• Journal of Periodontal and Implant Science
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• v.37 no.4
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• pp.681-690
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• 2007

Mini implants had been used provisionally for the healing period of implants in the beginning. But it becomes used for the on-going purpose, because it is simple to use, economic and especially suitable for the overdenture. But there is few studies about the stability of mini implants, that is most important factor for the on-going purpose, and particularly the implant parameters affecting the initial stability. The purpose of this study was to evaluate the stress and the strain distribution pattern of immediate-loaded screw type orthodontic mini-implant and the parameters affecting the initial stability of immediate-loaded mini-implant. Two dimensional finite element models were made and contact non-linear finite element analysis was performed. The magnitude and distribution of Von Mises stresses were evaluated. The obtained results were as follows: 1. The stress was concentrated on the thread tip of an implant in the cortical bone. 2. The direction of load is the most important factor for the stress distribution in cortical bone. 3. The diameter of an implant is the most important factor for the stress distribution in the trabecular bone. In conclusion, if the horizontal load vector is successfully controlled, mini-implants, which diameter is under 3mm, can be used for the on-going purpose.

• Journal of Periodontal and Implant Science
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• v.49 no.3
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• pp.171-184
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• 2019

Purpose: To evaluate the effects of intra-alveolar socket grafting, subepithelial connective tissue grafts, and individualized abutments on peri-implant hard and soft tissue outcomes following immediate implant placement. Methods: This randomized experimental study employed 5 mongrel dogs, with 4 sites per dog (total of 20 sites). The mesial roots of P3 and P4 were extracted in each hemimandible and immediate dental implants were placed. Each site was randomly assigned to 1 of 4 different treatment groups: standardized healing abutment (control group), alloplastic bone substitute material (BSS) + standardized healing abutment (SA group), BSS + individualized healing abutment (IA group), and BSS + individualized healing abutment + a subepithelial connective tissue graft (IAG group). Clinical, histological, and profilometric analyses were performed. The intergroup differences were calculated using the Bonferroni test, setting statistical significance at P<0.05. Results: Clinically, the control and SA groups demonstrated a coronal shift in the buccal height of the mucosa ($0.88{\pm}0.48mm$ and $0.37{\pm}1.1mm$, respectively). The IA and IAG groups exhibited an apical shift of the mucosa ($-0.7{\pm}1.15mm$ and $-1.1{\pm}0.96mm$, respectively). Histologically, the SA and control groups demonstrated marginal mucosa heights of $4.1{\pm}0.28mm$ and $4.0{\pm}0.53mm$ relative to the implant shoulder, respectively. The IA and IAG groups, in contrast, only showed a height of 2.6mm. In addition, the height of the mucosa in relation to the most coronal buccal bone crest or bone substitute particles was not significantly different among the groups. Volumetrically, the IA group ($-0.73{\pm}0.46mm$) lost less volume on the buccal side than the control ($-0.93{\pm}0.44mm$), SA ($-0.97{\pm}0.73mm$), and IAG ($-0.88{\pm}0.45mm$) groups. Conclusions: The control group demonstrated the most favorable change of height of the margo mucosae and the largest dimensions of the peri-implant soft tissues. However, the addition of a bone substitute material and an individualized healing abutment resulted in slightly better preservation of the peri-implant soft tissue contour.

• The Journal of Advanced Prosthodontics
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• v.3 no.1
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• pp.47-50
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• 2011

Despite the greater retention and low maintenance of bar attachment system, the longer clinical time and increased number of visits were the assignments to overcome in bar attachment system. This case report describes SFI-Bar$^{(R)}$ (Cendres et Me$\'{e}$taux, Biel/Bienne, Switzerland) to be solve those problems. A 65-year-old female, who had severely absorbed mandible, hoped to wear a stable mandibular denture without pain. As soon as two implants were placed on mandible, a tube bar was connected to two adaptors connected to each implant. The length of the tube bar was adjusted considering inter implant distance, and reconnected to the adaptors. Finally a female part was seated beneath the denture. This case report showed that a satisfactory clinical result was achieved by delivering bar overdenture immediately after implant placement without laboratory procedure.

