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Introduction. The purpose of this study was to investigate effects of surface treatment of mini-implants in diabetes-induced rabbits by comparing osseointegration around mini-implants. Methods. Twelve New Zealand white rabbits were divided into two groups (alloxan-induced diabetic group and control group). A total of 48 mini-implants were placed after four weeks of diabetic induction. 24 mini-implants were surface-treated with SLA (sandblasted with large grit, and acid etched) and the remaining 24 mini-implants had smooth surfaces. Four weeks after placement, 32 mini-implants were removed from 4 control and 4 diabetic rabbits. Insertion and removal torques were measured. The remaining 16 mini-implants from the two groups were histomorphometrically analyzed. Results. Maximum insertion torque showed no difference between diabetic and control groups, but total insertion energy was higher in control group. In surface-treated mini-implants, maximum removal torque was higher in both diabetic and control groups. Bone-implant contact (BIC) was increased in the control group when compared to the diabetic group. Surface-treated group had higher BIC than smooth surface group in both control and diabetic groups. However, there was no significantly statistical difference. Conclusions. Type 1 diabetes mellitus and surface treatment method of mini-implant affected primary stability of mini-implants. In addition, the use of orthodontic mini-implants in a diabetic patient is likely to show results similar to the healthy patient.

Objective. This study aimed to evaluate effects of type 1 diabetes mellitus and mini-implant placement method on the primary stability of mini-implants by comparing mechanical stability and microstructural/histological differences. Methods. After 4 weeks of diabetic induction, 48 mini-implants (24 self-tapping and 24 self-drilling implants) were placed on the tibia of 6 diabetic and 6 normal rabbits. After 4 weeks, the rabbits were sacrificed. Insertion torque, removal torque, insertion energy, and removal energy were measured with a surgical engine on 8 rabbits. Remaining 4 rabbits were analyzed by microcomputed tomography (micro-CT) and bone histomorphometry. Results. Total insertion energy was higher in self-drilling groups than self-tapping groups in both control and diabetic groups. Diabetic groups had more trabecular separation in bone marrow than the control groups in both SD and ST groups. Micro-CT analysis showed deterioration of bone quality in tibia especially in bone marrow of diabetic rabbits. However, there was no statistically significant correlation between self-drilling and self-tapping group for the remaining measurements in both control and diabetic groups. Conclusions. Type 1 diabetes mellitus and placement method of mini-implant did not affect primary stability of mini-implants.

BackgroundA previous study on the genetic association between single nucleotide polymorphisms in FGFR1OP2/wit3.0 and the long term atrophy of edentulous mandible hypothesized that the excessive jawbone atrophy after dental extraction may be associated with abnormal oral mucosa contraction induced by the FGFR1OP2/wit 3.0 gene. It was reported that the minor allele of rs840869 or rs859024 in FGFR1OP2/wit3.0 was associated with the excessive atrophy of edentulous mandible. The present study represents an attempt to replicate the results of this previous study and to examine the genetic association between polymorphisms in FGFR1OP2 and residual ridge resorption of mandible in a Korean population.Methodology/principal findings134 subjects (70.46 ± 9.02 years) with partially or completely edentulous mandible were recruited. The mandibular bone height was measured following the protocol of the American College of Prosthodontists (ACP). From 24 subjects, seven variants in FGFR1OP2 were discovered and four of them were novel. Selected SNPs that are not in high LD at r2 threshold of 0.8 were genotyped for the remaining population. There was no frequency of the minor allele of SNP rs859024 in Korean population. SNP rs840869 was not associated with residual ridge resorption (p = 0.479). The bone height of the subject with the ss518063493 minor allele (8.52 mm) was shorter than that of those subjects with major alleles (18.96 ± 5.33 mm, p = 0.053).Conclusions/significanceThe patient with minor allele of ss518063493 may be associated with excessive atrophy of edentulous mandible whereas the patients with that of rs840869 are not associated in Korean population. The result from this study may assist in developing a novel genetic diagnostic test and be useful in identifying Koreans susceptible to developing excessive jawbone atrophy after dental extraction.

