• The Journal of Korean Academy of Prosthodontics
• /
• v.53 no.2
• /
• pp.111-119
• /
• 2015

Purpose: The objective of this study was to evaluate the accuracy of a stereolithographic surgical guide that was made with information from intraoral digital impressions and cone beam CT (CBCT). Materials and methods: Six sets of resin maxilla and mandible models with missing teeth were used in this study. Intraoral digital impressions were made. The virtual models provided by these intraoral digital impressions and by the CBCT scan images of the resin models were used to create a surgical guide. Implant surgery was performed on the resin models using the surgical guide. After implant placement, the models were subjected to another CBCT scan to compare the planned and actual implant positions. Deviations in position, depth and axis between the planned and actual positions were measured for each implant. Results: The mean deviation of the insertion point and angulation were 0.28 mm and $0.26^{\circ}$, apex point were 0.11 mm and 0.14 mm respectively. The implants were situated at a mean of 0.44 mm coronal to the planned vertical position. Conclusion: This study demonstrates that stereolithographic surgical guides created without the use of impressions and stone models show promising accuracy in implant placement.

• The Journal of Korean Academy of Prosthodontics
• /
• v.50 no.3
• /
• pp.191-197
• /
• 2012

Esthetics is important in restoring maxillary anterior area. Alveolar bone resorption and loss of interdental papilla may be minimized by immediate implantation. Previous studies showed successful results with the immediate implantation in healthy extraction socket, while many of these studies objected the immediate implantation into extraction sites with periapical lesions. Recent studies, however, reported successful results of the immediate implantation into extraction sites with periapical lesions with careful debridement of extraction sockets and general medication of antibiotics prior to implantation. A 73-year-old female visited the department of Prosthodontics in ${\bigcirc}{\bigcirc}$ University Dental Hospital with the chief complaint of fallen post-core and crown on left maxillary incisor. Although the incisor was with vertical root fracture and periapical lesion, the immediate implantation following the extraction of tooth was planned. Thorough socket debridement, irrigation with chlorhexidine, and tetracycline soaking were followed by immediate implantation. The general medication of antibiotics (Moxicle Tab.$^{(R)}$, 375 mg) was prescribed before and after the surgery. Immediate provisional restoration was delivered two days after the surgery, and the definitive metal-ceramic restoration was placed about six months later after reproducing the emergence profile from the provisional restoration. This case presents satisfying result esthetically and functionally upto two years after the placement of prosthesis with the harmonious gingival line and no loss of marginal bone.

• The Journal of the Korean dental association
• /
• v.56 no.11
• /
• pp.616-621
• /
• 2018

This clinical case highlights the failure of long length implants, and the prosthodontic procedures necessary to rehabilitate the maxillary dentition of a patient with microstomia. The integrated digital technology of intra-oral scanning, computer-aided design, and three-dimensional printing can provide an alternative method to make conventional impressions for patients with microstomia who cannot insert the appropriate tray in their mouths.

• The Journal of Korean Academy of Prosthodontics
• /
• v.48 no.4
• /
• pp.280-286
• /
• 2010

Purpose: This study evaluated the detorque values of screws in a multiple implant-supported superstructure using stone casts made with 2 different impression techniques. Material and methods: A fully edentulous mandibular master model and a metal framework directly connected to four implants (Br${\aa}$nemark $System^{(R)}$; Nobel Biocare AB) with a passive fit to each other were fabricated. Six experimental stone casts (Group 1) were made with 6 non-splinted impressions on a master cast and another 6 experimental casts (Group 2) were made with 6 acrylic resin splinted impressions. The detorque values of screws ($TorqTite^{(R)}$ GoldAdapt Abutment Screw; Nobel Biocare AB) were measured twice after the metal framework was fastened onto each experimental stone cast with 20 Ncm torque. Detorque values were analyzed using the mixed model with the fixed effect of screw and reading and the random effect of model for the repeated measured data at a .05 level of ignificance. Results: The mean detorque values were 7.9 Ncm (Group 1) and 8.1 Ncm (Group 2), and the mean of minimum detorque values were 6.1 Ncm (Group 1) and 6.5 Ncm (Group 2). No statistically significant differences between 2 groups were found and no statistically significant differences among 4 screws were found for detorque values. No statistically significant differences between 2 groups were also found for minimum detorque values. Conclusion: In a multiple external hexagon implant-supported prosthesis, no significant differences between 2 groups were found for detorque values and for minimum detorque values. There seems to be no significant differences in screw joint stability between 2 stone cast groups made with 2 different impression techniques.

• The Journal of Korean Academy of Prosthodontics
• /
• v.56 no.1
• /
• pp.88-94
• /
• 2018

Recently, digital implant systems are expanding its influence in dental area. Due to technical improvement, they jumped over their limits nowadays. We can use these newest systems to treat edentulous patient, from implant surgery to fabrication of prosthesis. In this case, The patient was a fifty years old female. She had a full edentulous ridge on mandible and wanted to reconstruct occlusion with using implants. We planned to use digital implant system with "all-on-4" concept on mandible and produced surgical guide for flapless implant surgery. After the surgery, we tried to fabricate full arch prosthesis just using a digital devices and confirmed satisfying result.

