• The Journal of Advanced Prosthodontics
• /
• 제11권1호
• /
• pp.7-15
• /
• 2019

PURPOSE. The aim of this study was to identify the effects of three aesthetic restorative materials on the wear between tooth and restoration by a pin-on-disk manner. MATERIALS AND METHODS. Six aesthetic restorative materials were used to prepare disk specimens for wear test, which were Lava Zirconia as zirconia group, Vintage MP and Cerabien ZR as veneering porcelain group, Gradia Direct microhybrid composite containing prepolymerized fillers, Filtek Z250 microhybrid composite containing zirconia glass and colloidal silica particles, and Filtek Z350 nanocomposite as composite resin group. Vertical loss of the worn cusp, change of the surface roughness of the restoration materials, and the surface topography were investigated after wear test under 9.8-N contact load. RESULTS. The porcelain groups (Vintage MP and Cerabien ZR) caused the largest vertical loss of teeth when compared with those of the composite resin and zirconia groups, and Filtek Z250 microhybrid composite results in the second-largest vertical loss of teeth. The surface of Filtek Z350 nanocomposite was deeply worn out, but visible wear on the surface of the zirconia and Gradia Direct microhybrid composite was not observed. When the zirconia surface was roughened by sand-blasting, vertical loss of teeth considerably increased when compared with that in the case of fine polished zirconia. CONCLUSION. It was identified that microhybrid composite resin containing a prepolymerized filler and zirconia with reduced surface roughness by polishing were the most desirable restorative materials among the tested materials to prevent the two-body wear between aesthetic restorative material and tooth.

• Restorative Dentistry and Endodontics
• /
• 제44권4호
• /
• pp.41.1-41.13
• /
• 2019

Objectives: This paper presents a systematic review and meta-analysis of the effect of preheating on the hardness of nanofilled, nanoceramic, nanohybrid, and microhybrid resin composites. Materials and Methods: An electronic search of papers on MEDLINE/PubMed, ScienceDirect, and EBSCOhost was performed. Only in vitro studies were included. Non-English studies, case reports, clinical trials, and review articles were excluded. A meta-analysis of the reviewed studies was conducted to quantify differences in the microhardness of the Z250 microhybrid resin composite using the Comprehensive Meta-Analysis software. Results: Only 13 studies met the inclusion criteria for this systematic review. The meta-analysis showed that there were significant differences between the non-preheated and preheated modes for both the top and bottom surfaces of the specimens (p < 0.05). The microhardness of the Z250 resin composite on the top surface in the preheated mode (78.1 ± 2.9) was higher than in the non-preheated mode (67.4 ± 4.0; p < 0.001). Moreover, the microhardness of the Z250 resin composite on the bottom surface in the preheated mode (71.8 ± 3.8) was higher than in the non-preheated mode (57.5 ± 5.7, p < 0.001). Conclusions: Although the results reported in the reviewed studies showed great variability, sufficient scientific evidence was found to support the hypothesis that preheating can improve the hardness of resin composites.

• Restorative Dentistry and Endodontics
• /
• 제42권4호
• /
• pp.253-263
• /
• 2017

Objectives: The aim of the study was to evaluate the 5-year clinical performance of occlusal carious restorations using nanofill and microhybrid composites, in combination with 3-step etch-and-rinse adhesives, in patients who were going to commence orthodontic treatment. Materials and Methods: A total of 118 restorations for occlusal caries were conducted prior to orthodontic treatment. Occlusal restorations were performed both with Filtek Supreme XT (3M ESPE) and Filtek Z250 (3M ESPE) before beginning orthodontic treatment with fixed orthodontic bands. Restorations were clinically evaluated at baseline and at 1, 2, 3, 4, and 5-year recalls. Results: None of the microhybrid (Filtek Z250) and nanofill (Filtek Supreme XT) composite restorations was clinically unacceptable with respect to color match, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, or surface texture. A 100% success rate was recorded for both composite materials. There were no statistically significant differences in any of the clinical evaluation criteria between Filtek Z250 and Filtek Supreme XT restorations for each evaluation period. Conclusions: The composite restorations showed promising clinical results relating to color matching, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, and surface texture at the end of the 5-year evaluation period.