Purpose: Rotational errors of implants can occur during two stages: when connecting impression copings with implants, and when connecting impression copings with analogs. The aim of this study was to determine ways to minimize these rotational errors. Materials and Methods: Three types of implants were prepared: a tissue-level implant with an internal octagon 8-degree Morse taper connection, a bone-level implant with an internal hex 11-degree Morse taper connection, and a bone-level implant with an external hex connection. Each complex (n = 10 per group) was composed of an implant, an impression coping, and an analog. Implants were embedded in resin blocks and connected with corresponding impression copings. Analogs that reproduced the position of the implants were created by means of a custom-made transfer jig, and rotational errors were measured between implants and analogs. Impression copings and analogs were connected by means of four methods: The impression coping was connected to the implant in a clockwise (CW) or a counterclockwise (CCW) direction before tightening, and the analogs were then connected with impression copings and tightened using a hemostat (Hs) or by hand (Hd). Results: The CW-Hs and CCW-Hd groups exhibited low rotational error (mean ± standard deviation 0.11 ± 0.21 and 0.19 ± 0.34 degrees, respectively), whereas the CW-Hd and CCW-Hs groups exhibited high rotational error (-1.80 ± 0.67 and 2.07 ± 0.75, respectively) in different directions. A strong association was observed between the tightening method and rotational error, and a weak association was observed between the connection type and rotational error. Conclusion: The CW-Hs method was found to be the most suitable for minimizing rotational error between implants and analogs. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to analyze and compare the level and distribution of peri-implant bone stresses associated with mandibular two-implant overdentures with different implant positions. Materials and Methods: Mathematical models of mandibles and overdentures were designed using finite element analysis software. Two intraosseous implants and ball attachment systems were placed in the interforaminal region. The overdenture, which was supported by the two implants, was designed to withstand bilateral and unilateral vertical masticatory loads (total 100 N). In all, eight types of models, which differed according to assigned implant positions, height of attachments, and angulation, were tested: MI (model with implants positioned in the lateral incisor sites), MC (implants in canine sites), MP (implants in premolar sites), MI-Hi (greater height of attachments), MC-M (canine implants placed with mesial inclination), MC-D (canine implants placed with distal inclination), MC-B (canine implants placed with buccal inclination), and MC-L (canine implants placed with lingual inclination). Results: Peri-implant bone stress levels associated with overdentures retained by lateral incisor implants resulted in the lowest stress levels and the highest efficiency in distributing peri-implant stress. MI-Hi showed increased stress levels and decreased efficiency in stress distribution. As the implants were inclined, stress levels increased and the efficiency of stress distribution decreased. Among the inclined models, MC-B showed the lowest stress level and best efficiency in stress distribution. Conclusion: The lowest stress and the best stability of implants in mandibular two-implant overdentures were obtained when implants were inserted in lateral incisor areas with shorter attachments and were placed parallel to the long axes of the teeth. [ABSTRACT FROM AUTHOR]

One of the fastest growing segments of implant dentistry is the utilization of computed tomography (CT) scan data and treatment planning software in conjunction with guided surgery for implant reconstruction cases. Computer assisted planning systems and associated surgical templates have established a predictable, esthetic, functional technique for placing and restoring implants. Especially, a philosophy of restoratively driven implant placement has been generally adopted. Recently, a variety of commercial dental fields have released their scanning and fabricating protocols and methods for restorations. This process is still being investigated and developed for the most precise and predictable outcome. This case report describes a female patient who wanted dental implants in fully edentulous areas. Restoratively driven implant placements were performed with surgical guide and the patient was fully satisfied with the clinical results, and at 5-year post restorative follow-up assessment, both implant and prosthesis were proved clinical success. [ABSTRACT FROM AUTHOR]

