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The aim of this study is to investigate the stress distributions of different restoration options for class II mesio-occluso-distal (MOD) cavities. A class II MOD cavity with proximal box gingival floor 1 mm below cementoenamel junction was designed in a mandibular first molar tooth model. 3D finite-element analysis (FEA) and 3D-CAD modelling were used to examine the occlusal stresses distributed to the remaining buccal enamel (RBE), remaining lingual enamel (RLE), adhesive surfaces, and restorative materials by direct and indirect materials resulting from a 600 N of static occlusal load stimulating foodstuff. von Mises (VM) and maximum principal (Pmax) stresses were evaluated for two CAD/CAM materials and three direct materials. CAD/CAM materials exerted less stress than the direct restorative materials. Significant von Mises and Pmax stress value differences were seen among all restoration models on RBE. Reducing RLE and including it into the cavity would be a more effective option for this model in this scenario. As VM and Pmax stresses of PIHC CAD/CAM material for RBE and dentin were significantly lower than other tested materials, it may be the choice of material for indirect MOD restorations.

Objectives The aim of this study is to assess the stress distribution of a nanoceramic resin CAD/CAM material, Lava Ultimate (LU) and a polymer-infiltrated hybrid ceramic CAD/CAM material, Vita Enamic (VE) for enamel replacement for Nayyar core (corono-radicular dowel and core) or post-retained restoration designs of a maxillary first premolar tooth with missing palatal cusp. Materials and methods A three dimensional finite element (FE) modelof maxillary first premolar with two roots was modeled. A mesial-occlusal-distal-palatal (MODP) cavity was designed with cavity floor above cemento-enamel junction and including buccal cuspal reduction. Restoration designs consisted of Nayyar core restoration (NCR) and post-retained restoration (PRR) with a glass fiber post. Vita Enamic (VE), Lava Ultimate (LU) were used for enamel and everX Posterior was used for dentin replacement. Vertical occlusal load (100 N) was applied on a spherical solid rigid material simulating the food stuff. Von Mises (VM) and maximum principle stress values were evaluated separately for the remaining enamel, remaining dentin and restorative material in megapascal (MPa). Results The analysis of both VM and maximum principle stress values revealed that the most intense stress accumulation was in the cervical region of enamel for both designs. For VM, similar stress values were observed only in dentin. Stress analysis of restorative materials showed that everX Posterior had the highest stress accumulation. Conclusions The comparison of the two techniques showed that PRR had better stress distribution than NCR. NCR or PRR with LU or VE exhibited similar VM stress accumulation in dentin. Maximum principle stress analyses showed that PRR with LU transmitted the least stress to enamel and dentin indicating that when LU is the material of choice, post-retained restoration would be a satisfactory design. VM stress values of enamel revealed that VE absorbed the stress in itself and transferred less stress to dentin. This could point out that for the restoration of maxillary first premolar tooth with missing palatal cusp, VE may be a suitable material for NCR and PRR restoration techniques. Highlights When fiber reinforced composite is used as dentin replacement in combination with VE as enamel replacement; any technique; PRR or NCR, may be preferred in the restoration of MODP cavities of endodontically treated maxillary premolars. The clinical relevance has to be further studied in-vivo.

Regeneration is reconstruction of a tissue with the shape and function of the original tissue including vascularization and innervations. Highly degradation of dentin-pulp complex can not be reversed by its own repair mechanisms. For decades, endodontic treatments including pulpectomy and preparation of root canals have been the first choice for these cases. However, root canal treatment method has some unsatisfying consequences like; esthetic problems as a conclusion of discoloration caused by endodontic filling materials, undermined integrity of tooth structure, postoperative fractures, coronal leakage or periapical microleakage, lost sense of environmental changes which can make the recurrent caries or apical infection unnoticeable for patient and shortened lifetime in comparison with vital teeth. Currently regeneration of dentin-pulp complex by tissue engineering approach is thought to be a more appropriate choice instead of root canal treatment according to these outcomes. In this review, we will discuss basic components as stem cells, signaling molecules and scaffolds and also methods used for dentin-pulp tissue engineering.