• Restorative Dentistry and Endodontics
• /
• 제43권2호
• /
• pp.26.1-26.12
• /
• 2018

Objective: The purpose of this study was to investigate the degree of conversion (DC) and mechanical properties of a microhybrid Filtek Z250 (3M ESPE) resin composite after aging. Method: The specimens were fabricated using circular molds to investigate Vickers microhardness (Vickers hardness number [VHN]) and DC, and were prepared according to ISO 4049 for flexural strength testing. The initial DC (%) of discs was recorded using attenuated total reflectance-Fourier transforming infrared spectroscopy. The initial VHN of the specimens was measured using a microhardness tester under a load of 300 g for 15 seconds and the flexural strength test was carried out with a universal testing machine (crosshead speed, 0.5 mm/min). The specimens were then subjected to thermocycling in $5^{\circ}C$ and $55^{\circ}C$ water baths. Properties were assessed after 1,000-10,000 cycles of thermocycling. The surfaces were evaluated using scanning electron microscopy (SEM). Data were analyzed using 1-way analysis of variance followed by the Tukey honest significant difference post hoc test. Results: Statistical analysis showed that DC tended to increase up to 4,000 cycles, with no significant changes. VHN and flexural strength values significantly decreased upon thermal cycling when compared to baseline (p < 0.05). However, there was no significant difference between initial and post-thermocycling VHN results at 1,000 cycles. SEM images after aging showed deteriorative changes in the resin composite surfaces. Conclusions: The Z250 microhybrid resin composite showed reduced surface microhardness and flexural strength and increased DC after thermocycling.

• 대한소아치과학회지
• /
• 제32권1호
• /
• pp.7-12
• /
• 2005

최근에 개발된 나노 충전제를 microhybrid 복합레진에 첨가할 때, 나노 충전제 함량이 중합에 미치는 영향을 조사하기 위해, 실험적으로 나노 충전제의 함량을 다르게 제작한 복합레진에서 광중합 후 미세경도를 측정, 분석하여 다음과 같은 결론을 얻었다. 1. 나노 충전제의 함량이 2%, 3%인 군은 0%, 1%인 군에 비해 중합된 면의 미세경도가 유의하게 높았으나(p<0.01), 그 차이는 크지 않았다. 2. 나노 충전제의 함량이 높을수록 레진 시편의 하면에서의 미세경도는 증가하였으며, 나노 충전제의 함량이 0%, 1%, 2%간에 0%, 1%, 3%간에 유의한 차이가 있었고(p<0.01), 2%와 3%간에는 차이가 없었다(p>0.05). 3. 레진 시편의 상면과 하면의 미세 경도 차이는 나노 충전제 함량이 높을수록 감소하였으며, 나노 충전제의 함량이 0%, 1%, 2%간에, 0%, 1%, 3%간에 유의한 차이가 있었고(p<0.01), 2%와 3%간에는 차이가 없었다(p>0.05).

• 구강회복응용과학지
• /
• 제31권4호
• /
• pp.294-300
• /
• 2015

목적: 저점도 벌크필레진과 복합레진을 적층한 수복물의 색조를 평가하기 위함이다. 연구 재료 및 방법: 저점도 벌크필레진(SDR)과 A2, A3 색조의 미세혼합형 복합레진(A2, A3)을 4 mm 두께로 제작하여 광중합한 후 색차계를 이용하여 레진 시편의 CIE $L^*a^*b^*$ 값을 측정하였다. 이후 저점도 벌크필레진 상방에 2 mm 두께로 A2, A3 색조의 미세혼합형 복합레진을 적층하여(SA2, SA3) 광중합한 후 색측정을 하고(n = 10), 저점도 벌크필레진과 미세혼합형 복합레진, 그리고 이들을 적층한 시편의 색차(${\Delta}E$)를 계산하였다. 결과: $L^*$ 값은 SDR이 가장 컸고 SA2, SA3 그리고 A2, A3 순으로 감소했다. $a^*$ 값은 SDR이 가장 작았고 SA2, SA3 그리고 A2, A3 순으로 증가했다. $b^*$ 값은 SDR이 가장 작았으며 A2, SA2 그리고 A3, SA3 순으로 증가했다. 적층한 시편과 미세복합형 복합레진 시편의 ${\Delta}E$ 값은 A2와 SA2 사이에 ${\Delta}E=3.4$, A3와 SA3 사이에 ${\Delta}E=3.1$로 계산되었다. 결론: 저점도 벌크필레진과 미세혼합형 복합레진을 적층한 시편과 미세혼합형 복합레진만으로 제작한 시편의 색조의 차이는 일반적으로 인지하지 못할 정도로 작았다.

