Oguzhan Gorler

The Effects of Er:YAG, Nd:YAG, and Ho:YAG Laser Surface Treatments to Acrylic Resin Denture Bases on the Tensile Bond Strength of Silicone-Based Resilient Liners.

OBJECTIVE The present study was to assess the effect of surface treatments of Er:YAG, Nd:YAG, and Ho:YAG lasers on the tensile bond strength of a silicone-based resilient liner to an acrylic denture in an in vitro setting. METHODS Experimental dumbbell-shaped specimens (75 mm) were produced by combining two acrylate pieces fabricated from heat-polymerized acrylic resin (36 mm) with 3 mm of Molloplast(®)-B filling between them. The specimens (n=200) were randomly divided in half for thermocycling, and each 100 specimen set was randomized into five groups (n=20) with different surface treatments: control (no surface treatment), sandblasting, Er:YAG laser, Nd:YAG laser, and Ho:YAG laser. A tensile bond strength test was performed. The effect of the laser surface treatments was examined with scanning electron microscopy. RESULTS Only the Er:YAG laser increased the tensile bond strength compared with the other treatments. The other laser groups showed lower bond strengths. The Ho:YAG laser resulted in considerably reduced tensile bond strength. The scanning electron microscopy images showed that applying laser surface treatments modified the surface of the denture base resin. CONCLUSIONS There was not an overall improvement with the use of the studied laser modalities in the adhesion quality of resilient denture liner to acrylic resin, although Er:YAG laser showed a potential to improve their adhesion. These laser modalities need to be subjected to further studies to determine optimal setup for use in prosthodontics.

Shear Bond Strength of Composite and Ceromer Superstructures to Direct Laser Sintered and Ni-Cr-Based Infrastructures Treated with KTP, Nd:YAG, and Er:YAG Lasers: An Experimental Study

OBJECTIVE The aim of this study was to examine the shear bond strength (SBS) of ceromer and nanohybrid composite to direct laser sintered (DLS) Cr-Co and Ni-Cr-based metal infrastructures treated with erbium-doped yttrium aluminum garnet (Er:YAG), neodymium-doped yttrium aluminum garnet (Nd:YAG), and potassium titanyl phosphate (KTP) laser modalities in in vitro settings. METHODS Experimental specimens had four sets (n = 32) including two DLS infrastructures with ceromer and nanohybrid composite superstructures and two Ni-Cr-based infrastructures with ceromer and nanohybrid composite superstructures. Of each infrastructure set, the specimens randomized into four treatment modalities (n = 8): no treatment (controls) and Er:YAG, Nd:YAG, and KTP lasers. The infrastructures were prepared in the final dimensions of 7 × 3 mm. Ceromer and nanohybrid composite was applied to the infrastructures after their surface treatments according to randomization. The SBS of specimens was measured to test the efficacy of surface treatments. Representative scanning electron microscopy (SEM) images after laser treatments were obtained. RESULTS Overall, in current experimental settings, Nd:YAG, KTP, and Er:YAG lasers, in order of efficacy, are effective to improve the bonding of ceromer and nanohybrid composite to the DLS and Ni-Cr-based infrastructures (p < 0.05). Nd:YAG laser is more effective in the DLS/ceromer infrastructures (p < 0.05). KTP laser, as second more effective preparation, is more effective in the DLS/ceromer infrastructures (p < 0.05). SEM findings presented moderate accordance with these findings. CONCLUSIONS The results of this study supported the bonding of ceromer and nanohybrid composite superstructures to the DLS and Ni-Cr-based infrastructures suggesting that laser modalities, in order of success, Nd:YAG, KTP, and Er:YAG, are effective to increase bonding of these structures.

The Effects of Some Drinks on Saliva pH

Objectives: The purpose of this study is to evaluate the effects of some drinks on saliva pH. Methods: Systemic and periodontally healthy individuals aged 18-23 years were included in the study. Individuals saliva pHs were measured three hours after breakfast. Three groups were set up to measure after 1 minute, 10 minutes and 30 minutes after drinks were drunk and the effects of Turkish coffee, cola, ayran and green tea on saliva pH were investigated. Results: The most pronounced pH changes occurred in the first group. The lowest pH values were reached when cola was consumed while the highest pH values were reached when green tea was consumed. Within the pH measurement time period, the drink group with the least tendency of pH value change was green tea. Conclusion: In order to prevent tooth decay, there is a need to raise awareness about conscious and controlled consumption of beverages that may lead to significant reductions in salivary pH.

