• Journal of Veterinary Clinics
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• v.20 no.2
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• pp.207-211
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• 2003

This investigation aimed to determine the relative merit of osseointegration in immediate and delayed implantation in the dog mandible using radiography and bone scintigraphy. five adult mongrel dogs with a mean weight of 8.5 kg were used in this investigation. During the entire study period. all dogs were fed with a soft commercial diet and water ad libitum to minimize functional loading of the implant. Twenty titanium alloy systems 4 mm in diameter and 10 mm in length blasted with calcium phosphate were prepared for insertion. The second and third left mandibular premolars in each dog were extracted for the delayed implant insertion. Twelve weeks later, the second and third right mandibular premolars were extracted for the immediate implant insertion. Before the delayed and immediate implantation procedures and 0, 4, 8, and 12 weeks after the insertions, radiography and bone scintigraphy were conducted. Bone scans were obtained using a large field of view gamma camera equipped with a collimator about 3 hours after intravenous injection of Tc-99m-MDP to the dogs. All the dogs were evaluated weekly for inflammation, necrosis, and other of the bone or sort tissue. Significant macroscopic lesions were not detected. Radioisotope scintigraphy with Tc-99m-MDP hat proved to be a reliable method for measuring increased bone activity at specific skeleton tissue sites. In conclusion, osseointegration in peri-implant bone did not differ significantly between the immediate and delayed implant procedures during the experimental period. The immediate implant may be an alternative treatment of implant insertion in animals.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.4
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• pp.477-497
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• 1994

The purpose of this study was to investigate the effect of timing of implant insertion on osseointegration after tooth extraction. Fifteen mongrel dogs, weighing 15kg or more, were used. The lower right 1st, 2nd, 3rd, 4th premolars and 1st molar were extracted under general anesthesia. Implants were inserted at 2, 4, and 8 weeks after extraction of the teeth, being designated as 2-, 4-, and 8-week groups, respectively. Results obtained were as follows. 1. Macroscopically there was neither an infection at the implant site nor an exposure of the implant. 2. Histologically the surrounding bone of the implant was less mature in the 2-week group than in the 4- and 8-week groups. 3. The implant-bone contact ranged from 75 to 82%, with no significant differences among the groups. No increase in the implant-bone contact was found with increasing healing periods from 4 to 12 weeks after implant insertions. 4. The average depth (0.64mm) of the fibrous connective tissue ingrowth in the 2-week group was slightly deeper than those in the 4- (0.51mm) and 8-week (0.53mm) groups at 12 weeks after implant insertion. 5. the implant-bone interfacial bond strengths were 73.05 kgf in the 2-week group, 69.71 kgf in the 4-week group and 73.76 kgf in the 8-week group. No significant difference was noted in pullout force among the groups. The degree of confidence of interfacial bone strength was highest in the 8-week group, followed by the 4- and 2-week groups. These results indicate that at least 4 weeks of healing period will be required before implant is to be inserted following tooth extraction.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.5
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• pp.428-436
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• 2008

For Longevity of implant, considerations of biomechanical and microbiological aspects must be done. Recently, due to the remarkable development of bone grafting procedure. Implant has been implanted into the more favorable sites but peri-implantitis resulted from periodontal bacteria may obscure the long-term prognosis. Although many different modalities have been introduced to treat the failed implant. Implant's surface and irreversible bony destruction around the implant prevents good result. After Er,Cr:YSGG (waterlase) laser using the wave-length of 2780nm has been introduced to dental field, good results have been reported. Because waterlase uses the hydrokinetic force of water. It is excellent device to detoxify the implant surface mechanically without the heat generation and damage to the implant surface. We designed to evaluate waterlase effect on the peri-implantitis has been occurred after implantation. Four beagle dogs were involved. We have made four premolar extraction in each right and left side of the lower jaw and placed two implants in the anterior of the jaw as a control and six implant were placed posterior in each socket after extraction immediately as an experimental group. We tied floss-silk in each implant to make peri-implantitis intentionally. After three months, we explored peri-implant sites on each experimental fixtures. Using waterlase laser irradiation was performed on that implantitis sites under 3W, air 30% and water 20% intensity for 2 minutes. In control group, we repositioned the flap to cover the exposed fixture without any supportive care. Three months later, we sacrificed experimental animals and extracted and preparated bone blocks with Donath and Breuner (982), Donath (988)'s methods and examined under microscope. We have obtained good re-osseointegration around fixtures after treating with waterlaser irradiation. But it was shown fibroosseointegration in the control group.

