• Journal of Periodontal and Implant Science
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• 제45권3호
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• pp.94-100
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• 2015

Purpose: The aim of this study was to investigate the combined effects of physical and chemical surface factors on in vivo bone responses by comparing chemically modified hydrophilic sandblasted, large-grit, acid-etched (modSLA) and anodically oxidized hydrophobic implant surfaces. Methods: Five modSLA implants and five anodized implants were inserted into the tibiae of five New Zealand white rabbits (one implant for each tibia). The characteristics of each surface were determined using field emission scanning electron microscopy, energy dispersive spectroscopy, and confocal laser scanning microscopy before the installation. The experimental animals were sacrificed after 1 week of healing and histologic slides were prepared from the implant-tibial bone blocks removed from the animals. Histomorphometric analyses were performed on the light microscopic images, and bone-to-implant contact (BIC) and bone area (BA) ratios were measured. Nonparametric comparison tests were applied to find any significant differences (P<0.05) between the modSLA and anodized surfaces. Results: The roughness of the anodized surface was $1.22{\pm}0.17{\mu}m$ in Sa, which was within the optimal range of $1.0-2.0{\mu}m$ for a bone response. The modSLA surface was significantly rougher at $2.53{\pm}0.07{\mu}m$ in Sa. However, the modSLA implant had significantly higher BIC than the anodized implant (P=0.02). Furthermore, BA ratios did not significantly differ between the two implants, although the anodized implant had a higher mean value of BA (P>0.05). Conclusions: Within the limitations of this study, the hydrophilicity of the modSLA surface may have a stronger effect on in vivo bone healing than optimal surface roughness and surface chemistry of the anodized surface.

• 대한치과보철학회지
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• 제48권3호
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• pp.209-214
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• 2010

연구 목적: 본 연구의 목적은 골 유착된 임플란트에 인위적 비틀림을 가한 후 골 유착이 다시 일어나는지, 혹은 일어나지 않는지, 일어난다면 이전의 골유착보다 강화되는지, 약화되는지에 대해 알아보기 위함이다. 연구 재료 및 방법:상업적으로 순수한 티타늄 (commercial pure titanium 99%)으로 직경 3.75 mm, 길이 4 mm의 표면처리 없는 실험용 임플란트를 제작하였다. 3.0 kg이상의 뉴질랜드산 흰색 암컷 토끼 7마리의 좌우 경골에 제작한 임플란트를 2개씩 식립 후, 6주의 골유착 유도 기간 부여 후 비틀림 제거력을 측정한 경우를 I군으로, 다시 임플란트 고정체를 재위치시키고 봉합하여 4주간의 치유기간을 더 두고 측정한 경우를 II군으로 분류하였다. 광학현미경을 이용한 조직 형태학적 분석을 위하여, 1차 비틀림 제거력 측정 직후 1마리의 토끼를 희생시키고, 2차 비틀림 제거력 측정 직후 2마리의 토끼를 희생시켜 각각 4개, 7개의 시편을 제작하여, 광학현미경 (${\times}20$) 분석에서 골-임플란트 접촉 (Bone-Implant contact, BIC, %)비율과 치밀골 부위에 위치하는 임플란트의 나사산 수를 측정하여 CBa (Bone area in the cortical passage)비율을 측정하였다. 비틀림 제거력과 BIC및 CBa비율에서의 I군과 II군의 통계적 유의성 ($\alpha$=.05)을 평가하였다. 결과: 비틀림 제거력 측정에서 I군은 $10.8{\pm}3.6$ NCm로 측정되었으며, II군은 $20.2{\pm}9.7$ NCm로 측정되었으며, I군보다II군의 비틀림 제거력이 평균 98.1% 증가되었다 (P<.05). 조직 형태학적 분석에서 BIC와 CBa 비율은 I군과 II군 사이에 통계적 유의성을 나타내지 않았고 (P>.05), RT/BIC와 RT/CBa 값은 I군과 II군 사이에 통계적 유의성을 나타냈다 (P<.05). 결론: 임플란트 고정체에 의원성 비틀림 동요가 발생한 경우에 초기 골유착을 얻기 위해 필요로 했던 치유기간보다 짧은 기간 내에 이전보다 견고한 골유착을 얻을 수 있을 것으로 생각된다.

