• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.4
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• pp.371-392
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• 2011

The purpose of this study was to comparatively analyze the stress distribution according to the inclinations of abutments and angulations of the implant fixtures under occlusal loading force. Three study models with straight and $15^{\circ}$ and $25^{\circ}$-angled abutments were prepared following the insertion of Implants parallel to the long axis of the tooth. Additional two experimental models were fabricated with $15^{\circ}$ and $25^{\circ}$ fixture inclinations. Using ANSYS 11, a finite element analysis program, the magnitudes of stress distribution were analyzed. The magnitude of stress under loading was lowest when the load was applied vertically onto the axis of implant. And the magnitude of stress under compound(vertical+oblique) loading was increased as the inclination of implant abutment and fixture was increase. But, the distribution of stress was different as the loading conditions, because of the horizontal offset. As the offset between the axis of loading and the central axis of the implant increased, the stress was increased.

• Journal of Periodontal and Implant Science
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• v.42 no.3
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• pp.105-109
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• 2012

Purpose: Soft tissue recessions frequently cause esthetic disharmony and dissatisfaction. Compared with soft tissue coverage around a tooth, the coverage of an implant site is obviously unpredictable. Particularly in the cases of thin mucosa, a significant greater amount of recession takes place compared to thick mucosa. To overcome this problem, this case report demonstrates a two-step mucosal dehiscence coverage technique for an endosseous implant. Methods: A 33-year-old female visited us with the chief complaint of dissatisfaction with the esthetics of an exposed implant in the maxillary left cental incisor region. A partial-thickness pouch was constructed around the dehiscence. A subepithelial connective tissue graft was positioned in the apical site of the implant and covered by a mucosal flap with normal tension. At 12 months after surgery, the recipient site was partially covered by keratinized mucosa. However, the buccal interdental papilla between implant on maxillary left central incisor region and adjacent lateral incisor was concave in shape. To resolve the mucosal recession after the first graft, a second graft was performed with the same technique. Results: An esthetically satisfactory result was achieved and the marginal soft tissue level was stable 9 months after the second graft. Conclusions: The second graft was able to resolve the mucosal recession after first graft. This two-step approach has the potential to improve the certainty of esthetic results.

• Journal of Periodontal and Implant Science
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• v.46 no.3
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• pp.136-151
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• 2016

Peri-implant disease is a serious problem that plagues today's dentistry, both in terms of therapy and epidemiology. With the expansion of the practice of implantology and an increasing number of implants placed annually, the frequency of peri-implant disease has greatly expanded. Its clinical manifestations, in the absence of a globally established classification, are peri-implant mucositis and peri-implantitis, the counterparts of gingivitis and periodontitis, respectively. However, many doubts remain about its features. Official diagnostic criteria, globally recognized by the dental community, have not yet been introduced. The latest studies using metagenomic methods are casting doubt on the assumption of microbial equivalence between periodontal and peri-implant crevices. Research on most of the features of peri-implant disease remains at an early stage; moreover, there is not a commonly accepted treatment for it. In any case, although the evidence so far collected is limited, we need to be aware of the current state of the science regarding this topic to better understand and ultimately prevent this disease.

• Implantology
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• v.22 no.4
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• pp.242-254
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• 2018

