| 1. |
- Albrektsson, Tomas, 1945, et al.
(författare)
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On inflammation-immunological balance theory—A critical apprehension of disease concepts around implants: Mucositis and marginal bone loss may represent normal conditions and not necessarily a state of disease
- 2019
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Ingår i: Clinical Implant Dentistry and Related Research. - : Wiley. - 1523-0899 .- 1708-8208. ; 21:1, s. 183-189
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Tidskriftsartikel (refereegranskat)abstract
- Background: Oral implants have displayed clinical survival results at the 95%-99% level for over 10 years of follow up. Nevertheless, some clinical researchers see implant disease as a most common phenomenon. Oral implants are regarded to display disease in the form of mucositis or peri-implantitis. One purpose of the present article is to investigate whether a state of disease is necessarily occurring when implants display soft tissue inflammation or partially lose their bony attachment. Another purpose of this article is to analyze the mode of defense for implants that are placed in a bacteria rich environment and to analyze when an obtained steady state between tissue and the foreign materials is disturbed. Materials and Methods: The present article is authored as a narrative review contribution. Results: Evidence is presented that further documents the fact that implants are but foreign bodies that elicit a foreign body response when placed in bone tissue. The foreign body response is characterized by a bony demarcation of implants in combination with a chronic inflammation in soft tissues. Oral implants survive in the bacteria-rich environments where they are placed due to a dual defense system in form of chronic inflammation coupled to immunological cellular actions. Clear evidence is presented that questions the automatic diagnostics of an oral implant disease based on the finding of so called mucositis that in many instances represents but a normal tissue response to foreign body implants instead of disease. Furthermore, neither is marginal bone loss around implants necessarily indicative of a disease; the challenge to the implant represented by bone resorption may be successfully counteracted by local defense mechanisms and a new tissue-implant steady state may evolve. Similar reactions including chronic inflammation occur in the interface of orthopedic implants that display similarly good long-term results as do oral implants, if mainly evaluated based on revision surgery in orthopedic cases. The most common mode of failure of orthopedic implants is aseptic loosening which has been found coupled to a reactivation of the inflammatory- immune system. Conclusions: Implants survive in the body due to balanced defense reactions in form of chronic inflammation and activation of the innate immune system. Ten year results of oral and hip /knee implants are hence in the 90+ percentage region. Clinical problems may occur with bone resorption that in most cases is successfully counterbalanced by the defense/healing systems. However, in certain instances implant failure will ensue characterized by bacterial attacks and/or by reactivation of the immune system that now will act to remove the foreign bodies from the tissues.
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| 2. |
- Albrektsson, Tomas, 1945, et al.
(författare)
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On osseointegration in relation to implant surfaces
- 2019
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Ingår i: Clinical Implant Dentistry and Related Research. - : Wiley. - 1523-0899 .- 1708-8208. ; 21, s. 4-7
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Tidskriftsartikel (refereegranskat)abstract
- Background The understanding of mechanisms of osseointegration as well as applied knowledge about oral implant surfaces are of paramount importance for successful clinical results. Purpose The aim of the present article is to present an overview of osseointegration mechanisms and an introduction to surface innovations with relevance for osseointegration that will be published in the same supplement of Clinical Implant Dentistry and Related Research. Materials and Methods The present article is a narrative review of some osseointegration and implant surface-related details. Results and Conclusions Osseointegration has a changed definition since it is realized today that oral implants are but foreign bodies and that this fact explains osseointegration as a protection mechanism of the tissues. Given adequate stability, bone tissue is formed around titanium implants to shield them from the tissues. Oral implant surfaces may be characterized by microroughness and nanoroughness, by surface chemical composition and by physical and mechanical parameters. An isotropic, moderately rough implant surface such as seen on the TiUnite device has displayed improved clinical results compared to previously used minimally rough or rough surfaces. However, there is a lack of clinical evidence supporting any particular type of nanoroughness pattern that, at best, is documented with results from animal studies. It is possible, but as yet unproven, that clinical results may be supported by a certain chemical composition of the implant surface. The same can be said with respect to hydrophilicity of implant surfaces; positive animal data may suggest some promise, but there is a lack of clinical evidence that hydrophilic implants result in improved clinical outcome of more hydrophobic surfaces. With respect to mechanical properties, it seems obvious that those must be encompassing the loading of oral implants, but we need more research on the mechanically ideal implant surface from a clinical aspect.