The aim of this study was to evaluate the effects of two endocrown designs and computer aided design/manufacturing (CAD/CAM) materials on stress distribution and failure probability of restorations applied to severely damaged endodontically treated maxillary first premolar tooth (MFP). Two types of designs without and with 3 mm intraradicular extensions, endocrown (E) and modified endocrown (ME), were modeled on a 3D Finite element (FE) model of the MFP. Vitablocks Mark II (VMII), Vita Enamic (VE), and Lava Ultimate (LU) CAD/CAM materials were used for each type of design. von Mises and maximum principle values were evaluated and the Weibull function was incorporated with FE analysis to calculate the long term failure probability. Regarding the stresses that occurred in enamel, for each group of material, ME restoration design transmitted less stress than endocrown. During normal occlusal function, the overall failure probability was minimum for ME with VMII. ME restoration design with VE was the best restorative option for premolar teeth with extensive loss of coronal structure under high occlusal loads. Therefore, ME design could be a favorable treatment option for MFPs with missing palatal cusp. Among the CAD/CAM materials tested, VMII and VE were found to be more tooth-friendly than LU.

The aim of this study was to investigate the effect of hydrogen peroxide (HP) and carbamide peroxide (CP) on the surface roughness of five different composite resins using profilometer and scanning electron microscope (SEM). Thirty-six specimens (1 mm thick, 10 mm in diameter) of five composite resins were fabricated. Each composite group was equally divided into three subgroups as control, CP and HP. In control group, specimens were stored in daily refreshed distilled water during the 14-day testing period. In other groups, 10% HP (Opalescence Treswhite) and 10% CP (Opalescence PF) were applied and surface roughness values (Ra) of each specimen were measured with a profilometer at the end of 14 days. Additionally, SEM analysis was performed to evaluate the surface deformations of composite resins. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Ra values of composite groups exposed to bleaching agents were statistically higher than control group (p

Objectives: This study aimed to compare the translucency characteristics of different shades of 5 composites. Methods: Seven resin discs were prepared from each composite (Grandio, Gradia Direct, Clearfil Majesty Esthetic, Ceram-X Mono, Filtek Z250) and shade (A1, A2, A3). Baseline CIE L*a*b* color coordinates of specimens were measured in a viewing booth with D65 illumination by spectrophotometer (Easyshade Compact, Vita). The translucency parameter was calculated for each specimen. Results were analyzed statistically. Results: Grandio and Gradia were significantly more translucent than Clearfil Majesty Esthetic, Ceram-X Mono and Filtek Z250 for A1 shade. For A2 shade, TP values of Grandio, Gradia and Clearfil Majesty Esthetic were statistically higher than Filtek Z250 and Ceram-X Mono. For A3 shade, Grandio was statistically the most translucent resin among all composites. There was no statistical difference between TP values of Clearfil Majesty Esthetic, Gradia and they were significantly more translucent than Filtek Z250 and Ceram-X Mono for A3 shade (p

Background Air-drying of etched and rinsed dentin surface may force the exposed collagen fibrils to collapse. Blot-drying is an alternative method to wipe the excess water from the dentin surface without compromising the monomer penetration. Contemporary total etch adhesives contain ethanol/water or acetone as solvent in which resin monomers are dissolved. Solvent type of the adhesive system has an important role in bonding to dentin. An adhesive containing tertiary butanol as an alternative solvent has been in the market. Purpose of this study is to determine the shear bond strengths of three total-etch adhesives with different solvents (acetone, ethanol or tertiary butanol) applied to air or blot dried moist dentin. Methods Sixty extracted non-carious human third molars were divided into three main groups according to solvent content of the adhesives [acetone based - One Step (OS, Bisco, IL, USA); ethanol/water based - Optibond Solo Plus (OB, Kerr, CA, USA); and tertiary butanol based - XP Bond (XP, Caulk/Dentsply, DE, USA)]. Each main group was divided into two groups according to drying methods (blot or air) (n = 10). Shear bond strengths (SBS) were measured. Data were analyzed by Student’s t test and Tukey HSD test (p 0.05). XP-blot produced significantly higher SBS than XP-air (p