The aim of the current study was to evaluate the results of horizontal guided bone regeneration (GBR) with xenograf t (deproteinized bovine bone mineral, DBBM), allograf t (irradiated allogenic cancellous bone and marrow), titanium membrane, resorbable collagen membrane, and advanced platelet-rich fibrin (A-PRF) in the anterior maxilla. The titanium membrane was used in this study has a three-dimensional (3D) shape that can cover ridge defects. Case 1. A 32-year-old female patient presented with discomfort due to mobility and pus discharge on tooth #11. Three months after extracting tooth #11, diagnostic software (R2 GATE diagnostic software, Megagen, Daegu, Korea) was used to establish the treatment plan for implant placement. At the first stage of implant surgery, GBR for horizontal augmentation was performed with DBBM ($Bio-Oss^{(R)}$, Geistlich, Wolhusen, Switzerland), irradiated allogenic cancellous bone and marrow (ICB $cancellous^{(R)}$, Rocky Mountain Tissue Bank, Denver, USA), 3D-titanium membrane ($i-Gen^{(R)}$, Megagen, Daegu, Korea), resorbable collagen membrane (Collagen $membrane^{(R)}$, Genoss, Suwon, Korea), and A-PRF because there was approximately 4 mm labial dehiscence after implant placement. Five months after placing the implant, the second stage of implant surgery was performed, and healing abutment was connected after removal of the 3D-titanium membrane. Five months after the second stage of implant surgery was done, the final prosthesis was then delivered. Case 2. A 35-year-old female patient presented with discomfort due to pain and mobility of implant #21. Removal of implant #21 fixture was planned simultaneously with placement of the new implant fixture. At the first stage of implant surgery, GBR for horizontal augmentation was performed with DBBM ($Bio-Oss^{(R)}$), irradiated allogenic cancellous bone and marrow (ICB $cancellous^{(R)}$), 3D-titanium membrane ($i-Gen^{(R)}$), resorbable collagen membrane (Ossix $plus^{(R)}$, Datum, Telrad, Israel), and A-PRF because there was approximately 7 mm labial dehiscence after implant placement. At the second stage of implant surgery six months after implant placement, healing abutment was connected after removing the 3D-titanium membrane. Nine months after the second stage of implant surgery was done, the final prosthesis was then delivered. In these two clinical cases, wound healing of the operation sites was uneventful. All implants were clinically stable without inflammation or additional bone loss, and there was no discomfort to the patient. With the non-resorbable titanium membrane, the ability of bone formation in the space was stably maintained in three dimensions, and A-PRF might influence soft tissue healing. This limited study suggests that aesthetic results can be achieved with GBR using 3D-titanium membrane and A-PRF in the anterior maxilla. However, long-term follow-up evaluation should be performed.

• Restorative Dentistry and Endodontics
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• v.45 no.2
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• pp.17.1-17.10
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• 2020

Objectives: Citation analysis provides a unique insight into how scientific interests and research trends have changed over time. The aim of this study was to report on the 50 top-cited papers in dental stem cell research using the Science Citation Index Expanded provided by the Web of Science database to determine the academic importance of each contribution. Materials and Methods: After the screening, article title and type, total citations and citations per year, publication journal, publication year, first and senior authors, country of origin, institution, and university of reprint author were documented for the 50 top-cited articles in dental stem cell research. Keyword analysis was performed to determine which keywords were most/least popular. Results: Top 50-cited articles were cited between 179 to 2,275 times. The majority of papers were published in 2008 and originated from the United States with the highest contribution from the National Institute of Dental & Craniofacial Research. Journal of Dental Research published the highest number of top-cited articles, followed by Stem Cells and Journal of Endodontics. The greatest number of articles was published by two individual authors, Shi and Gronthos. Among 197 unique keywords, dental pulp stem cells and mesenchymal stem cells were the most frequently used. Thirty-eight of the 50 most cited articles were original articles, and 37 of them were in the field of basic science. Conclusions: Basic science studies in dental stem cell research published in high impact factor journals had the highest citation rates.

• The Journal of the Korean dental association
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• v.49 no.2
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• pp.95-103
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• 2011

Purpose : The purpose of this study was to identify and assess factors that may contribute to pain of patients undergoing implant surgery. Materials and Methods: A total of 24 patients who underwent implant surgery were included in the study. Each patient's anxiety was measured using Corah's dental anxiety score(DAS) and modified Spielberger's state-trait anxiety inventory(STAI) immediately after the operation. Also, level of pain was measured using visual analog scale(VAS) during the operation and 48 hours after the surgery. The effect of various factors, such as demographic variables, previous dental experiences and operation time were also analyzed. Results: Postoperative pain levels were relatively low than expected. However, DAS and STAI were high among patients, and it showed that patients had anxieties about implant surgery according to DAS and STAI values. The previous dental experience did not affect the pain level, but the duration of surgery and the presence of accompanied advanced surgery did. Conclusion: To reduce patient's pain, proper management of anxiety will be required and careful attention is needed when performing local infiltration.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.3
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• pp.355-364
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• 2008

Skeletal anterior open bite is a difficult problem to correct in orthodontic treatment. To treat adult patients who have skeletal anterior open bite, we considered two methods. Combination treatment of orthodontics & surgery and camouflage orthodontic treatment. In adults, treatment of severe skeletal anterior open bite consists mainly of surgically repositioning the maxilla or the mandible. However, camouflage therapy is often the treatment of choice for skeletal open bite patients who have mild to moderate skeletal discrepancies when growth modification is no longer possible. But excellent results generally require careful coordination of the orthodontic and surgical phases of treatment. This is a case report of a skeletal anterior open bite patients who were treated with orthodontic treatment and orthognathic surgery. First case was diagnosed as skeletal class I malocclusion & bimaxillary protrusion with anterior open bite, and finally treatment ended for removal of open bite with orthodontic procedure and bimaxillary anterior segmental osteotomy surgery. Second case was diagnosed as skeletal class II malocclusion with open bite & mandibular retrusion, and was treated with only camouflage orthodontics because she feared to have a surgery. In a regular follow up visit after debonding we proposed to the patient advanced genioplasty, and in her agreement her facial esthetics was improved through the surgery.

