The effect of seed layer cycles on the structural, optical, and morphological properties of ZnO nanorods.

In this study, ZnO seed layers with different cycles were formed on glass substrates by the sol-gel technique, and ZnO nanorods were grown on them by the hydrothermal method. Morphology and the structural characterization of the seed films and the ZnO nanorods are carried out by field emission scanning electron microscopy (FE-SEM) and x-ray diffraction techniques. In addition, to investigate the effect of seed layer deposition cycles on the optical properties of the ZnO nanorod arrays, UV/visible spectrophotometer and photoluminescence (PL) measurements were performed. The changes in structural and optical parameters such as dislocation density, strain, crystallite size, and optical band gap values on each seed layer deposition cycle were examined. The highest optical band gap and crystallite size were obtained for ZnO nanorods with 4 cycles seed layer as 3.22 eV and 63.6 nm, respectively. Also, in the PL spectrum, the largest ratio of UV-emission region to weak-visible emission region was obtained in ZnO nanorods having 4 cycles. In addition, the glucose detection properties of ZnO nanorods having 4 cycles were investigated using the PL measurements and it was found that UV-emission peak intensity of ZnO nanorods decreased as the glucose concentration increased from 8 to 40 mM. The results show that the number of deposition cycles of the seed layer has a strong influence on the orientation, crystal quality, and optical band gap of the growing ZnO nanorods, as well as significantly affecting their morphological properties. RESEARCH HIGHLIGHTS: High quality ZnO nanorods were grown on glass substrates by hydrothermal method. The effect of ZnO seed layer cycles on the structural, optical, and morphological characteristics of ZnO nanorods grown on were examined. It was found that the number of cycles of the seed layer is a critical parameter for growing quality and well-aligned ZnO nanorods.

Cement Thickness of Inlay Restorations Made of Lithium Disilicate, Polymer-Infiltrated Ceramic and Nano-Ceramic CAD/CAM Materials Evaluated Using 3D X-Ray Micro-Computed Tomography.

PURPOSE: To evaluate the marginal and internal cement thicknesses of inlay restorations made of various CAD/CAM materials using 3D X-ray micro-computed tomography (micro-CT) technique. MATERIALS AND METHODS: Caries-free extracted mandibular molars (N = 30) with similar size were randomly assigned to three groups (N = 10 per group). Mesio-occlusal-distal (MOD) cavities were prepared, and inlay restorations were obtained by milling out CAD/CAM materials namely, (a) IPS: monolithic lithium disilicate (control), (b) VE: polymer-infiltrated ceramic, and (c) CS: nano-ceramic using a CAM unit. Marginal and internal cement thicknesses were measured using 3D micro-CT. Data were analyzed using 1-way ANOVA and Tukey's tests (alpha = 0.05). RESULTS: The mean marginal and internal cement thickness were not significant in all inlay materials (p > 0.05). Mean marginal cement thickness (µm) was the lowest for the IPS group (67.54 ± 10.16) followed by VE (84.09 ± 3.94) and CS (95.18 ± 10.58) (p > 0.05). The internal cement thickness (µm) was the lowest in the CS group (54.85 ± 6.94) followed by IPS (60.58 ± 9.22) and VE (77.53 ± 12.13) (p > 0.05). CONCLUSION: Marginal and internal cement thicknesses of MOD inlays made of monolithic lithium disilicate, polymer-infiltrated ceramic, and nano-ceramic CAD/CAM materials were similar and all less than 100 µm, which could be considered clinically acceptable. CLINICAL SIGNIFICANCE: MOD inlays made of different CAD/CAM materials presented similar cement thickness, less than 100 µm.

A Cross-Sectional Survey on Reasons for Initial Placement and Replacement of Single Crowns.

This cross-sectional survey investigated the reasons for placement and replacement of single crowns, the type of materials selected for initial placement and evaluated their longevity. Information was collected over 19 months period using a questionnaire focusing on the principal reasons for the placement and replacement of crowns, selected material type and the age of the crowns at the time of replacement. A total of 842 single crowns were evaluated in 476 patients. Of the 842 crowns, 472 (56%) were initial placements and 370 (44%) replacements. The main reason for placement of first single crowns was related to endodontic problems (26.5%). Metal-ceramic was indicated significantly more frequent (88.9%; p⟨0.01) than other materials for the placement and replacement of single crowns. The median age of the replaced crowns was 6 years.