• The Journal of Advanced Prosthodontics
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• 제1권1호
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• pp.10-18
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• 2009

STATEMENT OF PROBLEM. Despite an improved bone reactions of Mg-incorporated implants in the animals, little yet has been carried out by the experimental investigations in functional loading conditions. PURPOSE. This study investigated the clinical and histologic parameters of osseointegrated Mg-incorporated implants in early loading conditions. MATERIAL AND METHODS. A total of 36 solid screw implants(diameter 3.75 mm, length 10 mm) were placed in the mandibles of 6 beagle dogs. Test groups included 18 Mg-incorporated implants. Turned titanium implants served as control. Gold crowns were inserted 4 weeks after implant placement and the dogs were immediately put on a food diet. Implants were observed for 10 weeks after loading. Radiographic assessments and stability tests were performed at the time of fixture installation, $2^{nd}$ stage surgery, 4 weeks after loading, and 10 weeks after loading. Histological observations and morphometrical measurements were also performed. RESULTS. Of 36 implants, 33 displayed no discernible mobility, corresponding to successful clinical function. There was no statistically significant difference between test implants and controls in marginal bone levels(P=.46) and RFA values. The mean BIC % in the Mg-implants was $54.5{\pm}8.4%$. The mean BIC % in the turned implant was $45.3{\pm}12.2%$. These differences between the Mg-implant and control implant were statistically significant(P=.005). CONCLUSIONS. The anodized, Mg-incorporated implant demonstrated significantly more bone-to-implant contact(BIC) in early loading conditions. CLINICAL IMPLICATIONS. The results of this study in beagle dogs suggest the possibility of achieving predictable stability of early loaded free-standing dental implants with Mg-incorporated surface.

• 대한치과교정학회지
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• 제38권6호
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• pp.416-426
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• 2008

본 연구는 비글견에 식립된 sandblasted, large grit and acid-etched (SLA) 표면처리된 교정용 마이크로임플랜트와 평활면 마이크로임플랜트에 교정력을 가한 후 시간 경과에 따른 동요도와 골접촉률의 차이를 규명하기 위해 시행되었다. 비글 성견 네 마리를 이용하여 상, 하악 협측과 구개측 골에 대해 SLA 표면처리된 표면처리군 48개, 평활면의 비처리군 48개의 마이크로임 플랜트 96개를 식립하고 2주의 치유기간 후 교정력(150 - 200 g)을 지속적 으로 가했으며 식립 4주 후에 두 마리를 희생시키고, 12주 후에 나머지 2마리를 희생시켰다. 표면처리군과 비처리군 간의 마이크로 임플랜트의 동요도와 골과 임플랜트 간 접촉률을 조직학적인 측면에서 측정 비교하여 다음과 같은 결과를 얻었다. 상악 협측과 구개측에서는 표면처리군과 미처리군의 동요도에서 유의성 있는 차이가 없었으나 하악협측에서는 표면 처리군이 유의하게 안정적인 동요도를 보였다. 마이크로임플랜트와 인접골 간 접촉률은 상악 협측에서는 4주와 12주 모두 표면처리군과 미처리군 간에 유의 한 차이가 없었으나 하악 협측과 구개측의 경우 4주와 12주 모두 표면처리군이 비처리군에 비해 유의하게 높은 접촉률을 보였다. 표면처리군은 비처리군에 비해 임플랜트 주변에서 활발한 골개조가 관찰되었으며 모든 군에서 이물반응은 관찰되지 않았다. 본 연구를 통해 SLA 표면처리된 마이크로임플랜트는 평활면 마이크로임플랜트에 비하여 식립 초기에는 식립 부위에 따라 유의하게 높은 인접골 간 접촉률과 동요도의 안정성을 보임으로써 다양한 크기와 방향의 교정력의 적용이 가능할 것이라 생각한다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권6호
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• pp.461-468
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• 2009