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| 3. |
- Albrektsson, Tomas, 1945, et al.
(författare)
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Overview of surface Microtopography/Chemistry/Physics/Nano-roughness
- 2015
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Ingår i: Implant Surfaces and their Biological and Clinical Impact. - Berlin, Heidelberg : Springer. - 9783662453797 ; , s. 7-12
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Bokkapitel (refereegranskat)abstract
- The implant surface has since long been recognised as important for the host response to oral implants. When the implant is inserted in the body, blood will immediately cover the implant surface. Different surface properties may trigger proteins and signalling system to enhance and speed up the healing process. The implant surface can be altered with respect to topography, chemistry, physics and mechanical properties. In particular, so far the surface topography and chemistry have gained the greatest interest from researchers and manufacturers of oral implants. © Springer-Verlag Berlin Heidelberg 2015.
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| 4. |
- Alenezi, Ali, et al.
(författare)
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Osseointegration effects of local release of strontium ranelate from implant surfaces in rats
- 2019
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Ingår i: Journal of Materials Science: Materials in Medicine. - : Springer Science and Business Media LLC. - 0957-4530 .- 1573-4838. ; 30:10, s. 116-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND : Numerous studies have reported the beneficial effects of strontium on bone growth, particularly by stimulating osteoblast proliferation and differentiation. Thus, strontium release around implants has been suggested as one possible strategy to enhance implant osseointegration. AIM : This study aimed to evaluate whether the local release of strontium ranelate (Sr-ranelate) from implants coated with mesoporous titania could improve bone formation around implants in an animal model. MATERIALS AND METHODS : Mesoporous titania (MT) thin coatings were formed utilizing the evaporation induced self-assembly (EISA) method using Pluronic (P123) with or without the addition of poly propylene glycol (PPG) to create materials with two different pore sizes. The MT was deposited on disks and mini-screws, both made of cp Ti grade IV. Scanning electron microscopy (SEM) was performed to characterize the MT using a Leo Ultra55 FEG instrument (Zeiss, Oberkochen, Germany). The MT was loaded with Sr-ranelate using soaking and the drug uptake and release kinetics to and from the surfaces were evaluated using quartz crystal microbalance with dissipation monitoring (QCM-D) utilizing a Q-sense E4 instrument. For the in vivo experiment, 24 adult rats were analyzed at two time points of implant healing (2 and 6 weeks). Titanium implants shaped as mini screws were coated with MT films and divided into two groups; supplied with Sr-ranelate (test group) and without Sr-ranelate (control group). Four implants (both test and control) were inserted in the tibia of each rat. The in vivo study was evaluated using histomorphometric analyses of the implant/bone interphase using optical microscopy. RESULTS : SEM images showed the successful formation of evenly distributed MT films covering the entire surface with pore sizes of 6 and 7.2 nm, respectively. The QCM-D analysis revealed an absorption of 3300 ng/cm2 of Sr-ranelate on the 7.2 nm MT, which was about 3 times more than the observed amount on the 6 nm MT (1200 ng/cm2). Both groups showed sustained release of Sr-ranelate from MT coated disks. The histomorphometric analysis revealed no significant differences in bone implant contact (BIC) and bone area (BA) between the implants with Sr-ranelate and implants in the control groups after 2 and 6 weeks of healing (BIC with a p-value of 0.43 after 2 weeks and 0.172 after 6 weeks; BA with a p-value of 0.503 after 2 weeks, and 0.088 after 6 weeks). The mean BIC and BA values within the same group showed significant increase among all groups between 2 and 6 weeks. CONCLUSION : This study could not confirm any positive effects of Sr-ranelate on implant osseointegration.
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| 5. |
- Braian, Michael, et al.
