• The Journal of Korean Academy of Prosthodontics
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• v.51 no.1
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• pp.11-19
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• 2013

Purpose: The aim of this study was to evaluate the heat generation in bone in vitro during the guided flapless drilling procedure and the effect of drilling methods on the heat generation. Materials and methods: A model that has missing the first and second mandibular molars bilaterally was used. In group A, classical flap implant surgery was performed. In group B, flapless implant surgery using surgical guide was performed. In group C, flapless implant surgery using surgical guide without up-and-down pumping motion was performed. Temperature was measured with k-type thermocouple and a real-time digital thermometer. The thermocouples were placed at 0.5 mm away from the osteotomy area at the depths of 3 mm and 6 mm. The measured values were evaluated with independent t-test. Results: The mean temperature generated was $27.2^{\circ}C$ ($SD{\pm}2.1^{\circ}C$) and $27.5^{\circ}C$ ($SD{\pm}2.3^{\circ}C$) for groups A and B, respectively. These differences were not statistically significant. In group C, the mean temperature was $37.0^{\circ}C$ ($SD{\pm}3.4^{\circ}C$). There were statistically significant differences between groups B and C with respect to the mean temperature. Conclusion: These findings suggest that guided flapless drilling with up-and-down pumping motion may not significantly increase the bone temperature.

• Journal of Korean Dental Science
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• v.6 no.2
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• pp.50-57
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• 2013

Purpose: Autogenous tooth bone graft is proven to be efficient. We evaluated the bone healing effect and clinical capabilities of autogenous tooth bone materials as a scaffold when growth factor is used together with this material. Materials and Methods: Subjects were those who needed implant placement and bone graft because of missing tooth or alveolar bone defect and who kept their autogenous tooth or needed extraction of other tooth. Group I included autogenous tooth bone graft with growth factor, whereas Group II had only autogenous tooth bone graft. We investigated the bone healing state through computed tomography taken just before surgery and 3 to 4 months after surgery to evaluate the effectiveness of bone graft. Group I had 9 patients, whereas Group II had 5 patients. We compared the pre- and post-operative increase of the Hounsfield unit and bone height by analyzing the computed tomography images. Result: Sinus bone grafts numbered 8 cases, and vertical ridge augmentation was performed together with 3 cases of these. Vertical ridge augmentation was performed in 2 cases, and horizontal ridge augmentation in 1 case alone. Socket graft was done in 3 cases. The post-operative mean value of the Hounsfield unit was 960 in Group I and 836.7 in Group II, but the increase was almost similar, i.e., 636.9 in Group I and 634.7 in Group II on the average. Increase of bone height was 7.6 mm in Group I and 11.1 mm in Group II on the average. This difference was attributable to the fact that most of the cases were sinus bone graft in Group II. Conclusion: In this study, we suggest the possibility of autogenous tooth bone graft materials as a scaffold besides their bone healing ability.

• Journal of Periodontal and Implant Science
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• v.39 no.sup2
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• pp.205-212
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• 2009

Purpose: The aim of this retrospective study was to compare the survival rate of oxidized titanium implants and sandblasted large-grit acid etched implants in soft bone. Methods: 201 oxidized titanium implants were inserted in 84 patients between May 1999 and May 2004. 120 sandblasted large-grit acid etched implants were inserted in 74 patients between December 2000 and May 2004. The patients were followed-up 0${\sim}$5 years in ITI group or 0${\sim}$6 years in BRA group, respectively. The following information was collected from the patient records: age, gender, systemic disease, implant type, number, length and diameter of the implants, their location in the jaws, bone quantity, the number of failed implants, the causes of failure, and advanced surgery for bone augmentation. Results: In the oxidized titanium implants, 8 implants showed early failure, and 1 implant showed late failure, respectively. The cumulative survival rate was 95.48%. In the sandblasted large-grit acid etched implants, 1 implant showed late failure and cumulative survival rate was 99.10%. The cumulative survival rate and the survival rates in the case of the advanced procedure during the implant placement were not significantly different in both groups. Conclusions: Oxidized titanium implants and sandblasted large-grit acid etched implants can be used successfully in soft bone regardless of the surgical methods used during the implant placement. (J Korean Acad Periodontol 2009;39:205-212)

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.41 no.2
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• pp.84-89
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• 2015

