The objective of this study was to evaluate the effect of anchor-guiding sleeve length on the accuracy of computer-guided flapless implant surgery in edentulous cases. Twelve identical polyurethane edentulous mandibular models were equally divided into short and long anchor-guiding sleeve groups based on the type of anchor-guiding sleeve. After implant placement and scan body connections, digital impressions were taken using the intraoral scanner.
View Article and Find Full Text PDFThis study aimed to evaluate bone regeneration within infected extraction sockets with bone defects using cone-beam computed tomography (CBCT) at a 1-year follow-up after implant placement in a prosthetically driven implant position. Forty-eight patients requiring premolar or molar tooth extraction due to bone defects caused by periodontal diseases were included. Vertical and horizontal bone volumes were assessed by overlapping the CBCT scan images with the full digital process.
View Article and Find Full Text PDFThe all-on-4 implant concept has been used to overcome anatomic limitations and has been reported to have high success rates. A verification device is commonly used to transfer the position of the angled distal abutment accurately. This article describes a digital workflow for fabricating a verification device to position the angled distal abutment with a hexagon connection during computer-guided flapless surgery.
View Article and Find Full Text PDFThe all-on-4 concept, which is used to rehabilitate edentulous patients, can present with mechanical complications such as screw loosening and fracture. The purpose of this study was to evaluate the stress patterns induced in the prosthetic screws by the different prosthetic screw and abutment designs in the all-on-4 concept using finite element analysis. Von Mises stress values on 6 groups of each screw type, including short and narrow screw, short abutment; short and wide screw, short abutment; long and wide screw, short abutment; short and narrow screw, long abutment; short and wide screw, long abutment; and long and wide screw, long abutment, were compared under a cantilever loading of 200 N that was applied on the farther posterior to the position of the connection between the distal implant and the metal framework.
View Article and Find Full Text PDFImplant-supported overdentures can significantly increase function and satisfaction during the first year and can last for 5 to 10 years. The 2-implant-supported mandibular overdenture is recommended as a standard treatment for edentulous patients. In the recent years, studies have reported the use of digital complete dentures.
View Article and Find Full Text PDFBackground: Immediate loading has shown positive results for total, partial, or single edentulism. The effects of BMP-2 addition to graft materials on bone formation and implant stability in the early stages of healing have rarely been studied, especially in patients with severely atrophic maxillae.
Purpose: To evaluate the effects of simultaneously placed immediate non-functional loaded implants and bone morphogenetic protein-2 (BMP-2)-loaded Bio-Oss collagen, on bone formation and implant stability during the early healing stages of patients with a severely atrophic posterior maxilla using crestal approach.
A double-scan procedure is commonly performed in the process of fabricating an implant surgical template; however, this entails the disadvantage of recording 2 cone beam computed tomography (CBCT) scans requiring additional time, effort, and costs. The purpose of this article is to introduce a digital protocol to acquire adequate preoperative diagnostic information for a fully edentulous patient, using the existing complete denture with a metal framework, an intraoral scanner, and CBCT.
View Article and Find Full Text PDFComput Methods Biomech Biomed Engin
February 2019
The purpose of this study is to measure the failure risk of a crown depending on the cusp angle. Three all-ceramic crown models consisting of C (high incline), C (middle incline), and C (low incline) are designed. Stress is applied to the crown with Loading case-1 (top of cusp tip) and Loading case-2 (middle of cusp ridge) with the use of FEA software.
View Article and Find Full Text PDFThe conversion of a denture into an interim implant-supported, screw-retained restoration has become the standard method for immediate interim restoration in patients with complete edentulism. The most critical steps of the denture conversion process are the creation of appropriate denture access holes to prevent displacement of the denture by the interim cylinders and removal of the denture flanges to facilitate both good esthetics and accessibility for oral hygiene after the denture is connected to the interim cylinders. This article presents a digital technique for designing and fabricating an interim implant-supported, fixed prosthesis for edentulous patients.
View Article and Find Full Text PDFPurpose: In the presence of severe sinus mucosal thickening, the ostium can be blocked when the sinus membrane is lifted, causing drainage disturbances and sinusitis. Here, we present 3 cases in which maxillary sinus floor elevation was performed using a crestal approach in the presence of severe sinus mucosal thickening (>10 mm).
Materials And Methods: The effects of maxillary sinus floor elevation using the crestal approach technique on sinus mucosal thickening and bone formation in the sinus were evaluated using cone beam computed tomography.
An interim restoration is a prototype for the definitive prosthesis and preserves the occlusal information and the original vertical dimension of the occlusion. Several techniques have been developed to transfer the information from implant-supported fixed interim to definitive restoration. However, these conventional techniques have limitations, and they are time-consuming, require making impressions and stone casts, and mounting in an articulator.