(författare)
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Trueness and precision of 5 intraoral scanners for scanning edentulous and dentate complete-arch mandibular casts: A comparative in vitro study
- 2019
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Ingår i: Journal of Prosthetic Dentistry. - : Elsevier BV. - 0022-3913 .- 1097-6841. ; 122:2, s. 129-136
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Tidskriftsartikel (refereegranskat)abstract
- Statement of problem. Limited information is available on the trueness and precision of intraoral scanners (IOSs) for scanning dentate and edentulous casts. Purpose. The purpose of this in vitro study was to evaluate the trueness and precision of 5 different IOS devices for scanning a dentate and an edentulous cast in a standardized way for short arches and complete arches. Material and methods. Five IOS devices were used to scan 2 computer metric measured casts using a coordinate measuring machine (CMM). Both were scanned 15 times. All scans were carried out by 1 experienced operator in a standardized way. One cast was edentulous, and 1 was dentate. Five cylindrical landmarks were added to each cast. These cylinders made the measurement of point-to-point distances possible, dividing the tests into cross-arch measurements and intercylindrical (short-arch) measurements. The Student t test, Mann-Whitney test, and Levene test for equality were used to calculate the difference between the edentulous and dentate scans for both cross-arch and intercylindrical measurements (alpha=.05). Results. For the cross-arch measurements on the edentulous scans, the trueness values ranged between 6 mu m (Emerald P1-P2) and 193 mu m (Omnicam P1-P5) and for the intercylindrical measurements, between 2 mu m (Itero P4-P5) and -103 mu m (CS 3600 P1-P2). For the dentate cast, the cross-arch trueness values ranged between 6 mu m (CS 3600 P1-P2) and 150 mu m (TRIOS 3 P1-P5) and for the intercylindrical measurements, between 4 mu m (Itero P4-P5) and -56 mu m (Emerald P4-P5). Conclusions. Significant differences were found in scanning edentulous and dentate scans for short arches and complete arches. Trueness for complete-arch scans were <193 mu m for edentulous scans and <150 mu m for dentate scans. Trueness for short-arch scans were <103 mu m for edentulous scans and <56 mu m for dentate scans.
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| 6. |
- Chrcanovic, Bruno, et al.
(författare)
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Bruxism and dental implant treatment complications: a retrospective comparative study of 98 bruxer patients and a matched group.
- 2017
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Ingår i: Clinical oral implants research. - : Wiley. - 1600-0501 .- 0905-7161. ; 28:7
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Tidskriftsartikel (refereegranskat)abstract
- Objectives To analyze the complications of dental implant treatment in a group of patients with bruxism in comparison with a matched group of non‐bruxers. Material and methods Patients being diagnosed as bruxers were identified within a group of patients consecutively treated with implant‐supported prostheses at one specialist clinic, based on the most recent listed sign and symptoms of bruxism according to the International Classification of Sleep Disorders. A diagnostic grading system of “possible,” “probable,” and “definite” sleep or awake bruxism was used, according to a recent published international consensus. A case–control matching model was used to match the bruxers with a group of non‐bruxers, based on five variables. Implant‐, prosthetic‐, and patient‐related data were collected, as well as 14 mechanical complications, and compared between groups. Results Ninety‐eight of 2670 patients were identified as bruxers. The odds ratio of implant failure in bruxers in relation to non‐bruxers was 2.71 (95% CI 1.25, 5.88). Considering the same number of patients with the same total number of implants equally distributed between groups, the bruxers group had a higher prevalence of mechanical complications in comparison with the non‐bruxers group. Conclusions This study suggests that bruxism may significantly increase both the implant failure rate and the rate of mechanical and technical complications of implant‐supported restorations. Other risk factors may also have influenced the results.
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| 7. |
- Chrcanovic, Bruno, et al.
(författare)
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Bruxism and Dental Implants: A Meta-Analysis.
- 2015
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Ingår i: Implant dentistry. - : Lippincott Williams & Wilkins. - 1538-2982 .- 1056-6163. ; 24:5, s. 505-516
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Tidskriftsartikel (refereegranskat)abstract
- To test the null hypothesis of no difference in the implant failure rates, postoperative infection, and marginal bone loss after the insertion of dental implants in bruxers compared with the insertion in non-bruxers against the alternative hypothesis of a difference.
