Implant-supported milled bar overdenture with two implant surgical guides / 대한치과보철학회지

For fully edentulous patients, implant-supported overdenture can be considered to enhance chewing efficiency and denture stability. Implant planning software can be used to fabricate a surgical guide for a more precise consideration of anatomic factors and prediction of the shape of definitive prosthesis. Though there are many possible attachments for implant overdenture, milled bar can be useful due to its splinting effect of implants and rigid support of overdenture. This report presents a case of implant-supported milled bar overdenture after guided implant surgery performed with two surgical guide that was fabricated before and after bone reduction.

Comparison of treatments for maxillary full denture and mandibular implant-supported fixed prosthesis in completely edentulous patients: A case report / 대한치과보철학회지

There are various approaches to treatment for patients with fully edentulous jaw. In maxilla, it is easy to obtain sufficient stability, support, and retention with the traditional full denture method. In mandible, however, there are difficulties caused by anatomical limitations. In this case, treatment with implants can be considered. If it is difficult to place implants in posterior area, a fixed complete denture can be considered, using 4 - 5 implants anterior to mental foramen. This approach has changed in many ways, such as surgical methods and materials used, over the years. This case report compares two approaches and their changes over time, especially in the cases of mandibular fixed prostheses using implants, paired with maxillary complete denture.

Aesthetic implant restoration with alveolar bone graft and digital method on maxillary central incisor: a case report / 대한치과보철학회지

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.

Rehabilitation of posterior support and vertical dimension in a class 3 malocclusion patient: A case report / 대한치과보철학회지

A crossed occlusion resulting from the presence of posterior teeth in one arch but no opposing teeth in the opposite arch results in collapse of the vertical dimension. In this case, the patient has a class III malocclusion with crossed occlusion and anterior crossbite. In order to evaluate the proper vertical dimension, provisional denture was used to stabilize the vertical occlusal dimension for 3 months. After, provisional fixed restoration was used for the stabilizing occlusal relationship and aesthetic improvement for lip support. Definitive prosthesis in implants in the mandible and abutments in the maxillary were using Porcelain-fused-to-metal crown (PFM) crown and the maxillary unilateral edentulous area was treated with removable partial dentures. Through this, proper support of the posterior region and normal anterior occlusal relationship were formed, and the patient was able to obtain aesthetically and functionally satisfactory treatment results.

Analysis of relationship between cracked tooth syndrome and occlusion using Q-ray and T-scan / 대한치과보철학회지

Purpose@#The aim of this study was to evaluate the relationship between the patient's occlusion and a cracked tooth by using T-scan occlusal analysis and a quantitative light-induced fluorescence (QLF) technology. @*Materials and Methods@#This study was carried out on 51 patients having cracked teeth between January, 2019 and December, 2020. The tooth crack was determined with a Q-ray pen and QLF parameters (ΔFmax and ΔRmax) were obtained by a Q-ray software. T-scan tests were conducted to all subjects and then, the occlusal force and disclosing time were analyzed. Mann-Whitney U test was performed to compare the occlusal force and disclosing time between cracked teeth groups and contra-lateral normal teeth groups (α = .05). Mann-Whitney U test was performed to compare ΔFmax and ΔRmax according to the results of cold/bite tests (α = .05). A Spearman correlation analysis was run to determine the relationship between ΔFmax or ΔRmax and occlusal force or disclosing time (α=.05). @*Results@#The mean occlusal force and disclosing time were significantly higher on cracked teeth than on normal teeth (P .05). There was no correlation between ΔFmax or ΔRmax and occlusal force or disclosing time (P > .05). @*Conclusion@#There was a significant relationship between occlusion and cracked tooth syndrome. QLF has the potential to be a valuable tool for the diagnosis of tooth crack in clinical practice.

Analysis of relationship between cracked tooth syndrome and occlusion using Q-ray and T-scan / 대한치과보철학회지

Purpose@#The aim of this study was to evaluate the relationship between the patient's occlusion and a cracked tooth by using T-scan occlusal analysis and a quantitative light-induced fluorescence (QLF) technology. @*Materials and Methods@#This study was carried out on 51 patients having cracked teeth between January, 2019 and December, 2020. The tooth crack was determined with a Q-ray pen and QLF parameters (ΔFmax and ΔRmax) were obtained by a Q-ray software. T-scan tests were conducted to all subjects and then, the occlusal force and disclosing time were analyzed. Mann-Whitney U test was performed to compare the occlusal force and disclosing time between cracked teeth groups and contra-lateral normal teeth groups (α = .05). Mann-Whitney U test was performed to compare ΔFmax and ΔRmax according to the results of cold/bite tests (α = .05). A Spearman correlation analysis was run to determine the relationship between ΔFmax or ΔRmax and occlusal force or disclosing time (α=.05). @*Results@#The mean occlusal force and disclosing time were significantly higher on cracked teeth than on normal teeth (P .05). There was no correlation between ΔFmax or ΔRmax and occlusal force or disclosing time (P > .05). @*Conclusion@#There was a significant relationship between occlusion and cracked tooth syndrome. QLF has the potential to be a valuable tool for the diagnosis of tooth crack in clinical practice.

