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Purpose: To assess the degree of conversion (DC) at different levels of a resin-based luting agent used with different commercial posts. Methods: A resin-based luting agent (Variolink II) was light-cured in a simulated dowel space in combination with different fiber posts: GC Fiber Post (GC), DT Light Safety Lock (SL), RelyX Fiber Post (RX), Reforpost (RE), DT Light Post Illusion (LPI), FRC Postec Plus (FP), Radix (RA), Snowpost (SP), Dentin Post X (DP), Macro lock Illusion (MI), and Composipost (CP). After 24 hours, DC was assessed through micro-Raman analysis at the coronal, middle, and apical thirds. Two-way ANOVA and Tukey test were used for post-hoc comparisons (P< 0.05). Results: The results demonstrated that the post-type, dowel space level, and between-factor interaction were statistically significant (P< 0.001). Differences in DC were observed at different depths for RX, RE, LPI, SL, DP, MI and CP, decreasing from the coronal to the apical third. Although the resin-based luting agent should be able to polymerize in absence of light, a higher DC was found following light irradiation (with a decreasing effect from the coronal to the apical third). (Am J Dent 2012;25:17-20).

Purpose: The purpose of this study was to evaluate whether gaseous ozone application affects the immediate enamel bond strength or microleakage of 2 dental sealants. Methods: Sixty bovine incisors were randomly divided into 4 groups, and sealants were applied to the enamel surfaces as follows: ozone + Concise; Concise (control); ozone + UltraSeal XT Plus; and UltraSeal XT Plus (control). Ozone application was performed for 80 seconds, and shear bond strength was measured. Additionally, 60 human molars were randomly divided into 4 groups, as aforementioned, and sealants were applied onto occlusal surfaces. Dye penetration (microleakage) was assessed. Results: No significant differences were found between the 2 sealants. Ozone application did not result in a significant reduction in enamel bond strength or an increase in microleakage. Conclusions: Ozone gas did not compromise the adhesion of tested materials; therefore, one can disinfect the enamel surface before placing a dental sealant without impairing the material's clinical performance. (Pediatr Dent 2012;34:284-8) Received September 16, 2010 vertical bar Lost Revision February 26, 2011 vertical bar Accepted March 6, 2011

Objectives The aim of this study was to investigate, by the means of microtensile bond strength (μTBS) test, gelatin and in situ zymography, the influence of 0.2% CHX contained within a commercially available adhesive on long-term bond strength and endogenous enzymatic activity. Methods Non-carious teeth were subjected to μTBS test (N = 15 for each group) and stressed until failure. μTBS was evaluated immediately and after 12-month storage in artificial saliva at 37 °C. Dentin powder was obtained from additional teeth (N = 7) for gelatin zymography, while for in situ zymography, 3 teeth for each group were selected. Gelatin and in situ zymography were performed in dentin powder and slices of dentin, respectively, to assess the ability of 0.2% CHX blended within the adhesive to inhibit endogenous enzymatic activity. Results μTBS bond strength was higher in the CHX-containing groups, immediately as well as after aging. The bond strength significantly decreased after 12-month aging. The activation of endogenous MMPs was found to be related to the presence of CHX within the adhesive system and the bonding strategy employed. Conclusions Under this perspective 0.2% CHX blended within Peak Universal adhesive monomer seems to increase immediate bond strength, to preserve bond strength over time and to efficiently inhibit endogenous enzymatic activity in dentin. Hence, blending the CHX in low concentrations within the adhesive could be recommended as a feasible technique in every-day clinical practice. Clinical significance Using CHX-containing adhesives could be recommended due to several benefits: it seems to increase the longevity of the hybrid layer; the inhibitor appears to be efficiently delivered to the dentinal substrate and to inhibit endogenous enzymatic activity, without prolonging chair time.