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| 8. |
- Chrcanovic, Bruno, et al.
(författare)
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Dental implants inserted in male versus female patients: a systematic review and meta-analysis.
- 2015
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Ingår i: Journal of oral rehabilitation. - : Wiley. - 1365-2842 .- 0305-182X. ; 42:9, s. 709-722
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this meta-analysis was to test the null hypothesis of no difference in the failure rates, marginal bone loss (MBL) and post-operative infection for implants inserted in male or female patients, against the alternative hypothesis of a difference. An electronic search without time or language restrictions was undertaken in December 2014. Eligibility criteria included clinical human studies, either randomized or not. Ninety-one publications were included, with a total of 27203 implants inserted in men (1185 failures), and 25154 implants inserted in women (1039 failures). The results suggest that the insertion of dental implants in male patients statistically affected the implant failure rates (RR 1·21, 95% CI 1·07-1·37, P=0·002). Due to the limited number of studies reporting results on MBL, it is difficult to estimate the real effect of the insertion of implants in different sexes on the marginal bone level. Due to lack of satisfactory information, meta-analysis for the outcome 'post-operative infection' was not performed. The results have to be interpreted with caution due to the presence of several confounding factors in the included studies.
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| 9. |
- Chrcanovic, Bruno, et al.
(författare)
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Factors Influencing Early Dental Implant Failures
- 2016
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Ingår i: Journal of Dental Research. - : SAGE Publications. - 0022-0345 .- 1544-0591. ; 95:9, s. 995-1002
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the present study was to assess the influence of local and systemic factors on the occurrence of dental implant failures up to the second-stage surgery (abutment connection). This retrospective study is based on 2,670 patients who received 10,096 implants and were consecutively treated with implant-supported prostheses between 1980 and 2014 at 1 specialist clinic. Several anatomic-, patient-, health-, and implant-related factors were collected. Descriptive statistics were used to describe the patients and implants. Univariate and multivariate logistic regression models were used at the patient level as well as the implant level to evaluate the effect of explanatory variables on the failure of implants up to abutment connection. A generalized estimating equation method was used for the implant-level analysis to account for the fact that repeated observations (several implants) were available for a single patient. Overall, 642 implants (6.36%) failed, of which 176 (1.74%) in 139 patients were lost up to second-stage surgery. The distribution of implants in sites of different bone quantities and qualities was quite similar between implants lost up to and after abutment connection. Smoking and the intake of antidepressants were the statistically significant predictors in the multivariate model (ClinicalTrials. gov NCT02369562).
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| 10. |
- Chrcanovic, Bruno, et al.
(författare)
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Immediately loaded non-submerged versus delayed loaded submerged dental implants: A meta-analysis.
- 2015
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Ingår i: International Journal of Oral & Maxillofacial Surgery. - : Elsevier BV. - 0901-5027 .- 1399-0020. ; 44:4, s. 493-506
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the present meta-analysis was to test the null hypothesis of no difference in the implant failure rate, postoperative infection, and marginal bone loss for patients being rehabilitated with immediately loaded non-submerged dental implants or delayed loaded submerged implants, against the alternative hypothesis of a difference. An electronic search without time or language restrictions was undertaken in March 2014. Eligibility criteria included clinical human studies, either randomized or not. The search strategy resulted in 28 publications. The inverse variance method was used for a random- or fixed-effects model, depending on the heterogeneity. The estimates of an intervention were expressed as the risk ratio (RR) and mean difference (MD) in millimetres. Twenty-three studies were judged to be at high risk of bias, one at moderate risk of bias, and four studies were considered at low risk of bias. The difference between procedures (submerged vs. non-submerged implants) significantly affected the implant failure rate (P=0.02), with a RR of 1.78 (95% confidence interval (CI) 1.12-2.83). There was no apparent significant effect of non-submerged dental implants on the occurrence of postoperative infection (P=0.29; RR 2.13, CI 0.52-8.65) or on marginal bone loss (P=0.77; MD -0.03, 95% CI -0.23 to 0.17).
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