Kuroda ◽

Ryoichi Ichino ◽

Masazumi Okido

Keyword(s):

Bone Formation ◽

Surface Morphology ◽

New Bone Formation ◽

Contact Ratio ◽

Bone Implant ◽

Ft Ir ◽

Mouse Osteoblast ◽

Surface Morphologies

Hydroxyapatite (HAp) coatings were formed on cp titanium plates and rods by the thermal substrate method in an aqueous solution that included 0.3 mM Ca(H2PO4)2 and 0.7 mM CaCl2. The coating experiments were conducted at 40-140 oC and pH = 8 for 15 or 30 min. The properties for the coated samples were studied using XRD, EDX, FT-IR, and SEM. All the specimens were covered with HAp, which had different surface morphologies such as net-like, plate-like and needle-like. After cleaning and sterilization, all the coated specimens were subjected to in vivo and vitro testing. In the in vitro testing, the mouse osteoblast-like cells (MC3T3-E1) were cultured on the coated and non-coated specimens for up to 30 days. Moreover, the specimens (φ2 x 5 mm) were implanted in rats femoral for up to 8 weeks, the osseoinductivity on them were evaluated. In in vitro evaluations, there were not significant differences between the different surface morphologies. In in vivo evaluations, however, two weeks postimplantation, new bone formed on both the HAp coated and non-coated titanium rods in the cancellous and cortical bone. The bone-implant contact ratio, which was used for the evaluation of new bone formation, was significantly dependent on the surface morphology of the HAp, and the results demonstrated that the needle-like coating appears to promote rapid bone formation.

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Developing Stability of Posterior Mandibular Implants Placed With Osteotome Expansion Technique Compared With Conventional Drilling Techniques

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-16-00101 ◽

2017 ◽

Vol 43 (2) ◽

pp. 131-138 ◽

Cited By ~ 1

Author(s):

Yen-Ting Lin ◽

Adrienne Hong ◽

Ying-Chin Peng ◽

Hsiang-Hsi Hong

Keyword(s):

Bone Density ◽

Surgical Techniques ◽

Primary Stability ◽

Conventional Technique ◽

Implant Stability ◽

Implant Stability Quotient ◽

Expansion Technique ◽

The Stability ◽

Conventional Drilling ◽

Secondary Stability

Clinical decisions regarding the stability and osseointegration of mandibular implants positioned using the bone expansion techniques are conflicting and limited. The objective was to evaluate the stability of implants placed using 2 surgical techniques, selected according to the initial width of the mandibular posterior edentulous ridge, with D3 bone density, during a 12-week period. Fifty-eight implants in 33 patients were evaluated. Thirty-two implants in 24 patients were positioned using the osteotome expansion technique, and 26 fixtures in 17 patients were installed using the conventional drilling technique. The implant stability quotient values were recorded at weeks 0, 1, 2, 3, 4, 6, 8, 10, and 12 postsurgery and evaluated using analysis of variance, independent, and paired t tests. Calibrated according to the stability reading of a 3.3-mm diameter implant, the osteotome expansion group was associated with a lower bone density than the conventional group (64.96 ± 6.25 vs 68.98 ± 5.06, P = .011). The osteotome expansion group achieved a comparable primary stability (ISQb-0, P = .124) and greater increases in secondary stability (ISQb-12, P = .07) than did the conventional technique. A D3 quality ridge with mild horizontal deficiency is expandable by using the osteotome expansion technique. Although the 2 groups presented similar implant stability quotient readings during the study period, the osteotome expansion technique showed significant improvement in secondary stability. The healing patterns for these techniques are therefore inconsistent.

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Quantitative Analysis of New Bone Formation in Various Bone Grafts by In - Vivo Tetracycline Labeling

The Journal of the Korean Orthopaedic Association ◽

10.4055/jkoa.1985.20.1.1 ◽

1985 ◽

Vol 20 (1) ◽

pp. 1

Author(s):

Sang Cheol Seong ◽

Young Min Kim ◽

Han Koo Lee ◽

In Ho Choi ◽

Moon Sang Chung ◽

...