We report the eventually successful treatment of a huge bone defect and peri-implantitis following reconstruction of a previously failed intra-mobile cylinder implant system (IMZ) implant site using distraction osteogenesis (DO). In the anterior mandible, two IMZ implants failed and surgical debridement was performed in accordance to the patient's needs. Thereafter, mobility and suppuration were decreased and the patient visited the dental clinic on a regular basis for oral health maintenance. However, the inflammation did not resolve, and the bone destruction around the implants progressed for 4 years. Finally, the implants failed and a severe bone defect remained after implant removal. To reconstruct the bone defects, we attempted bone graft procedures. Titanium mesh was unsuccessfully used to obtain bone volume regeneration. However, DO subsequently was used to obtain sufficient bone volume for implant placement. The new implants were then installed, followed by prosthetic procedures. In conclusion, progression of peri-implantitis could not be arrested despite surgical intervention and repeated maintenance care for 3 years. Reconstruction of the peri-implantitis site was complicated due to its horizontal and vertical bone defects. Lesions caused by implant failure require an aggressive regenerative strategy, such as DO. DO was successful in reconstruction of a peri-implantitis site that was complicated due to horizontal and vertical bone defects.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.4
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• pp.397-404
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• 2019

Bone and soft tissue conditions are important for successful implant treatment. But, the placement itself is also very important. Implants which is installed in the wrong position result in the biological, esthetical and mechanical problems. In order to place an implant in the correct position, the final restoration and diagnostic wax-up should be considered prior to the surgery. If the artificial teeth for the interim denture are directly transferred from the diagnostic wax-up, the operator can try the form of diagnostic wax-up in the mouth. If the surgical template is produced by duplicating the interim denture, the implant can be placed in the planned position. In this case, the polymethyl methacrylate (PMMA) artificial tooth was precisely milled by the digital duplication of diagnostic wax-up. And interim denture was fabricated by using these milled teeth. After the patient adapted for a sufficient period, the implant was placed at the planned position with surgical template produced by duplicating the interim denture. After confirming sufficient osseointegration, the final prostheses were made to reflect the shape of diagnostic wax-up. Through this procedure, the satisfactory functional and esthetic outcome could be acquired.

• Journal of Periodontal and Implant Science
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• v.48 no.6
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• pp.395-404
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• 2018

Purpose: The purpose of this study was to propose a technique for periodontal biotype modification through thickening of the entire facial aspect using a volume-stable collagen matrix and autogenous subepithelial connective tissue graft (CTG) for the treatment of gingival recession. Methods: Four systemically healthy patients showing Miller class I or class II gingival recession in the mandibular incisor area were included in this study. Full-mouth scaling and root planing procedures were performed at least 4 weeks prior to periodontal plastic surgery. A split-thickness flap with a horizontal intrasulcular incision and 2 vertical incisions was used in cases 1-3, and the modified tunnel technique was used in case 4 for coronal advancement of the mucogingival complex. After the exposed root surfaces were debrided thoroughly, double-layered volume-stable collagen matrix was placed on the apical part of the recession and a subepithelial CTG harvested from the palatal area was placed on the coronal part. The amount of root coverage at 3 months postoperatively was evaluated in cases 1-3, and facio-lingual volumetric changes were analyzed in cases 1 and 2. Results: Healing was uneventful in all 4 cases and complete root coverage was shown in cases 1-3. In case 4, reduction of gingival recession was observed at 3 months after surgery. In cases 1 and 2, a comparison of stereolithographic files from the preoperative and postoperative time points demonstrated that the entire facio-lingual volume had increased. Conclusions: The surgical technique suggested herein, using a volume-stable collagen matrix and autogenous subepithelial CTG, may be an effective method for periodontal biotype modification through thickening of the entire facial aspect for the treatment of gingival recession.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.1
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• pp.28-39
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• 2007

The purpose of this study is to evaluate the regenerative capacity of reconstruction in the atrophied posterior maxilla by comparing bone graft procedures and alveolar distraction osteogenesis (ADO) techniques. We performed the autogenous iliac bone graft (AGB group, 5 specimens in 3 patients), and the combination (Mixed group, 3 specimens in 3 patients) of the autogenous and deproteinized bovine bone ($Bio-Oss^{(R)}$, Geistlich Co., Switzerland) as the ratio of 2:1 in the sinus floor elevation procedures. ADO procedures using $TRACK^{(R)}$ (KLS Martin Co., Germany) were also performed to augment vertical alveolar height in atrophied posterior maxilla (ADO group, 5 specimens in 4 patients). Newly generated bone tissues were obtained with the 2.0mm diameter trephine bur (3i Co., USA) during implant fixture installation after 5-7 months. Routine histolomorphological observation, immunodot blot assay for quantitative evaluation, and immunohistochemical staining with antibodies to MMP-1, -9, -10, TIMP-1, -2, and BMP-2, -4 were all carried out. Lamellar bone formation was well shown in all specimens and new bone formations of ADO group increased than those of other procedures. In immunohistochemical staining, the strong expression of BMP-2 was shown in all specimens, and immunodot blot assay showed that bone formation is accompanied by the good induction of factors associated with angiogenesis and appeared more increased amount of osteogenic and angiogenic factors in ADO group. ADO is the most effective technique for new bone formation compared to sinus floor elevation with autogenous or mixed bone graft in the atrophied posterior maxilla. In the quantitative immunodot blot assay, the regenerated bone after ADO showed more increased products of VEGF, BMP-2, PCNA and MMP-1 than those after the other procedures, and these findings were able to be confirmed by immunohistochemical stainings.

