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Context: Color difference between maxillar and mandibular incisors is an anticipated subject, and it will help dentists during color matching. Aim: The aim of this study was to evaluate color differences of the maxillar and mandibular incisors and to find out relationships between gender and age. Materials and Methods: This study was conducted on 125 participants (51 males and 74 females) between 16-63 age groups and totally over maxillar and mandibular 480 healthy teeth by using spectrophotometer. Color differences between teeth were calculated by using ∆E formula. One way ANOVA statistical analysis determined statistically significant differences between maxiller-central and mandibular-canine teeth for ∆L and ∆b parameters ( P <0.05). Results: According to t-test result there were not a statistically significant color differences for women and men teeth ( P <0.05). Scheffe statistical analysis results showed statistically significant differences between mandibular central and mandibular canine for ∆L parameters on 16-27, 28-39, and 52-63 age groups; for ∆b parameters, there were statistically significant differences between 16-27 and 40-51 age groups ( P <0.05). Conclusion: Women have more lighter teeth than men. Maxillar canines are more yellow and Maxillar centrals are more lighter than other incisors. 16-27, 28-39 age groups have more lighter teeth than 52-63 age groups and 16-27 age groups have more yellow teeth than 40-51 age groups.

Background Fracture or chipping are major concerning failures of an all-ceramic restoration. Repairing of the failure restoration using intra-oral technique is time saving and cost effective treatment modality. The present study was proposed to evaluate effect of Er,Cr:YSGG laser irradiation on shear bond strength between zirconia/porcelain and composite resin. Methods Thirty zirconia and thirty zirconia based porcelain disc shape specimens were prepared. Three different surface treatment procedure were applied the specimens. For control groups (Group ZC and PC), instruction manual of an intra-oral porcelain repair system was followed. Different pulse rates of Er,Cr:YSGG laser irradiation (short and long pulses) were applied to zirconia and porcelain surfaces for other groups (Group ZS, ZL, PS, and PL). Porcelain repair kit was used to repair specimens using standard cylindrical teflon mold (2 × 2 mm). Repair bond strength of the repaired specimens was tested using a universal testing machine. Results Highest mean bond strength value was observed at Group PC that was significantly higher than laser applied porcelain groups. Long pulse laser irradiation illustrated that increased mean bond strength compared to short pulse application on to the porcelain surface. Laser applied zirconia groups showed better mean bond strength than Group ZC, but differences between the groups were not statistically significant. Conclusion Different modes of Er,Cr:YSGG laser irradiation enhanced repair bond strength of the composite resin to zirconia, but these were not significant. Following the instruction manual for surface treatment on the porcelain surface was better method than Er,Cr:YSGG laser surface conditioning.

PURPOSEThe purpose of this study was to compare the effect of a diode laser and traditional irrigants on the bond strength of self-adhesive cement.MATERIALS AND METHODSFifty-five incisors extracted due to periodontal problems were used. All teeth were instrumented using a set of rotary root canal instruments. The post spaces were enlarged for a No.14 (diameter, 1.4 mm) Snowlight (Abrasive technology, OH, USA) glass fiber reinforced composite post with matching drill. The teeth were randomly divided into 5 experimental groups of 11 teeth each. The post spaces were treated with the followings: Group 1: 5 mL 0.9% physiological saline; Group 2: 5 mL 5.25% sodium hypochlorite; Group 3: 5 mL 17% ethylene diamine tetra acetic acid (EDTA), Group 4: 37% orthophosphoric acid and Group 5: Photodynamic diode laser irradiation for 1 minute after application of light-active dye solution. Snowlight posts were luted with self-adhesive resin cement. Each root was sectioned perpendicular to its long axis to create 1 mm thick specimens. The push-out bond strength test method was used to measure bond strength. One tooth from each group was processed for scanning electron microscopic analysis.RESULTSBond strength values were as follow: Group 1 = 4.15 MPa; Group 2 = 3.00 MPa; Group 3 = 4.45 MPa; Group 4 = 6.96 MPa; and Group 5 = 8.93 MPa. These values were analysed using one-way ANOVA and Tukey honestly significant difference test (P<.05). Significantly higher bond strength values were obtained with the diode laser and orthophosphoric acid (P<.05). There were no differences found between the other groups (P>.05).CONCLUSIONOrthophosphoric acid and EDTA were more effective methods for removing the smear layer than the diode laser. However, the diode laser and orthophosphoric acid were more effective at the cement dentin interface than the EDTA, Therefore, modifying the smear layer may be more effective when a self-adhesive system is used.

Background Restoration of the teeth with extensive root canals with different post systems is a challenge for clinicians. Evaluation of these systems is important for clinical success. The aim of this study was to compare the fracture resistance and fracture mode of endodontically treated thin-walled teeth which restored with different post systems. Methods Eighty extracted and endodontically treated maxillary canines were divided into 4 groups (n = 20) and the thickness of the radicular dentin walls was reduced by using diamond burs. Each root was embedded in an autopolymerizing resin with a 0.25 mm layer of vinyl polysiloxane material to simulate the periodontal ligament. The subgroups were restored with one of the following post systems: only composite resin (Group 1), cast post (Group 2), glass-fiber post (Group 3), and I-TFC post (Group 4). The samples were subjected to a gradually increasing force (0,5 mm/min). The force required to fracture was recorded, and the data were analyzed with ANOVA, Tukey test's and Chi–Square test (p < 0.05). Results The highest fracture resistance was recorded for Group 2, followed by the Group 3, Group 4, and Group 1. Differences in the fracture resistance of teeth were significant among the groups (p < 0.05). The fracture resistance of Group 4 was significantly different than the other tested post systems (p < 0.05). Conclusions The lowest fracture resistance was recorded for Group 1, but among all post systems, Group 4 had the lowest fracture resistance. The fracture mode of the fiber posts (Radix and I-TFC posts) would permit repair of the tooth.