To evaluate the microshear bond strength of tri-calcium silicate-based materials to different restorative materials.Thirty-five disks of TheraCal LC and Biodentine were fabricated using teflon molds according to manufacturers' instructions. Then the specimens were randomly divided into 7 groups according to the materials applied: Fuji IX, Fuji II, Equia Fil, Vertise Flow, Filtek Bulk Fill Posterior Restorative, Filtek Z250 with PrimeBond NT and with Clearfil SE Bond. All restorative materials were placed onto the disks using tygon tubes. Following a storage period, the specimens underwent microshear bond strength testing in a universal testing machine, and fracture modes were analyzed. Data were analyzed using one-way ANOVA and Tukey's post-hoc test.For all restorative materials, TheraCal LC showed significantly higher μSBS values compared to Biodentine. GIC based materials showed the lowest μSBS for TheraCal and Biodentine. For Biodentine, Filtek Z250 applied with PrimeBond NT and Filtek Bulk Fill Posterior Restorative applied with Scotchbond Universal Adhesive exhibited the highest μSBS, while Filtek Z250 applied with Clearfil SE Bond revealed the highest bond strength to TheraCal LC.For all restorative materials tested in this study, TheraCal LC showed higher μSBS compared to Biodentine. For both TheraCal LC and Biodentine, the placement of GIC-based materials prior to composite resin restorations might decrease the bond strength. Composite resins applied with self-etching adhesives increased the bond strength of TheraCal LC; however, for Biodentine, application of etch-and-rinse adhesives may improve the adhesion of composite resins.

The purpose of this study was to evaluate the effect of Er,Cr:YSGG laser irradiation and/or acid etching on the micro-shear bond strength (µSBS) of two different dual-cured resin cements to human enamel. 24 intact, extracted molars were sectioned longitudinally and randomly divided into three subgroups according to three surface pretreatment methods: (1) Er,Cr:YSGG laser (Waterlase MD, Biolase) irradiation was used with a power setting of 2 W (55% water and 65% air), and a repetition rate of 20 Hz for 10 s; (2) 37% phosphoric acid application for 20 s; (3) Re-etching with phosphoric acid for 20 s after the Er,Cr:YSGG laser irradiation as in group1. 12 enamel discs for each of the resin cements (Panavia F2.0 and Variolink N) were prepared and three cylinders of resin cements were bonded to each enamel surface (n = 12). A micro-shear bond test (EZ-test- 500 N) was used at a cross-head speed of 1 mm min−1 to determine the µSBS. One-way analysis of the variance and Tukey post-hoc tests at the 95% confidence level were used to analyze the µSBS values. Panavia F2.0 verified significantly higher µSBS values than Variolink N (p < 0.05) for all the tested surface pretreatment methods. The combination of laser and acid etching on enamel produced higher µSBS values for bonding both resin cements than the use of acid or laser irradiation alone. The combination of the Er,Cr:YSGG laser and phosphoric acid etching of the enamel for the cementation of indirect restorations with Variolink N and Panavia F2.0 produced better µSBS values to enamel than the use of phosphoric acid or Er,Cr:YSGG laser etching alone, holding the potential to become a highly attractive method for routine use.

OZE T Gun gectikce gelisen teknoloji, dogada meydana gelen olaylarin molekuler duzeyde incelenmesi icin bilim dunyasina olanaklar sunmaktadir. Yirmi birinci yuzyila girilmesiyle birlikte stratejik onemi bir o kadar daha artmis olan nanoteknoloji; materyallerin atomik veya molekuler duzeyde manipule edilmesiyle mikroskopik aletler uretme sanatidir. Nanoolcek duzeyde mudahaleyi mumkun kilan bu teknoloji; saglikta arastirma, koruma ve iyilestirme alanlarinda insanligin yeni bir atilim yapmasina katki sunmaktadir. Bilim ve teknolojideki bu gelismeler dis hekimligiyle iliskili doku muhendisliginde, implantolojide, protetik dis tedavisinde ve restoratif dis tedavisinde yaygin olarak kullanilmaktadir. Ozellikle rezin bazli kompozit teknolojisi restoratif dis hekimliginde suren arastirmalar ve uygulanacak tedavilerde cigir acan bir gelisme olmustur. Nanoteknoloji alanindaki gelismeler surdukce restoratif dis hekimligi alaninda da yeni ufuklar acilmaya devam edecektir. Anahtar Kelimeler: Nanoteknoloji, nanokompozit, nanodoldurucu NANOTECHNOLOGY IN RESTORATIVE DENTISTRY ABSTRAC T The progression of technology provides opportunity to investigate the natural events in the molecular level. Its strategic value has been increased in the twenty-first century since it is; “the art of manipulating materials on an atomic or molecular scale especially to build microscopic devices”. As an enabling technology; the application of nanotechnology has the potential to contribute research, prevention and healing in health sciences. Especially these developments in science and technology are widely used in tissue engineering regarding dentistry, implantology, prosthetics and restorative treatment. Resin-based composite technology has been counted as breaking new ground in researches and treatments in restorative dentistry. As long as nanotechnology develops; new expansions will continue in restorative dentistry. Keywords : Nanotechnology, nanocomposite, nanofiller.

