Effects of SLA surface treated with NaOH on surface characteristics and response of osteoblast-like cell / 대한치과보철학회지

PURPOSE: The purpose of this study was to evaluate the surface characteristics and response of osteoblast-like cell at SLA surface treated with NaOH. MATERIALS AND METHODS: Three kinds of specimens were fabricated for the experiment groups. Control group was a machined surface, SLA group was a conventionally SLA treated surface, and SLA/NaOH gorup was SLA surface treated with NaOH. To evaluate the surface characteristics, the surface elemental composition (XPS), surface roughness and surface contact angle were evaluated in each group. And the cytotoxicity, cell adhesion, cell proliferation and ATP activity of osteoblast-like cells (MG-63 cells) were compared in each group for evaluatation of the cell responses. Statistical comparisons between groups were carried out via one-way ANOVA using the SPSS software (SPSS Inc., Chicago, USA), and then performed multiple comparisons. The differences were considered statistically significant at P<.05. RESULTS: SLA surface treated with NaOH (SLA / NaOH group) was changed to hydrophilic surface. All groups did not show the cytotoxicity to the MG-63. In cell adhesion studies, SLA / NaOH group showed the higher degree of adhesion than anothers (P<.05), Up to 7 days of incubation, the proliferation was showed the increasing tendency in all groups but SLA / NaOH group showed the highest cell proliferation between the three groups (P<.05). At 7 days of incubation, there was no difference in ALP activities between the three groups, but at 14 days, SLA / NaOH group showed significant increase in ALP activities (P<.05). CONCLUSION: In this study, SLA surface treated with NaOH promoted cell adhesion, proliferation and differentiation. It means that SLA/NaOH group is possible to promote osseointegration of implants.

Analysis of attachment, proliferation and differentiation response of human mesenchymal stem cell to various implant surfaces coated with rhBMP-2 / 대한치과보철학회지

PURPOSE: In this paper we tried to evaluate the most appropriate surface for rhBMP-2 coating among 4 rough titanium surfaces. MATERIALS AND METHODS: We used machined surface as a control group and anodized, RBM and SLA surfaces as test groups. We coated rhBMP-2 on the 4 surfaces and with uncoated surfaces for each case, we cultured human mesenchymal stem cells on all 8 surfaces. 24 hours after we measured the stem cell'attachment with SEM, and on 3rd, 7th, and 14th days, we checked the cell proliferation and differentiation by using MTT and ALP activity assay. And on the 7th day after the culture, we performed RT-PCR assay to determine whether the expression levels of Type I collagen, osteocalcin, osteopontin were changed. RESULTS: We observed with SEM that 4 rhBMP-2 coated surfaces exhibited wider and tighter cell attachment and more cell process spreading than uncoated surfaces. The anodized rhBMP-2 surface caused robustest effects. In MTT assay we could not find any meaningful difference. In ALP assay there was a significant increase (P<.05) in the ALP activity of anodized rhBMP-2 coated surface compared with that of the control (3rd and 14th days) and with that of the RBM rhBMP-2 coated surface (14th day). In RT-PCR assay there was increased expressions in the anodized rhBMP-2 coated surface for osteocalcin, and osteopontin. CONCLUSION: We found that the anodized rhBMP-2 coated surface were most prominent stem cell attachment and differentiation in compared to control and Machined rhBMP-2 coated, RBM rhBMP-2 coated surface.

Retrospective study of the Implantium(R) implant with a SLA surface and internal connection with microthreads / 대한치과보철학회지

