			Home About us Contact

Secondary Caries (secondary + caries)

Distribution by Scientific Domains

Medical Sciences	85%

Selected Abstracts

Ability of different restorative materials to prevent in situ secondary caries: analysis by polarized light-microscopy and energy-dispersive X-ray

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2008
Thaís Cachuté Paradella
Secondary caries is the main cause of direct restoration replacement. The purpose of this study was to analyze enamel adjacent to different restorative materials after in situ cariogenic challenge using polarized-light microscopy (PLM), scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDS). Twelve volunteers, with a low level of dental plaque, a low level of mutans streptococci, and normal salivary flow, wore removable palatal acrylic appliances containing enamel specimens restored with Z250 composite, Freedom composite, Fuji IX glass-ionomer cement, or Vitremer resin-modified glass-ionomer for 14 days. Volunteers dripped one drop of 20% sucrose solution (n = 10) or distilled water (control group) onto each specimen 8 times per day. Specimens were removed from the appliances and submitted to PLM for examination of the lesion area (in mm2), followed by dehydration, gold-sputtering, and submission to SEM and EDS. The calcium (Ca) and phosphorus (P) contents were evaluated in weight per cent (%wt). Differences were found between Z250 and Vitremer, and between Z250 and FujiIX, when analyzed using PLM. Energy-dispersive X-ray analysis results showed differences between the studied materials regarding Ca %wt. In conclusion, enamel adjacent to glass-ionomer cement presented a higher Ca %wt, but this material did not completely prevent enamel secondary caries under in situ cariogenic challenge. [source]

Bacterial composition and red fluorescence of plaque in relation to primary and secondary caries next to composite: an in situ study

MOLECULAR ORAL MICROBIOLOGY, Issue 1 2008
R. Z. Thomas
Background/hypothesis:, Secondary caries has been suggested as the main reason for restoration replacement. We hypothesized that more caries-associated bacteria are found on composite resin restoration material, compared to sound tooth tissue. Methods:, Both restored and unrestored dentin and enamel samples were placed in a full denture of eight subjects for 20 weeks. The microbiological composition of approximal plaque and the association between caries-associated bacteria and red autofluorescence of dental plaque was studied. Every 4 weeks the specimens were microradiographed using transversal wavelength independent microradiography (T-WIM). After 1 and 20 weeks red fluorescence pictures and plaque samples were taken. Samples were cultured for total anaerobic counts, mutans streptococci, lactobacilli, candida and Actinomyces odontolyticus. Results:, Lesion depth in the dentin and enamel was positively associated with lactobacilli, and lesion depth in dentin was positively associated with A. odontolyticus, whereas no association was found between mutans streptococci and lesion depth. The red-fluorescent bacteria A. odontolyticus and lactobacilli did not correlate with red-fluorescent plaque, indicating that red fluorescence is probably not caused by a single species of these bacteria. After 20 weeks, a higher proportion of combined mutans streptococci and lactobacilli was found on restored tissue compared to non-restored tissue (P = 0.04). Conclusion:, The higher proportion of caries-associated bacteria on restored tissue indicates that the ecology on the surface of primary lesions differs from that on lesions next to composite, and that secondary caries next to composite may differ from the primary caries process. [source]

Placement and replacement of restorations by selected practitioners

AUSTRALIAN DENTAL JOURNAL, Issue 2 2005
MJ Tyas
Abstract Background: There are few Australian data on the reasons for placement and replacement of restorations, and the extent to which these are carried out in general practice. Methods: A survey was carried out of approximately 100 consecutive restorations placed by each of 28 general dental practitioners. The data were coded and statistically analyzed for various associations. Results: Resin composite was used twice as frequently as amalgam as a restorative material, and nearly four times as often as glass-ionomer cement. Secondary caries was the principal reason for replacing restorations, affecting predominantly amalgam restorations in Class I and Class V cavities. Teeth restored with amalgam fractured nearly twice as often as teeth restored with resin composite. The average ages of amalgam, resin composite and glass- ionomers at replacement were 13.6, 7.1 and 5.7 years respectively. Conclusions: Amalgam has the longest clinical service life, but is associated with more tooth fracture. Secondary caries is the main reason for replacing restorations. The anti-cariogenic effect of glass-ionomer cement is equivocal. [source]

Two-year follow-up of fractured anterior teeth restored with direct composite resin: report of three cases