View Article and Find Full Text PDFFew studies have reported the application of digital technology for the process of impression and interocclusal recordings in edentulous patients. This article describes a digitizing system for generating digital edentulous models with a jaw relationship by taking direct digital impressions and a virtual bite registration using intraoral digital scanning. A specialized scan retractor was used to make digital impressions of edentulous jaws in patients' mouths using an intraoral scanner.
View Article and Find Full Text PDFPurpose: Antral pseudocysts classically have a well-defined, hyperdense, unilocular, dome-shaped appearance in radiographs. The best therapeutic approach for treating these cysts in the context of sinus floor augmentation remains controversial. This article presents a new technique that allows both sinus membrane elevation and cyst removal through a crestal approach in patients with pseudocysts in the maxillary sinus.
View Article and Find Full Text PDFFabricating an immediate complete denture in the conventional manner may be complicated and difficult. The purpose of this article was to describe a fully digital workflow used to fabricate an immediate complete denture before removing the teeth and without the use of conventional impressions or stone casts. The digital data for the workflow were acquired using an intraoral scanner and were then used to design the denture base and teeth after deleting any remaining tooth images from the virtual 3-dimensional image of the jaw.
View Article and Find Full Text PDFFew studies have evaluated direct digital scans of edentulous jaws using intraoral scanners because it is difficult to scan edentulous sites that are smooth and devoid of features. A scanning technique is introduced for making direct digital scans of edentulous jaws with intraoral scanners in patients with a broad palate.
View Article and Find Full Text PDFJ Oral Maxillofac Surg
December 2017
Purpose: The purpose of this article was to describe a fully digital workflow used to perform computer-guided flapless implant placement in an edentulous patient without the use of conventional impressions, models, or a radiographic guide.
Materials And Methods: Digital data for the workflow were acquired using an intraoral scanner and cone-beam computed tomography (CBCT). The image fusion of the intraoral scan data and CBCT data was performed by matching resin markers placed in the patient's mouth.
J Prosthodont Res
January 2018
Patient: A 60-year-old man presented for refabrication of his maxillary complete denture. In this case, a digital process was chosen to replace the ill-fitted complete maxillary denture. A specialized scan retractor was used to retract the mobile tissues of the lips, cheeks and vestibule while taking a digital impression.
View Article and Find Full Text PDFJ Oral Maxillofac Surg
August 2016
Purpose: Titanium (Ti) alloys have received considerable attention as materials for oral and maxillofacial surgery, which require high mechanical strength, osteosynthesis, and biocompatibility. The objective was to implant miniplates fabricated from commercially pure Ti (CP Ti) and newly developed Ti-silver (Ag) alloy in fractured mandibles of adult dogs after preliminary mechanical and biological characterization.
Materials And Methods: The surface characteristics, biocompatibility, and pre-osteoblast adhesion and proliferation of CP Ti (grade 3) and Ti-Ag (2 at% Ag) alloys were evaluated.
J Korean Assoc Oral Maxillofac Surg
February 2016
Objectives: In this study we evaluated heat generation during the low-speed drilling procedure without irrigation.
Materials And Methods: Ten artificial bone blocks that were similar to human D1 bone were used in this study. The baseline temperature was 37.
Aims: To date, 13 genes causing maturity-onset diabetes of the young (MODY) have been identified. However, there is a big discrepancy in the genetic locus between Asian and Caucasian patients with MODY. Thus, we conducted whole-exome sequencing in Korean MODY families to identify causative gene variants.
View Article and Find Full Text PDFPurpose: Previous studies have shown that the subperiosteal tunneling procedure in vertical ridge augmentation accelerates healing after grafting and prevents graft exposure, with minor postoperative complications. It is conceivable that new bone formation would be greater with the tunneling procedure than with the flap procedure, because the former is minimally invasive. This hypothesis was tested in this study by comparing new bone formation between the flap and tunneling procedures after vertical ridge augmentation using xenogenous bone blocks in a canine mandible model.
View Article and Find Full Text PDFAnn Pediatr Endocrinol Metab
December 2013
Purpose: It has been reported that antithroglobulin (anti-TG) antibody is increased in the sera of both children with transient congenital hypothyroidism and their mothers. And transplacental transport of thyroid autoantibody was proposed as the pathogenesis of transient congenital hypothyroidism. However this is not known in nontransient congenital hypothyroidism.
View Article and Find Full Text PDFAnn Pediatr Endocrinol Metab
September 2013
Purpose: 45,XY,t(13;14)(q10;q10) karyotype can suggest infertility associated with more or less severe oligospermia in male adults. In addition, 45,XX,t(13;14)(q10;q10) karyotype carries reproductive risks such as miscarriage or infertility in female adults. However, reports on the phenotype of this karyotype in children are very rare.
View Article and Find Full Text PDF