PURPOSEThe aim of this study was to evaluate the effects of repeated porcelain firing process on the corrosion rates of the dental alloys.MATERIALS AND METHODSCr-Co, Cr-Ni and Pd-Ag alloys were used for this study. Each metal supported porcelain consisted of 30 specimens of 10 for 7, 9 and 11 firing each. Disc-shaped specimens 10 mm diameter and 3 mm thickness were formed by melting alloys with a propane-oxygen flame and casted with a centrifuge casting machine and then with the porcelain veneer fired onto the metal alloys. Corrosion tests were performed in quintuplicate for each alloy (after repeated porcelain firing) in Fusayama artificial saliva solution (pH = 5) in a low thermal-expansion borosilicate glass cell. Tamhane and Sheffe test was used to compare corrosion differences in the results after repeated firings and among 7, 9 and 11 firing for each alloy. The probability level for statistical significance was set at α=0.05.RESULTSThe corrosion resistance was higher (30 mV), in case of 7 times firing (Commercial). On the other hand, it was lower in case of 11 times firing (5 mV) (P<.05).CONCLUSIONRepeated firings decreased corrosion resistance of Pd-Ag, Cr-Co and Cr-Ni alloys. The Pd-Ag alloy exhibited little corrosion in in vitro tests. The Cr-Ni alloy exhibited higher corrosion resistance than Cr-Co alloys in in vitro tests.

<p><strong>Objectives:</strong> The aim of this study was to assesment of normal color vision and color vision-deficient dentists success ratio on color evaluation.</p> <p><strong>Materials and Methods:</strong> Dentists who have minimum 3 years clinical experience and between 26-63 years old (n=90) were included for this study. Ishihara color blindness test was applied in all dentists before the test applying. Two pieces from each color totally 32 (13 mm x 2.4 mm) porcelain specimens were fabricated. There were 32 tabs were to be matched; the</p> <p>dentists were asked to mark the correct color code</p> <p><strong>Results:</strong> Success rate of matching colors of color blind dentists was 33.92% ratio. The ratio in color vision dentists was 60.09%. Normal color vision dentists showed highest degree in matching at A3.5, B3, C4, D2 colors. Color vision-deficient dentists were unsuccessful in matching A1, B1, C1, B2, D2, A3 colors.</p> <p><strong>Conclusions:</strong> Color vision-deficient dentists were less succesfull than normal color vision dentists in color matching.</p> <p><strong>Keywords: </strong>Dentist, color blind, color selection.</p><p> </p><p><strong>ÖZET</strong></p> <p><strong>Amaç: </strong>Bu çalışmanın amacı,<strong> </strong>renk körü ve renk körü olmayan diş hekimlerinin renk seçimindeki başarı oranlarının değerlendirilmesidir.</p> <p><strong>Gereç ve Yöntem:</strong> En az 3 sene klinik deneyimi olan, yaşları 26 ile 63 arasındaki diş hekimleri (n=90) çalışmaya dahil edilmiştir. Test uygulaması yapılmadan önce tüm bireylere İshihara renk körlüğü testi uygulanmıştır. Ivoclar Klasik renk skalası referans alınarak, her bir renkten 2 şer adet olmak üzere toplam 32 adet disk (13 mm x 2,4 mm) hazırlandı. Aynı renkte olan porselen örneklerin eşleştirilmesi istendi.</p> <p><strong>Bulgular:</strong> Renk körü olan hekimler renkleri eşleştirmede başarı oranı 33,92 % dir. Renk körü olmayan diş hekimlerinde ise bu oran 60,09% dur. Renk körü olmayan diş hekimleri renk eşleştirmesinde sırasıyla A3.5, B3, C4, D2 renklerinde yüksek oranda başarı sağlamışlardır. Renk körü olan hekimler ise A1, B1, C1, B2, D2, A3 renklerinin eşleştirmesinde başarılı olamamışlardır.</p> <p><strong>Sonuç:</strong> Renk körü olan hekimler renk seçiminde, renk körü olmayan hekimlere göre daha başarısız olmuşlardır.</p>

The aim of this study was to investigate the effects of different surface treatment methods on shear bond strength between composite resin and different levels of zirconia ceramic. Laser surface-conditioning procedures have been reported as effective method to increase repair bond strength of composite to zirconia ceramics. Detailed information of effects of Er,Cr:YSGG laser treatment with different pulse rates on the zirconia ceramics is lacking in the literature. 120 disc-shaped specimens were prepared including zirconia, veneering ceramic, and 50% veneering ceramic-50% zirconia surfaces. Four different surface treatments were applied to the specimens. These were grinding with diamond bur, sandblasting, and short and long pulse rates of Er,Cr:YSGG laser irradiation. An intraoral ceramic repair kit was used to repair specimens, and shear bond strength was performed on the composite resin to each specimen. The highest mean bond strength was seen in the veneering ceramic surface that was ground using a diamond bur, and the lowest mean bond strength value was observed in the same surface that was treated with long pulse laser irradiation. The sandblasting with alumina particles exhibited lower mean repairing bond strength among the rest of used methods in this study for the group which contained half of the veneering ceramic and half of the zirconia. Sandblasting and Er,Cr:YSGG laser using surface treatment procedures obtained appropriate bond strength for the group that included 50% veneering ceramic-50% zirconia, because of no significant differences observed among the applied surface conditioning methods in this group.