Clinical Oral Implants Research
1600-0501
0905-7161
Đan mạch
Cơ quản chủ quản: Blackwell Munksgaard , WILEY
Lĩnh vực:
Oral Surgery
Phân tích ảnh hưởng
Thông tin về tạp chí
Clinical Oral Implants Research conveys scientific progress in the field of implant dentistry and its related areas to clinicians, teachers and researchers concerned with the application of this information for the benefit of patients in need of oral implants. The journal addresses itself to clinicians, general practitioners, periodontists, oral and maxillofacial surgeons and prosthodontists, as well as to teachers, academicians and scholars involved in the education of professionals and in the scientific promotion of the field of implant dentistry.
Các bài báo tiêu biểu
Influence of forces on peri‐implant bone Abstract: Occlusal forces affect an oral implant and the surrounding bone. According to bone physiology theories, bones carrying mechanical loads adapt their strength to the load applied on it by bone modeling/remodeling. This also applies to bone surrounding an oral implant. The response to an increased mechanical stress below a certain threshold will be a strengthening of the bone by increasing the bone density or apposition of bone. On the other hand, fatigue micro‐damage resulting in bone resorption may be the result of mechanical stress beyond this threshold. In the present paper literature dealing with the relationship between forces on oral implants and the surrounding bone is reviewed. Randomized controlled as well as prospective cohorts studies were not found. Although the results are conflicting, animal experimental studies have shown that occlusal load might result in marginal bone loss around oral implants or complete loss of osseointegration. In clinical studies an association between the loading conditions and marginal bone loss around oral implants or complete loss of osseointegration has been stated, but a causative relationship has not been shown.
Tập 17 Số S2 - Trang 8-18 - 2006
The effects of cyclic loading and preparation on the fracture strength of zirconium-dioxide implants: an in vitro investigation
Tập 22 Số 8 - Trang 808-814 - 2011
Comparative evaluation of implant designs: influence of diameter, length, and taper on strains in the alveolar crest Abstract Objectives: Our aim was to analyze and compare systematically the relative and interactive effects of implant diameter, length, and taper on calculated crestal bone strains.Material and methods: Three‐dimensional finite‐element models were created of a 20‐mm premolar section of the mandible with a single endosseous implant embedded in high‐ or low‐density cancellous bone. Oblique (200‐N vertical and 40‐N horizontal) occlusal loading was applied. Cortical and cancellous bone were modeled as transversely isotropic and linearly elastic. Perfect bonding was assumed at all interfaces. A two‐level factorial statistical design was used to determine the main and interactive effects of four implant design variables on maximum shear strains in the crestal alveolar bone: diameter, length of tapered segment, length of untapered segment, and taper. Implant diameter ranged from 3.5 to 6 mm, total implant length from 5.75 to 23.5 mm, and taper from 0 to 14°, resulting in 16 implant designs.Results: Increasing implant diameter resulted in as much as a 3.5‐fold reduction in crestal strain, increasing length caused as much as a 1.65‐fold reduction, whereas taper increased crestal strain, especially in narrow and short implants, where it increased 1.65‐fold. Diameter, length, and taper have to be considered together because of their interactive effects on crestal bone strain.Conclusion: If the objective is to minimize peri‐implant strain in the crestal alveolar bone, a wide and relatively long, untapered implant appears to be the most favorable choice. Narrow, short implants with taper in the crestal region should be avoided, especially in low‐density bone.
Tập 16 Số 4 - Trang 486-494 - 2005
The effect of thread pattern upon implant osseointegration Abstract Objectives: Implant design features such as macro‐ and micro‐design may influence overall implant success. Limited information is currently available. Therefore, it is the purpose of this paper to examine these factors such as thread pitch, thread geometry, helix angle, thread depth and width as well as implant crestal module may affect implant stability.Search Strategy: A literature search was conducted using MEDLINE to identify studies, from simulated laboratory models, animal, to human, related to this topic using the keywords of implant thread, implant macrodesign, thread pitch, thread geometry, helix angle, thread depth, thread width and implant crestal module.Results: The results showed how thread geometry affects the distribution of stress forces around the implant. A decreased thread pitch may positively influence implant stability. Excess helix angles in spite of a faster insertion may jeopardize the ability of implants to sustain axial load. Deeper threads seem to have an important effect on the stabilization in poorer bone quality situations. The addition of threads or microthreads up to the crestal module of an implant might provide a potential positive contribution on bone‐to to‐implant contact as well as on the preservation of marginal bone; nonetheless this remains to be determined.Conclusions: Appraising the current literature on this subject and combining existing data to verify the presence of any association between the selected characteristics may be critical in the achievement of overall implant success. To cite this article:
Abuhussein H, Pagni G, Rebaudi A, Wang H‐L. The effect of thread pattern upon implant osseointegration.
