• The Journal of Advanced Prosthodontics
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• v.10 no.4
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• pp.321-327
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• 2018

PURPOSE. The purpose of this study was to compare the cutting method and the lamination method to investigate whether the CAD data of the proposed inlay shape are machined correctly. MATERIALS AND METHODS. The Mesial-Occlusal shape of the inlay was modeled by changing the stereolithography (STL). Each group used SLS (metal powder) or SLA (photocurable resin) in the additive method, and wax or zirconia in the subtractive method (n=10 per group, total n=40). Three-dimensional (3D) analysis program (Geomagic Control X inspection software; 3D systems) was used for the alignment and analysis. The root mean square (RMS) in the 2D plane state was measured within $50{\mu}m$ radius of eight comparison measuring points (CMP). Differences were analyzed using one-way analysis of variance and post-hoc Tukey's test were used (${\alpha}=.05$). RESULTS. There was a significant difference in RMS only in SLA and SLS of 2D section (P<.05). In CMP mean, CMP 4 ($-5.3{\pm}46.7{\mu}m$) had a value closest to 0, while CMP 6 ($20.1{\pm}42.4{\mu}m$) and CMP 1 ($-89.2{\pm}61.4{\mu}m$) had the greatest positive value and the greatest negative value, respectively. CONCLUSION. Since the errors obtained from the study do not exceed the clinically acceptable values, the lamination method and the cutting method can be used clinically.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.702-709
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• 1997

To compare the marginal leakage of CAD/CAM-fabricated ceramic inlay, gold inlay and amalgam, forty extracted caries-free premolars were prepared with Class II MO cavity design. The teeth were divided into four groups of ten samples each. Group 1 was restored with CAD/CAM-fabricated ceramic inlays cemented with Scotchbond Resin Cement / Scotchbond Multi-purpose plus. Group 2 was restored with gold inlays cemented with Scotchbond Resin Cement / Scotchbond Multi-purpose plus. Group 3 was restored with gold inlays cemented with zinc phosphate cement. And, Group 4 was restored with amalgam. All samples were thermocycled, and stored in 1 % methylene blue. Marginal leakage was examined at four margins, that is, occlusal distal, priximal gingival, occlusal facial and occlusal lingual margins from sectioned samples under stereomicroscope(x15). The results were as follows : 1. Group 1 and 2 showed no statistically significant difference among marginal leakage at all four examined margins(p>0.05). 2. Group 3 and 4 showed significant marginal leakage at proximal gingival margin compared with other margins(p<0.05). 3. Significantly increased marginal leakage at priximal gingival, occlusal facial and occlusal lingual margins in group 3 were observed compared with other groups (p<0.05).

• Restorative Dentistry and Endodontics
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• v.26 no.6
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• pp.464-484
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• 2001

When restoring a tooth, the dentist tries to choose the ideal material for existing situation. One criterion that is considered is its suitability for restoring coronal strength. As more tooth structure is removed, the cusps are weakened and susceptible to fracture. Further, this increased deformation may cause the formation of intermittent gaps at the margin between the hard tissue and the restoration, facilitating marginal leakage. The improvements in ceramic materials now make it possible for alternatives to amalgams, composites, and cast metal to be of offered for posterior teeth. Of the materials used, ceramics most closely approximates the properties of enamel. The introduction of computer-aided design/computer-aided manufacture(CAD/CAM) systems to restorative dentistry represents a major technological breakthrough. It is possible to design and fabricate ceramic restorations at a single appointment. Additionally, CAD/CAM systems eliminate certain errors and inaccuracies that are inherent to the indirect method and provide an esthetic restoration. The aim of this investigation was to study the loading characteristics of CAD/CAM ceramic inlay and to compare the stress distribution and displacement associated with different designs of cavity(the isthmus width and cavity depth). A human maxillary left first premolar was prepared with standard mesio-occlusal cavity preparation, as recommended by the manufacturer Ceramic inlay was fabricated with CEREC 2 CAD/CIM equipment and cemented into the prepared cavity. Three dimensional model was made by the serial photographic method. The cavity width was varied $\frac{1}{3}$, $\frac{1}{2}$ and $\frac{2}{3}$ of intercuspal distance between buccal and lingual cusp tip. The cavity depth was varied 1.5mm and 2.3mm. So six models were constructed to simulate six conditions. A point load of 500N was applied vertically onto the first node of the lingual slope from the buccal cusp tip. The stress distribution and displacement were solved using ANSYS finite element program(Swanson Analysis System). (omitted)

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.84-94
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• 1993