• The Journal of Korean Academy of Prosthodontics
• /
• v.62 no.1
• /
• pp.82-94
• /
• 2024

This is a case report of complete mouth rehabilitation in a patient with generalized attrition and loss of posterior support. After analyzing the condition of the temporomandibular joint, multiple implants were placed to restore collapsed occlusion. Fixture/abutment level intraoral scanning was done instead of using conventional impression materials which entail multiple bite registration for cross-mounting. A 'jaw motion tracking'device, 'digital face-bow transfer', and 'double scan technique' which enables duplicating temporary restoration to definitive restoration were used to fabricate definitive prostheses. By using various digital techniques, complete mouth rehabilitation was done with minimal chair time in a patient with unstable occlusion.

• The Journal of Korean Academy of Prosthodontics
• /
• v.59 no.1
• /
• pp.79-87
• /
• 2021

The digital workflow of optical impressions by the intraoral scanner and CADCAM manufacture of dental prostheses is actively developing. The complex process of traditional impression taking, definite cast fabrication, wax pattern making, and casting has been shortened, and the number of patient's visits can also be reduced. Advances in intraoral scanner technology have increased the precision and accuracy of optical impression, and its indication is progressively widened toward the long span fixed dental prosthesis. This case report describes the long span implant case, and the operator fully utilized digital workflow such as computer-guided implant surgical template and CAD-CAM produced restoration after the digital impression. The provisional restoration and customized abutments were prepared with the optical impression taken on the same day of implant surgery. Moreover, the final prosthesis was fabricated with the digital scan while utilizing the same customized abutment from the provisional restoration. During the data acquisition step, stl data of customized abutments, previously scanned at the time of provisional restoration delivery, were imported and automatically aligned with digital impression data using an 'A.I. abutment matching algorithm' the intraoral scanner software. By using this algorithm, it was possible to obtain the subgingival margin without the gingival retraction or abutment removal. Using the digital intraoral scanner's advanced functions, the operator could shorten the total treatment time. So that both the patient and the clinician could experience convenient and effective treatment, and it was possible to manufacture a prosthesis with predictability.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.39 no.4
• /
• pp.267-275
• /
• 2023

To obtain better esthetic results when immediately placing a dental implant, the soft tissue surrounding the implant must be conditioned during healing of the extraction socket. To this end, the emergence profile can be customized through immediate restoration of the provisional prosthesis, and good clinical results can be obtained at the time of definitive restoration in the future, resulting in high patient satisfaction. In this case, horizontal root fracture occurred after trauma to both maxillary central incisors. Immediate implant placement and loading was planned considering aesthetics and alveolar bone condition. By taking an impression using a digital intraoral scanner, a digital diagnostic wax-up was performed to make a more aesthetic prosthesis without applying external force to the traumatized teeth. Based on this, the ideal placement location was determined and immediate implant placement was performed using a 3D printed surgical guide. The provisional prosthesis was restored 5 days after placement, and the definitive zirconia crown was restored through soft tissue conditioning and customization using the shape of the provisional prosthesis for 3 months.

• The Journal of Korean Academy of Prosthodontics
• /
• v.60 no.4
• /
• pp.374-381
• /
• 2022

This case report introduces a 74-year-old male patient who visited retention deficiency of the mandibular implant overdenture, which was fabricated 20 years ago. When the existing dentures were used, the vertical dimension was reduced, the maxillary complete denture lacked lip support and retention, and the mandibular overdenture lacked clip retention due to damage to the bar attachment. After removing the damaged bar attachment, it was replaced with a ball attachment, and impressions were taken using the DENTCA^TM Tray and then the vertical dimension was measured. The gothic arch tracing was performed to record the centric relation. Obtained impressions were scanned and the shape of final dentures was designed using software and try-in dentures were fabricated using 3D printer. After evaluating the occlusal plane, occlusal relationship, facial shape, and pronunciation using the try-in dentures, the bite registration was recorded, and the final denture was manufactured based on this. The inner surface of the denture was adjusted and bilateral balanced occlusion was formed, and the housing was connected to the mandibular denture by a direct method. This case reports have shown satisfactory resultin recovering improved retention and esthetic outcome by increasing the vertical dimension and the lip support using CAD-CAM technique and the ball attachment.

• Journal of the Korean Academy of Esthetic Dentistry
• /
• v.25 no.1
• /
• pp.35-49
• /
• 2016

With the increasing demand for aesthetic implant dentistry, the importance of implant restoration is emphasized not only in the functional aspect but also in the aesthetic aspect. The aesthetic restoration of dental implants in the anterior maxilla is a challenge for clinicians because it requires proper harmony in three following conditions; reconstruction of hard tissue, soft tissue, and aesthetic prosthesis. The soft tissue aesthetics are dependent upon the condition of the supporting hard tissue because the osseous structure provides a framework for the development of a healthy and aesthetic soft tissue interface. Therefore, the augmentation of hard tissue is a first step and especially, optimal 3-dimensional position of implant is the most important factor in aesthetic implant restoration. The management of soft tissue is a second step, and the final step is a restoration of harmonic prosthesis using provisional restoration with proper emergence profile. This clinical report describes the procedure of bone augmentation in labial dehiscence defect, Vascularized Interpositional Periosteal-Connective Tissue (VIP-CT) flap for aesthetic anterior soft tissue, and the importance of provisional restoration and impression taking stage with customized impression coping.