Purpose: Platelet derived growth factor(PDGF)-BB and bone morphogenetic protein(BMP)-2 are well-known representative growth factors. The purposes of this study were to investigate the effect of rhPDGFBB and rhBMP-2 on osseointegration of titanium implants at periimplant bone defects grafted with hydroxyapatite and to evaluate the feasibility of imaging bone structures around screw-type titanium implant with micro-CT. Materials and Methods: The first molar and all premolars in the mandible region of four beagle dogs were extracted. Following a healing period of 4 months, three $8{\times}8{\times}6mm$-sized bony defects were formed and screw-type titanium implants were placed with hydroxyapatite(HA) block and growth factors; Control group, PDGF group and BMP group. Two months post-implantation, the mandible was harvested. Bone volume(BV), bone-to-implant contact(BIC) and bone mineral density(BMD) were analyzed with micro-CT and histology. Results: According to micro-CT analysis, BV and BMD measures of PDGF and BMP group were significantly higher than control group(BV; PDGF group: $p{\fallingdotseq}0.011$, BMP group: $p{\fallingdotseq}0.006$/BMD; PDGF group: $p{\fallingdotseq}0.020$, BMP group: $p{\fallingdotseq}0.011$) and BIC measures of BMP group were significantly higher than PDGF group($p{\fallingdotseq}0.015$). In histologic evaluation, BIC measures of BMP group was significantly higher than PDGF group($p{\fallingdotseq}0.048$). The values of BV in histologic sections were higher than in micro-CT images and the values of BIC in micro-CT images were higher than in histologic sections. Conclusion: The findings of this experimental study indicates that the use of rhPDGF-BB and rhBMP-2 can increase new bone formation in a large bony defect around titanium implant, and rhBMP-2 is more effective than rhPDGF-BB. Micro-CT can be considered useful for assessment as a rapid and nondestructive method for 3-dimensional measurement of bone healing around implants. Further study is necessary, however, to remove metal artifacts around titanium implant and to standardize the method.

• Journal of Periodontal and Implant Science
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• 제51권5호
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• pp.352-363
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• 2021

Purpose: Some systemic conditions, especially diabetes mellitus (DM), adversely affect dental implant success. This study aimed to investigate the effects of ibuprofen-loaded TiO₂ nanotube (ILTN) dental implants in alloxan-induced diabetic rabbits. Methods: Twenty-six New Zealand white rabbits were treated with alloxan monohydrate to induce DM. At 2 weeks following DM induction, 3 types of implants (sandblasted, large-grit, and acid-etched [SLA], ILTN, and machined) were placed into the proximal tibia in the 10 rabbits that survived following DM induction. Each type of implant was fitted randomly in 1 of the holes (round-robin method). The animals were administered alizarin (at 3 weeks) and calcein (at 6 weeks) as fluorescent bone markers, and were sacrificed at 8 weeks for radiographic and histomorphometric analyses. Results: TiO₂ nanotube arrays of ~70 nm in diameter and ~17 ㎛ in thickness were obtained, and ibuprofen was loaded into the TiO₂ nanotube arrays. A total of 26 rabbits were treated with alloxan monohydrate and only 10 rabbits survived. The 10 surviving rabbits showed a blood glucose level of 300 mg/dL or higher, and the implants were placed in these diabetic rabbits. The implant stability quotient (ISQ) and bone-to-implant contact (BIC) values were significantly higher in the ILTN group (ISQ: 61.8, BIC: 41.3%) and SLA group (ISQ: 62.6, BIC: 46.3%) than in the machined group (ISQ: 53.4, BIC: 20.2%), but the difference in the BIC percentage between the SLA and ILTN groups was not statistically significant (P=0.628). However, the bone area percentage was significantly higher in the ILTN group (78.0%) than in the SLA group (52.1%; P=0.000). Conclusions: The: ILTN dental implants showed better stability (ISQ) and BIC than the machined implants; however, these values were similar to the commercially used SLA implants in the 2-week diabetic rabbit model.

• The Journal of Advanced Prosthodontics
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• 제6권1호
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• pp.14-21
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• 2014

PURPOSE. The purpose of this study was to evaluate bone response to anodized titanium implants coated with the extract of black cohosh, Asarum Sieboldii, and pharbitis semen. MATERIALS AND METHODS. Forty anodized titanium implants were prepared as follows: group 1 was for control; group 2 were implants soaked in a solution containing triterpenoids extracted from black cohosh for 24 hours; group 3 were implants soaked in a solution containing extracts of black cohosh and Asarum Sieboldii for 24 hours; group 4 were implants soaked in a solution containing extracts of pharbitis semen for 24 hours. The implants from these groups were randomly and surgically implanted into the tibiae of ten rabbits. After 1, 2, and 4 weeks of healing, the nondecalcified ground sections were subjected to histological observation, and the percentage of bone-to-implant contact (BIC%) was calculated. RESULTS. All groups exhibited good bone healing with the bone tissue in direct contact with the surface of the implant. Group 2 ($52.44{\pm}10.98$, $25.54{\pm}5.56$) showed a significantly greater BIC% compared to that of group 3 ($45.34{\pm}5.00$, $22.24{\pm}2.20$) with respect to the four consecutive threads and total length, respectively. The BIC% of group 1 ($25.22{\pm}6.00$) was significantly greater than that of group 3 ($22.24{\pm}2.20$) only for total length. CONCLUSION. This study did not show any remarkable effects of the extract of black coshosh and the other natural products on osseointegration of anodized titanium implants as coating agents. Further studies about the application method of the natural products on to the surface of implants are required.