Gunumuzde modern dis hekimligi kapsaminda, dis dokularinin maksimum oranda korunmasi ve fonksiyon gormesi icin minimal invaziv yontemler uygulanmaktadir. G.V. Black tarafindan tanimlanmis olan geleneksel goruse bagli kalinarak uygulanan derin dentin curugu tedavilerinde tum curuk dokunun uzaklastirilmasi, pulpanin perforasyonuna dolayisiyla endodontik girisimlere ve bazi durumlarda cekime neden olabilmektedir. Disin agizda kalma suresi, fonksiyonu ve prognozu acisindan onemli bir etken olan pulpanin vitalitesinin daha uzun sure korunabilmesi amaciyla adeziv sistemler ve restoratif materyallerdeki yeni gelismelerle gunumuzde pek cok yeni tedavi yaklasimi ve materyal gelistirilmistir. Bu derlemede derin dentin curugu varliginda curugun uzaklastirilmasindaki selektif yaklasimlar, kavitenin dezenfeksiyonu, kuafaj uygulamalari ve derin dentin curugunun tedavisindeki guncel yaklasimlar tartisilmistir. Anahtar Kelimeler : Asamali Curuk Tedavisi, Derin Dentin Curugu, Dezenfeksiyon, Selektif Yaklasimlar ALTERNATIVE NEW METHODS FOR THE TREATMENT OF DEEP DENTINE CARIES ABSTRACT Currently minimal intervention techniques are put into practice for the maximum preservation of tooth structure and function in modern dentistry. While treating deep dentine caries according to the traditional method defined by G.V. Black, removing all of the carious tissue can give way to perforation of the pulp, endodontic treatment or at some issues the extraction of the tooth. To protect the vitality of the pulp which is so important for the lifetime, function and prognose of a tooth, new methods and materials has been improved according to the increased understanding of the histology and phsyology of the dentin-pulp complex and the current developments of the adhesive resine systems and restorative materials. The selective caries removal techniques, disinfection of the cavity, the pulp capping methods and the currrent treatment methods used in the presence of a deep dentin caries were discussed in this review. Key words : Deep Dentine Caries, Disinfection, Selective Approaches, Stepwise-excavation

The aim of this study was to investigate the effect of hydrogen peroxide (HP) and carbamide peroxide (CP) on the surface roughness of five different composite resins using profilometer and scanning electron microscope (SEM). Thirty-six specimens (1 mm thick, 10 mm in diameter) of five composite resins were fabricated. Each composite group was equally divided into three subgroups as control, CP and HP. In control group, specimens were stored in daily refreshed distilled water during the 14-day testing period. In other groups, 10% HP (Opalescence Treswhite) and 10% CP (Opalescence PF) were applied and surface roughness values (Ra) of each specimen were measured with a profilometer at the end of 14 days. Additionally, SEM analysis was performed to evaluate the surface deformations of composite resins. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Ra values of composite groups exposed to bleaching agents were statistically higher than control group (p 0.05). There was no significant difference between Ra values after HP and CP application within each composite group while SEM micrographs showed higher surface alterations at HP group compared to CP. Among the composite resins tested, Ceram-X Mono revealed the lowest Ra values after CP and HP applications as seen at SEM images. Home bleaching agents increased the surface roughness of all composites. Except CP applied Ceram-X mono specimens, Ra values of all composite resins evaluated in this study exceeded the critical limit of 0.2 μm. Ceram-X mono was the least affected composite material after bleaching application. SCANNING 38:277-283, 2016. © 2016 Wiley Periodicals, Inc.

