• The Journal of Advanced Prosthodontics
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• v.11 no.2
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• pp.88-94
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• 2019

PURPOSE. This study was conducted to investigate patterns of adjacent tooth displacement in the posterior implant with interproximal contact loss (ICL) by 3-D digital superimposition method. MATERIALS AND METHODS. Posterior partially edentulous patients, restored with implant fixed partial prostheses before 2011 and suffered from food impaction of ICL between 2009 and 2011, were included. Two dental casts, at the time of delivery and at the time of food impaction in a same patient, was converted into 3-D digital models through scanning and superimposition was performed to assess chronologic changes of the dentition. Directions of tooth displacement were evaluated and the amount of ICL was calculated. Correlations between the amount of ICL and elapsed time, or between the amount of ICL and age after function, were assessed at a significance level of P<.05. RESULTS. A total number of 13 patients (8 males, 5 females) with a mean age of $65.76{\pm}9.94years$ and 17 areas (4 maxillae, 13 mandibles) were included in this retrospective study. Teeth adjacent to the implant restoration showed complex displacements but characteristic tendency according to the location of the arch. The mean amount of ICL was $0.33{\pm}0.14mm$. Elapsed time from function to ICL was $61.47{\pm}31.27months$. There were no significant differences between the amount of ICL and elapsed time, or age (P>.05). CONCLUSION. Natural teeth showed various directional movements to result in occlusal change in the arch. The 3-D superimposition of chronologic digital models was a helpful method to analyze the changes of dentition and individual tooth displacement adjacent to implant restoration.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.2
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• pp.168-174
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• 2022

In case of gingival recession or bone defect in maxillary anterior implant treatment, it is not easy to obtain satisfactory clinical results. In this case, loss of the labial alveolar plate was diagnosed in the maxillary right central incisor, so after tooth extraction, soft tissue was secured and implant placement with bone graft was planned. In addition, digital guide surgery was performed for the ideal implant position, and GBR (Guided Bone Regeneration) was accompanied with the xenogeneic bone and the autologous bone collected from the mandibular ramus since alveolar bone defects were extensive. After a sufficient period of osseointegration of the implant, a temporary prosthesis was fabricated through secondary stage surgery and impression taking, and through periodic external adjustment, the shape of soft tissue was improved. In the final prosthesis fabrication, a color tone of natural teeth was induced by an gold anodized customized abutment, and an aesthetic and functional zirconia prosthesis with reproducing the shape of the temporary prosthesis through intraoral scan was delivered.

• The Journal of Advanced Prosthodontics
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• v.12 no.1
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• pp.15-21
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• 2020

PURPOSE. The aim of the current study was to analyze treatment concepts of a cohort of German dentists for planning, fabrication, and maintenance of implant-supported fixed and removable restorations. MATERIALS AND METHODS. A questionnaire including queries about experiences with implant-supported restorations as well as prosthetic and maintenance treatment concepts for supplying patients with fixed and removable implant-supported prosthetic restorations was developed and sent to 350 dental offices registered in the municipal area of Leipzig, Germany. RESULTS. An overall total of 62 returned questionnaires were included in the analyses, which relates to a response rate of 17.7%. Participating dentists were more involved in the prosthetic aspects of implant dentistry rather than surgery, while prosthetic concepts such as backward planning, digital processing, and application of all-ceramic materials were not commonly performed. Simple attachments were preferred over complex retention systems in removable implant-supported restorations. Tooth/implant-supported fixed denture prostheses as well as removable denture prostheses with supporting posterior implants were not regarded as a favorable treatment option. CONCLUSION. Within the limitations of the study, the data indicate that dentists favor simple and conventional treatment approaches in implant prosthetics. Prosthetic aspects in the planning of implant-supported restorations are often neglected. Prosthetic treatment guidelines and aspects should commonly be considered in the planning phase of implant-supported prosthetic restorations, and awareness should be increased in postgraduate education.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.2
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• pp.157-166
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• 2015

This article describes how to use CBCT and an intraoral scanner in a fully edentulous case that enables the clinician to place implants with flapless guided surgery and to engage prefabricated, customized implant abutments at the time of implant surgery, with only 1 clinical consultation before implant surgery. The patient's existing denture is used to simulate the teeth, the soft tissue and the vertical dimension of occlusion, and jaw relationship in the fully edentulous jaw. It provides clinicians with a fast workflow and improves clinical efficiency.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.31 no.2
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• pp.64-74
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• 2022

Digital dentistry is becoming a mainstream of dental practice. We are already used to intraoral scan, guided implant surgery, manufacture of prosthesis (CAD-CAM) in our daily practice; those are not sensational anymore. However, treatment planning with digital simulations is not spotlighted enough. In this report, a digital mockup was utilized to visualize the final goal of maxillary rehabilitation including all anterior and posterior teeth, and persuade a patient who wanted restoration of only anterior teeth. We will also discuss the use of digital mockup and its actual copy as the guide of altered vertical dimension through the clinical process.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.4
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• pp.362-373
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• 2022