• The Journal of Advanced Prosthodontics
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• v.9 no.5
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• pp.381-386
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• 2017

PURPOSE. To integrate extra-oral facial scanning information with CAD/CAM complete dentures to immediately rehabilitate terminal dentition. MATERIALS AND METHODS. Ten patients with terminal dentition scheduled for total extraction and immediate denture placement were recruited for this study. The patients were submitted to a facial scanning procedure using the in-office PritiMirror scanner with bite registration records in-situ. Definitive stone cast models and bite records were subsequently submitted to a lab scanning procedure using the lab scanner (iSeries DWOS; Dental Wings). The scanned models were used to create a virtual teeth setup of a complete denture. Using the intra-oral bite records as a reference, the virtual setup was incorporated in the facial scan thereby facilitating a virtual clinical evaluation (teeth try-in) phase. After applying necessary adjustments, the virtual setup was submitted to a CAM procedure where a 5-axis industrial milling machine (M7 CNC; Darton AG General) was used to fabricate a full-milled PMMA immediate provisional prosthesis. RESULTS. Total extractions were performed, the dentures were immediately inserted, and subjective clinical fit was evaluated. The immediate provisional prostheses were inserted and clinical fit, occlusion/articulation, and esthetics were subjectively assessed; the results were deemed satisfactory. All provisional prostheses remained three months in function with no notable technical complications. CONCLUSION. Ten patients with terminal dentition were treated using a complete digital approach to fabricate complete dentures using CAD/CAM technology. The proposed technique has the potential to accelerate the rehabilitation procedure starting from immediate denture to final implant-supported prosthesis leading to more predictable functional and aesthetics outcomes.

• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.131-136
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• 2004

Osseointegration involves anchoring dental implants to stable bone rather than to soft-tissue. Clinical osseointegration is currently defined as the process whereby alloplastic material is asymptomatically and rigidly fixed and maintained in bone during functional loading. Full osseointegration is necessary for the success of long-term dental implants. Recent developments in computer assisted measurement of bone formation have improved maxillofacial examination and osseointegration. Computer assisted examination has also proved effective in dental implantology. This investigation was aimed to determine osseointegration in immediate and delayed implantation in the dog mandible using dental computed tomography (CT) and bone scintigraphy. Five adult (mean age of 2 years) mongrel dogs with a mean weight of 9.1 kg were used in this investigation. Titanium alloy implant systems with 4 mm in diameter and 10 mm in length were chosen 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, dental CT and scintigraphy were conducted. The CT and scintigraphic images indicate that reconstruction of bone surrounding of the immediate implant can be as successful as reconstruction of bone surrounding of the delayed implant.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.39
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• pp.13.1-13.8
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• 2017

Background: Oronasal/antral communication, loss of teeth and/or tooth-supporting bone, and facial contour deformity may occur as a consequence of maxillectomy for cancer. As a result, speaking, chewing, swallowing, and appearance are variably affected. The restoration is focused on rebuilding the oronasal wall, using either flaps (local or free) for primary closure, either prosthetic obturator. Postoperative radiotherapy surely postpones every dental procedure aimed to set fixed devices, often makes it difficult and risky, even unfeasible. Regular prosthesis, tooth-bearing obturator, and endosseous implants (in native and/or transplanted bone) are used in order to complete dental rehabilitation. Zygomatic implantology (ZI) is a valid, usually delayed, multi-staged procedure, either after having primarily closed the oronasal/antral communication or after left it untreated or amended with obturator. The present paper is an early report of a relatively new, one-stage approach for rehabilitation of patients after tumour resection, with palatal repair with loco-regional flaps and zygomatic implant insertion: supposed advantages are concentration of surgical procedures, reduced time of rehabilitation, and lowered patient discomfort. Cases presentation: We report three patients who underwent alveolo-maxillary resection for cancer and had the resulting oroantral communication directly closed with loco-regional flaps. Simultaneous zygomatic implant insertion was added, in view of granting the optimal dental rehabilitation. Conclusions: All surgical procedures were successful in terms of oroantral separation and implant survival. One patient had the fixed dental restoration just after 3 months, and the others had to receive postoperative radiotherapy; thus, rehabilitation timing was longer, as expected. We think this approach could improve the outcome in selected patients.