STATEMENT OF PROBLEM: Since the introduction of the concept of osseointegration in dental implants, high long-term success rates have been achieved. Though the use of dental implants have increased dramatically, there are few studies on domestic implants with clinical and objective long-term data. PURPOSE: The aim of this retrospective study was to provide long-term data on the Implantium(R) implant, which features a sandblasted and acid-etched surface and internal connection with microthreads. MATERIAL AND METHODS: 106 Implantium(R) implants placed in 38 patients at Yonsei University Hospital were examined to determine the effect of various factors on implant success and marginal bone loss, through clinical and radiographic results during a 6 to 30 month period. RESULTS: 1. Out of a total of 106 implants placed in 38 patients, one fixture was lost, resulting in a 99.1% cumulative survival rate. 2. Among the 96 implants which were observed throughout the study period, the survival rates were 97.0% in the maxilla and 100% in the mandible. The survival rate in the posterior regions was 98.9% and 100% in the anterior regions. 3. The mean bone loss during the first year after prosthesis placement was 0.17 mm, while the mean annual bone loss after the first year was 0.04 mm, which was statistically less than during the first year (P .05), but after the first year, the mean annual bone loss in patients above 50 years was significantly greater (P < .05) compared with patients under 50 years. 5. No significant difference in marginal bone loss was found according to the following factors: gender, jaw, location in the arch, type of implant (submerged or non-submerged), presence of bone grafts, type of prostheses, and type of opposing dentition (P < .05). CONCLUSION: Based on these results, the sole factor influencing marginal bone loss was age, while factors such as gender, jaw, location in the arch, type of implant, presence of bone grafts, type of prostheses and type of opposing dentition had no significant effect on bone loss. In the present study, the success rate of the Implantium(R) implant with a SLA surface and internal connection with microthreads was satisfactory up to a maximum 30 month period, and the marginal bone loss was in accord with the success criteria of dental implants.

Clinical and radiographic evaluation of Neoplant(R) implant with a sandblasted and acid-etched surface and external connection / 대한치과보철학회지

STATEMENT OF PROBLEM: Since the concept of osseointegration in dental implants was introduced by Branemark et al, high long-term success rates have been achieved. Though the use of dental implants have increased dramatically, there are few studies on domestic implants with clinical and objective long-term data. PURPOSE: The aim of this retrospective study was to provide long-term data on the Neoplant(R) implant, which features a sandblasted and acid-etched surface and external connection. MATERIAL AND METHODS: 96 Neoplant(R) implants placed in 25 patients in Yonsei University Hospital were examined to determine the effect of the factors on marginal bone loss, through clinical and radiographic results during 18 to 57 month period. Results: 1. Out of a total of 96 implants placed in 25 patients, two fixtures were lost, resulting in 97.9% of cumulative survival rate. 2. Throughout the study period, the survival rates were 96.8% in the maxilla and 98.5% in the mandible. The survival rates were 97.6% in the posterior regions and 100% in the anterior regions. 3. The mean bone loss for the first year after prosthesis placement and the mean annual bone loss after the first year for men were significantly higher than that of women (P<0.05). 4. The group of partial edentulism with no posterior teeth distal to the implant prosthesis showed significantly more bone loss compared to the group of partial edentulism with presence of posterior teeth distal to the implant prosthesis in terms of mean bone loss for the first year and after the first year (P<0.05). 5. The mean annual bone loss after the first year was more pronounced in posterior regions compared to anterior regions (P<0.05). 6. No significant difference in marginal bone loss was found in the following factors: jaws, type of prostheses, type of opposing dentition, and submerged /non-submerged implants (P<0.05). CONCLUSION: On the basis of these results, the factors influencing marginal bone loss were gender, type of edentulism, and location in the arch, while the factors such as arch, type of prostheses, type of opposing dentition, submerged / non- submerged implants had no significant effect on bone loss. In the present study, the cumulative survival rate of the Neoplant(R) implant with a sandblasted and acid-etched surface was 97.9% up to a maximum 57-month period. Further long-term investigations for this type of implant system and evaluation of other various domestic implant systems are needed in future studies.

Microstructural Change of Porous Surface Implant conditioned with Tetracycline-hydrochloride / 대한치주과학회지

Mechanical and chemical methods are the two ways to treat the implant surfaces. By using mechanical method, it is difficult to eliminate bacteria and by-products from the rough implant surface and it can also cause the structural change to the implant surface. Therefore, chemical method is widely used in order to preserve and detoxicate the implant surface more effectively. The purpose of this study is to evaluate the effect of tetracylcline-hydrochloride(TC-HCl) on the change of implant surface microstructure according to application time. Implants with pure titanium machined surface, SLA surface and porous surface were used in this study. Implant surface was rubbed with sponge soaked in 50mg/ml TC-HCl solution for 1/2 min., 1 min., 1 1/2 min., 2 min., and 2 1/2min. respectively in the test group and with no treatment in the control group. Then, specimens were processed for scanning electron microscopic observation. 1. Both test and control group showed a few shallow grooves and ridges in pure titanium machined surface implants. There were not significant differences between two groups. 2. In the SLA surfaces, the control specimen showed that the macro roughness was achieved by large-grit sandblasting. Subsequently, the acid-etching process created the micro roughness, which thus was superimposed on the macro roughness. Irrespective of the application time of 50mg/ml TC-HCl solution, in general, test specimens were similar to control. 3. In the porous surfaces, the control specimen showed spherical particles of titanium alloy and its surface have a few shallow ridges. The roughness of surfaces conditioned with tetracycline-HCl was lessened and seen crater-like irregular surfaces relative to the application time. In conclusion, pure titanium machined surfaces and SLA surfaces weren't changed irrespective of the application time of tetracycline-HCl solution. But the porous surfaces conditioned with tetracycline-HCl solution began to be slightly changed from 2 min. This results are expected to be applied to the regenerative procedures for peri-implantitis treatment.

