scholarly journals Mechanical and Biological Advantages of a Tri-Oval Implant Design

2019 ◽  
Vol 8 (4) ◽  
pp. 427 ◽  
Author(s):  
Xing Yin ◽  
Jingtao Li ◽  
Waldemar Hoffmann ◽  
Angelines Gasser ◽  
John Brunski ◽  
...  

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.

2019 ◽  
Vol 2019 ◽  
pp. 1-4 ◽  
Author(s):  
Antonio Scarano ◽  
Bartolomeo Assenza ◽  
Francesco Inchingolo ◽  
Filiberto Mastrangelo ◽  
Felice Lorusso

Background. The immediate placement of a dental implant could represent an option treatment for the rehabilitation of a postextractive missing tooth socket to replace compromised or untreatable teeth, with the advantage of single-session surgery. In this way, the anatomy of the alveolar bone defect, the preservation of the buccal cortical bone, and the primary stability of the fixture represent the critical factors that consent a precise implant placement. Objective. This case report describes a novel fixture design for postextractive alveolar socket immediate implant. Methods. Two patients (25 and 31 years old) were treated for postextractive dental implant placement to replace both central upper incisor teeth with four implants. The residual bone implant gap was not filled with graft or bone substitute. The restoration was provided following a standard loading protocol by a cement-sealed prosthetic abutment. Results. Clinically, all implants positioned showed an excellent insertion torque. No postoperative complications were reported. At 6 months of healing, the buccal cortical bone and the implant stability were present and well maintained. Conclusion. The evidence of this study allows us to underline the possible advantages of this new fixture design for postextractive implant technique.


2020 ◽  
Vol 9 (2) ◽  
pp. 60-70 ◽  
Author(s):  
Zhijun Li ◽  
Masaki Arioka ◽  
Yindong Liu ◽  
Maziar Aghvami ◽  
Serdar Tulu ◽  
...  

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.


2021 ◽  
Author(s):  
Rafael Coutinho Mello-Machado ◽  
Suelen Cristina Sartoretto ◽  
Jose Mauro Granjeiro ◽  
José Albuquerque Calasans-Maia ◽  
Marcelo Jose Guedes Pinheiro Uzeda ◽  
...  

Abstract This study aimed to investigate in vivo the hypothesis that the osseodensification technique, through a wider osteotomy, produce healing chambers at the implant-bone interface with no impact on primary stability osseointegration in low-density bone. Twenty implants (3.5 x 10 mm) presenting nanohydroxyapatite (nHA) surface were inserted in the ilium of ten sheep, after preparation of a 2.7-mm wide implant bed with conventional subtractive drilling (SCD) or a 3.8-mm wide implant bed with an osseodensification bur system (OBS) (n = 5/group/period). The final insertion torque (IT) and implant stability quotient (ISQ) evaluated the primary implant stability. After 14 and 28 days, the bone samples containing the implants were processed for histological and histomorphometric evaluation of bone implant contact (BIC) and bone area fraction occupancy (BAFO). No significant differences occurred between the implant bed preparations regarding IT and ISQ (P > 0.05). Histological analysis showed bone remodeling, and bone growth in all samples with no inflammatory infiltrate. BIC values were higher for SCD after 14 and 28 days (p < 0.05), however BAFO values were similar on both groups (p > 0.05). It was possible to conclude that the osseodensification technique allowed a wider implant bed preparation with no prejudice on primary stability and bone remodeling.


Author(s):  
Mariano Herrero-Climent ◽  
Bernardo Ferreira Lemos ◽  
Federico Herrero-Climent ◽  
Carlos Falcao ◽  
Helder Oliveira ◽  
...  

The aim of this study was to evaluate the effects of different implant sites an under-preparation sequence associated with two different implant designs on implant primary stability measured by two parameters: insertion torque (IT) and implant stability quotient (ISQ). It used two different implants: one cylindrical as a control and another one with a tapered design. The implants were inserted in type III fresh humid bovine bone and four drilling sequences were used: one control, the one proposed by the implant company (P1), and three different undersized (P2, P3 and P4). P2 was the same as P1 without the cortical drill, P3 was without the last pilot drill and P4 was without both of them. The sample size was n = 40 for each of the eight groups. Final IT was measured with a torquemeter and the ISQ was measured with Penguin resonance frequency analysis. Results showed that both ISQ and IT have a tendency to increase as the preparation technique reduces the implant site diameter when compared with the standard preparation, P1. The preparations without cortical drill, P2 and P4, showed the best results when compared with the ones with a cortical drill. Tapered implants always showed higher or the same ISQ and IT values when compared with the cylindrical implants. Giving the limitations of this study, it can be concluded that reducing implant preparation can increase IT and ISQ values. Removing the cortical drill and the use of a tapered design implant are also effective methods of increasing primary implant stability.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rafael Coutinho Mello-Machado ◽  
Suelen Cristina Sartoretto ◽  
Jose Mauro Granjeiro ◽  
José de Albuquerque Calasans-Maia ◽  
Marcelo Jose Pinheiro Guedes de Uzeda ◽  
...  