The purpose of this study was to evaluate flexure strength of composite resin inlay according to heat treatment and duration in comparasion with visible light-cured resin. In this study, materials were used 1 visible light-cured resin and 3 kinds of composite resin inlays. Control group was visible light cured resin (Photo Clearfil Posterior) and experimental groups were composite resin inlays (Brilliant Dentin, Brilliant Enamel and Clearfil CR Inlay). Experimental groups were divided 3 groups: First group was Brilliant Dentin and second group was Brilliant Enamel and -third group was Clearfil CR Inlay. Used experimental groups were calculated flexural strength according to heat treatment and duration. The following results were obtained: 1. Experimental groups were higher flexural strength than control group. 2. At $100^{\circ}C$ when heat treatment carried out 7 minutes flexural strength elevated third group, second group, first group in turn and when heat treatment carried out 15 minutes flexural strength elevated third group, second group, first group in turn but no difference was showed between first and second group. 3. At $125^{\circ}C$ when heat treatment was carried out 7 minutes flexural strength elevated third group, second group, first group in turn and when heat treatment was carried out 15 minutes flexural strength elevated third group, first group, second group in turn but no difference was showed between first and second group. 4. In spite of heat treatment and duration the third group was highest flexural strength in the others groups.

• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.64-72
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• 1994

Zinc Phosphate Cement hand been used for about more than 100 years in luting of cast gold inlay. But many scientists had been trying to develop the new form of luting agent because the ZPC hand shown the lack of adhesiveness on the tooth structure and the toxicity to the pulp tissue. Recently many researches about the surface treatment of the cast body are being done to increase the adhesion of cement to it. The conventional Class I gold inlays were fabricated in the 20 permanent molars. After the internal surface of the cast body was sandblasted with $Al_2O_3$ particles and was tin-plated, the inlays were cemented with adhesive cement [G I cement and resin cement(Super-Bond & $Panavia_{EX}$)] and the evaluation on the adhesion pattern, adhesive strength and the fracture pattern of the adhesive cast gold inlay was compared to that of the cast gold inlay cemented conventionally with ZPC. The results were as follows : 1. The surface roughness of the cast body was increased significantly after sandblasting with the $Al_2O_3$ particles and the tin oxide layer, which was consisted of round particles, came into being. 2. The bond strength was in the order of Super-Bond, ZPC, Fuji I, $Panavia_{EX}$ group. The group cemented with Super-Bond showed statistically greater strength than the other groups(p<0.05). 3. The group cemented with ZPC was fallen apart by principal adhesion failure and that with Fuji I was by complete adhesion failure. But the group with Super-Bond showed pricncipal cohesive failure pattern and in the group with $Panavia_{EX}$, complete cohesive fracture pattern was shown and small protion of tooth structure was fractured out with cast body and the fractured surface showed the figure just as the enamel prism. 4. Various gaps were shown at the pulpal side regardless of little gap at the side walls of the cavity in all groups. Only the Super-Bond was attached to the tooth structure and the other cements were detached from both the tooth and the cast body.

• The Journal of Advanced Prosthodontics
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• v.16 no.1
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• pp.57-65
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• 2024

PURPOSE. The aim of this stuldy was to compare the clinical marginal fit of CAD-CAM inlays obtained from intraoral digital impression or addition silicone impression techniques. MATERIALS AND METHODS. The study included 31 inlays for prosthodontics purposes of 31 patients: 15 based on intraoral digital impressions (DI group); and 16 based on a conventional impression technique (CI group). Inlays included occlusal and a non-occlusal surface. Inlays were milled in ceramic. The inlay-teeth interface was replicated by placing each inlay in its corresponding uncemented clinical preparation and taking interface impressions with silicone material from occlusal and free surfaces. Interface analysis was made using white light confocal microscopy (WLCM) (scanning area: 694 × 510 ㎛²) from the impression samples. The gap size and the inlay overextension were measured from the microscopy topographies. For analytical purposes (i.e., 95-%-confidence intervals calculations and P-value calculations), the procedure REGRESS in SUDAAN was used to account for clustering (i.e., multiple measurements). For p-value calculation, the log transformation of the dependent variables was used to normalize the distributions. RESULTS. Marginal fit values for occlusal and free surfaces were affected by the type of impression. There were no differences between surfaces (occlusal vs. free). Gap obtained for DI group was 164 ± 84 ㎛ and that for CI group was 209 ± 104 ㎛, and there were statistical differences between them (p = .041). Mean overextension values were 60 ± 59 ㎛ for DI group and 67 ± 73 ㎛ for CI group, and there were no differences between then (p = .553). CONCLUSION. Digital impression achieved inlays with higher clinical marginal fit and performed better than the conventional silicone materials.