DENTAL TRAUMATOLOGY, Issue 5 2008
Emre Ozel
Fractures of maxillar central incisors including enamel and dentin were diagnosed. Beveling with diamond bur was performed in all four cases. Dentin was cleaned with tungsten carbid bur. The teeth were etched with 37% phosphoric acid, restored with an adhesive system and microhybrid composite. Finishing and polishing procedures were performed by discs (Sof-Lex) and burs. Restorations were found successful according to modified United States Public Health Service (USPHS) criteria after 2 years in terms of retention, color match, marginal discoloration, secondary caries, marginal adaptation, and surface texture. [source]

Reasons for placement and replacement of restorations in student clinics in Manchester and Athens

EUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 4 2000
V. Deligeorgi
Data on reasons for the placement and replacement of restorations provide insight into patterns of clinical practice. This study investigated reasons for the provision of restorations in student clinics at the Universities of Manchester and Athens. Using the methods first described by Mjör, data were collected in relation to all initial and replacement restorations placed in adult patients in the main teaching clinics in the 2 schools over a 3-month period. The principal reason for intervention was recorded, according to approved treatment plans. Data were collected on 2620 restorations, 1431 (55%) of which were placed in Manchester. Primary caries was the main reason for the placement of initial restorations: 82% in Athens and 48% in Manchester (p<0.001). The principal reason for restoration replacement was secondary caries, accounting for 54% in Manchester and 33% in Athens (p<0.001). Other differences between the schools, included the ratio of initial placement to replacement restorations (Manchester 1:1.1; Athens 1:0.6: p<0.01) and significantly more 2-surface class II restorations having been placed in Manchester (p<0.001). Class III and IV restorations predominated in Athens. It is concluded, despite the acknowledged limitations of the methods employed, that the patterns of placement and replacement of restorations and the use of materials differ between the dental schools of Manchester and Athens. The differences are considered to relate more to local patterns of dental disease and patient selection for student clinics than to any differences in teaching philosophy. Subsequent studies of the type reported, despite acknowledged limitations would provide insight into the impact on patient care of the teaching of new materials, techniques and treatment philosophies. [source]

Ability of different restorative materials to prevent in situ secondary caries: analysis by polarized light-microscopy and energy-dispersive X-ray

Restorations with extensive dentin/enamel-bonded ceramic coverage.

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2001
A 5-year follow-up
The durability of restorations with extensive dentin/enamel-bonded posterior partial and complete ceramic coverages were investigated. The effect of luting with a dual-cured and a self-cured luting agent was also studied. In 110 patients, 182 ceramic coverages (IPS Empress) were placed. In 58 restorations, Syntac was used in combination with the dual-cured resin composite Variolink. In the other restorations luted with the chemically cured resin composite Bisfil 2B, 25 were bonded with Gluma, 57 with Allbond 2, and 42 with Syntac. Of the 182 ceramics, 13 (7.1%) were assessed as non-acceptable after a mean observation period of 4.9 yr (range 4.3,7.5 yr). The reasons for failure were fracture (5), lost restorations (4), secondary caries (3) and endodontic treatment (1). No significant differences in failure rate were seen between the two luting agents or between the three dentin-bonding agents. Ceramic coverages placed on non-vital teeth failed in 9.7% of cases (3/31) and on vital teeth in 6.6% (10/151). The success rate of the dentin-enamel-bonded ceramic coverages reduces the need for a traditional full-coverage therapy and/or post or pin(s) and core placement. The technique investigated showed many clinical advantages such as less destruction of healthy tissue, and avoidance of endodontic treatment and/or deep cervical placement of restoration margins. [source]

Prosthetic crowns and other clinical risk indicators of caries among old-old Swedish adults: Findings from the KEOHS Project

GERODONTOLOGY, Issue 2 2002
Douglas E. Morse
Abstract Objectives: The Kungsholmen Elders Oral Health Study (KEOHS) evaluated the oral health status of generally healthy, community-dwelling persons over the age of 80 living in Kungsholmen, Sweden. This paper explored possible clinical risk indicators of coronal and root caries among the KEOHS subjects. Design: In this cross-sectional study, dentate KEOHS subjects received a caries assessment using defined visual, tactile criteria. Setting: Examinations were carried out in two local clinics by standardized examiners. Subjects: One hundred twenty-nine dentate persons were examined. Main Outcome Measures: The examination identified decayed and filled surfaces, prosthetic crowns, and missing teeth. Results: More root than coronal surfaces had untreated decay, and secondary root caries contributed the greatest number of decayed surfaces. Ninety percent of the examined dentate subjects had at least one prosthetic crown. Root surfaces exposed to crown margins were more likely to have caries than root surfaces not so exposed, particularly among women. The presence of untreated coronal caries (yes/no) was positively associated with having untreated root caries and an intermediate number (14,20) of teeth, but inversely associated with having 4+ prosthetic crowns. Active root caries (yes/no) was positively associated with having untreated coronal caries, 14,20 teeth, and 4+ prosthetic crowns. Nearly 20% of identified root lesions were present at or below the gingival margin, and most (88%) were secondary caries associated with crown margins (65%) or other restorations (23%). Conclusions: Our findings suggest that some dental characteristics, including the presence of prosthetic crowns, are risk indicators for the presence of untreated coronal and root caries. [source]