AbstractPrimary implant stability is a prerequisite for successful implant osseointegration. The osseodensification technique (OD) is a non-subtractive drilling technique that preserves the bone tissue, increases osteotomy wall density, and improves the primary stability. This study aimed to investigate the hypothesis that OD, through a wider osteotomy, produces healing chambers (HCs) at the implant-bone interface without impacting low-density bone primary stability. Twenty implants (3.5 × 10 mm) with a nanohydroxyapatite (nHA) surface were inserted in the ilium of ten sheep. Implant beds were prepared as follows: (i) 2.7-mm-wide using subtractive conventional drilling (SCD) technique (n = 10); (ii) 3.8-mm-wide using an OD bur system (n = 10). The sheep were randomized to two groups, with samples collected at either 14-(n = 5) or 28-days (n = 5) post-surgery and processed for histological and histomorphometric evaluation of bone-implant contact (BIC) and bone area fraction occupancy (BAFO). No significant group differences were found with respect to final insertion torque and implant stability quotient (p > 0.050). BIC values were higher for SCD after 14 and 28 days (p < 0.050); however, BAFO values were similar (p > 0.050). It was possible to conclude that the OD technique allowed a wider implant bed preparation without prejudice on primary stability and bone remodeling.


2021 ◽  
Vol 11 (12) ◽  
pp. 5612
Author(s):  
Stefano Fanali ◽  
Margherita Tumedei ◽  
Pamela Pignatelli ◽  
Alessandra Lucchese ◽  
Francesco Inchingolo ◽  
...  

Background: Implant primary stability can be affected by several factors related to implant macrogeometry, local anatomy, and surgical techniques. The aim of this research was to study primary stability on polyurethane foam sheets of wide-threaded implant design compared to narrow-threaded implants. Materials and methods: Two different implant designs were positioned on D3 density polyurethane blocks in a standardized environment: the wide-threaded implant and the narrow-threaded implant, for a total of 160 specimens. Moreover, for each group, two different sizes were considered: 3.8mm × 12mm and 4.8mm × 12 mm. The insertion torque (IT) values, the removal strength (RT), and the Periotest analyses were evaluated. Results: A significantly higher IT and RT was reported for wide-threaded implants and two-stage implants (p < 0.01), compared to the narrow-threaded implants. The diameters seemed to provide a significant effect on the primary stability for both implants’ geometry (p < 0.01). A higher mean of the one-stage implant was evident in the Periotest measurements (p < 0.01). Conclusions: Both of the implants showed sufficient stability in polyurethane artificial simulation, while the wide-threaded implant design showed a higher primary stability on alveolar cancellous synthetic bone in vitro. Additionally, the prosthetic joint connection seemed to have a determinant effect on Periotest analysis, and the one-stage implants seemed to provide a high stability of the fixture when positioned in the osteotomy, which could be important for the immediate loading protocol.


2013 ◽  
Vol 70 (6) ◽  
pp. 586-594 ◽  
Author(s):  
Zoran Vlahovic ◽  
Branko Mihailovic ◽  
Zoran Lazic ◽  
Mileta Golubovic

Background/Aim. Flapless implant surgery has become very important issue during recent years, mostly thanks to computerization of dentistry and software planning of dental implants placements. The aim of this study was to compare flap and flapless surgical techniques for implant placement through radiographic and radiofrequency analyses. Methods. The experiment was made in five domestic pigs. Nine weeks following domestic pigs teeth extraction, implants were placed, on the right side using surgical technique flap, and flapless on the left side. Digital dental Xrays were applied to determine primary dental implant stability quality (ISQ). At certain intervals, not later than three months, the experimental animals were sacrificed, and just before it, control X-rays were applied to measure dental implants stability. Results. Radiographic analysis showed that peri-implant bone resorption in the first 4 weeks following placement implants with flap and flapless surgical techniques was negligible. After the 3 months, mean value of peri-implant bone resorption of the implants placed using flap technique was 1.86 mm, and of those placed using flapless technique was 1.13 mm. In relation to the primary dental implant stability in the first and second week there was an expected decrease in ISQ values, but it was less expressed in the dental implants placed using the flapless technique. In the third week the ISQ values were increased in the dental implants placed by using both techniques, but the increase in flapless implant placement was higher (7.4 ISQ) than in flap implant placement (1.5 ISQ). The upward trend continued in a 4- week period, and after 3 months the dental implant stability values in the implants placed using flap technique were higher than the primary stability for 7.1 ISQ, and in the implants placed using flapless technique were higher comparing to the primary stability for 10.1 ISQ units. Conclusion. Based on the results of radiographic and resonance frequency analyses it can be concluded that the flapless technique in surgical implants placemat, leads to better results.