• The Journal of Advanced Prosthodontics
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• v.7 no.1
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• pp.51-55
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• 2015

PURPOSE. Bone density at implant placement site is a key factor to obtain the primary stability of the fixture, which, in turn, is a prognostic factor for osseointegration and long-term success of an implant supported rehabilitation. Recently, an implant motor with a bone density measurement probe has been introduced. The aim of the present study was to test the objectiveness of the bone densities registered by the implant motor regardless of the operator performing them. MATERIALS AND METHODS. A total of 3704 bone density measurements, performed by means of the implant motor, were registered by 39 operators at different implant sites during routine activity. Bone density measurements were grouped according to their distribution across the jaws. Specifically, four different areas were distinguished: a pre-antral (between teeth from first right maxillary premolar to first left maxillary premolar) and a sub-antral (more distally) zone in the maxilla, and an interforaminal (between and including teeth from first left mandibular premolar to first right mandibular premolar) and a retroforaminal (more distally) zone in the lower one. A statistical comparison was performed to check the inter-operators variability of the collected data. RESULTS. The device produced consistent and operator-independent bone density values at each tooth position, showing a reliable bone-density measurement. CONCLUSION. The implant motor demonstrated to be a helpful tool to properly plan implant placement and loading irrespective of the operator using it.

• Journal of Periodontal and Implant Science
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• v.41 no.5
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• pp.242-247
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• 2011

Purpose: The purpose of this study was to characterize the osseointegration of the fibronectin-coated implant surface. Methods: Sand-blasted, large-grit, acid-etched (SLA) surface implants, with or without a thin calcium phosphate and fibronectin coating, were placed in edentulous mandibles of dogs 8 weeks after extraction. All dogs were sacrificed forhistological and histomorphometric evaluation after 4- and 8-week healing periods. Results: All types of implants were clinically stable without any mobility. Although the bone-to-implant contact and bone density of the SLA implants coated with calcium phosphate (CaP)/fibronectin were lower than the uncoated SLA implants, there were no significant differences between the uncoated SLA surface group and the SLA surface coated with CaP/fibronectin group. Conclusions: Within the limits of this study, SLA surfaces coated with CaP/fibronectin were shown to have comparable bone-to-implant contact and bone density to uncoated SLA surfaces.

• Journal of Periodontal and Implant Science
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• v.43 no.6
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• pp.291-300
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• 2013

Purpose: Calcium phosphate (CaP)-coated implants promote osseointegration and survival rate. The aim of this study was to (1) analyze the dissolution behavior of the residual CaP particles of removed implants and (2) evaluate bone apposition of CaP-coated machined surface implants at the early healing phase. Methods: Mandibular premolars were extracted from five dogs. After eight weeks, the implants were placed according to drilling protocols: a nonmobile implant (NI) group and rotational implant (RI) group. For CaP dissolution behavior analysis, 8 implants were removed after 0, 1, 2, and 4 weeks. The surface morphology and deposition of the coatings were observed. For bone apposition analysis, block sections were obtained after 1-, 2-, and 4-week healing periods and the specimens were analyzed. Results: Calcium and phosphorus were detected in the implants that were removed immediately after insertion, and the other implants were composed mainly of titanium. There were no notable differences between the NI and RI groups in terms of the healing process. The bone-to-implant contact and bone density in the RI group showed a remarkable increase after 2 weeks of healing. Conclusions: It can be speculated that the CaP coating dissolves early in the healing phase and chemically induces early bone formation regardless of the primary stability.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.3
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• pp.319-326
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• 2012

For many years, ceramics have been used in fixed prosthodontics for achieving optimal esthetics. but, they have another use as well. Many studies today show ceramics can be used for biomaterials. In the beginning researchers made a start in the study of aluminium oxide and sapphire for biomaterial. The appearance of Zirconia began a new phase of research. Zirconia was introduced into implantology as an alternative to titanium, because of its white color, good mechanical properties and superior biocompatibility. But it is not easy to surface treatment in comparison with titanium. To overcome the limitation, interconnected porous bodies of zirconia were fabricated by sintering technique. And the technique of coating was developed. Therefore, some zirconia implants are currently available. It is thought that Research of biomaterials as a variety of puposes for the use of zirconia is looking very promising. The purpose of this paper reviews are to evaluation of zirconia as biomaterials.