Clin. Oral Impl. Res . 21 , 2010; 129–136.
doi: 10.1111/j.1600‐0501.2009.01800.x
Tập 21 Số 2 - Trang 129-136 - 2010
<i>In vitro</i> bone strain analysis of implant following occlusal overload Abstract Objectives To enumerate peri‐implant bone strain pattern under quantified occlusal load and verify the bone response through comparison with the critical strain thresholds defined by Frost's bone mechanostat theory. Material and Methods Mandibular unilateral recipient sites in two greyhound dogs were established with posterior teeth extractions. After 6 weeks, four titanium implants were placed in each dog mandible. Following 12 weeks of healing, successfully osseointegrated implants were placed in supra‐occlusal contact via screw‐retained non‐splinted metal crowns. Plaque control and a dental health enhancing diet were prescribed. A bite force detection device was used to quantify in vivo occlusal load as the dogs functioned with supra‐occlusal contact. After 8 weeks, the dogs were sacrificed. In vitro peri‐implant bone strain under quantified occlusal load was measured using bonded stacked rosette strain gauges. Results The average and peak in vivo occlusal load measured were 434 and 795 newton (N). When individually and simultaneously loaded in vitro (≤ 476 N), absolute bone strains up to 1133 and 753 microstrains (με) were measured at implant apices, respectively. Bone strain reaching 229 με was recorded at distant sites. For bone strain to reach the pathological overload threshold defined by Frost's bone mechanostat theory (3000 με), an occlusal load of 1344 N (greater than peak measured in vivo ) is required based on the simple linear regression model. Conclusion Under the in vivo and in vitro conditions investigated in this study, peri‐implant bone was not found to be under pathological overload following supra‐occlusal contact function. Strain dissipation to distant sites appeared to be an effective mechanism by which implant overload was avoided.
Tập 25 Số 2 - 2014
The influence of static and dynamic loading on marginal bone reactions around osseointegrated implants: an animal experimental study Abstract: Although it is generally accepted that adverse forces can impair osseointegration, the mechanism of this complication is unknown. In this study, static and dynamic loads were applied on 10 mm long implants (Brånemark System® , Nobel Biocare, Sweden) installed bicortically in rabbit tibiae to investigate the bone response. Each of 10 adult New Zealand black rabbits had one statically loaded implant (with a transverse force of 29.4 N applied on a distance of 1.5 mm from the top of the implant, resulting in a bending moment of 4.4 Ncm), one dynamically loaded implant (with a transverse force of 14.7 N applied on a distance of 50 mm from the top of the implant, resulting in a bending moment of 73.5 Ncm, 2.520 cycles in total, applied with a frequency of 1 Hz), and one unloaded control implant. The loading was performed during 14 days. A numerical model was used as a guideline for the applied dynamic load. Histomorphometrical quantifications of the bone to metal contact area and bone density lateral to the implant were performed on undecalcified and toluidine blue stained sections. The histological picture was similar for statically loaded and control implants. Dense cortical lamellar bone was present around the marginal and apical part of the latter implants with no signs of bone loss. Crater‐shaped bone defects and Howship’s lacunae were explicit signs of bone resorption in the marginal bone area around the dynamically loaded implants. Despite those bone defects, bone islands were present in contact with the implant surface in this marginal area. This resulted in no significantly lower bone‐to‐implant contact around the dynamically loaded implants in comparison with the statically loaded and the control implants. However, when comparing the amount of bone in the immediate surroundings of the marginal part of the implants, significantly (P <0.007) less bone volume (density) was present around the dynamically loaded in comparison with the statically loaded and the control implants. This study shows that excessive dynamic loads cause crater‐like bone defects lateral to osseointegrated implants.