For a full-mouth fixed prosthetic treatment of the edentulous patient, it is essential to confirm the proper tooth position and thorough evaluation of the remaining alveolar bone and soft tissue before surgery. CAD-CAM dentistry and guided implant surgery have such advantages of providing simultaneous planning of surgery and prosthetic treatment to ensure pre-knowledge of the treatment. In this clinical case, using the digital technology, digital temporary denture fabrication, esthetic evaluation before fixed prostheses treatment, and guided surgery planning was possible. After the surgery, previously obtained data was used for fabricating fixed temporary prostheses. Definitive zirconia prostheses transferred from the provisional prostheses were fabricated and functionally and esthetically satisfying results were obtained.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.1
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• pp.26-32
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• 2023

Dental trauma is common in active children and adolescents. Among them, in the case of ankylosis due to avulsion, diagnosis through clinical examination is important, and the treatment is important for esthetic prosthetic restoration after adulthood. This case is a case of esthetic prosthetic restoration of maxillary anterior teeth through decoronation and implant. After that, space was maintained for prosthetic restoration using a decoronated crown. After becoming an adult, precise implant placement and esthetic prosthetic restoration were possible using guide surgery. For soft tissue support, the temporary crown were replaced by changing the contours of the temporary crown, and the final esthetic prosthesis was fabricated by digital wax-up.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.3
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• pp.234-242
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• 2024

Immediate implant placement and restoration have the advantage of shortening the treatment period and maintaining aesthetics until final restoration. However, single implant restoration in the maxillary anterior region may be aesthetically difficult, and surgical trauma delivered to soft and hard tissues during implant placement may affect future aesthetic results. In order to obtain predictable results during anterior implant placement and restoration, surgery and restoration plans must consider the height of the interdental bone, characteristics of the gingiva, and morphological characteristics of the patient's teeth. In this case, we attempted to reproduce the emergence profile and stabilized soft tissue through gingiva modification and digital impression of a labially placed maxillary anterior implant in a patient who desired porcelain fused-metal (PFM) restoration due to economic issues.

• Journal of Periodontal and Implant Science
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• v.42 no.2
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• pp.39-44
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• 2012

Purpose: Special care is necessary to avoid invading important anatomic structures during surgery when presurgical planning is made based on radiographs. However, none of these types of radiography represents a perfect modality. The purpose of this study was to determine the reliability of presurgical planning based on the use of two types of radiographic image (digital panoramic radiography [DPR] and cone-beam computed tomography [CBCT]) by beginner dentists to place implants, and to quantify differences in measurements between radiographic images and real specimens. Methods: Ten fresh cadavers without posterior teeth were used, and twelve practitioners who had no experience of implant surgery performed implant surgery after 10 hours of basic instruction using conventional surgical guide based on CBCT or DPR. Two types of measurement error were evaluated: 1) the presurgical measurement error, defined as that between the presurgical and postsurgical measurements in each modality of radiographic analysis, and 2) the measurement error between postsurgical radiography and the real specimen. Results: The mean presurgical measurement error was significantly smaller for CBCT than for DPR in the maxillary region, whereas it did not differ significantly between the two imaging modalities in the mandibular region. The mean measurement error between radiography and real specimens was significantly smaller for CBCT than for DPR in the maxillary region, but did not differ significantly in the mandibular region. Conclusions: Presurgical planning can be performed safely using DPR in the mandible; however, presurgical planning using CBCT is recommended in the maxilla when a structure in a buccolingual location needs to be evaluated because this imaging modality supplies buccolingual information that cannot be obtained from DPR.

• Journal of Periodontal and Implant Science
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• v.53 no.1
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• pp.85-95
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• 2023

Purpose: In recent years, guided implant surgery has been widely used for the convenience of patients and surgeons. Further streamlining the surgical procedure would make implant surgery more convenient. Low-speed water-free conditions are often used in guided implant surgery. Therefore, in this study, we attempted to confirm once again whether drilling was safe at a low speed without water. The main purpose of this study was to evaluate whether a simplified drilling protocol that omits some intermediate steps in the drilling process was safe from the viewpoint of heat generation. Methods: D1 density artificial bone blocks were drilled under 50 rpm, 10 N·cm water-free conditions, and the surface temperature was measured using a digital infrared camera. First, drilling was performed with the sequential drilling method, which is the most widely used technique. Second, for each drill diameter, the temperature change was measured while performing simplified drilling with omission of the previous 1, 2, or 3 steps. Results: In sequential drilling, the heat generated during drilling at all diameters was less than the critical temperature of osteonecrosis (47℃) except for the ⌀2 drill. Statistical significance was observed in all groups when comparing sequential and simplified drilling in the ⌀3.2, ⌀3.8, and ⌀4.3 drills (P<0.001). However, in the simplified drilling procedures, the temperature was below the osteonecrosis threshold temperature (47℃) except for the ⌀4.3 drill with the omission of the previous 3 steps (⌀3.0, ⌀3.2, and ⌀3.8). Conclusions: In general, drilling under low-speed, water-free conditions has shown stable results in terms of heat generation. Simplified drilling showed statistically significantly greater heat generation than sequential drilling. However, most of the diameters and omitted steps seem to be clinically acceptable, so it will be useful if an appropriate selection is made according to the patient's clinical condition.