What is Known About Caries in Relation to Restorations as a Reason for Replacement? a Review

1995 ◽  
Vol 9 (4) ◽  
pp. 394-402 ◽  
Author(s):  
L. Ozer ◽  
A. Thylstrup

In the past 20 years, a great many studies have identified secondary caries to be the most common reason for the replacement of restorations. This review raises the question whether clinicians use 'secondary caries' as a catch-all into which they put a variety of reasons for replacement, or whether they do have professionally based reasons for focusing on caries adjacent to restorations. There is no consensus among researchers concerning the nature of secondary caries, but it is possible to identify two major-and conflicting-trends : One adheres to a critical approach concerning the frequency of replacements and recommends a much more conservative evaluation of existing fillings. In contrast, the other trend focuses on the clinical undetectable microleakage as the major risk factor for the initiation and uncontrolled dentinal spread of secondary caries. Since the latter trend offers a reasonable explanation for the clinicians' concern about invisible 'secondary caries', and hence reinforces the tendency to replacement, it is relevant to reconsider the conventional concept that microleakage leads to the initiation of secondary caries. Available data indicate that visible gaps and marginal discrepancies are poorly related to secondary caries, and that secondary caries is a localized phenomenon caused by localized conditions for the evolution of cariogenic plaque. Consequently, secondary caries is not a universal attack along the entire interface between tooth and restoration, but rather a new lesion or a re-beginning of caries on the surface due to local conditions for plaque formation with cariogenic potential. It is concluded that reinforcement of a new and more appropriate professional behavior should be based on diffusion of existing knowledge of dental caries as a disease rather than on simplified criteria for the placement and replacement of dental restorations.

