INTRODUCTION: The molecular structure of the insoluble brown-colored substance is produced through the reaction of mixing the most common irrigation agents in endodontic treatments as sodium hypochlorite and chlorhexidine has not been fully described in the literature yet. The aim was to analyze the precipitate is formed through the reaction of mixing sodium hypochlorite and chlorhexidine by using Fourier-transform infrared (FT-IR) spectroscopy.

METHODS: FT-IR spectrum of the experimental precipitate was recorded. The vibrational FT-IR spectrum of the experimental precipitate was analyzed and compared with the spectrum of the chlorhexidine obtained from available databases in transmission mode (4000-400 cm-1).

RESULTS: Eight-shift was recorded at 3335, 2436, 2160, 2004, 1896, 1636, 579 and 555 cm-1 in the spectrum of the experimental precipitate. These shifts were compared with the vibrations of chlorhexidine.

DISCUSSION AND CONCLUSION: After interaction with sodium hypochlorite, chlorhexidine structure was broken and converted to a new insoluble product as 1,6-Hexandiylbis{imino[({[(4-chlorphenyl)ammonio](imino)methyl}amino)methylyliden]})diammonium.

INTRODUCTION: The purpose of this in-vitro study is to evaluate the effect of different digital impression systems on the impression accuracy of dental implant.
METHODS: In a standard full-arch maxillary model, the tooth 26 was removed and an implant analogue was placed. The scanning process was first performed with a reference scanner. Taking measurements with intra-oral scanners repeated 10 times for each group using 3 different digital scanners [Trios 3, iTero Element 2 and Medit i500]. Obtained images were output in STL format and compared using 3D inspection software. The mean deviation amounts were determined by overlapping the STL data obtained to determine the trueness and precision of the impressions. The data were statistically compared using Kruskal-Wallis test and Mann-Whitney U tests. Statistical significance was determined at p<0.05.
RESULTS: Significant differences were found among the trueness values of the groups obtained by different digital impression systems (p<0,05). The highest trueness was obtained in the Trios 3 (32.81 ±11.65μm) group followed by the groups iTero Element 2 (49.12 ±8.97μm) and Medit i500 (46.25 ±17.08μm). No significant difference was found among the different digital impression groups for the precision values (p>0,05).
DISCUSSION AND CONCLUSION: The impression accuracy of dental implants is affected by the different digital impression systems.

INTRODUCTION: The aim of this study was to evaluate the effect of the polymerization with different light sources and thermocycling on the color stability of three compomer resins.
METHODS: In this study, 3 different brand (1- Glasiosite Caps, Voco, 2- Dyract XP, Dentsply ve 3-Nova Compomer, Imıcrly) and 2 different color (A2 and A3) compomer resins were tested. From each materials, 10 specimens cured with a LED curing light 1 (Satelec mini LED, Acteon) and 10 specimens cured with a LED curing light 2 (Elipar S10, 3M-ESPE), totally 120 specimens were prepared in 10mm diamension and 2mm thick. Initial measurements were made with a spectrophotometer according to CIELAB system. Specimens were subjected to 5000 thermocycles. After the thermocycling procedure, colors of the specimens were re-measured and color changes (ΔE) were determined.
RESULTS: The initial color differences (ΔE=0.42±0.32-2.13±0.51) formed by light devices were statistically significant (p<0.05). After thermocycling, there were statistically differences between the ∆E values of the specimens polymerized with both light source 1 (∆E= 0.79±0.80-3.93±1.55) and light source 2 (∆E=3.01±1.43-5.13±1.80)(p<0.05).
DISCUSSION AND CONCLUSION: Light sources and thermocycling could affect the color stability of the compomer resins. The effect of light sources is clinically acceptable but the thermocycling may cause more color change than acceptable values.