• The Journal of the Korean dental association
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• v.54 no.7
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• pp.529-540
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• 2016

Objective: The objective of this study was to evaluate the osseointegration of narrow-diameter implant with trapezoid-shape and to evaluate the effect of coronal microthreads on trapezoid-shape narrow-diameter implant. Materials and Methods: The experimental narrow-diameter implants were classified into two groups according to absence or presence of coronal microthreads: trapezoid-shape narrow diameter implant (TN group) and trapezoid-shape narrow-diameter implant with microthreads (TNM group). They were installed alternately in bilateral mandible in three dogs. After 8 weeks, the animals were sacrificed. Resonance frequency analysis, removal torque test, and histometric analysis were performed. Results: Statistically higher implant stability quotient (ISQ) values were observed in TNM group than in TN group at the time of implant installation. However, significant ISQ values difference was not observed between groups at 8 weeks. Both groups showed significantly increased ISQ values at 8 weeks, compared to the time of implant installation. There was no significant difference between groups in removal torque test. Bone-implant contact ratio also showed no significant difference between groups in total and coronal part. Conclusion: Within the limitation of this study, it could be concluded that the trapezoid-shape design on narrow-diameter implant showed successful ossointegration, and the microthreads on coronal part did not result in significant bone-implant contact and biomechanical stability at 8 weeks.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.41 no.5
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• pp.265-269
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• 2015

The purpose of this study was to investigate implant-supported restoration as a technique for restoring missing teeth in patients with aplastic anemia. Recurrent bleeding from wound sites leads to persistent release of iron in the tissue. Excessive iron in tissue is related to clinical findings, including fibrosis, poor wound healing, and high level of angiogenesis, which are possible etiological factors of reduced osseointegration. A 44-year-old female patient with aplastic anemia was treated with multiple endosseous implants throughout the mandible and in the posterior region of the maxilla. After 14 implants were placed, radiological and clinical parameters were assessed during the follow-up period. Marginal bone did not change significantly during the follow-up period. The fine trabecular bone in intimate contact and enclosing the implant fixture was sufficient for successful osseointegration. None of the 14 implants were associated with compilations during the seven-year experimental period. This study suggests that dental implant procedures are a safe and reliable treatment option for restoration of missing dentition in patients with aplastic anemia.

• The Journal of Advanced Prosthodontics
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• v.2 no.4
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• pp.142-147
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• 2010

PURPOSE. One of the major keys to achieve successful osseointegration of the implant is its surface properties. The aim of this study was to investigate the bone response to dental implants with different surface characteristics using the rabbit tibia model. Tricalcium phosphate (TCP) coated, anodic oxidized and turned (control) surfaces were compared. MATERIALS AND METHODS. Seventy two implants were placed in the tibia of eighteen rabbits. Nine rabbits were sacrificed at 3 weeks of healing and the remaining nine were sacrificed at 6 weeks of healing. The bone-to-implant contact (BIC) and the bone volume density (BVD) were assessed by light microscope after 3 and 6 weeks of healing. RESULTS. Statistical analysis showed that no significant differences in the BIC and BVD were observed between the different implant surfaces and the control group at 3 weeks and 6 weeks of healing. Data also suggested that the BVD of all the surfaces showed significant difference at 3 and 6 weeks. CONCLUSION. The present study has showed that osseointegration occurred in all investigated types of surface-treated implants. In the current study all of the threads of the implants were observed to calculate BIC and BVD values (instead of choosing some of the threads from the bone cortex for example), which didn't make BIC or BVD percentage values better than in the control group, therefore the clinical relevance of these results remains to be shown.