CAD/CAM technology has already been used in most areas of prosthetics. The range of CAD/CAM application in denture fabricating process has been gradually increasing since the CAD/CAM technology was introduced for the fabrication of complete dentures in 1994. This paper describes a technique that combines conventional and CAD/ CAM technology for the fabrication of complete dentures: the master casts from a conventional impression techniques were scanned first, and the wax denture was fabricated using Amann Girrbach's Ceramill full denture system (fds). The purpose of this paper is to introduce the case in which making an esthetically and functionally satisfied denture in shorter time is possible with CAD/CAM technology. [ABSTRACT FROM AUTHOR]

PURPOSE. The accuracy of denture bases was compared among injection molding, milling, and rapid prototyping (RP) fabricating method. MATERIALS AND METHODS. The maxillary edentulous master cast was fabricated and round shaped four notches were formed. The cast was duplicated to ten casts and scanned. In the injection molding method, designed denture bases were milled from a wax block and fabricated using SR Ivocap injection system. Denture bases were milled from a pre-polymerized block in the milling method. In the RP method, denture bases were printed and post-cured. The intaglio surface of the base was scanned and surface matching software was used to measure inaccuracy. Measurements were performed between four notches and two points in the mid-palatal suture to evaluate inaccuracy. The palatine rugae resolution was evaluated. One-way analysis of variance was used for statistical analysis at a=.05. RESULTS. No statistically significant differences in distances among four notches (P>.05). The accuracy of the injection molding method was lower than those of the other methods in two points of the mid-palatal suture significantly (P<.05). The degree of palatine rugae resolution was significantly higher in the injection molding method than that in other methods (P<.05). CONCLUSION. The overall accuracy of the denture base is higher in milling and RP method than the injection molding method. The degree of fine reproducibility is higher in the injection molding method than the milling or RP method. [ABSTRACT FROM AUTHOR]

PURPOSE. The design of the attachment must provide an optimum stress distribution around the implant. In this study, for implant overdentures with a bar/clip attachment or a locator attachment, the stress transmitted to the implant in accordance with the change in the denture base length and the vertical pressure was measured and analyzed. MATERIALS AND METHODS. Test model was created with epoxy resin. The strain gauges made a tight contact with implant surfaces. A universal testing machine was used to exert a vertical pressure on the mandibular implant overdenture and the strain rate of the implants was measured. RESULTS. Means and standard deviations of the maximum micro-deformation rates were determined. 1) Locator attachment: The implants on the working side generally showed higher strain than those on the non-working side. Tensile force was observed on the mesial surface of the implant on the working side, and the compressive force was applied to the buccal surface and on the surfaces of the implant on the non-working side. 2) Bar/clip attachment: The implants on the both non-working and working sides showed high strain; all surfaces except the mesial surface of the implant on the non-working side showed a compressive force. CONCLUSION. To minimize the strain on implants in mandibular implant overdentures, the attachment of the implant should be carefully selected and the denture base should be extended as much as possible. [ABSTRACT FROM AUTHOR]

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Fabricating a surveyed prosthesis beneath an existing partial removable dental prosthesis (PRDP) is a challenging and time-consuming procedure. The computer-aided design/computer-assisted manufacturing (CAD/CAM) technology was applied to fabricate a retrofitted, surveyed zirconia prosthesis to an existing PRDP. CAD/CAM technology enabled precise and easy replication of the contour of the planned surveyed crown on the existing abutment tooth. This technology ensured excellent adaptation and fit of newly fabricated crown to the existing PRDP with minimal adjustments. In this case report, a seventy-year-old male patient presented with fractured existing surveyed crown. Because the existing PRDP was serviceable, new crown was fabricated to the existing PRDP. [ABSTRACT FROM AUTHOR]