Clinical, histologic, and histometric evaluation of implants with microthreaded crest module and SLA surface / 대한치주과학회지

BACKGROUND: Crestal bone loss known as saucerization is a frequently observed phenomenon. Recent studies have shown that implants with micothreaded crest module reduced the force concentration in the crestal region thus resulting in no or reduced crestal bone loss. This study presents a clinical, histologic, and histometric evaluation of implants with microthreaded crest module and SLA surface. METHODS: The implants were placed in the mandible of 5 beagle dogs weighing 10-15kg. Four premolars were bilaterally extracted 8 weeks prior to implant placement. Mucoperiosteal flap was elevated and drilling with increasing diameter was performed under saline irrigation. After countersinking 2 implants were placed in each side resulting in 4 implants per dog. Healing period of 8 weeks was allowed before sacrificing the animals. Histologic preparation was performed for histologic and histometric analysis. Bone to implant contact as well as percentage of bone area inside threads were measured. T-test was used for statistical analysis with pvalue p<0.05. RESULTS: 1. Healing was uneventful without any cover screw exposure. New bone formation around the implants was observed without any inflammatory infiltration. 2. Bone to implant contact in the microthread and thread were 43.90 +/- 20.30 %, and 53.19 +/- 20.97 % respectively. The overall bone to implant contact was 48.54 +/- 20.95 %. 3. Percentage of bone area inside threads were 54.43 +/- 10.39 %, and 38.44 +/- 16.44 % for the microthread and thread respectively. There was statistically significant difference(p<0.05). The overall percentage of bone area inside threads was 46.67 +/- 15.68 %.

Histologic findings of three-wall intrabony defects around dental implants using different grafting materials in beagle dogs / 대한치주과학회지

No abstract available.

Scanning Electron Microscopic Study of the Effect of Tetracycline-HCl on the Change of Implant Surface Microstructure according to Application Time / 대한치주과학회지

The present study was performed to evaluate the effect of tetracycline - HCl on the change of implant surface microstructure according to application time. Implants with pure titanium machined surface, SLA surface and TiO2blasted surface were used. Implant surface was rubbed with 50mg/ml tetracycline - HCl solution for 1/2 min., 1 min., 1 1/2 min., 2 min., and 3min. respectively in the test group and with no conditioning in the control group. Then, the specimens were processed for scanning electron microscopic observation. The following results were obtained. 1. In the pure titanium machined surfaces, the control specimen showed a more or less rough machined surface composed of alternating positive and negative lines corresponding to grooves and ridges. After treatment, machining line was more pronounced for the control specimens. but in general, test specimens were similar to control. 2. In the SLA surfaces, the control specimen showed that the macro roughness was achieved by large-grit sandblasting. subsequently, the acid-etching process created the micro roughness, which thus was superimposed on the macro roughness. 3. In the SLA surfaces, irrespective of the application time of 50mg/ml tetracycline - HCl solution , in general, test specimens were similar to control. 4. In the TiO2blasted surfaces the control specimen showed the rough surface with small pits. The irregularity of the TiO2blasted surfaces with 50mg/ml tetracycline - HCl solution was lessened and the flattened areas were wider relative to the application time of tetracycline - HCl solution. In conclusion, pure titanium machined surfaces and SLA surfaces weren't changed irrespective of the application time of tetracycline - HCl solution. And the TiO2blasted surfaces conditioned with tetracycline - HCl solution began to be changed from 1 1/2 min. This results are expected to be applied to the regenerative procedures for peri-implantitis treatment.