• 대한소아치과학회지
• /
• 제43권3호
• /
• pp.275-283
• /
• 2016

본 연구는 복합레진의 연마방법에 따른 표면특성을 평가하기 위해, microhybrid 레진(Filtek$^{TM}$ Z250)과 nanofill 레진(Filtek$^{TM}$ Z350)을 연마 전, abrasive disk(Sof-lex) 연마 후, polishing brush(Occlubrush) 연마 후로 나누어 분석하였다. 그 결과 레진 표면조도는 연마 후 증가하였는데, 미세조도는 연마방법에 따른 차이가 없었으나 거시조도는 Occlubrush를 이용한 경우 현저하게 커졌다(p < 0.05). Sof-lex 연마의 경우 레진의 filler까지 연마되어 표면이 보다 균일한 형상을 보였으나 Occlubrush 연마시편은 기질층이 뜯겨져 나간 불균일한 형상을 보였다. 두 연마방법 간의 미세경도 유의차는 없었으며(p > 0.05), 연마 후 경도 값이 약 25% 상승하였다. 결론적으로, 복합레진의 표면경도 향상을 위하여 적합한 연마가 필요하며, Sof-lex를 이용한 연마가 더 우수한 것으로 사료된다.

• Restorative Dentistry and Endodontics
• /
• 제33권5호
• /
• pp.457-462
• /
• 2008

중합수축이 일어난 후 복합 레진 내에는 중합수축에서 기원한 응력이 내부에 남아있을 수 있는데 이를 "잔류응력"이라 한다. 수복물에 가해지는 총힘은 외부에서 가해지는 힘과 내부에 남아있는 응력의 합으로 결정이 되며 수복물의 실패를 이해하기 위해서 이 두 가지 요소가 반드시 고려되어야 한다. 본 연구에서는 ring slitting방법을 이용하여 최근 임상에 소개된 나노충진형 복합레진간의 잔류응력을 비교하였다. 실험에 사용한 복합레진은 대조군으로 microhybrid-type인 Z250과 nanofiller를 함유한 Grandio, Filtek Supreme, Ceram-X를 이용하여 복합레진 링을 제작하고 2개의 기준점을 표시한 후 이 사이의 거리를 링 절단 전과 후에 각각 측정하여 거리 변화를 측정하였다. 거리의 변화로부터 average circumferential residual stress $({\sigma}{\theta})$를 계산하였다. 10분과 1시간 경과 후 측정한 군에서는 Filtek Supreme이 Z250이나 Ceram-X보다 높은 잔류응력을 보여 주었고, 24시간 경과한 군에서는 Filtek Supreme이 나머지 군보다 높은 잔류응력을 보여주었다. 본 실험 결과에 의하면 nanofiller를 함유한 복합레진의 잔류응력은 대조군으로 사용한 Z250보다 높거나 같은 값을 나타냈으며 거의 비슷한 기질조성을 가진 Z250과 Filtek Supreme을 비교했을 때 Filtek supreme이 모든 측정시간대에서 높은 잔류응력을 보여주었다.

• 대한치과보철학회지
• /
• 제38권3호
• /
• pp.366-374
• /
• 2000

FRC/ceromer system provides the clinician with a durable, flexible, and esthetic alternative to conventional porcelain fused to metal crowns. FRC is the matrix which is silica-coated and embedded in a resin matrix. The ceromer material which is a second generation indirect composite resin contains silanized, microhybrid inorganic fillers embedded in a light-curing organic matrix. FRC/ceromer restoration has a several advantages: better shock absorption, less wear of occluding teeth, translucency, color stability, bonding ability to dental hard tissues, and resiliency. It has versatility of use including inlay, onlay, single crown, and esthetic veneers. With adhesive technique, it can be used for single tooth replacement in forms of inlay adhesion bridge. In single tooth missing case, conventional PFM bridge has been used for esthetic restoration. However, this restoration has several disadvantages such as high cost, potential framework distortion during fabrication, and difficulty in repairing fractures. Inlay adhesion bridge with FRC/ceromer would be a good alternative treatment plan. This article describes a cases restored with Targis/Vectris inlay adhesion bridge. Tooth preparation guide, fabrication procedure, and cementation procedure of this system will be dealt. The strength/weakness of this restoration will be mentioned, also. If it has been used appropriately in carefully selected case, it can satisfy not only dentist's demand of sparing dental hard tissue but also patient's desire of seeking a esthetic restorations with a natural appearance.

• 대한치과의사협회지
• /
• 제56권6호
• /
• pp.314-322
• /
• 2018

Among developmental anomalies of tooth shape, fusion and gemination are comparatively common. Developed with different etiologies, both fusion and gemination show similar clinical features. Therefore, many clinicians have difficulty diagnosing those morpho-anatomic anomalies. The purpose of this study is to report malformed right maxillary first molar in a 20-year-old female. With the aid of computed tomography (CT), the tooth was diagnosed as fusion with supernumerary tooth and dental caries lesion was detected. After performing direct pulp capping, the tooth was permanently restored with microhybrid composite resin using direct method to alter union groove into smooth surface for improving oral hygiene management. Until 6 months of follow-up visits, patient's chief complaint was resolved and tooth is still vital. In conclusion, identifying exact anatomy, conservative treatment and improving oral hygiene are essential in managing unusual morphologic anomalies of tooth.