Tập 12 Số 3 - Trang 207-218 - 2001
Dimension of the facial bone wall in the anterior maxilla: a cone‐beam computed tomography study Abstract Objective: To determine the thickness of the facial bone wall in the anterior dentition of the maxilla and at different locations apical to the cemento‐enamel junction (CEJ).Material and methods: Two‐hundred and fifty subjects, aged between 17 and 66 years, with all maxillary front teeth present were included. Written informed consents were obtained. Cone‐beam computed tomography scans were performed with the iCAT unit. This examination included all tooth and edentulous sites in the dentition. The images were acquired by means of the iCAT software and processed by a computer. Measurements of the (i) distance between the CEJ and the facial bone crest and (ii) the thickness of the facial bone wall were performed. The bone wall dimensions were assessed at three different positions in relation to the facial bone crest, i.e., at distances of 1, 3, and 5 mm apical to the crest.Results: The measurements demonstrated that (i) the distance between the CEJ and the facial bone crest varied between 1.6 and 3 mm and (ii) the facial bone wall in most locations in all tooth sites examined was ≤1 mm thick and that close to 50% of sites had a bone wall thickness that was ≤0.5 mm.Conclusion: Most tooth sites in the anterior maxilla have a thin facial bone wall. Such a thin bone wall may undergo marked dimensional diminution following tooth extraction. This fact must be considered before tooth removal and the planning of rehabilitation in the anterior segment of the dentition in the maxilla.To cite this article:
Januário AL, Duarte WR, Barriviera M, Mesti JC, Araújo MG, Lindhe J. Dimension of the facial bone wall in the anterior maxilla: a cone‐beam computed tomography study.
Clin. Oral Impl. Res . 22 , 2011; 1168–1171
doi: 10.1111/j.1600‐0501.2010.02086.x.
10.1111/j.1600‐0501.2010.02086.x
Tập 22 Số 10 - Trang 1168-1171 - 2011
Osseointegration enhanced by chemical etching of the titanium surface. A torque removal study in the rabbit. Roughened implant surfaces are thought to enhance osseointegration. Torque removal forces have been used as a biomechanical measure of anchorage or osseointegration in which the greater forces required to remove implants may be interpreted as an increase in the strength of osseointegration. The purpose of this study was to compare the torque resistance to removal of screw shaped titanium implants having an acid etched (HCl/H2 SO4 ) surface (Osseotite®) with implants having a machined surface. Two custom screw shaped implants, 1 acid etched and the other machined, were placed into the distal femurs of 10 adult New Zealand White rabbits. These implants were 3.25 mm in diameter x 4.00 mm in length without holes, grooves or slots to resist rotation. Following a 2 month healing period, the implants were removed under reverse torque rotation with a digital torque measuring device. Two implants with the machined surface preparation failed to achieve osseointegration. All other implants were found to be anchored to bone. Resistance to torque removal was found to be 4 x greater for the implants with the acid etched surface as compared to the implants with the machined surface. The mean torque values were 20.50 ± 6.59 N cm and 4.95 ± 1.61 N cm for the acid etched and machined surfaces respectively. The results of this study suggest that chemical etching of the titanium implant surface significantly increases the strength of osseointegration as determined by resistance to reverse torque rotation.
Tập 8 Số 6 - Trang 442-447 - 1997
Bone healing at implants with a fluoride‐modified surface: an experimental study in dogs Abstract Objectives: The aim of the present experiment was to study early stages of osseointegration to implants with a fluoride‐modified surface.Material and methods: Six mongrel dogs, about 1‐year old, were used. All mandibular premolars and the first mandibular molars were extracted. Three months later, mucoperiosteal flaps were elevated in one side of the mandible and six sites were identified for implant placement. The control implants (MicroThread™) had a TiOblast surface, while the test implants (OsseoSpeed™) had a fluoride‐modified TiOblast surface. Both types of implants had a similar geometry, a diameter of 3.5 mm and were 8 mm long. Following installation, cover screws were placed and the flaps were adjusted and sutured to cover all implants. Four weeks after the first implant surgery, the installation procedure was repeated in the opposite side of the mandible. Two weeks later, biopsies were obtained and prepared for histological analysis. The void that occurred between the cut bone wall of the recipient site and the macro‐threads of the implant immediately following implant installation was used to study early bone formation.Results: It was demonstrated that the amount of new bone that formed in the voids within the first 2 weeks of healing was larger at fluoride‐modified implants (test) than at TiOblast (control) implants. It was further observed that the amount of bone‐to‐implant contact that had been established after 2 weeks in the macro‐threaded portion of the implant was significantly larger at the test implants than at the controls.Conclusion: It is suggested that the fluoride‐modified implant surface promotes osseointegration in the early phase of healing following implant installation.
Tập 18 Số 2 - Trang 147-152 - 2007