Bacterial invasion of dentinal tubules beneath apparently intact but hypomineralized enamel in molar teeth with molar incisor hypomineralization

INTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 5 2008
TOBIAS G. FAGRELL
Background., The most common problems for a patient with molar incisor hypomineralization (MIH) are the collapse of enamel and cavitations, loss of fillings, and secondary caries, but most of all, severe hypersensitivity. Objective., The aim of this paper was therefore to histologically study possible bacterial invasion of dentinal tubules beneath apparently intact, but hypomineralized enamel in permanent molars with MIH. Material and methods., Five extracted permanent first molars diagnosed with MIH were fixated, demineralized, and sagittally serially sectioned in a bucco-lingual direction in a microtome with a thickness of 4,5 µm. Sections were stained with a modified Brown and Benn staining for bacteria, unstained sections were analysed in field emission SEM. Results., Stained sections from the cuspal areas, below the hypomineralized enamel, the staining indicated the presence of bacteria in the dentinal tubules. The HTX staining showed that the pulp in sections without any findings was normal and free from bacteria or infiltrates from inflammatory cells. In sections where bacteria were found in the cuspal areas or deeper in the dentin, a zone of reparative dentin was found, and in sections from one tooth, the coronal pulp showed an inflammatory reaction with inflammatory cells. In sections adjacent to those without any bacterial staining, the SEM analyses revealed empty dentinal tubules without any odontoblast processes or signs of bacteria. When odontoblast processes were found, the dentinal tubules were filled with bacteria located on the surface of the odontoblast processes. In some areas, a large number of tubules were found with bacteria. No bacteria were found close to the pulp. The odontoblast processes appeared larger in areas where bacteria were found. Conclusions., The presence of bacteria in the dentinal tubules and inflammatory reactions in the pulp indicate that oral bacteria may penetrate through the hypomineralized enamel into the dentin, thus possibly contribute to hypersensitivity of teeth with MIH. [source]

Influence of local anaesthesia on the quality of class II glass ionomer restorations

INTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 4 2007
NANDA VAN DE HOEF
Objective., To investigate the influence of local anaesthesia on the quality of class II glass ionomer restorations with discomfort as cofactor. Material and methods., The study population consisted of 6- to 7-year-old schoolchildren in Paramaribo and its environs. To be included, each child needed to have a proximally situated cavity in a primary molar that was accessible to hand instruments and where no pulp exposure was expected. They were randomly divided into four treatment groups: conventional method with and without local anaesthesia and atraumatic restorative treatment method (ART) with and without local anaesthesia. The restoration quality was scored using the evaluation criteria for ART restorations (successful if restoration is correct or has a minor defect and fails if defects are larger than 0.5 mm, if secondary caries is observed, if the restoration is fractured, partly or totally lost or if the pulp is involved) at 6 and 30 months after treatment. The extent of discomfort was registered by assessing the behaviour (modified Venham score) and observing the heart rate during treatment. Results., For this study 153 children were treated with hand instruments (ART) and 146 children with rotary instruments (conventional method). A total of 198 restorations were evaluated during follow-up periods. There were no significant differences in patient discomfort between the ART and the conventional group and between the anaesthesia and the non-anaesthesia group. The conventional restorations demonstrated significantly higher success rates than ART restorations after 6 (P = 0.001) and 30 months (P = 0.032). There were no significant differences in success rate between the anaesthesia and the non-anaesthesia group. Conclusion., Local anaesthesia has no influence on discomfort during treatment. Furthermore, discomfort during treatment does not affect the success rate of restorations. [source]

Conventional versus resin-modified glass-ionomer cement for Class II restorations in primary molars.

INTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 1 2003
A 3-year clinical study
Summary. Objective. To compare the clinical performance of two glass-ionomer cements (GICs)for Class II restorations in primary molars: a conventional cement (Fuji II®) and a resin-modified cement (Vitremer®). Design. Split mouth and random assignment to the two materials were used for the majority of the molars. Sample and methods. Forty consecutive 4,7-year-old children were included. One operator made 115 restorations: 53 with Vitremer and 62 with Fuji II. The restorations were evaluated clinically, radiographically and from colour photographs. Results. The cumulative success rate of the Vitremer restorations was 94% and that of the Fuji II restorations 81%. The difference is statistically significant. The risk of a failed restoration was more than five times higher with Fuji II than with Vitremer as the restorative material. Of the 13 unsuccessful restorations, seven had lost their retention, four had secondary caries, and two were fractured. Conclusions. The resin-modified GIC offered advantages over the conventional GIC for restoring approximal caries in primary molars. [source]

Antibacterial activity of dental composites containing zinc oxide nanoparticles,

JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2010
Berdan Aydin Sevinç
Abstract The resin-based dental composites commonly used in restorations result in more plaque accumulation than other materials. Bacterial biofilm growth contributes to secondary caries and failure of resin-based dental composites. Methods to inhibit biofilm growth on dental composites have been sought for several decades. It is demonstrated here that zinc oxide nanoparticles (ZnO-NPs) blended at 10% (w/w) fraction into dental composites display antimicrobial activity and reduce growth of bacterial biofilms by roughly 80% for a single-species model dental biofilm. Antibacterial effectiveness of ZnO-NPs was assessed against Streptococcus sobrinus ATCC 27352 grown both planktonically and as biofilms on composites. Direct contact inhibition was observed by scanning electron microscopy and confocal laser scanning microscopy while biofilm formation was quantified by viable counts. An 80% reduction in bacterial counts was observed with 10% ZnO-NP-containing composites compared with their unmodified counterpart, indicating a statistically significant suppression of biofilm growth. Although, 20% of the bacterial population survived and could form a biofilm layer again, 10% ZnO-NP-containing composites maintained at least some inhibitory activity even after the third generation of biofilm growth. Microscopy demonstrated continuous biofilm formation for unmodified composites after 1-day growth, but only sparsely distributed biofilms formed on 10% ZnO-NP-containing composites. The minimum inhibitory concentration of ZnO-NPs suspended in S. sobrinus planktonic culture was 50 ,g mL,1. ZnO-NP-containing composites (10%) qualitatively showed less biofilm after 1-day-anaerobic growth of a three-species initial colonizer biofilm after being compared with unmodified composites, but did not significantly reduce growth after 3 days. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010. [source]

Effects of incorporating nanosized calcium phosphate particles on properties of whisker-reinforced dental composites,,

JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007
Hockin H. K. Xu
Abstract Clinical data indicate that secondary caries and restoration fracture are the most common problems facing tooth restorations. Our ultimate goal was to develop mechanically-strong and caries-inhibiting dental composites. The specific goal of this pilot study was to understand the relationships between composite properties and the ratio of reinforcement filler/releasing filler. Nanoparticles of monocalcium phosphate monohydrate (MCPM) were synthesized and incorporated into a dental resin for the first time. Silicon carbide whiskers were fused with silica nanoparticles and mixed with the MCPM particles at MCPM/whisker mass ratios of 1:0, 2:1, 1:1, 1:2, and 0:1. The composites were immersed for 1,56 days to measure Ca and PO4 release. When the MCPM/whisker ratio was changed from 0:1 to 1:2, the composite flexural strength (mean ± SD; n = 5) decreased from 174 ± 26 MPa to 138 ± 9 MPa (p < 0.05). A commercial nonreleasing composite had a strength of 112 ± 14 MPa. When the MCPM/whisker ratio was changed from 1:2 to 1:1, the Ca concentration at 56 days increased from 0.77 ± 0.04 mmol/L to 1.74 ± 0.06 mmol/L (p < 0.05). The corresponding PO4 concentration increased from 3.88 ± 0.21 mmol/L to 9.95 ± 0.69 mmol/L (p < 0.05). Relationships were established between the amount of release and the MCPM volume fraction vMCPM in the resin: [Ca]= 42.9 v, and [PO4] = 48.7 v. In summary, the method of combining nanosized releasing fillers with reinforcing fillers yielded Ca- and PO4 -releasing composites with mechanical properties matching or exceeding a commercial stress-bearing, nonreleasing composite. This method may be applicable to the use of other Ca,PO4 fillers in developing composites with high stress-bearing and caries-preventing capabilities, a combination not yet available in any dental materials. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source]