Keyword(s):

Quantitative Analysis ◽

Bone Formation ◽

Bone Grafts ◽

New Bone Formation ◽

Tetracycline Labeling

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Bioglass Associated With Leukocyte-Poor Platelet-Rich Plasma in the Rabbit Maxillary Sinus: Histomorphometric, Densitometric, and Fractal Analysis

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-09-00072 ◽

2010 ◽

Vol 36 (5) ◽

pp. 333-343 ◽

Cited By ~ 10

Author(s):

Ivy Kiemle Trindade-Suedam ◽

Juliana Aparecida Najarro Dearo de Morais ◽

Rafael Silveira Faeda ◽

Fábio Renato Manzolli Leite ◽

Guilherme Monteiro Tosoni ◽

...

Keyword(s):

Fractal Dimension ◽

Bone Density ◽

Bone Formation ◽

Maxillary Sinus ◽

Platelet Rich Plasma ◽

Autogenous Bone ◽

New Bone Formation ◽

Mean Values ◽

Dimension Analysis ◽

Fractal Dimension Analysis

Abstract The objective of the present study was to evaluate the outcomes of autogenous bone graft (AB) and bioglass (BG) associated or not with leukocyte-poor platelet-rich plasma (LP-PRP) in the rabbit maxillary sinus (MS) by histomorphometric and radiographic analysis. Twenty rabbits divided into 2 groups (G1, G2) were submitted to sinus lift surgery. In G1, 10 MS were grafted with AB and 10 MS were grafted with BG. In G2, 10 MS were grafted with AB + LP-PRP and 10 MS were grafted with BG + LP-PRP. After 90 days, the animals were killed and specimens were obtained, x-rayed, and submitted to histomorphometric, radiographic bone density (RD) and fractal dimension analysis. Radiographic bone density mean values (SD), expressed as aluminum equivalent in mm, of AB, BG, AB + LP-PRP, and BG + LP-PRP groups were 1.79 (0.31), 2.04 (0.39), 1.61 (0.28), and 1.53 (0.30), respectively. Significant differences (P < 0.05) were observed between BG and AB, and BG + PRP and BG. Fractal dimension mean values were 1.48 (0.04), 1.35 (0.08), 1.44 (0.04), and 1.44 (0.06), respectively. Significant differences were observed between BG and AB, and AB + LP-PRP and BG. Mean values for the percentage of bone inside MS were 63.30 (8.60), 52.65 (10.41), 55.25 (7.01), and 51.07 (10.25), respectively. No differences were found. No correlations were observed among percentage of bone, RD and FD. Histological analysis showed that MS treated with AB presented mature and new bone formation. The other groups showed minor bone formation. Within the limitations of this study, the results indicated that at a 90-day time end point, AB yielded better results than AB + LP-PRP, BG, and BG + LP-PRP and should be considered the primary material for MS augmentation.

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Primary Stability Optimization by Using Fixtures with Different Thread Depth According To Bone Density: A Clinical Prospective Study on Early Loaded Implants

Materials ◽

10.3390/ma12152398 ◽

2019 ◽

Vol 12 (15) ◽

pp. 2398 ◽

Cited By ~ 8

Author(s):

Christian Makary ◽

Abdallah Menhall ◽

Carole Zammarie ◽

Teresa Lombardi ◽

Seung Yeup Lee ◽

...