One-year clinical evaluation of different types of bulk-fill composites.

AIM: In the present study, we evaluated the 1-year clinical performance of a conventional posterior composite resin and three bulk-fill composite resins. METHODS: Fifty patients with four class II restorations under occlusion were enrolled in the present study. A total of 200 restorations were placed in the cavity, 50 for each material (Clearfil Photo Posterior, Filtek Bulk-Fill Flowable and Filtek P60, Tetric EvoCeram Bulk-Fill, and SonicFill). One operator placed the restorations in the cavity, and 1 week later the patients were called for baseline examination. Two calibrated examiners evaluated the restorations once every 3 months for 1 year, according to United States Public Health Service criteria. The data were analyzed using SPSS. Non-parametric tests (Kruskal-Wallis, Mann-Whitney U-test, and Friedman) were used for the analysis at a confidence level of 95%. RESULTS: The 1-year recall rate was 86%. All restorations showed minor modifications after 1 year. However, no statistically-significant differences were detected between the materials' performance at baseline and after 1 year for all criteria (P > 0.05). CONCLUSIONS: The bulk-fill composite resin materials showed similar clinical performance when compared with a conventional posterior composite resin. Further evaluations are necessary for the long-term clinical performance of these materials.

Analysis of Endodontic Complications Following Fixed Prosthodontic Rehabilitation.

PURPOSE: The aim of this study was to determine endodontic treatment needs and types of endodontic disease following fixed prosthodontic treatment 24 hours after tooth preparation, 1 week after tooth preparation, 1 month after placement, and 6 months after placement. MATERIALS AND METHODS: Study groups consisted of patients who attended a university dental hospital department of prosthodontics for fixed prosthodontic treatment from January 2011 to December 2013. All teeth were clinically and radiographically evaluated according to American Association of Endodontists evaluation criteria before preparation. Metal-ceramic fixed partial dentures were placed for all patients. A total of 1,633 abutment teeth were prepared with 1,100 pontics in 524 patients (214 female and 310 male). Participant age, sex, and tooth number were recorded. Endodontic treatment follow-up was scheduled for 24 hours after tooth preparation, 1 week after preparation, 1 month after placement, and 6 months after placement, and all teeth were evaluated after placement of FPDs according to a modified criteria. RESULTS: 2,733 retainers were placed with 624 FPDs. Of the FPDs, 332 (53%) were placed in the posterior and 196 (31.5%) in the anterior region. The remaining 96 FPDs (15.5%) were placed anteroposterior. The abutment/pontic ratio was 1.44:1. The number of retainers per FPD was 4.37. Of 1,633 abutment teeth, 103 were endodontically treated after placement of FPDs. Most observed endodontic disease was symptomatic irreversible pulpitis. There were statistically significant differences in terms of teeth regions (P < .001). When follow-up times of 24 hours, 1 week, 1 month, and 6 months were evaluated, there was no statistically significant difference among all teeth groups (P > .05). CONCLUSION: A total of 2,733 retainers on 624 FPDs were evaluated over 6 months, and the mean endodontic treatment need ratio was 6.3%.

The effect of different adhesives and setting times on bond strength between Biodentine and composite.

BACKGROUND: The aim of this study was to evaluate the effects of 3 different adhesives with different functional monomers, on the shear bond strength (SBS) of Biodentine®. METHODS: Acrylic blocks (n = 90) were prepared and a 2-mm height x 4-mm diameter hole was opened in each block. Every hole was completely restored with Biodentine®. Before preparation of composite restorations over the Biodentine® (2-mm height x 2-mm diameter), 3 different adhesives (Etch-37 (37%) w/BAC by Bisco & Prime Bond N&T, Clearfil S3 Bond and Adper Prompt L-Pop) were applied. SBS was evaluated using a universal testing machine, and failure mode for each sample was recorded. The results were statistically analyzed using 2-way ANOVA and post hoc Tukey test. RESULTS: When the megapascal values of all groups were compared, although there was no statistically significant difference in the different setting times (p>0.05), statistically significant differences were observed among all adhesive groups (p<0.05). Moreover, the highest SBS values were observed in the Clearfil S3 Bond group. CONCLUSIONS: Clinical performance of Biodentine® may be affected by adhesive procedures and its setting time.

