scholarly journals An Intraoral OCT Probe to Enhanced Detection of Approximal Carious Lesions and Assessment of Restorations

2020 ◽  
Vol 9 (10) ◽  
pp. 3257
Author(s):  
Hartmut Schneider ◽  
Martin Ahrens ◽  
Michaela Strumpski ◽  
Claudia Rüger ◽  
Matthias Häfer ◽  
...  

Caries, the world’s most common chronic disease, remains a major cause of invasive restorative dental treatment. To take advantage of the diagnostic potential of optical coherence tomography (OCT) in contemporary dental prevention and treatment, an intraorally applicable spectral-domain OCT probe has been developed based on an OCT hand-held scanner equipped with a rigid 90°-optics endoscope. The probe was verified in vitro. In vivo, all tooth surfaces could be imaged with the OCT probe, except the vestibular surfaces of third molars and the proximal surface sections of molars within a "blind spot" at a distance greater than 2.5 mm from the tooth surface. Proximal surfaces of 64 posterior teeth of four volunteers were assessed by intraoral OCT, visual-tactile inspection, bitewing radiography and fiber-optic transillumination. The agreement in detecting healthy and carious surfaces varied greatly between OCT and established methods (18.2–94.7%), whereby the established methods could always be supplemented by OCT. Direct and indirect composite and ceramic restorations with inherent imperfections and failures of the tooth-restoration bond were imaged and qualitatively evaluated. The intraoral OCT probe proved to be a powerful technological approach for the non-invasive imaging of healthy and carious hard tooth tissues and gingiva as well as tooth-colored restorations.

1990 ◽  
Vol 270 (2) ◽  
pp. 297-304 ◽  
Author(s):  
G Madapallimattam ◽  
A Bennick

Human saliva contains a large number of phosphopeptides derived by cleavage of acidic proline-rich proteins (APRPs). These peptides were purified by column chromatography and they constituted 0.5% of APRPs in parotid saliva, but 11% of APRPs in saliva expectorated from the mouth (whole saliva), indicating that there is considerable cleavage of APRPs after secretion from the gland. Similarly to APRP, the phosphopeptides bind Ca2+, but they accounted for only 4% of protein-bound Ca2+ in whole saliva. APRPs as well as the phosphopeptides inhibited formation of hydroxyapatite, but, whereas 19-20 micrograms of APRP was needed for 50% inhibition, only 0.7-3.3 micrograms of purified peptides was needed for the same degree of activity, and the phosphopeptides accounted for 18% of total inhibitory activity in whole saliva. All phosphopeptides adsorbed on hydroxyapatite in vitro, and adsorption of phosphopeptides on tooth surfaces in vivo could also be demonstrated, indicating that they would be able to inhibit unwanted mineral formation on the tooth surface in vivo. Degradation of APRPs after secretion therefore does not lead to a loss of their biological activities.


2004 ◽  
Vol 841 ◽  
Author(s):  
Michelle E. Dickinson ◽  
Adrian B. Mann

ABSTRACTSalivary pellicle is an organic biofilm formed by the physisorption of proteins and carbohydrates onto the surface of dental enamel exposed to the oral environment. The pellicle has several key roles in oral physiology including lubrication and reduction of friction between teeth during mastication, as well as chemical protection of the enamel against acidic solutions. However, pellicle proteins are known to react with dietary compounds to cause extrinsic staining on the tooth surface.In this study, nanoindentation and AFM have been used in vitro to examine the acquired salivary pellicle formed in vivo on dental enamel. The mechanical properties, growth, structure and morphology of pellicle grown in vivo on human enamel surfaces have been analysed. In addition, the effects of dietary agents such as polyphenols on the pellicle's morphology and properties have been studied.It was found that initial adsorption of proteins on the enamel surface occurred within 30 seconds of exposure to the oral cavity, with full growth achieved within 2 hours. Differences in the properties of the pellicles such as surface adhesion, and time dependent effects due to polyphenol interaction were measured using nanoindentation. It was seen that the polyphenol interaction has a significant effect on these properties. These results suggest that the stained pellicle is mechanically stiffer, but also less viscous and more fluid like. This could explain why traditional tooth brushing techniques do not efficiently remove this layer.


2010 ◽  
Vol 192 (12) ◽  
pp. 3024-3032 ◽  
Author(s):  
H. Koo ◽  
J. Xiao ◽  
M. I. Klein ◽  
J. G. Jeon