Keyword(s):

Bone Density ◽

Primary Stability ◽

Stability Loss ◽

Insertion Torque ◽

Implant Stability ◽

Marginal Bone Loss ◽

Early Loading ◽

Bone Level ◽

Implant Therapy ◽

Provisional Restoration

Background: Macro- and micro-geometry are among the factors influencing implant stability and potentially determining loading protocol. The purpose of this study was to test a protocol for early loading by controlling implant stability with the selection of fixtures with different thread depth according to the bone density of the implant site. Materials and Methods: Patients needing implant therapy for fixed prosthetic rehabilitation were treated by inserting fixtures with four different thread diameters, selected based on clinical assessment of bone quality at placement (D1, D2, D3, and D4, according to Misch classification). Final insertion torque (IT) and implant stability quotient (ISQ) were recorded at baseline and ISQ measurements repeated after one, two, three, and four weeks. At the three-week measurement (four weeks after implant replacement), implants with ISQ > 70 Ncm were functionally loaded with provisional restorations. Marginal bone level was radiographically measured 12 months after implant insertion. Results: Fourteen patients were treated with the insertion of forty implants: Among them, 39 implants showing ISQ > 70 after 3 weeks of healing were loaded with provisional restoration. Mean IT value was 82.3 ± 33.2 Ncm and varied between the four different types of bone (107.2 ± 35.6 Ncm, 74.7 ± 14.0 Ncm, 76.5 ± 31.1 Ncm, and 55.2 ± 22.6 Ncm in D1, D2, D3, and D4 bone, respectively). Results showed significant differences except between D2 and D3 bone types. Mean ISQ at baseline was 79.3 ± 4.3 and values in D1, D2, D3, and D4 bone were 81.9 ± 2.0, 81.1 ± 1.0, 78.3 ± 3.7, and 73.2 ± 4.9, respectively. Results showed significant differences except between D1 and D2 bone types. IT and ISQ showed a significant positive correlation when analyzing the entire sample (p = 0.0002) and D4 bone type (p = 0.0008). The correlation between IT and ISQ was not significant when considering D1, D2, and D3 types (p = 0.28; p = 0.31; p = 0.16, respectively). ISQ values showed a slight drop at three weeks for D1, D2, and D3 bone while remaining almost unchanged in D4 bone. At 12-month follow-up, all implants (39 early loading, 1 conventional loading) had satisfactory function, showing an average marginal bone loss of 0.12 ± 0.12 mm, when compared to baseline levels. Conclusion: Matching implant macro-geometry to bone density can lead to adequate implant stability both in hard and soft bone. High primary stability and limited implant stability loss during the first month of healing could allow the application of early loading protocols with predictable clinical outcomes.

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In Vitro and In Vivo Evaluation Of Calcium Phosphate Bone Graft Substitutes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.2065 ◽

2010 ◽

Vol 654-656 ◽

pp. 2065-2070

Author(s):

Ho Yeon Song ◽

Young Hee Kim ◽

Jyoti M. Anirban ◽

In Seon Byun ◽

Kyung A Kwak ◽

...

Keyword(s):

Calcium Phosphate ◽

Bone Formation ◽

Bone Graft ◽

Cellular Proliferation ◽

New Bone Formation ◽

Hydroxy Apatite ◽

Defect Sites ◽

Bone Graft Substitutes

Calcium phosphate ceramics such as hydroxy apatite (HA), β-tricalcium phosphate (β-TCP) and bicalcium phosphate (BCP) have been used as a bone graft biomaterial because of their good biocompatibility and similarity of chemical composition to natural bones. To increase the mechanical and osteoconductive properties, the granules and spongy type porous bone graft substitutes were prepared by fibrous monolithic process and polyurethane foam replica methods, respectively. The pore sizes obtained using these approaches ranged between 100-600 µm. The cytotoxicity, cellular proliferation, differentiation and ECM deposition on the bone graft substitutes were observed by SEM and confocal microscopy. Moreover, the scaffolds were implanted in the rabbit femur. New bone formation and biodegradation of bone graft were observed through follow-up X-ray, micro-CT analysis and histological findings. After several months (2, 3, 6, 12 and 24 months) of implantation, new bone formation and ingrowths were observed in defect sites of the animal by CaP ceramics and 2 to 3 times higher bone ingrowths were confirmed than that of the normal trabecular bones in terms of total bone volume (BV).

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