• Journal of Korean Dental Science
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• v.2 no.2
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• pp.12-17
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• 2009

Purpose : To determine whether peri-implant crestal bone loss could be affected by systemic disease, primary ISQ value, implantation method (submerged vs. non-submerged), surface treatment, and bone density Materials and methods : Patients who underwent fixture installation from June 24, 2005 to October 23, 2008 at Seoul National University Bundang Hospital were evaluated. A total of 157 patients (male: 52, female: 85) had 346 fixtures installed. Among them, 49 patients had periapical radiographs taken 1 year after prostheses were first set. A total of 97 fixtures were implanted. In particular, 30 fixtures were installed in patients with systemic diseases such as diabetes mellitus, cardiovascular disease, hypertension, and liver disease. The immediate stability of implants was measured with $Osstell^{tm}$. Implant surface treatment was classified into two groups (RBM, Cellnest (Anodized)), and bone density, into four groups (D1~D4). The bone resorption on the mesial and distal areas of fixtures was measured with periapical radiographs using the paralleling technique, and the mean value was calculated. The length determination program in IMPAX (AGFA, Belgium) was used. Results : At least 332 out of 346 (96%) installed GS II implants were successfully osseointegrated 1 year after prostheses were first set. The mean value of the bone resorption of the installed GS II implants was 0.44mm. The minimum value was 0mm, and the maximum value, 2.85mm. There was a statistically significant difference between the implantation methods (submerged, non-submerged) with regard to the amount of alveolar bone loss 1 year after prostheses were first set (p<0.05). Non-submerged implants showed less crestal bone loss. Note, however, that other variables had no correlation with crestal bone loss (p>0.05). Conclusion : There was a statistically significant difference between the 1-stage method and 2-stage method with regard to the amount of alveolar bone loss 1 year after prostheses were first set. Systemic disease, primary ISQ value, surface treatment, and bone density were not associated with alveolar bone loss. Other variables were assumed to have a correlation with alveolar bone loss.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.1
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• pp.71-80
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• 2014

Full-mouth reconstruction of a patient using dental implants is a challenge if there is vertical and horizontal bone resorption. Therefore, it is should be cautious in making the fixed prostheses that restore the function and the esthetics of the gingiva and teeth. In full mouth rehabilitation, CAD/CAM system makes it possible to fabricate restorations with high precision, regardless of span of the restoration. Recently, Palladium-silver (Pd-Ag) alloy which is highly biocompatible and millingable has been developed to compensate for the shortcomings of the titanium or zirconia. This clinical report presents the reconstruction of a maxillary arch with a cement retained implant supported fixed prosthesis using a Pd-Ag alloy generated by CAD/CAM system on eleven osseointegrated implants. The occluding surfaces were made of Pd-Ag alloy, to decrease the risk of chipping or fracture. The prostheses were esthetically pleasing, and no clinical complications have been reported after two years.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.25 no.1
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• pp.15-24
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• 2016

It is considered an implant failure when there is esthetic problems in the anterior area although the prosthesis function normally. In 2003, Dr. Kan et al stated that implant bone level is determined by the adjacent teeth. After that many scholars have studied how can achieve the esthetics result on adjacent teeth bone loss cases. In 2012, Dr. Takino published an article in Quintessence. He summarized previous articles and reclassified the defects from class 1 through 4. Class 1 and 2 depicts a situation where there is no bone loss on adjacent teeth. In Class 3 and 4, interproximal bone loss extends to the adjacent tooth. If one side is involved, it is Class 3. If both sides are involved, it is Class 4. The clue for esthetic implant restoration is whether bone loss extends to adjacent tooth or not. If the bone level of adjacent tooth is sound, we can easily achieve the esthetic but the bone level is not sound, the surgery will be complicated and the esthetic result will be unpredictable. So regenerative surgery for adjacent tooth is necessary for long-term maintenance. But the options and process were so complicated, the purpose of this article is to report the method simplify the surgery and gain a similar outcome.