Dentin hypersensitivity has been defined as the short, sharp and severe pain arising from exposed dentin in response to thermal, evaporative, tactile, electrical, chemical or osmotic stimuli. Various theories about pain mechanism of dentin hypersensitivity have been reported but none of the pain mechanisms has not been proved yet. The epidemiological research reported hypersensitivity and day after day it is increasing. The aetiology of dentin hypersensitivity is multifactorial. Diagnosis is difficult. Different materials and methods have been used for the treatment of dentin hypersensitivity but a gold standart for treatment has not been found yet. The definition, theories about pain mechanisms, aetiology and risk factors, diagnosis and treatment of dentin hypersensitivity will be discussed in this review, Dentin aşırı hassasiyeti, açığa çıkmış dentinin termal, buharlaşma, dokunma, elektriksel, kimyasal veya osmotik uyaranlara karşı cevap olarak oluşturduğu kısa süreli, keskin ve şiddetli ağrı olarak tanımlanmaktadır. Ağrı mekanizması ile ilgili çeşitli teoriler ortaya atılmış ancak; dentin aşırı hassasiyetinin oluşturduğu ağrı mekanizması halen kesin olarak anlaşılamamıştır. Epidemiyolojik çalışmalar da çok farklı sonuçlar elde edilmiştir. Etyolojisi multifaktöri- yeldir. Görülme sıklığı gün geçtikçe artan dentin aşırı hassasiyeti diğer tüm patolojilerin elenmesi ile teşhis edilebildiği için teşhisi zor bir durumdur. Tedavisi amacıyla pek çok materyal ve yöntem denenmiştir ancak henüz altın standart olabilecek bir yöntem belirlenememiştir. Bu derlemede dentin aşırı hassas- iyetinin tanımı, ağrı mekanizması ile ilgili teoriler, etiyoloji ve risk faktörleri, tanı ve teşhisi ile tedavide kullanılan materyal ve yöntemler tartışılacaktır.

This study measured the elution of TEGDMA and BisGMA monomers from hybrid, micro-filled resin composites over 72 hours at different time intervals after polymerization with standard quartz-tungsten-halogen (QTH), high-intensity fast-curing QTH and standard blue light emitting diode (LED) light units. Samples were polymerized from the top and bottom surfaces, then immersed in methanol. High performance liquid chromatography (HPLC) was used to measure the amount of monomers released from the samples at various time intervals, ranging from 0 to 72 hours (0, 3, 6, 9, 12, 24, 48 and 72 hours). Data was analyzed using two-way ANOVA and Duncan tests with a significance level of 0.05. No significant differences were observed among curing groups in the elution of TEGDMA monomers at 0, 9, 12, 24, 48 and 72 hours; whereas, significant differences were observed among curing groups at 3 and 6 hours. BisGMA elution in samples immersed for longer periods (9-72 hours) were significantly higher than samples immersed for shorter time periods (0-6 hours); however, 72 hours appeared to be too short a period for the total elution of BisGMA into methanol.

Bu calismanin amaci dort farkli kondanse edilebilir kompozitin 20 sn ve 40 sn isik uygulamasi sonucu olusan alt ve ust yuzey sertlik degisiklerinin incelenmesidir. Yuzey sertlik olcumleri icin dort farkli kondanse edilebilir kompozit (P60, Surefil, Solitare 2 ve Pyramid-Dentin) 2 mm kalinliginda ve 8 mm capinda pleksi glass kalip icerindeki bosluklara yerlestirildi (n=20). Polimerizasyonlar halojen bir isik kaynagi kullanarak (600 mW/cm2) 20 sn (n=40) ve 40 sn (n=40) olacak sekilde polimerize edilen ornekler, Knoop Hardness (KHN) testi ile yuzey sertlik degerleri olculdu. Istatistiksel degerlendirme tek yonlu varyans analizi (ANOVA) ile yapildi ve gruplar arasi farkliklar Tukey testi ile belirlendi.En yuksek ust ve alt yuzey sertligi sirasi ile P60> Surefil> Solitare 2 = Pyramid-Dentin olarak tespit edildi. Isik uygulama suresi (20 sn veya 40 sn) Surefil kompozit disinda kompozitlerin bircogunda ust yuzey sertlik degerlerini degistirmedi. Sadece Surefil kompozit grubunda 40 snpolimerize edilen ornekler, 20 sn polimerizasyon gore daha fazla sertlik degeri gosterdi.