Evaluation of school-based prevention program in Turkey: Results of a 24-month study.

OBJECTIVE: In this paper, cavity experiences of children with different levels of eruption and cavity activities that are enrolled at an elementary school with semi-rural characteristics in Kirikkale Provincial center were monitored for 2 years after a variety of protective applications. MATERIALS AND METHODS: Three hundred and twenty-two children at the age of 7-11 were included in this study. Children were grouped as follows according to their cavity experiences and applications done: Group 1 - control group (with or without cavities) - was given hygiene training only; Group 2 - with medium level cavity activity (2-4 cavities in average) - oral hygiene training + surface restoration applied; Group 3 - children with 2-4 cavities on average - oral hygiene training + professional flour gel applied; Group 4 - children with 2-4 cavities in average - oral hygiene training + flour gel applied with brush; Group 5 - children with extreme cavity activity (children with 5 or more cavities) - oral hygiene training + surface restoration + professional flour gel combination applied. RESULTS: At the end of the 2(nd) year, 277 children were reached. The increase of number of cavities in permanent teeth was determined as 35%, 0%, 1%, 0%, and 7% in groups 1-5, respectively. The difference between groups was found to be significant (Chi-square analysis, Pearson Chi-square = 27.002, P < 0.01). CONCLUSION: These findings have showed that, in Kirikkale Provincial center, some cavity-preventive measures such as surface restoration and gel applications, along with hygiene training, could provide optimum protection for school-age children.

Shear bond strength of bulk-fill and nano-restorative materials to dentin.

OBJECTIVES: Bulk-fill composite materials are being developed for preparation depths of up to 4 mm in an effort to simplify and improve the placement of direct composite posterior restorations. The aim of our study was to compare shear-bond strength of bulk-fill and conventional posterior composite resins. MATERIALS AND METHODS: In this study, 60 caries free extracted human molars were used and sectioned parallel to occlusal surface to expose midcoronal dentin. The specimens were randomly divided into four groups. Total-etch dentine bonding system (Adper Scotchbond 1XT, 3M ESPE) was applied to dentin surface in all the groups to reduce variability in results. Then, dentine surfaces covered by following materials. Group I: SonicFill Bulk-Fill, Group II: Tetric EvoCeram (TBF), Group III: Herculite XRV Ultra, and Group IV: TBF Bulk-Fill, 2 mm × 3 mm cylindrical restorations were prepared by using application apparatus. Shear bond testing was measured by using a universal testing machine. Kruskal-Wallis and Mann-Whitney U-tests were performed to evaluate the data. RESULTS: The highest value was observed in Group III (14.42 ± 4.34) and the lowest value was observed in Group IV (11.16 ± 2.76) and there is a statistically significant difference between these groups (P = 0.046). However, there is no statistically significant difference between the values of other groups. In this study, Group III was showed higher strength values. CONCLUSION: There is a need for future studies about long-term bond strength and clinical success of these adhesive and bulk-fill systems.

A Survey on Prevalence, Causes and Prevention of Postcementation Hypersensitivity.

This study evaluated the prevalence and causes of post-cementation sensitivity and possible prevention measures according to the experience of dentists through an internet survey. A questionnaire was prepared with 25 items based on a survey introduced by Rosenstiel and Rashid. An online site was created for the participation to the survey. A total of 322 participants responded the questionnaire. The results of the questionnaire indicated the amount of tooth preparation (42.1%) is the most frequent reason for hypersensitivity followed by water-cooling with pressure (11.2%) and provisionals (10.9%). "Very important" response for tooth reduction, time before cementation, overheating, luting agent, occlusion and provisionals were found to be of statistical significance (p⟨0.001). Comparing respondents' opinions the incidence of post-cementation sensitivity appears to be underestimated. Tooth reduction, preparation under high volume spray and quality of provisional restorations was considered to have a significant impact on the incidence of post-cementation sensitivity according to the dentists surveyed across Turkey. Respondents to the questionnaire considered the use of antimicrobial, desensitizing, resin bonding, hemostatic agents, varnishes, type of liner material, rotary instruments to be less effective for prevention of post-cementation sensitivity.