Periodontitis is a common inflammatory disease characterized by a complex etiology, which is the result of a combination of genetic and environmental factors. Genetic variants linked to the periodontitis disease were already investigated, however, little was known regarding the severity of this disease. Recently, long runs of homozygosity (ROH) were associated with several multifactorial diseases. Therefore, in our work, we tried to assess the role of ROH and periodontitis status. We found an association between the excess of homozygosity owing to ROH and staging of periodontitis. More in detail, the total amount of homozygosity owing to ROH is positively associated with an increased severity of periodontitis (P = 0.0001). Regression tree analysis showed the impact of ROH burden in discriminating individuals with mild periodontitis stages I and II and periodontitis stages III and IV (P 1). Among them, we found a total of 33 genes. Interestingly, some of these genes were previously associated with granulocyte or platelet measures, both linked to the onset and the progression of periodontal disease. Our results suggest the not only single variants association test could help to risk assessment but even individual genomic features; furthermore, our ROH mapping highlighted the possible role of multiple genes in periodontal development.

Background Monosomy 1p36 is the most common terminal deletion syndrome with an autosomal dominant pattern of inheritance. This syndrome is defined by an extremely wide spectrum of characteristics; however, developmental delay and intellectual disability of various degree are present in all patients and about the 90% of patients have a severe intellectual disability. Dental agenesis or other dental anomalies have not been described in previous reports. Case presentation We report the case of two little sisters born from healthy and non-consanguineous parents, presenting with dental anomalies and one of them with epilepsy, dilated cardiomyopathy with left-ventricular non-compaction, strabismus, history of poor growth, hypotonia and mild language delay. Patients were evaluated in several departments (genetic, child neuropsychiatric, cardiology, odontostomatology, ophthalmology, otorhinolaryngology) of Institute for Maternal and Child Health, IRCCS Burlo Garofolo, Trieste, Italy. They underwent investigations such as electrocardiogram, echocardiogram, dental orthopantomography X-Ray and Computed Tomography, electroencephalograms, abdomen ultrasound, blood tests, IQ tests, genetic analysis. They both have an Intelligence Quotient greater than 70 and a negative neurologic exam. Each sister carries the same 1p36 deletion of about 2.3 Mb. Genetic analysis of the parents’ blood samples (Single Nucleotide Polymorphism- array, karyotype and Fluorescent In Situ Hybridization) did not reveal any deletion, translocation or inversion and confirmed the paternity. A third sib of the probands does not carry the 1p36 deletion or other quantitative alterations. Conclusion This report describes a new trait linked to monosomy 1p36, namely a mild intellectual outcome associated with significant dental anomalies. Our finding suggests that 1p36 deletion syndrome may present with a mild cognitive impairment or even with a normal intellectual development: this is very important for the genetic counselling, especially in a prenatal setting. Moreover, we report the third study with recurrent 1p36 deletion syndrome in two siblings, likely due to germline mosaicism. Finally, we believe that the dental anomalies should be investigated in 1p36 deletion syndrome and that the spectrum of the condition could be broader than we assume.

Studies have investigated the relationship between periodontitis and the decrement of the bone mineral density (BMD). However, there is limited knowledge on the possible association between BMD-related genes and susceptibility to periodontitis development. To fill this gap, a total of 157 genes, previously associated with BMD, were analyzed in 442 subjects affected by chronic periodontitis. Candidate gene analyses resulted in two RBMS3 deleterious variants, rs55872743 and rs7636555, significantly associated (p-value < 3.28 × 10−06) with periodontitis status. These results will shed new light on the possible role of genes linked to BMD affecting periodontitis.