PURPOSE. The purpose of this study was to investigate the demographic patterns of maxillofacial prosthetic treatment to identify the characteristics and geographic distribution of patients with maxillofacial prosthetics in the capital region of Korea. MATERIALS AND METHODS. This retrospective analytical multicenter study was performed by chart reviews. This study included patients who visited the department of prosthodontics at four university dental hospitals for maxillofacial prosthetic rehabilitation. Patients with facial and congenital defects or with insufficient medical data were excluded. The patients were classified into three categories based on the location of the defect. Patients' sex, age, and residential area were analyzed. Pearson's chi-square test with a significance level of 0.05 was used to analyze the variables. RESULTS. Among 540 patients with maxillofacial prosthetics, there were 284 (52.59%) male patients and 256 (47.41%) female patients. The number of the patients varied greatly by hospital. Most patients were older than 70, and the most common defect was a hard palate defect. Chi-square analysis did not identify any significant differences in sex, age, and distance to hospital for any defect group (P>.05). CONCLUSION. The results of this study indicated that there was imbalance in the distribution of patients with maxillofacial prosthetic among the hospitals in the capital region of Korea. Considerations on specialists and insurance policies for the improvement of maxillofacial prosthetics in Korea are required. [ABSTRACT FROM AUTHOR]

Russell-Silver syndrome (RSS) is a congenital disease characterized by short stature due to growth hormone deficiency, physical asymmetry, inverted triangular face, micrognathia, prominent forehead, and hypodontia. This case report presents a prosthetic management of a 6-year-old patient with Russell-Silver syndrome treated with overdentures on the maxilla and the mandible using the remaining primary teeth. Subsequent and comprehensive dental management considering the growth and development of a young patient will be necessary. [ABSTRACT FROM AUTHOR]

This article presents the application of laser welding technique to fabricate an orthodontic mini-implant provisional restoration in missing area after limited orthodontic treatment. A 15-year-old boy case is presented. Two-piece orthodontic C-implant was placed after regaining space for missing right mandibular central incisor. Due to angular deviation of implant, customized abutment was required. Ready-made head part was milled and lingual part of customized abutment was made with non-precious metal. Two parts then were laser welded (Master 1000, Elettrolaser Italy, Verona, Italy) and indirect lab composite (3 M ESPE Sinfony, St. Paul, MN, USA) was built up. The patient had successful result, confirmed by clinical and radiographic examinations. Before the patient is ready to get a permanent restoration later on, this provisional restoration will be used. This case shows that a two-piece orthodontic C-implant system can be used to maintain small edentulous space after orthodontic treatment. [ABSTRACT FROM AUTHOR]

In case of missing of permanent teeth by trauma or innate defect, the decision of treatment modalities and application timing have an important effect on the prognosis of oral rehabilitation. In this case report, interdisciplinary approach between the orthodontic and prosthodontic treatment, the way to re-establish the collapsed occlusal vertical dimension, and implant prosthetic considerations will be discussed. Proper diagnosis on teeth and craniofacial skeleton was made prior to treatment and provisional restorations were used in regard of growth patterns of the patient. Finally, the edentulous areas were restored with fixed implant prostheses. Diagnosis, treatment rationale and prognosis will be discussed thoroughly. [ABSTRACT FROM AUTHOR]

Data collection including checking the problem list and analyzing the etiology cannot be overemphasized in full mouth rehabilitation cases. It is well reported that favorable prognosis of prosthodontic treatment depends on accurate diagnosis. Seventy seven year old female patient presented with chief complaints of chewing pain on maxillary and mandibular left premolars and unesthetic existing prosthesis. Clinical evaluation, radiographic examination and cast analysis were performed to gather comprehensive data and problem lists. Treatment planning was based on collected data and related articles. Abutment evaluation, prognosis depending on various types of prosthesis, and maintenance were considered as well. Occlusal vertical dimension was increased to solve esthetic dissatisfaction and insufficient interocclusal space. Patient adaptation was verified with provisional restorations followed by diagnostic wax up. Function, esthetics and occlusal stability were verified during 8 week follow-up period. Prosthodontic reconstruction based on systemic analysis, diagnosis, and treatment plan led to satisfactory result after delivery of definitive prosthesis. [ABSTRACT FROM AUTHOR]