INTRODUCTION: In this preliminary study, survival of vital teeth treated by direct and indirect pulp capping following the complete caries removal in deep dentin lesion was evaluated. The secondary objective was to observe the response of pulp dentin complex to different types of capping and restorative materials.
METHODS: 50 permanent teeth with deep dentin lesion were included to this study. After complete caries removal, different protocols were applied according to pulp exposure namely direct or indirect pulp capping. The teeth were treated with different combinations of pure calcium hydroxide, Dycal, zinc oxide eugenol, glass ionomer cement, composite resin, amalgam. Clinical and radiographical evaluations were performed at 6th month.
RESULTS: After complete caries removal, unintentional pulp exposure was observed in 54% of the teeth. Totaly 4 teeth from direct pulp-capping (n=3) and indirect pulp-capping (n=1) failed due to inflammation. All failed restorations belonged to Dycal+ composite resin groups.
DISCUSSION AND CONCLUSION: If pulp exposure occurred, possibility of failure would be higher compared to non-exposure group. Additionally, in the success of pulp-capping treatment, pure calcium hydroxide “Ca(OH)2 ” as pulp-capping material seems to be more reliable than factory product calcium hydroxide paste “Dycal”.

INTRODUCTION: The purpose of this study is to evaluate the effect of acidic agents on ion leaching of dental porcelain.
METHODS: Fifty discs were fabricated from 3 different types of porcelain. All porcelains were immersed in 5 liquid agents. Ion leaching was measured with an inductively coupled plasma – mass spectrometer. Surface characteristics of specimens were examined using environmental scanning electron microscopy.
RESULTS: Al ion leaching values of Vita VM 13, IPS Empress and e.max Ceram porcelain were significantly different in cherry juice and lemon juice groups (p = 0,012; p <0,001). In 4% acetic acid solution, citrate buffer solution and deionized water groups, there were no statistically significant differences in Al ion leaching values among porcelain groups (p = 0.672; p = 0.222; p = 0.097). Li and Y ion leaching values of Vita VM 13, IPS Empress and e.max Ceram porcelain were significantly different in cherry juice, lemon juice, 4% acetic acid and citrate buffer groups (p <0.001). In deionized water group, there were no statistically significant differences in Li and Y ion leaching values among porcelain groups (p = 0.092; p = 0.457).
DISCUSSION AND CONCLUSION: All porcelains included in the study are degraded in acidic substances or acidic foods and beverages.

Objectives: To evaluate and compare the facial soft tissue thickness values of patients with different types of malocclusion.
Methods: The study sample consisted of lateral cephalometric radiographs of 120 adolescent patients (60 men; mean age 14.4±1.2 years, 60 women; mean age 15.04±0.8 years) with normodivergent growth pattern, divided into three groups according to the sagittal malocclusions: Class I, Class II, and Class III. The reference line was identified according to definitions by Arnett and McLaughlin, and 16 linear measurements were analyzed by using Dolphin Imaging 11.5 Software Program. For statistical evaluation, one-way ANOVA and Bonferonni post hoc test were used.
Results: All facial soft tissue thickness measurements were found to be greater for men. Statistically significant differences among the groups were found in both women and men at the following measurements: lower lip length, lower lip to chin and mandibular incisor to chin. The lower lip length and mandibular incisor to chin was the greatest in Class III group.
Conclusion: Soft tissue thickness differences among skeletal malocclusions were observed at the lower lip length, lower lip to chin and mandibular incisor to chin measurements for both genders. The differences among skeletal malocclusions should be taken into consideration both during planning and the treatment period.

INTRODUCTION: The aim of this study was to evaluate the effect of hyaluronic acid and dentin graft on bone healing of criticalsized cortical osteoporotic bone defects.
METHODS: 24 adult female Wistar rats underwent bilateral ovariectomy. Six weeks later, when the animals were osteoporotic, the rats were divided into three groups: Group D (dentin grafted), Group D-HA (dentin grafted with hyaluronic acid) and Group C (control). A 5-mm diameter critical-size defect was created in the calvarium of each animal. In Group D; the defect was filled by dentin graft, in group D-HA; the defect was filled by dentin graft and hyaluronic acid, in group C; the control group was left empty. All animals were euthanized at 28th day. New bone formation at each defect site was evaluated both histologically and immunohistochemically according to hematoxylin and eosin, BMP2, TGFβ, and osteopontin levels.
RESULTS: Histologically, group D and group D-HA exhibited significantly more new bone formation than group C. Immunohistochemically; The TGFβ and osteopontin levels were significantly higher in Group D-HA. The BMP2 levels did not differ significantly between the groups D and group D-HA.
DISCUSSION AND CONCLUSION: Dentin graft combined with hyaluronic acid enhances bone regeneration in critical-size calvarial defects in osteoporotic rats.