Comparison of implant stability measurements between a resonance frequency analysis device and a modified damping capacity analysis device: an in vitro study

PURPOSE: A stability-measuring device that utilizes damping capacity analysis (DCA) has recently been introduced in the field of dental implantology. This study aimed to evaluate the sensitivity and reliability of this device by measuring the implant stability of ex vivo samples in comparison with a resonance frequency analysis (RFA) device.METHODS: Six implant beds were prepared in porcine ribs using 3 different drilling protocols to simulate various implant stability conditions. Thirty-six pork ribs and 216 bone-level implants measuring 10 mm in height were used. The implant beds were prepared using 1 of the following 3 drilling protocols: 10-mm drilling depth with a 3.5-mm-diameter twist drill, 5-mm drilling depth with a 4.0-mm-diameter twist drill, and 10-mm drilling depth with a 4.0-mm-diameter twist drill. The first 108 implants were external-connection implants 4.0 mm in diameter, while the other 108 implants were internal-connection implants 4.3 mm in diameter. The peak insertion torque (PIT) during implant placement, the stability values obtained with DCA and RFA devices after implant placement, and the peak removal torque (PRT) during implant removal were measured.RESULTS: The intraclass correlation coefficients (ICCs) of the implant stability quotient (ISQ) results obtained using the RFA device at the medial, distal, ventral, and dorsal points were 0.997, 0.994, 0.994, and 0.998, respectively. The ICCs of the implant stability test (IST) results obtained using the DCA device at the corresponding locations were 0.972, 0.975, 0.974, and 0.976, respectively. Logarithmic relationships between PIT and IST, PIT and ISQ, PRT and IST, and PRT and ISQ were observed. The mean absolute difference between the ISQ and IST values on a Bland-Altman plot was −6.76 (−25.05 to 11.53, P<0.05).CONCLUSIONS: Within the limits of ex vivo studies, measurements made using the RFA and DCA devices were found to be correlated under a variety of stability conditions.

A noninvasive esthetic treatment of isolated microdontia using new high-translucent cubic-phase zirconia (5Y-PSZ) laminate veneers: A case report / 대한치과보철학회지

Current trends in restorative dentistry focus on improving the esthetics and keeping the sound dental tissues as long as possible. The aims of this case report were to describe the successful outcome of cubic-phase zirconia laminate veneers for a patient with isolated microdontia by using a digital workflow, and to describe their clinical implications. A 15-year-old female who had isolated microdontia in combination with spacing visited Ajou University Dental Hospital for esthetic treatment. In this case, 6 maxillary anterior teeth were restored with cubic-phase zirconia laminate veneers without tooth structure removal by using a digital impression, computer-aided design (CAD) software, and computer-aided manufacturing (CAM) procedures. At 6-month follow-up, no distinct mechanical and biological complications were detected and the prostheses exhibited satisfactory esthetics and functions. Due to its favorable tissue responses and enhanced translucency, cubic-phase zirconia can be a suitable strategy for a noninvasive esthetic approach.

Study on application to the field of dentistry using optical coherence tomography (OCT) / 대한치과보철학회지

PURPOSE: This paper describes the basic principles and the feasibility of the field of dental diagnosis of optical coherence tomography (OCT) used in diverse field of medical diagnosis. MATERIALS AND METHODS: In this review, the research data of OCT were searched from PubMed, medical journal and related papers. RESULTS: Generally, OCT is non-invasive and is possible to secure an excellent spatial resolution and real-time images of biological microstructure. CONCLUSION: This review discusses not only the basic principles of operation, types, advantages, disadvantages of OCT but also the future applications of OCT technology and their potential in the field of dental diagnosis.

Study on methodology for the assessment of internal and marginal adaptation on fixed dental prosthesis

This article is to review various methods used to investigate internal and marginal adaptation of fixed dental prostheses, and to summarize a merit, worth, and limitation of each method, using some results of previous studies. The methods of measuring internal and marginal gap are divided into two categories in this study; in vivo and in vitro. In vivo methods are clinical evaluations, including exploration, radiography, and impression technique. In vitro methods are laboratory evaluations such as direct view, cross-sectioning, and silicone replica technique using microscope. Measuring by micro computed tomography (CT) or profilometer is also in vitro methods. In recent years, the development of scanning systems is able to analyze 3-dimensional internal and marginal space in detail. As measuring and analyzing technology become more advanced, the ability to thoroughly examine crown adaptation is becoming both simpler and more efficient.

Maxillary anterior all ceramic restoration using digital impression and CAD/CAM / 대한치과보철학회지

The digital impression technique has been developed for more precise restorations and convenient procedures in prosthodontic treatment compared to the conventional impression technique. Along with the utilization of CAD/CAM, the introduction of digital impression technique actualizes the digitalization of dental treatments. This case is to compare two different prostheses introducing each procedure in detail; one from CAD/CAM after taking digital impression and the other from the conventional technique. A 22-year-old female visited the clinic with the chief complaint of correction of discoloration and shape on maxillary right central incisor. Due to the trauma 8 years ago, the tooth was endodontically treated with post and resin core. The treatment was planned and the procedures were conducted under the patient's consent to treat the tooth with all ceramic crowns in two different ways for comparison. In conclusion, both prostheses presented clinically acceptable results with comparing the internal fitness of two all ceramic crowns. The prosthesis from digital impression, however, showed more errors in respect of internal fitness.