The aim of this study was to investigate the effect of home bleaching agents on the color and translucency of resin composites.Thirty disc shaped specimens (1mm thick) were fabricated from each resin composite (Reflexions, Grandio, Gradia Direct, Clearfil Majesty Esthetic, Ceram-X Mono) and divided into 3 subgroups as carbamide peroxide (CP, Opalescence 10% PF), hydrogen peroxide (HP, 10% Opalescence Treswhite Supreme) and control group (n=10). Baseline CIE L*a*b* color coordinates were measured with spectrophotometer and translucency parameters (TP) were calculated. CP and HP groups were treated with bleaching agents according to manufacturers' instructions and control group was stored in distilled water (DW) for 14 days. Color and translucency measurements were repeated and color differences were calculated, ΔE values3.3 were considered as clinically unacceptable.Clinically unacceptable color change was detected for all resin composites exposed to bleaching agents and there was significant color difference between the control group and bleached specimens (P0.05). However no significant color difference was found between CP and HP groups. Intragroup comparison revealed that Ceram-X Mono showed the highest color change but there was no significant difference among the other tested materials for both CP and HP groups. Intergroup comparison of TP values of CP, HP and control groups at the end of 14th day revealed that there was no statistical significant translucency difference among the groups.Application of CP and HP resulted in clinically unacceptable color change for all resin composites. Translucencies of the resin composites were not affected by bleaching procedure.The results of this in vitro study suggest that patients should be informed regarding a potential color change of existing resin composite restorations with the use of home bleaching agents.

The objective of the present investigation was to determine whether injurious thermal changes occur in the pulp chamber if a twist drill is used 10 times, and to find whether there is a correlation between temperature rise and distance between a drilled channel and the pulp chamber. Twenty caries-free, human, premolar teeth were randomly distributed to two dentists. With a new 2 mm twist drill, each dentist prepared 10 pinholes (one hole per tooth). Intrapulpal temperature change during the drilling procedure was recorded. The data were statistically analyzed by the Spearman rank order correlation coefficient. The results showed that twist drills should not be used for more than five pinholes (p less than 0.001). The distance between the pin channel and the pulp chamber does not influence heat generation in the pulp chamber.

To evaluate in vitro the curing effect of a very high intensity light-emitting diode (LED) unit and a conventional LED unit (including "soft-start" modes) on the microleakage of a pit and fissure sealant.120 intact caries-free human molars were randomly divided into six groups (n=20), sealed with Fissurit-F and polymerized using either a conventional halogen unit (Optilux) (Control group) in standard mode (40 seconds @ 600 mW/cm2); a very high intensity LED unit (Mini LED) in fast (10 seconds @ 1,100 mW/cm2) or soft-start mode (pulse mode: ten 1-second flashes @ 1,100 mW/cm2; exponential mode: exponential increase from 0 to 1,100 mW/cm2 within 10 seconds followed by 10 seconds @1,100 mW/cm2); or a conventional LED unit (Elipar Freelight) in standard (40 seconds @ 400 mW/cm2) or exponential mode (exponential increase from 0 to 400mW/cm2 within 12 seconds followed by 28 seconds @ 400 mW/cm2). Restored specimens were stored in distilled water at 37 degrees C for 24 hours. Specimens were then immersed in a 0.5% fuchsin dye solution for 24 hours, with half of the specimens from each group subjected to thermocycling (5/55 degrees C; x 1000) prior to dye immersion. After removal from the dye solution, specimens were sectioned and the degree of dye penetration scored. Data was statistically analyzed using the Kruskal-Wallis H test and the Mann-Whitney U-test (P0.05).There was no statistically significant difference in microleakage of pit and fissure sealant polymerized using various curing techniques. Thermocycling regimens had no effect on either LED- or halogen-cured specimens.