INTRODUCTION: Purpose of this study was to evaluate the fracture resistance of occlusal veneer and overlay CAD/CAM restorations made of polymer-infiltrated ceramic and lithium disilicate ceramic.
METHODS: 60 non-carious mandibular first molar teeth were divided into 5 groups: Polymer-infiltrated ceramic (PIC)-overlay group (n: 12), PIC-occlusal veneer group (n: 12), Lithium disilicate ceramic (LDC)-overlay group (n: 12), LDC-occlusal veneer group (n: 12) and control group (n: 12) which was consisted of natural teeth. Standard overlay and occlusal veneer cavities were prepared. Restorations were manufactured using CEREC, cemented with adhesive resin cement. All specimens subjected to artificial aging process in mastication simulator, fracture resistance was assessed with universal testing machine. Fractured surfaces were examined with stereomicroscope.
RESULTS: Obtained data were evaluated with 1-way ANOVA, Tukey HSD and Student t tests. In terms of fracture force values, no statistically significant difference was found among groups (PIC Overlay: 2196,77±427,84; PIC Occlusal Veneer: 2326,19±469,07; LDC Overlay: 1960,16±438,85; LDC Occlusal Veneer: 2148,53±460,18) except control group (2942,3±724,60). In terms of failure modes, no statistically significant difference was found among groups; occlusal veneer restorations showed mostly Burke class I-II fractures.
DISCUSSION AND CONCLUSION: For restorative treatment of posterior worn teeth, minimal invasive occlusal veneer restorations made of LDC or PIC materials are successful alternatives.

INTRODUCTION: The aim of the study was to measure the lingual cortical bone thickness of the mandibular third molars, and to investigate its relationship with the tooth position.
METHODS: Cone beam computerized tomography images which contained a total of 649 impacted mandibular third molars were included in the study. The closest distance of the crown and root tip of each tooth to the lingual soft tissues was measured. The impacted teeth were grouped as mesioangular, distoangular, vertical, horizontal, and buccolingual impaction. The teeth were also grouped as type A, B, and C relation according to their distance to lingual soft tissues.
RESULTS: Of the total 649 teeth, 590 (90.9%) showed type A relation, 21 (3.2%) type B relation and 38 (5.9%) type C relation. Of these teeth, 302 were impacted in mesioangular, 141 in distoangular, 107 in horizontal, 86 in vertical, 13 in buccolingual position. No significant difference was found between the positions of the teeth and their distance to lingual soft tissues statistically.
DISCUSSION AND CONCLUSION: Three dimensional radiographic evaluation may provide for predicting the complications before surgical procedures in very rare occasions in which the lingual bone thickness of mandibular third molars is suspected to be very thin that cannot be answered by 2D imaging.

As a result of the research and development of devices and materials at atomic and molecular level due to nanotechnology, nanomaterials are increasingly used in dentistry and applications. Thus, nanodentistry, technology and dentistry has taken place as a branch of science. In the future, traditional dental practice is expected to change drastically with the potential impacts of nano development practices, such as the preservation and maintenance of general oral health, the rapid diagnosis and treatment or prevention of oral cancer and diseases. In this review, general and explanatory information about nanomaterials used in dentistry is given and the future prospects of nanotechnology are discussed.

In particular, magnetic resonance imaging is used in the imaging of soft tissues, examination of the temporomandibular joint disc, imaging of soft tissue associated pathologies in the head and neck region, and diagnosis of malignancies related with oral mucosa. Ultra high field magnetic resonance imaging techniques are currently used for research, and studies involving dentistry are also being carried out. The purpose of this study is; to present the use areas of magnetic resonance imaging in dentistry in the context of current studies and to examine the use potential areas of ultra high field magnetic resonance imaging in dentistry.

Mandibular condylar fracture is one of the commonest maxillofacial fractures. Untreated or improperly treated mandibular condylar fractures can cause serious consequences. The treatment of mandibular condylar fractures has always been a controversial issue because of the many important vital structures adjacent to the regional anatomy. Several different methods have been reported in the classification and treatment of these fractures.The main methods currently used in the treatment of mandibular condylar fractures are divided into two main groups as closed reduction and open reduction. Closed reductiont is the first choice in the treatment of condylar fractures for a long time. Open reduction is becoming more popular due to improvements in osteosynthesis materials. The most appropriate treatment method should be chosen considering the condition of the fragments, age of the patient and clinical symptoms. In this article, current and different treatment modalities reported in the classification and treatment of condylar fractures have been evaluated and reviewed.