Objectives Chronic periodontitis is a common pathological condition that affects the supporting tissue of the teeth, leading to progressive alveolar bone destruction and teeth loss. The disease is caused by bacteria and derives from an altered host immune and inflammatory response, also involving different factors such as the oral hygiene, smoking, genetic background etc. The innate immune response, the first line of host defense, could also play an important role in the susceptibility to chronic periodontitis. In this study, we evaluated the possible association between periodontal disease and seven genetic variations within DEFB1 and LTF genes, encoding for β-defensins 1 and lactoferrin (two members of oral innate immune system), in an Italian isolated population. Subjects and Methods DEFB1 5’UTR g.-52G>A (rs1799946), g.-44C>G (rs1800972), g.-20G>A (rs11362), 3’UTR c*5G>A (rs1047031), c*87A>G (rs1800971), LTF p.Ala29Thr (rs1126477) and p.Lys47Arg and (rs1126478) were analyzed in 155 healthy individuals and 439 chronic periodontitis patients from North East Italy. Results Significant associations were found between periodontitis and g.-20G>A (rs11362) and g.-44C>G (rs1800972) SNPs in DEFB1 gene as well as p.Ala29Thr (rs1126477) and p.Lys47Arg (rs1126478) SNPs in LTF gene. Discussion Our results suggest the involvement of DEFB1 and LTF genetic variations in the susceptibility towards development of periodontitis. This article is protected by copyright. All rights reserved.

Objectives: Stresses produced during the fabrication of copings and by chewing activity can induce a tetragonal-to-monoclinic (t&ndash, m) transformation of zirconia. As a consequence, in the m-phase, the material is not able to hinder possible cracks by the favorable mechanism known as &ldquo, transformation toughening&rdquo, This study aimed at evaluating if different marginal preparations of zirconia copings can cause a premature phase transformation immediately after manufacturing milling and after chewing simulation. Methods: Ninety copings using three commercial zirconia ceramics (Nobel Procera Zirconia, Nobel Biocare Management AG, Lava Classic, 3M ESPE, Lava Plus, 3M ESPE) were prepared with deep-chamfer, slight-chamfer, or feather-edge finish lines (n = 10). Specimens were tested in a chewing simulator (CS-4.4, SD Mechatronik) under cyclic occlusal loads simulating one year of clinical service. Raman spectra were acquired and analyzed for each specimen along the finish lines and at the top of each coping before and after chewing simulation, respectively. Results: Raman analysis did not show any t&ndash, m transformation both before and after chewing simulation, as the typical monoclinic bands at 181 cm&minus, 1 and 192 cm&minus, 1 were not detected in any of the tested specimens. Conclusions: After a one-year simulation of chewing activity, irrespective of preparation geometry, zirconia copings did not show any sign of t&ndash, m transformation, either in the load application areas or at the margins. Consequently, manufacturing milling even in thin thickness did not cause any structural modification of zirconia ceramics &ldquo, as received by manufacturers&rdquo, both before and after chewing simulation.

SUMMARY Purpose: Degree of conversion (DC) affects the physicochemical properties of dental adhesives. The aim of this study was to measure the DC within the hybrid layer of four one-step self-etch adhesives using Raman microspectroscopy. The hypothesis tested was that there was no difference among the tested adhesives. Methods and Materials: The selected one-step self-etch adhesives (Clearfil S3 Bond Plus, I-BOND, G-BOND, and Adper Easy Bond) were applied on human dentin disks and polymerized in accordance with the manufacturers' instructions. Specimens were transversally cut to expose the bonded interfaces to the micro-Raman beam, and Raman spectra were collected along the dentin/adhesive interface. Measurements were performed at 1-μm intervals. The relative intensities of bands associated with the C=C bond (at 1640 cm−1) and an internal stable peak (1610 cm−1) were determined to calculate the degree of conversion within the hybrid layer. Data were statistically analyzed with Kolmogorov-Smirnov and Bartlett tests and Kruskal-Wallis and Mann-Whitney U-tests. Results: The DC ranked as follows: G-BOND (93%±6%) ≥ Adper Easy Bond (92%±6%) ≥ I-BOND (89%±7%) > Clearfil S3 Bond Plus (80%±14%) (p Conclusions: Based on the results of this study, all of the tested self-etch adhesives showed a clinically acceptable DC that was material dependent.