• Restorative Dentistry and Endodontics
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• v.25 no.3
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• pp.399-406
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• 2000

The effect of inlay surface treatment on bonding was investigated when resin inlay was bonded to resin-modified glass-ionomer base with resin cement. For the preparation of glass-ionomer base, resin-modified glass-ionomer cement (Fuji II LC, GC Co., Japan) was filled in class I cavities of 7mm in diameter and 2mm in depth made in plastic molds. Eighty eight resin inlay specimens were made with Charisma$^{(R)}$ (Kulzer, Germany) and then randomly assigned to the four different surface treatment conditions: Group I, $50{\mu}m$ aluminium oxide sandblasting and silane treatment ; Group II, silane treatment alone ; Group III, sandblasting alone, and Group IV (control), no surface treatment. After a dentin bonding agent with primer (One-Step$^{TM}$, Bisco Inc., IL., U.S.A.) was applied to bonding surface of resin inlay and base, resin inlay were cemented to glass-ionomer base with a resin cement (Choice$^{TM}$, Bisco Inc., IL., U.S.A.). Shear bond strengths of each specimens were measured using Instron universal testing machine (4202 Instron, lnstron Co., U.S.A.) and fractured surfaces were examined under the stereoscope. Statistical analysis was done with one-way ANOVA and Dunkan's multiple range test. The results were as follows: 1. Sandblasting and silane treatment provided the greatest bond strength(10.56${\pm}$1.95 MPa), and showed a significantly greater bond strength than sandblasting alone or no treatment (p<0.05). 2. Silane treatment provided a significantly greater bond strength(9.77${\pm}$2.04 MPa) than sandblasting alone or no treatment (p<0.05). However, there was no significant difference in bond strength between sandblasting treatment and silane one (p>0.05). 3. Sandblasting alone provided no significant difference in bond strength from no treatment (p>0.05). 4. Stereoscopic examination of fractured surface showed that sandblasting and silane treatment or silane treatment alone had more cohesive failure mode than adhesive failure mode. 5. In relationship between shear bond strength and failure mode, cohesive failure occurred more frequently as bond strength increased.

• Journal of the Korean Arthroscopy Society
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• v.2 no.1
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• pp.1-3
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• 1998

The PCL reconstruction in chronic isolate PCL reconstruction was still controversy. 1) In isolate PCL deficient knee, functionally not so bad as like ACL deficient knee. 2) The result of the PCL reconstruction was not as good as ACL reconstruction. Therefore, isolate PCL injuries has been treated as nonoperatively. Hey Grovere, who was the first to attempt an intra-articular reconstruction of the PCL, utilized the semi-tendinous tendon other static procedures have been described in only a few cases with very limited follow-up. Dynamic procedures utilizing the medial head of the gastrocnemius has been reported by Hugston and Degenhardt, Kennedy and Grainger, and Insall and Hood. These procedures did not improve static stability. Dr Clancy, who was introduce the use of BPTB for the PCL reconstruction transtibial and femoral tunnel. From 1995, untill early 1990 PCL reconstruction was done as tend as placement of the isometric point. Physiometic placement of Anatomical placement of the femoral tunnel in PCL reconstruction were introduced in 1995. Tibial Inlay Technique was reported by Dr Berg in 1995. The main advantage of the tibial Inlay Technique was to avoid fraying of the graft at the posterior tibial tunnel orifice. In complete PCL ruptured and severely posterior unstable knee, dual femoral tunnel technique will be to get better result than one bundle technique. To achieve restoration of normal posterior laxity, it is critical to address the posterior as well as the posterolateral structures. Futher research is necessary to evaluate new surgical approches such as double-bundle reconstructions and tibial inlay techniques as well as improved techniques for capsular and collateral ligament injuries.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.2
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• pp.127-132
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• 2005

Beginning the use of medical order with color contact lens, recently the color contact lens wearer increases for cosmetic order in the world. The marufacture of color contact lenses was the pigment application method, the pigment inlay method, the sandwich method, the vinding method, and so on. Now in domestic, the main use of manufacture has been the binding method. In the point of the use and manufacture of the color contact lenses, the classification of color contact lenses was the tinted and the cosmetic types. However the generally coloring of color contact lenses was the stain-method and the staining was marufactured by the thin film methods.

• The KIPS Transactions:PartA
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• v.12A no.6 s.96
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• pp.515-522
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• 2005

This paper presents a method for effectively modeling inlay/onlay prostheses restoring a tooth that are partially destroyed. An inlay/onlay is composed of internal surface adhering to an abutment, and external surface revealed to the outside sight. Internal surfaces are modeled using Minkowski sum expanding the grinded surface parts of abutments so that the internal surfaces can adhere to the abutments with closer contact. In modeling external surfaces, we exploit 3D mesh deformation techniques: DMFFD(direct manipulation free-form deformation)[19] and MWD(multiple wires deformation)[17] with three kinds of informations: standard teeth models, mesh data obtained by scanning a plaster cast of a patient's tooth, FGP(functionally guided plane) measuring the occlusion of the patients's teeth. The standard teeth models are used for building up the basic shapes of external surfaces, while the plaster fast and FGP data are used for reflecting the unique properties of adjacent md occlusal surfaces of the patients's teeth, which are slightly different to each other but very important for correct functioning. With these informations as input data, the adjacent and occlusal surfaces are automatically generated as mesh data using the techniques of DMFFD and m, respectively. Our method was implemented so that inlay/onlay prostheses fan be designed more accurately by visualizing the generated mesh models with requirements by dentists.