M.Ö. 2 yüzyıl-M.S. 12 yüzyıl arasındaki döneme ait insan kafatası kemiklerindeki interorbital, biorbital ve bizigomatic mesafelerin üç boyutlu çok kesitli bilgisayarlı tomografi ile değerlendirilmesi

Ulkemiz sinirlari icerisinde Zeytinli Ada gibi cok sayida arkeolojik buluntu yeri vardir. Bu gibi kazi yerlerinde insan iskeletine ait kemiklerde bulunabilmektedir. Bulunan insan iskeletlerinin antropolojik degerlendirmeleri ozellikle kafatasi dikkate alinarak yapildiginda yas ve cinsiyet acisindan onemli bilgiler vermektedir. Ozellikle radyolojik incelemelerin kullanilmasi bu bilgilerin guvenilirligini artirmaktadir. Calismamiz 2007-2011 yillari arasinda gerceklestirilen Zeytinli Ada da gerceklestirilen kazilar sonucunda ortaya cikarilan, M.O. 2 yuzyil ve M.S. 12 yuzyillari arasi 6 kadin, 16 erkek, 22 bireye ait kafatasi alinarak gerceklestirilmistir. Cok kesitli bilgisayarli tomografi ile alinan goruntuler is istasyonu yazilimi ile uc boyutlu hale donusturlerek interorbital, biorbital ve bizigomatik olcumleri yapildi Kafatasi olcum degerleri ortanca (aralik) olarak whisker grafik ile sunuldu. Ortanca kadin ve erkek degerlerin karsilastirilmasi Mann-Whitney testi ile yapildi. Olcum degerlerinin arasindaki korelasyonlari incelenmesi Pearson korelasyon testi ile yapildi. P degerinin 0,05 degerinin altinda olmasi anlamli olarak kaydedildi. Veriler degerlendirildiginde erkek ve kadin interorbital ve bizigomatik mesafeleri arasindaki fark anlamli bulunmadi. Biorbital mesafeleri dikkate alindiginda ise erkek kafataslarinin biorbital mesafeleri kadinlarinkine gore anlamli olarak daha fazla bulundu. Interorbital ile biorbital ve bizigomatik mesafelerinin korelasyonu analizlerine bakildiginda dikkate deger bir iliskiye bulunmadi. Calismamizda erkeklerin kafataslarinda kadinlara gore bizigomatik mesafelerinin uzun olmasi, kafatasinin lateral cikintilarin daha belirgin oldugunu gostermektedir. Bu da cinsiyet ayriminda onemli bir kriter olarak karsimiza cikmaktadir.

Porselen ile titanyumun bağlanma dayanımına Nd-YAG lazerin etkinliğinin incelenmesi

Objectives:To investigate bond strengthbetween Estenia, is a kind of seromer has beenincreasingly used in dentistry, low fusing porcelainand titanium metal sub-structures after differentsurface treatments.Materials and Methods: In the present study,ISO9693:1999 standards 25x3x0.5mmdimensionsof the samples used prepared with titanium in themetal substructure. Metal sample surface blasting(n=12) and Nd-YAG laser with a blasting + laser(n=12) by application of the working groups wereformed. Low-temperature materials as porcelainsuperstructure estenia seromer group size 8x3x3mmmetal substructure to be appliedaccording to the instructions of the manufacturer.Later examples, universal testing device todetermine the three-point transverse fractureresistance test was performed. Unit load applicationrate of 0.5 mm/min and the distance between thejaws adjusted to 20 mm. Example of porcelainmetal sub-structure, divided into groups, the type ofthe current connection N/mmstrength values wererecorded. Mann-Whitney U test was used for theevaluation of the data obtained.Results: Titanium metal sub-structures in termsof strength of connection estenia materialdetermined to be sufficient, can be a seriousalternative to high temperature porcelains weredetected. However, the Nd: YAG laser irradiationof titanium surface connection valueswere determined in a value increase, but statistically notsignificant.Conclusion:Blasting and sandblasting +samples compared to laser therapy, sand blasting +laser groups showed no statistically significantdifferences in terms of connection strength.(p>0.05).