Evaluation of the clinical success of class I cavities prepared by an Er:YAG laser-5-year follow-up study.

The purpose of this study was to evaluate, after 5 years, the clinical success of preparing class 1 composite resin restorations with an Er:YAG laser. Sixty-five teeth of 30 patients were included in the study, and an Er:YAG laser emitting at a wavelength of 2.94 µm was used for the class I cavity preparations with not more than one third of the mesiodistal width of the occlusal surfaces of each tooth. All cavities were restored with a light-cured composite resin, following a single bond application. After the baseline examination, restorations were reevaluated by the same experienced clinician after 5 years, using the modified Ryge criteria. At the end of 5 years, 41 of the 65 restorations were evaluated in 22 patients and scored. With respect to marginal discoloration, anatomic form, color match, and surface texture, significant differences were found between baselines tested after 5 years. Clinical evaluation of postoperative sensitivity showed that 90.2 % were rated as alpha. All restorations evaluated in this study demonstrated acceptable clinical performance within the evaluation period based on the alpha and bravo ratings for clinically satisfactory restorations. Further evaluations are necessary for a better clinical performance analysis.

Evaluation of Novel Microabrasion Paste as a Dental Bleaching Material and Effects on Enamel Surface.

PURPOSE: Dental fluorosis is an enamel dysplasia that can cause serious aesthetic and psychological problems. An examination of the literature shows that the microabrasion method is the most effective way to treat fluorosis. This study aimed to produce a prototype microabrasion paste for the treatment of fluorosis stains and to examine the effects of the paste on tooth structure and color in vitro. MATERIAL AND METHODS: Forty extracted upper incisor teeth were used in this study. The teeth were divided into four treatment groups: a prototype microabrasion paste group (N = 10), an Opalustre paste group (N = 10), a 37% phosphoric acid gel group (N = 10), and a distilled water (control) group (N = 10). Following treatment, all specimens in each of the four groups were examined by scanning electron microscopy for changes in their surface enamel. Changes in tooth color changes of the 1st and 2nd groups were measured before and after treatment by a VITA Easyshade Advance spectrophotometer. RESULTS: In scanning electron microscopy evaluations, significant differences were not observed between the 1st and 2nd groups. Differences in three color-measuring coordinates between the 1st and 2nd were also not statistically significant (p > 0.05). CONCLUSIONS: The study demonstrated that the prototype paste is a viable treatment option for dental fluorosis. CLINICAL SIGNIFICANCE: The findings in this study demonstrated that the tested prototype microabrasion paste is extremely harmless, minimally invasive agent, and able to improve the color, shine and chrome values of the teeth.

Talon cusps occurring concurrently with dens invaginatus on a permanent maxillary lateral incisor: a case report and literature review.

A talon cusp is a prominent accessory horn-like structure that projects from the cingulum or cementoenamel junction of the maxillary or mandibular teeth. It can occur in primary and permanent dentition and can lead to occlusal interference, irritation of the tongue, pulpal necrosis, caries, and periodontal problems. Talon cusp has been reported to affect both sexes, and may be unilateral or bilateral. Talon cusps occur most often on the palatal surface of permanent maxillary incisors. A comprehensive literature review revealed only 6 reported cases of facial talon cusps. A talon cusp occurring simultaneously with dens invaginatus in a tooth is extremely rare; to date, only 9 case reports have been published. This article presents a unique case of concurrent dens invaginatus and palatal and facial talon cusps in the right maxillary central incisor of a 12-year-old girl.

Prevalence of caries among preschool-aged children in a central Anatolian population.