• Journal of Yeungnam Medical Science
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• 제36권1호
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• pp.43-49
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• 2019

Background: In the osseointegration of dental implants, the implant surface properties have been reported to be some of the most important critical factors. The effect of implant's surfaces created by resorbable blast media (RBM) followed by laser ablation on bone tissue reactions was examined using the removal torque test and histomorphometric analysis. Methods: Two types of dental implants, RBM-laser implants (experimental group) and RBM implants (control group) (CSM implant system, Daegu, Korea; L=6 mm, diameter=3.75 mm) were placed into the right and left distal femoral metaphysis of 17 adult rabbits. Six weeks after placement, removal torque was measured and histomorphometric analysis was performed. Results: The mean removal torque was $24.0{\pm}10.2Ncm$ and $46.6{\pm}16.4Ncm$ for the control and test specimens, respectively. The experimental RBM-laser implants had significantly higher removal torque values than the control RBM implants (p=0.013). The mean values of total and cortical bone to implant contact (BIC) were respectively $46.3{\pm}10.8%$ and $65.3{\pm}12.5%$ for the experimental group, and $41.9{\pm}18.5%$ and $57.6{\pm}10.6%$ for the control group. The experimental RBM-laser implants showed a higher degree of total and cortical BIC compared with RBM implants, but there was no statistical significance (p=0.482, 0.225). Conclusion: The removal torque and BIC of the test group were higher than those of the control group. In this study, the surface treatment created by RBM treatment followed by laser ablation appears to have a potential in improving bone tissue reactions of dental implants.

• Journal of Periodontal and Implant Science
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• 제40권5호
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• pp.244-248
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• 2010

Purpose: The purpose of this study was to radiographically evaluate marginal bony changes in relation to different vertical positions of dental implants. Methods: Two hundred implants placed in 107 patients were examined. The implants were classified by the vertical positions of the fixture-abutment connection (microgap): 'bone level,' 'above bone level,' or 'below bone level.' Marginal bone levels were examined in the radiographs taken immediately after fixture insertion, immediately after second-stage surgery, 6 months after prosthesis insertion, and 1 year after prosthesis insertion. Radiographic evaluation was carried out by measuring the distance between the microgap and the most coronal bone-to-implant contact (BIC). Results: Immediately after fixture insertion, the distance between the microgap and most coronal BIC was $0.06{\pm}0.68\;mm$; at second surgery, $0.43{\pm}0.83\;mm$; 6 months after loading, $1.36{\pm}0.56\;mm$; and 1 year after loading, $1.53{\pm}0.51\;mm$ ($mean{\pm}SD$). All bony changes were statistically significant but the difference between the second surgery and the 6-month loading was greater than between other periods. In the 'below bone level' group, the marginal bony change between fixture insertion and 1 year after loading was about 2.25 mm, and in the 'bone level' group, 1.47 mm, and in 'above bone level' group, 0.89 mm. Therefore, the marginal bony change was smaller than other groups in the 'above bone level' group and larger than other groups in the 'below bone level' group. Conclusions: Our results demonstrated that marginal bony changes occur during the early phase of healing after implant placement. These changes are dependent on the vertical positions of implants.

• Journal of Periodontal and Implant Science
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• 제42권4호
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• pp.136-143
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• 2012

Purpose: The osseointegration around titanium mini-implants installed in macroporous biphasic calcium phosphate (MBCP) blocks was evaluated after incubation with recombinant human bone morphogenetic protein-2 (rhBMP-2) in an ectopic subcutaneous rat model. Methods: Mini-implants (${\varphi}1.8{\times}12$ mm) were installed in MBCP blocks (bMBCPs, $4{\times}5{\times}15$ mm) loaded with rhBMP-2 at 0.1 mg/mL, and then implanted for 8 weeks into subcutaneous pockets of male Sprague-Dawley rats (n=10). A histomorphometric analysis was performed, and the bone-to-implant contact (BIC) and bone density were evaluated. Results: Significant osteoinductive activity was induced in the rhBMP-2/bMBCP group. The percentage of BIC was $41.23{\pm}4.13%$ (mean${\pm}$standard deviation), while bone density was $33.47{\pm}5.73%$. In contrast, no bone formation was observed in the bMBCP only group. Conclusions: This model represents a more standardized tool for analyzing osseointegration and bone healing along the implant surface and in bMBCPs that excludes various healing factors derived from selected animals and defect models.