2014 ◽  
Author(s):  
Γεώργιος Γούλας

Η διατριβή ερευνά τις πολύπλευρες όψεις της ιστορίας στο καλλιμαχικό έργο, εξετάζοντας αφενός την ποιητική απεικόνιση της σύγχρονης πολιτικο-στρατιωτικής ιστορίας των ελληνιστικών βασιλείων και αφετέρου την ποιητική αξιοποίηση των ιστοριογραφικών κειμένων (γενεαλογίες, μυθογραφίες, εθνογραφίες, παραδοξογραφίες, τοπικές ιστορίες). Όλα αυτά τα ιστορικά ερεθίσματα ενεργοποιούν τα λόγια ανακλαστικά του ποιητή και αφήνουν ίχνη στα ποιήματα. Τα κύρια ερωτήματα που επιχειρείται να απαντηθούν είναι τα εξής δύο. Πρώτον, ο Καλλίμαχος είναι ένας αυλικός ποιητής που εξυμνεί τα «ιστορικά» κατορθώματα των Πτολεμαίων; Δεύτερον, ο λόγιος ποιητής βρίσκει στις ιστοριογραφικές πηγές ένα καινούργιο άλλοθι εγκυρότητας, αν όχι την αλήθεια, το οποίο παλαιότερα ο αρχαϊκός ποιητής αντλούσε από τις Μούσες; Η διατριβή εισάγει ως κύριο θεωρητικό εργαλείο ανάλυσης των προηγούμενων ερωτημάτων την έννοια της μεταϊστορίας, η οποία υποδιαιρείται σε μεθοδική και κριτική. Αφενός ο Καλλίμαχος στοχάζεται πάνω στην ιστορική μεθοδολογία, που θα πρέπει να τηρήσει για την έρευνα του παρελθόντος. Αφετέρου ο ίδιος υιοθετεί μία πιο κριτική προσέγγιση, όταν θα πρέπει ως αυλικός ποιητής να υμνήσει τους νικηφόρους πολέμους των Πτολεμαίων ή όταν θα πρέπει ως λόγιος ποιητής να ακολουθήσει τις συμβάσεις των ιστοριογραφικών έργων και να αποδεχθεί ως απόλυτες αυθεντίες τις ιστοριογραφικές αφηγήσεις. Αυτή η κριτική δεν παίρνει ποτέ τη μορφή της ευθείας σύγκρουσης και ρήξης αλλά γίνεται με συγκαλυμμένο και αμφίσημο τρόπο, ο οποίος περιγράφεται με τον όρο διττή αναγνωσιμότητα. Προτείνεται, λοιπόν, να ειδωθεί η χρήση της ιστορίας από τον Καλλίμαχο όχι αποκλειστικά ως επίδειξη γνώσεων ή ως μηχανή τεκμηρίωσης αλλά ως ένα πεδίο, όπου επαναπροσδιορίζεται ο ρόλος της ποίησης και κατοχυρώνεται η αυτονομία και η «σοφία» της ποιητικής τέχνης έναντι των άλλων πηγών και ειδών γνώσης. Δεν πρέπει να διαφεύγει της προσοχής ότι σκοπός του ποιητή είναι να γράψει ποίηση και όχι ιστορία, αντλώντας έμπνευση αλλά και κρατώντας αποστάσεις από τη χαώδη φύση των βιβλιακών πηγών. Η λόγια ποίηση αναγνωρίζει εγκαίρως την αντινομία και τους περιορισμούς που κρύβει η διάσωση και εξήγηση του παρελθόντος μέσα από τις καταγεγραμμένες πηγές. Μία τέτοια αντισυμβατική στάση από την πλευρά του λογίου ποιητή ασφαλώς δεν θα μπορούσε να τη φανταστεί η επίσημη πολιτιστική πατρωνεία των Πτολεμαίων. Για τους βασιλείς η πνευματική ακτινοβολία του Μουσείου και η μεγαλεπήβολη συγκέντρωση βιβλίων και γνώσεων στην αλεξανδρινή Βιβλιοθήκη ισοδυναμούσε με θεμελίωση πολιτικής δύναμης. Αυτές οι βλέψεις της εξουσίας, όμως, δεν ενδιέφεραν κατ’ ανάγκην την ποίηση, η οποία είχε τα δικά της οράματα. SUMMARYThe thesis explores the multifaceted aspects of the history in Callimachus’ work, considering, on the one hand, its poetic depiction of contemporary political - military history of the Hellenistic kingdoms and, on the other hand, the poetic use of historiographical texts (genealogies, mythographies, ethnographies, paradoxographies, local histories). All these historical stimuli activate the literary reflexes of the poet and leave traces on the poems. There are two main questions which the thesis attempts to answer. The first is whether Callimachus is a courtier poet who celebrates the "historic" achievements of the Ptolemies and the second, does the scholar poet find a new validity alibi, if not the truth, in the historiographical sources which primarily the archaic poet drew from the muses? The thesis introduces as the main theoretical tool for analysis of the previous questions the sense of meta – history which is subdivided into methodical and critical. On the one hand, Callimachus reflects on the historical methodology, which should be respected for the research of the past. On the other hand, he adopts a more critical approach, in cases when, as a courtier poet, he has to praise the victorious wars of Ptolemy or when, as a scholar poet, he has to follow the conventions of historiographical works and accept the historiographical narratives as absolute authorities. This criticism never takes the form of direct conflict and rupture but it is conducted in a disguised and ambiguous manner, which is described by the term dual readability. It is proposed, therefore, that the use of history by Callimachus has to be seen not exclusively as a demonstration of knowledge or a mechanism of documentation but as a field, in which the role of poetry is redefined and the autonomy and "wisdom" of the poetic art against other sources and kinds of knowledge is guaranteed. It should also be considered that the purpose of the poet is to write poetry and not history, drawing inspiration but also keeping his distance from the chaotic nature of bookish sources. The literary poetry recognizes the contradiction and the limitations which the preservation and interpretation of the past through


2018 ◽  
Vol 6 (10) ◽  
pp. 1888-1894 ◽  
Author(s):  
Megha Gupta

BACKGROUND: Dental caries has continued to be the major oral disease in the past, as well as the present scenario. Cariogenic sugars in the presence of specific bacteria Streptococcus mutans over a period have been attributed as the major etiologic agent for dental caries. The association between sugar consumption and dental caries has been well documented. AIM: Hence, the dental profession shares an interest in the search for safe, palatable sugar substitutes. METHODS: Therefore, the use of a suitable sugar substitute can help in combating dental caries. RESULTS: Out of the various sugar substitutes available, xylitol is the most widely used. It is available in various forms. It decreases the plaque formation, bacterial adherence and inhibits the growth of Mutans Streptococci. CONCLUSION: This article provides a comprehensive review of the sugar substitutes, present-day availability, role in the prevention of dental caries and their safety concerns.