OBJECTIVE: Early childhood caries (ECC) is a particularly destructive form of tooth decay that afflicts young children. The etiology and associated factors of ECC should be studied adequately to overcome this health hazard. The aim of this study was to determine caries prevalence and its consequences in toddlers in an Anatolian city, Kirikkale. MATERIALS AND METHODS: Examinations were performed in family medicine centers by three calibrated dentists during a period of 6 months. The status of dental caries was recorded according to the World Health Organization (WHO) criteria. We recorded the clinical indexes of decayed, missed, and filled teeth (DMFT and dmft; upper-case letters refer to permanent and lower-case letters to primary teeth), and decayed, missed, and filled surfaces (DMFS). RESULTS: Totally 3171 toddlers were included (52% males and 48% females). The mean age was 25.8 ± 10.1 months. The prevalence of ECC in preschool children was 17.3%, while the mean df(t) was 0.63 ± 1.79. ECC increased significantly with age. Dental caries were mostly observed in primary maxillary central teeth. Occlusal and buccal surfaces were the most affected sites. The difference in distribution of caries between maxilla and mandibula was found to be statistically significant (P < 0.05). CONCLUSIONS: When compared to other data obtained from various epidemiologic studies, the toddlers living in Kirikkale city center had a significant caries level. This observation had clearly suggested that early preventive measures should urgently be put into effect all over the city.

One-year clinical evaluation of Quixfil and Gradia Direct composite restorative materials in posterior teeth.

OBJECTIVE: The purpose of this study was to evaluate and compare the 12 month clinical performances of two different posterior composites in Class I and Class II restorations. METHODS: Class I and class II cavities of 62 patients, 74 Quixfil (Dentsply/ Xeno V) and 68 Gradia Direct (GC America/G bond) composite restorations were placed by two dentists. Only small and medium-sized cavities were included in the study. Independent evaluations were performed at baseline (one week), after three months, six months, and one year, by one trained examiner using the modified U.S. Public Health Service rating criteria. Color match, marginal integrity, anatomical form, surface roughness, marginal or interfacial staining, postoperative sensitivity, and secondary caries were evaluated. RESULTS: Both restorative materials showed only minor changes, and no differences were detected between their performance at baseline and after 12 months. Postoperative sensitivity was observed in only one Quixfil restoration. In regard to the clinical performance, there was no statistically significant difference between the materials used. CONCLUSIONS: Both materials showed good clinical results with dominant alpha scores at the end of 12 months.

Taurodontism in a central anatolian population.

The aim of this retrospective study was to evaluate the frequency of the occurrence of taurodontism in a Turkish population with using panoromic radiographs. A retrospective study was performed using full-mouth periapical and panoramic radiographs of 6912 patients (3860 females and 3052 males) ranging in age from 15 to 50. A total of 97362 posterior (including third molars) were evaluated. A chi-square test was used to determine the difference in the prevalence of tauorodntism between genders. Eighteen patients were found to have a taurodont molar (10 women and 8 men [P = 0.98]). The overall incidence of patients with taurodont molars was 0.26 % and the prevalence of taurodont molars from all teeth examined was 0.024%, and the prevalence taurodonts were significantly more common in the mandibula compared with the maxilla (71.0% cf 29.0% respectively, P < 0.05). It was almost equally distributed between males and females. Taurodontism is not uncommon in Turkish population but further larger scale studies are required to assess its prevalence in the general population to compare it with other ethnic groups.

Halitosis: From diagnosis to management.

Halitosis is formed by volatile molecules which are caused because of pathological or nonpathological reasons and it originates from an oral or a non-oral source. It is very common in general population and nearly more than 50% of the general population have halitosis. Although halitosis has multifactorial origins, the source of 90% cases is oral cavity such as poor oral hygiene, periodontal disease, tongue coat, food impaction, unclean dentures, faulty restorations, oral carcinomas, and throat infections. Halitosis affects a person's daily life negatively, most of people who complain about halitosis refer to the clinic for treatment but in some of the people who can suffer from halitosis, there is no measurable halitosis. There are several methods to determine halitosis. Halitosis can be treated if its etiology can be detected rightly. The most important issue for treatment of halitosis is detection etiology or determination its source by detailed clinical examination. Management may include simple measures such as scaling and root planning, instructions for oral hygiene, tongue cleaning, and mouth rinsing. The aim of this review was to describe the etiological factors, prevalence data, diagnosis, and the therapeutic mechanical and chemical approaches related to halitosis.

Early childhood caries update: A review of causes, diagnoses, and treatments.