• Journal of Power System Engineering
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• v.18 no.5
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• pp.60-65
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• 2014

This research examined an immediate loading capable of providing a masticatory function and financial affordability while satisfying every requirement of a useful immediate loading. In this research, numerical value analysis was performed on couple-type posterior teeth implants developed by making up for the problems of extant implants. As a result of examining the effects of external impacts on extant implants and their deformation, relatively lager deformations separated from a molar were found concerning molar deformation implant with the maximum deformation level being approximately 1.657mm. In this research, the improved implant showed much improvement in terms of impact analysis in its deformation dispersion status after unloading the impulsive load from a punch. As for the case of hepf, about 1.657mm occurred but the improved model showed about 0.9217mm, exhibiting 55.6% advancement.

• Journal of Periodontal and Implant Science
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• v.46 no.4
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• pp.234-243
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• 2016

Purpose: Immediate loading of dental implants has been proved to be feasible in partially edentulous jaws. The purpose of this retrospective investigation was to assess the feasibility of immediately loading dental implants in fully edentulous jaws. Methods: A total of 24 patients aged between 53 and 89 years received a total of 154 implants in their edentulous maxillae or mandibles. Among the implants, 45 were set in fresh extracted sockets and 109 in consolidated alveolar bones. The implants were provisionally managed with chair-side made provisional resin bridges and exposed to immediate loading. Implants were followed up for 1-8 years, including radiographic imaging. Marginal bone levels were evaluated based on radiographic imaging. Results: A total of 148 out of the 154 implants survived over the follow-up period of 1 to 8 years, giving a survival rate of 96%. The time or region of the implantation, the pre-implant augmentation, and the length and diameter of the implants had no statistically significant influence on the survival or the success rate. The marginal bone level remained stable with only minimal loss of 0.3 mm after 60 months of loading. Conclusions: Within the limitations of this study, immediate loading is feasible for dental implants in edentulous jaws.

• The Journal of Advanced Prosthodontics
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• v.7 no.2
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• pp.160-165
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• 2015

PURPOSE. In this study, a temporal abutment fixation screw, designed to fracture in a controlled way upon application of an occlusal force sufficient to produce critical micromotion was developed. The purpose of the screw was to protect the osseointegration of immediate loaded single implants. MATERIALS AND METHODS. Seven different screw prototypes were examined by fixing titanium abutments to 112 Mozo-Grau external hexagon implants (MG Osseous$^{(R)}$; Mozo-Grau, S.A., Valladolid, Spain). Fracture strength was tested at $30^{\circ}$ in two subgroups per screw: one under dynamic loading and the other without prior dynamic loading. Dynamic loading was performed in a single-axis chewing simulator using 150,000 load cycles at 50 N. After normal distribution of obtained data was verified by Kolmogorov-Smirnov test, fracture resistance between samples submitted and not submitted to dynamic loading was compared by the use of Student's t-test. Comparison of fracture resistance among different screw designs was performed by the use of one-way analysis of variance. Confidence interval was set at 95%. RESULTS. Fractures occurred in all screws, allowing easy retrieval. Screw Prototypes 2, 5 and 6 failed during dynamic loading and exhibited statistically significant differences from the other prototypes. CONCLUSION. Prototypes 2, 5 and 6 may offer a useful protective mechanism during occlusal overload in immediate loaded implants.

• 대한치과보철학회:학술대회논문집
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• 1998.05a
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• pp.63-63
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• 1998

• 대한치과보철학회:학술대회논문집
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• 2002.11a
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• pp.50-50
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• 2002

• 대한치주과학회:학술대회논문집
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• 2002.11a
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• pp.9-10
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• 2002

• 대한치주과학회:학술대회논문집
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• 2003.05a
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• pp.19-20
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• 2003