ABSTRACT Streptococcus mutans is a key contributor to the formation of the extracellular polysaccharide (EPS) matrix in dental biofilms. The exopolysaccharides, which are mostly glucans synthesized by streptococcal glucosyltransferases (Gtfs), provide binding sites that promote accumulation of microorganisms on the tooth surface and further establishment of pathogenic biofilms. This study explored (i) the role of S. mutans Gtfs in the development of the EPS matrix and microcolonies in biofilms, (ii) the influence of exopolysaccharides on formation of microcolonies, and (iii) establishment of S. mutans in a multispecies biofilm in vitro using a novel fluorescence labeling technique. Our data show that the ability of S. mutans strains defective in the gtfB gene or the gtfB and gtfC genes to form microcolonies on saliva-coated hydroxyapatite surfaces was markedly disrupted. However, deletion of both gtfB (associated with insoluble glucan synthesis) and gtfC (associated with insoluble and soluble glucan synthesis) is required for the maximum reduction in EPS matrix and biofilm formation. S. mutans grown with sucrose in the presence of Streptococcus oralis and Actinomyces naeslundii steadily formed exopolysaccharides, which allowed the initial clustering of bacterial cells and further development into highly structured microcolonies. Concomitantly, S. mutans became the major species in the mature biofilm. Neither the EPS matrix nor microcolonies were formed in the presence of glucose in the multispecies biofilm. Our data show that GtfB and GtfC are essential for establishment of the EPS matrix, but GtfB appears to be responsible for formation of microcolonies by S. mutans; these Gtf-mediated processes may enhance the competitiveness of S. mutans in the multispecies environment in biofilms on tooth surfaces.


Author(s):  
N.M. Devyatkina ◽  
N.O. Bobrova ◽  
E.M. Vazhnichaya

The oral cavity contains a large number of bacteria, some of which are involved in the development of caries and periodontitis (S. mutans, S. sobrinus, Lactobacilli spp, P. intermedia, P. gingivalis, and T. forythus). The disadvantages of existing antiseptics used in dentistry necessitate the study of antibacterial properties of herbal medicines, and, in particular, of essential oils. The aim of this review is to provide the analysis of literature sources from PubMed and Google Scholar databases related to the effects of essential oils of cloves, mint, thyme, eucalyptus, tea tree and their components on cariogenic and periodontopathic microflora. It was found out that the most in vitro studies evaluated the effects of essential oils or isolated compounds (eugenol, menthol, thymol, carvacrol, eucalyptol, and terpinene-4-ol) on S. mutans, which is considered to be the most cariogenic of oral streptococci, and the researchers limited to defining the susceptibility of the microorganism and effects on biofilm formation. Only in a few studies, the effects of essential oils on the virulence factors of oral pathogens, in particular glycosyl transferase, are represented. Clinical trials of essential oils, their components and combinations confirm the therapeutic potential of these agents in vivo, but raise the question of their effectiveness, taking into account the short-term action, which does not exceed the potency of chlorhexidine. Essential oils of cloves, mint, thyme, eucalyptus, tea tree and their components should be used for treating caries and periodontitis. They are also promising when used as agents of the oral care products, preservatives of the dental medicinal forms, and as remedies for halitosis. With a rational prescription, essential oils can be useful in improving the quality of dental treatment and preventive procedures.


1994 ◽  
Vol 8 (2) ◽  
pp. 272-277 ◽  
Author(s):  
G. Rølla ◽  
J.E. Ellingsen ◽  
D. Gaare

Polydimethylsiloxane (silicone oil) has an extremely low surface tension: It spreads over solid surfaces and forms a tenacious film which is hydrophobic and water-repellent. It is known that this liquid binds to hydroxyapatite and to dental enamel and changes the properties of these solids. It has been suggested that silicone oil may be applied to teeth and serve as a reservoir of lipid-soluble antibacterial substances which presumably will be slowly released into saliva due to their low solubility in water. The present paper reviews recent papers where this hypothesis is tested in vitro and in vivo. It was first shown that test tubes treated with the combination silicone oil and the lipid-soluble agent triclosan acquired a layer which inhibited bacterial growth in a culture of Streptococcus sobrinus (OMZ 176) which was grown in sucrose. Both growth in the medium and polysaccharide adsorption to the glass wall were inhibited. Silicone oil alone inhibited polysaccharide adsorption to some degree, whereas the growth in the medium was not affected. In a similar clinical plaque-inhibition study, topical application of silicone oil/triclosan to the teeth of a test panel showed marked plaque inhibition, particularly giving an increased number of teeth with scores of 0 (no plaque). In a study where silicone oil and triclosan were incorporated into a toothpaste, improved gingival health was observed after a period of one month. It is concluded that the use of silicone oil/ triclosan in the manner described above represents a new principle in preventive dentistry. The results obtained seem to warrant further experiments with this combination.


2019 ◽  
Vol 87 (12) ◽  
Author(s):  
Yongli Bi ◽  
Qingan Xu ◽  
Lingkai Su ◽  
Jiantao Xu ◽  
Zhongfang Liu ◽  
...  

ABSTRACT We previously demonstrated that recombinant protein PAc could be administered as an anticaries vaccine. However, the relatively weak immunogenicity of PAc limits its application. In the present study, we investigated the effect of two adjuvant combinations of chitosan plus Pam3CSK4 (chitosan-Pam3CSK4) and of chitosan plus monophosphoryl lipid A (chitosan-MPL) in the immune responses to the PAc protein in vivo and in vitro. PAc-chitosan-Pam3CSK4 or PAc-chitosan-MPL promoted significantly higher PAc-specific antibody titers in serum and saliva, inhibited Streptococcus mutans colonization onto the tooth surfaces, and endowed better protection effect with significantly less caries activities than PAc alone. Chitosan-Pam3CSK4 and chitosan-MPL showed no statistically significant differences. In conclusion, our study demonstrated that the chitosan-Pam3CSK4 and chitosan-MPL combinations are promising for anticaries vaccine development.