Dental caries (decay) is an international public health challenge, especially amongst young children. Early childhood caries (ECC) is a serious public health problem in both developing and industrialized countries. ECC can begin early in life, progresses rapidly in those who are at high risk, and often goes untreated. Its consequences can affect the immediate and long-term quality of life of the child's family and can have significant social and economic consequences beyond the immediate family as well. ECC can be a particularly virulent form of caries, beginning soon after dental eruption, developing on smooth surfaces, progressing rapidly, and having a lasting detrimental impact on the dentition. Children experiencing caries as infants or toddlers have a much greater probability of subsequent caries in both the primary and permanent dentitions. The relationship between breastfeeding and ECC is likely to be complex and confounded by many biological variables, such as mutans streptococci, enamel hypoplasia, intake of sugars, as well as social variables, such as parental education and socioeconomic status, which may affect oral health. Unlike other infectious diseases, tooth decay is not self-limiting. Decayed teeth require professional treatment to remove infection and restore tooth function. In this review, we give detailed information about ECC, from its diagnosis to management.

Human immunodeficiency virus/acquired immunodeficiency syndrome knowledge among high school students in Kirikkale province of Turkey.

BACKGROUND: The purpose of the present study was to assess the existing level of knowledge of high school children about human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) and the sources of their information. MATERIALS AND METHODS: A cross-sectional survey was conducted in two high schools in Kirikkale, Turkey and data were collected by a self-administered questionnaire. Multi-stage sampling technique was used to obtain a representative sample. RESULTS: Four hundred and seventy three participants; 230 males and 243 females were analyzed. Their ages ranged from 15 to 19 years with a mean age of 16.81 ± 1.27. 92.2% of the students claimed to have heard about HIV/AIDS prior to the study with slightly more females than males. Although with some misconceptions, majority of the participants knew that HIV is not transmitted by sharing meals, casual contact, and sleeping in the same room and using the same bathroom. 93.4% identified HIV/AIDS as a life-threatening disease and 27% believe that there is a cure for AIDS. 64% and 22.8% respectively believed that the people can protect themselves by using condoms and by avoiding sexual contact. Internet was preponderantly claimed as the most important source of information about HIV/AIDS. CONCLUSION: Empirical evidence from this study suggests that the students have a fairly high knowledge of HIV/AIDS. This is not without some misconceptions about the prognosis of the disease. Internet was the major source of HIV/AIDS information.

Unilateral fusion of mandibular permanent lateral incisor with canine: A report of a rare case.

Fusion is a developmental anomaly which occurs due to a union of one or more adjacent teeth during morpho-differentiation of the dental germs. Early diagnosis of this condition is important because it may cause clinical problems, such as esthetic concerns and arch asymmetry. These anomalies may be unilateral or bilateral and may affect either dentition, although the deciduous teeth are more commonly affected. This report describes a rare case of unilateral fusion between the mandibular permanent lateral incisors and the canine. Only few cases have been previously reported in the English literature. Hence this article aimed at reporting a case of this rare condition and evaluating the presence of any associated pathology.

Rural dentistry: Is it an imagination or obligation in community dental health education?

During the past two decades, epidemiologic studies in less developed or developing countries have clearly reported that caries prevalence shows the distinctive patterns over the word, even though it is declining in many developed countries. Due to huge rural districts where arrival is problematic and ineffective dental and preventive care centers in most suburban districts, there has been significant difference between the different parts of the communities to provide dental care service, and unfortunately the sole preventive measure has been limited with the advising of using the tooth brush and paste. The problems are usually arisen not only from the inadequacy of trained personnel but also from the absence of an effective economic and pragmatic system which aims to effectively dispense the dental service to all over the country. For this reason, the basic aim of dental care should be to carry out the many dental services in a multidisciplinary manner within the first appointment and to serve the people at their own homes and/or districts. Clearly, the needed multidisciplinary dental care system can lead to a new educational doctrine for rural dental practice. This versatile and practical training program based on specific perceived needs of a specific population(s) could need a new educational program. So, various preventive and/or restorative procedures included by this new doctrine could be named as "rural dentistry." In this review, with the examples from the many in vivo studies carried out under rural conditions over the world, the probable practices in this specific dental doctrine have generally been exemplified.