To evaluate the effect of thermocycling on microleakage of cervical cavities restored with hybrid and flowable resin composites polymerized with 3 different light-emitting diode (LED) curing techniques.A total of 120 wedge-shaped cervical cavities were prepared on the buccal surfaces of human molars, restored with hybrid resin composite (Z250, 3M Espe) or with flowable resin composite (Filtek Flow, 3M Espe), and cured with either an LED standard light, an LED high-intensity light, or an LED exponential mode, which is a kind of soft-start curing method. The teeth in each group were divided randomly into 2 subgroups: (1) thermocycling for 1,000 cycles at 5 degrees C and 55 degrees C with a dwell time of 60 seconds, and (2) no thermocycling treatment. All teeth were immersed in 0.5% basic fuchsin dye solution for 24 hours. The teeth then were longitudinally sectioned and scored on a 0 to 3 scale at the enamel and dentin margins.Nonparametric statistical analysis of the results showed a significant difference in microleakage between the nonthermocycled and thermocycled specimens, except for specimens cured with soft-start polymerization.The soft-start polymerization technique with LED light was not affected by thermocycling regimens.

INTRODUCTION: Urinary incontinence impacts the lives of older individuals and it is considered one of the most important and recurrent geriatric syndromes. The aim of this study is to determine the prevalence of urinary incontinence in cancer patients and to evaluate its association with age and quality of life. METHODS: One hundred and thirty three patients with cancer were assessed at hematology/oncology outpatient clinic. The validated form of the Turkish version of the International Consultation on Incontinence Questionnaire-Short Form was used to evaluate urinary incontinence and quality of life (QOL). Descriptive statistics were used. The association between urinary incontinence and age, gender, cancer type and quality of life were evaluated with chi square. RESULTS: A total of 133 patients including 84 male and 49 female were evaluated. The mean age of patients was 62.5±12.3. While 45.9% of patients are older than 65, 54.1% of them are less than 64. The rate of urinary incontinence was found 40.6% (n=54). The association between urinary incontinence and age, quality of life has been shown statistically significant with chi square (P DISCUSSION AND CONCLUSION: Our results suggest that urinary incontinence is a significant problem which is underdiagnosed and undertreated in cancer patients. It inversely affects the quality of life. While focusing on cancer and chemotherapy, this important problem should not be underestimated. This leaves incontinent patients with unresolved physical, functional, and psychological morbidity, and diminished quality of life. The study suggests that awareness and education regarding incontinence should be increased among cancer patients and screening of Urinary Incontinence is an important part of their assessment.

Despite the different light sources and polymerization techniques developed to eliminate it, microleakage of resin composite still remains a problem. This in vitro study was designed to compare the effects of exponential mode soft-start polymerization with those of standard and high-intensity continuous light polymerization on microleakage in Class II resin composite restorations.Standardized Class II cavities (4 mm wide, 4 mm long, 5 to 6 mm high, 2 mm deep) were prepared in 50 extracted human molars. Specimens were divided into 5 groups (n = 10) and restored using the same hybrid resin composite (Z250), but separately polymerized by one of five different methods: group 1: continuous halogen light polymerization for 40 s; group 2: continuous high-intensity halogen light polymerization for 10 s; group 3: exponential mode soft-start halogen light polymerization for a total of 40 s; group 4: continuous LED light polymerization for 40 s; Group 5: exponential mode soft-start LED light polymerization for a total of 40 s. All specimens were thermocycled for 1000 cycles at 5 degrees C to 55 degrees C and then placed in 0.5% basic fuchsin dye for 24 h. Specimens were then rinsed, embedded in resin and sectioned longitudinally. Dye penetration at occlusal and cervical margins was rated using a scale of 0 to 4. Data was analyzed using Kruskal-Wallis and Mann-Whitney U-tests.Significantly lower marginal leakage was recorded with exponential mode soft-start polymerization when compared to continuous light polymerization. No significant differences in microleakage were observed between LED and halogen light polymerization.Within the limits of this in vitro study, the use of the soft-start exponential mode of LED and/or halogen light units in the polymerization of hybrid composite was found to produce significantly lower microleakage at both occlusal and cervical margins when compared to continuous light polymerization methods.

Palatal cusps of nonvital maxillary premolar teeth were restored with a coronal-radicular restoration of posterior composite resin (Occlusin), amalgam (Tytin), or cermet (Chelon-Silver). Mean fracture strength values were: 370 lb for intact premolar teeth, 266 lb for amalgam, 215 lb for posterior composite resin, and 132 lb for cermet. From this in vitro study it can be suggested that for selected endodontically treated maxillary premolar teeth, the dentist can use acid-etch-retained posterior composite resin or pin-retained high copper amalgam material for a definitive coronal-radicular restoration. The use of cermet for this purpose is contraindicated.