1989 ◽  
Vol 3 (2) ◽  
pp. 161-167 ◽  
Author(s):  
R.A. Bagramian ◽  
S. Narendran ◽  
M. Ward

A random sample of 206 Michigan children, aged from 9 to 13, were examined for fluorosis from a larger group of 2038 children participating in a dental project. Clinical examinations included caries data (DMFS) and assessment of fluorosis by use of the Tooth Surface Index of Fluorosis (TSIF). Separate examiners were used for each index. The response rate of a questionnaire mailed to parents to gather information on residence histories, use of fluoride supplements, and antibiotics was 78%. The prevalence of fluorosis was about 20% among the respondents. Of the 4868 tooth surfaces examined, 9.2% were affected by fluorosis. In all cases, dental fluorosis was judged as mild, with most occurrences on the posterior teeth. No instances of moderate or severe fluorosis were found. The caries experience of respondents was 1.69 ± 2.73 DMFS. Caries experience does not appear to be significantly related to income, education, or fluoride supplement use. Approximately 52% of respondents were reported to have taken fluoride supplements with various degrees of consistency. Parents' education was positively related to both prevalence of fluorosis (odds ratio = 2.2) and use of fluoride supplements (odds ratio = 2.7). No significant relation was revealed with evidence of fluorosis and use of supplements. This study shows a relatively mild level of dental fluorosis in a sample of children from a non-fluoridated area. Dental fluorosis in this group does not appear to be related to use of fluoride supplements or differences in caries experience.


2020 ◽  
Vol 64 (7) ◽  
Author(s):  
Lukas Page ◽  
Andrew J. Ullmann ◽  
Fabian Schadt ◽  
Sebastian Wurster ◽  
Samuel Samnick

ABSTRACT Invasive pulmonary aspergillosis and mucormycosis are life-threatening complications in immunocompromised patients. A rapid diagnosis followed by early antifungal treatment is essential for patient survival. Given the limited spectrum of biomarkers for invasive mold infections, recent studies have proposed the use of radiolabeled siderophores or antibodies as molecular probes to increase the specificity of radiological findings by nuclear imaging modalities. While holding enormous diagnostic potential, most of the currently available molecular probes are tailored to the detection of Aspergillus species, and their cost-intensive and sophisticated implementation restricts their accessibility at less specialized centers. In order to develop cost-efficient and broadly applicable tracers for pulmonary mold infections, this study established streamlined and high-yielding protocols to radiolabel amphotericin B (AMB) with the gamma emitter technetium-99m (99mTc-AMB) and the positron emitter gallium-68 (68Ga-AMB). The radiochemical purity of the resulting tracers consistently exceeded 99%, and both probes displayed excellent stability in human serum (>98% after 60 to 240 min at 37°C). The uptake kinetics by representative mold pathogens were assessed in an in vitro Transwell assay using infected endothelial cell layers. Both tracers accumulated intensively and specifically in Transwell inserts infected with Aspergillus fumigatus, Rhizopus arrhizus, and other clinically relevant mold pathogens compared with their accumulation in uninfected inserts and inserts infected with bacterial controls. Inoculum-dependent enrichment was confirmed by gamma counting and autoradiographic imaging. Taken together, this pilot in vitro study proposes 99mTc-AMB and 68Ga-AMB to be facile, stable, and specific probes, meriting further preclinical in vivo evaluation of radiolabeled amphotericin B for molecular imaging in invasive mycoses.


2010 ◽  
Vol 21 (6) ◽  
pp. 471-481 ◽  
Author(s):  
Arthur Belém Novaes Jr ◽  
Sérgio Luis Scombatti de Souza ◽  
Raquel Rezende Martins de Barros ◽  
Karina Kimiko Yamashina Pereira ◽  
Giovanna Iezzi ◽  
...  

The biological fixation between the dental implant surfaces and jaw bones should be considered a prerequisite for the long-term success of implant-supported prostheses. In this context, the implant surface modifications gained an important and decisive place in implant research over the last years. As the most investigated topic in, it aided the development of enhanced dental treatment modalities and the expansion of dental implant use. Nowadays, a large number of implant types with a great variety of surface properties and other features are commercially available and have to be treated with caution. Although surface modifications have been shown to enhance osseointegration at early implantation times, for example, the clinician should look for research evidence before selecting a dental implant for a specific use. This paper reviews the literature on dental implant surfaces by assessing in vitro and in vivo studies to show the current perspective of implant development. The review comprises quantitative and qualitative results on the analysis of bone-implant interface using micro and nano implant surface topographies. Furthermore, the perspective of incorporating biomimetic molecules (e.g.: peptides and bone morphogenetic proteins) to the implant surface and their effects on bone formation and remodeling around implants are discussed.


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