Author(s):  
K. T. Tokuyasu

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).


Author(s):  
Prakash Rao

Image shifts in out-of-focus dark field images have been used in the past to determine, for example, epitaxial relationships in thin films. A recent extension of the use of dark field image shifts has been to out-of-focus images in conjunction with stereoviewing to produce an artificial stereo image effect. The technique, called through-focus dark field electron microscopy or 2-1/2D microscopy, basically involves obtaining two beam-tilted dark field images such that one is slightly over-focus and the other slightly under-focus, followed by examination of the two images through a conventional stereoviewer. The elevation differences so produced are usually unrelated to object positions in the thin foil and no specimen tilting is required.In order to produce this artificial stereo effect for the purpose of phase separation and identification, it is first necessary to select a region of the diffraction pattern containing more than just one discrete spot, with the objective aperture.


2010 ◽  
Vol 51 (1-2) ◽  
pp. 215-224
Author(s):  
Alexander Carpenter

This paper explores Arnold Schoenberg’s curious ambivalence towards Haydn. Schoenberg recognized Haydn as an important figure in the German serious music tradition, but never closely examined or clearly articulated Haydn’s influence and import on his own musical style and ethos, as he did with many other major composers. This paper argues that Schoenberg failed to explicitly recognize Haydn as a major influence because he saw Haydn as he saw himself, namely as a somewhat ungainly, paradoxical figure, with one foot in the past and one in the future. In his voluminous writings on music, Haydn is mentioned by Schoenberg far less frequently than Bach, Mozart, or Beethoven, and his music appears rarely as examples in Schoenberg’s theoretical texts. When Schoenberg does talk about Haydn’s music, he invokes — with tacit negativity — its accessibility, counterpoising it with more recondite music, such as Beethoven’s, or his own. On the other hand, Schoenberg also praises Haydn for his complex, irregular phrasing and harmonic exploration. Haydn thus appears in Schoenberg’s writings as a figure invested with ambivalence: a key member of the First Viennese triumvirate, but at the same time he is curiously phantasmal, and is accorded a peripheral place in Schoenberg’s version of the canon and his own musical genealogy.


2018 ◽  
Vol 47 (2) ◽  
Author(s):  
Kempe Ronald Hope

Countries with positive per capita real growth are characterised by positive national savings—including government savings, increases in government investment, and strong increases in private savings and investment. On the other hand, countries with negative per capita real growth tend to be characterised by declines in savings and investment. During the past several decades, Kenya’s emerging economy has undergone many changes and economic performance has been epitomised by periods of stability, decline, or unevenness. This article discusses and analyses the record of economic performance and public finance in Kenya during the period 1960‒2010, as well as policies and other factors that have influenced that record in this emerging economy. 


2020 ◽  
Vol 9 (1) ◽  
pp. 190-197
Author(s):  
Luh Putu Desy Puspaningrat ◽  
Gusti Putu Candra ◽  
Putu Dian Prima Kusuma Dewi ◽  
I Made Sundayana ◽  
Indrie Lutfiana

Substitution is still a threat to the failure of ARV therapy so that no matter how small it must be noted and monitored in ARV therapy. The aims  was analysis risk factor substitution ARV first line in therapy ARV. This study was an analytic longitudinal study with retrospective secondary data analysis in a cohort of patients receiving ARV therapy at the District General Hospital of Buleleng District for the period of 2006-2015 and secondary data from medical records of PLHA patients receiving ART.  Result in this study that the percentage of first-line ARV substitution events is 9.88% (119/1204) who received ARV therapy for the past 11 years. Risk factors that increase the risk of substitution in ARV therapy patients are zidovudine (aOR 4.29 CI 1.31 -2.65 p 0.01), nevirapine (aOR1.86 CI 2.15 - 8.59 p 0.01) and functional working status (aOR 1.46 CI 1.13 - 1.98 p 0.01). 