2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Fernanda Faot ◽  
Amália Machado Bielemann ◽  
Alessandra Julie Schuster ◽  
Raissa Micaella Marcello-Machado ◽  
Altair Antoninha Del Bel Cury ◽  
...  

Aim. To evaluate the influence of primary insertion torque (IT) values of narrow dental implants on the peri-implant health, implant stability, immunoinflammatory responses, bone loss, and success and survival rates. Methods. Thirty-one edentulous patients received two narrow implants (2.9x10mm, Facility NeoPoros) to retain mandibular overdentures. The implants were categorized in four groups according to their IT: (G1) IT > 10 Ncm; (G2) IT ≥ 10Ncm and ≤ 30 Ncm; (G3) IT >30Ncm and < 45Ncm; (G4) IT ≥ 45Ncm, and all implants were loaded after 3 months of healing. The following clinical outcomes were evaluated 1, 3, 6, and 12 months after implant insertion: (i) peri-implant tissue health (PH), gingival index (GI), plaque index (PI), calculus presence (CP), probing depth (PD), and bleeding on probing (BOP); (ii) implant stability quotient (ISQ) by resonance frequency analysis; and (iii) IL-1β and TNF-α concentration in the peri-implant crevicular fluid. The marginal bone level (MBL) and changes (MBC) were evaluated. The Chi2 test, Kruskal-Wallis test, mixed-effects regression analysis, and the Kendall rank correlation coefficient were used for statistical analysis (α = 5%). Results. G1 presented the highest PD at all evaluated periods. G2 presented higher PI at month 6 and 12. G4 showed increased GI at month 3 and 12 and more CP at month 1 (p=.003). G2 and G4 had higher ISQ values over the study period, while those from G1 and G3 presented lower ISQ values. The IL-1β concentration increased until month 12 and was independent of IT and bone type; G4 had a higher IL-1β concentration in month 3 than the other groups (p=.015). The TNF-α release was negatively correlated with IT, and TNF-α release was highest in G1 at month 12. The MBL immediately after surgery and the MBC at month 12 were similar between the groups, and G4 presented a positive MBC at month 12. The survival and success rates were 75% for G1, 81.3% for G2, 64.3% for G3, and 95% for G4. Conclusion. The IT did not influence the clinical outcomes and the peri-implant immunoinflammatory responses and was weakly correlated with the narrow dental implants primary stability. The observed success rates suggest that the ideal IT for atrophic fully edentulous patients may deviate from the standardized IT of 32 Ncm.


Materials ◽  
2019 ◽  
Vol 12 (15) ◽  
pp. 2398 ◽  
Author(s):  
Christian Makary ◽  
Abdallah Menhall ◽  
Carole Zammarie ◽  
Teresa Lombardi ◽  
Seung Yeup Lee ◽  
...  

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.


Author(s):  
Bernardo Ferreira Lemos ◽  
Paula Lopez-Jarana ◽  
Carlos Falcao ◽  
Blanca Ríos-Carrasco ◽  
Javier Gil ◽  
...  

As immediate loading protocols are becoming more frequent, the primary stability of implants has become an essential criterion for the osseointegration of dental implants. Based on this, the objective of this study was to understand the influence of different undersized surgical preparation sites on the insertion torque (IT) and implant stability quotient (ISQ). Four different site-preparation protocols were performed on fresh humid type III bovine bone: one control, the standard protocol recommended by the manufacturer (P1), and three variations of undersized techniques (P2, P3 and P4). The implant used was VEGA by Klockner Implant System. The sample size was n = 40 for each of the four groups. A torquemeter was used to measure the IT, and the ISQ was measured with a Penguin RFA. Both variables showed a tendency to increase as the preparation technique was reduced, although not all the values were statistically significant (p < 0.05) when comparing with the standard preparation. The preparations without a cortical drill, P2 and P4, showed better results than those with a cortical drill. Given the limitations of this study, it can be concluded that reducing the implant preparation can increase both the IT and ISQ. Removing the cortical drill is an effective method for increasing implant stability, although it should be used carefully.


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