1999 ◽  
Vol 150 (12) ◽  
pp. 484-488 ◽  
Author(s):  
Wolf Hockenjos

Concepts of near-natural forestry are in great demand these days. Most German forest administrations and private forest enterprises attach great importance to being as «near-natural» as possible. This should allow them to make the most of biological rationalisation. The concept of near-natural forestry is widely accepted, especially by conservationists. However, it is much too early to analyse how successful near-natural forestry has been to date, and therefore to decide whether an era of genuine near-natural forest management has really begun. Despite wide-spread recognition, near-natural forestry is jeopardised by mechanised timber harvesting, and particularly by the large-timber harvester. The risk is that machines, which are currently just one element of the timber harvest will gain in importance and gradually become the decisive element. The forest would then be forced to meet the needs of machinery, not the other way round. Forests would consequently become so inhospitable that they would bear no resemblance to the sylvan image conjured up by potential visitors. This could mean taking a huge step backwards: from a near-natural forest to a forest dominated by machinery. The model of multipurpose forest management would become less viable, and the forest would become divided into areas for production, and separate areas for recreation and ecology. The consequences of technical intervention need to be carefully considered, if near-natural forestry is not to become a thing of the past.


Author(s):  
Daiva Milinkevičiūtė

The Age of Enlightenment is defined as the period when the universal ideas of progress, deism, humanism, naturalism and others were materialized and became a golden age for freemasons. It is wrong to assume that old and conservative Christian ideas were rejected. Conversely, freemasons put them into new general shapes and expressed them with the help of symbols in their daily routine. Symbols of freemasons had close ties with the past and gave them, on the one hand, a visible instrument, such as rituals and ideas to sense the transcendental, and on the other, intense gnostic aspirations. Freemasons put in a great amount of effort to improve themselves and to create their identity with the help of myths and symbols. It traces its origins to the biblical builders of King Solomon’s Temple, the posterity of the Templar Knights, and associations of the medieval craft guilds, which were also symbolical and became their link not only to each other but also to the secular world. In this work we analysed codified masonic symbols used in their rituals. The subject of our research is the universal Masonic idea and its aspects through the symbols in the daily life of the freemasons in Vilnius. Thanks to freemasons’ signets, we could find continuity, reception, and transformation of universal masonic ideas in the Lithuanian freemasonry and national characteristics of lodges. Taking everything into account, our article shows how the universal idea of freemasonry spread among Lithuanian freemasonry, and which forms and meanings it incorporated in its symbols. The objective of this research is to find a universal Masonic idea throughout their visual and oral symbols and see its impact on the daily life of the masons in Vilnius. Keywords: Freemasonry, Bible, lodge, symbols, rituals, freemasons’ signets.


2017 ◽  
Vol 68 (2) ◽  
pp. 323-327
Author(s):  
Cristian Levente Giuroiu ◽  
Maria Vataman ◽  
Gabriel Melian ◽  
Dragos Bularda ◽  
Ludmila Lozneanu ◽  
...  

The study aimed to assess the number, localization and distribution of interleukin 6 (IL-6) positive cells in healthy pulp, acute and chronic pulpitis. The study group included 48 patients aged between 18-72, treated in University of Medicine and Pharmacy Grigore T. Popa Iasi, Romania. The pulpectomy was performed on 42 patients diagnosed with acute and chronic pulpitis. The other 6 patients, without signs of dental caries or periodontal disease, were submitted to extractions of teeth for orthodontic purposes, with pulpectomy performed before extraction. The pulp samples were examined with optic microscope. The detection and assessment of IL-6 were performed using immunohistochemical technique. Data were statistically analysed using non-parametric tests. According to morphopathological criteria, 42.85% were classified as acute pulpitis and 57.14% as chronic pulpitis. The pulp samples in control group were not associated with IL-6 positive cells. The analysis of all samples with acute and chronic pulpitis identified 73.80% samples with IL-6 and 26.20% associated with the absence of IL-6. The highest frequency of IL-6 positive cells was recorded in rich-cell zone of crown dental pulp. The systemic distribution of IL-6 positive cells was mostly diffused without well-defined orientation. IL-6 release in acute and chronic pulpitis is significantly higher comparing with healthy pulp tissue.


Sign in / Sign up

Export Citation Format

Share Document