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ABSTRACT: OBJECTIVES: The objective of this systematic review was to evaluate the effects of smoking on the survival rate of dental implants placed in areas of maxillary sinus floor augmentation. MATERIAL AND METHODS: The Cochrane Oral Health Group's Trials Register (CENTRAL), MEDLINE and EMBASE were searched in duplicate up to, and including, October 2012 without language restrictions. Studies were considered eligible for inclusion if they involved the treatment of smokers and non-smokers with titanium implants and sinus floor elevation procedures. The Newcastle-Ottawa Scale and the Cochrane Collaboration's quality assessment tool were used for the assessment of the risk of bias in included studies. Random effects meta-analyses were used to assess the number of implants lost in smokers vs. number of implants lost in non-smokers. RESULTS: Of 3360 potentially eligible papers, eight studies were included. More than half (62.5%) of the studies found that smoking adversely affects implant survival in sites of sinus floor augmentation. Similarly, the pooled analysis indicated a statistically significantly increased risk of implant failure in smokers when the outcomes of all studies available to be included into meta-analysis were evaluated [RR: 1.87 (95% CI: 1.35, 2.58), P = 0.0001]. Conversely, a subgroup analysis including only prospective studies (3 studies) did not reveal significant differences in implant failure between smokers and non-smokers [RR: 1.55 (95% CI: 0.91, 2.65), P = 0.11]. CONCLUSIONS: Although smoking was associated with implant failure in most of individual studies and in the overall meta-analysis, the detrimental effect of smoking was not confirmed when only prospective data were assessed.
Clinical Oral Implants Research 05/2013; · 2.51 Impact Factor
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ABSTRACT: This study evaluated the effects of the photoactivation source and restorative material on the development of caries-like lesions on human enamel after an in vitro pH challenge. Enamel cavities were prepared in 36 blocks, which were assigned to two groups according to the restorative material: resin-modified glass ionomer (RMGI) and composite resin (CR). Samples were exposed to quartz-tungsten-halogen lamp, argon-ion laser, or light-emitting diode (n = 6). The Knoop microhardness (KHN) values of the top surface of all materials were evaluated. Restored enamel blocks were thermocycled and subjected to 10 demineralization-remineralization cycles at 37°C. KHN analysis of the superficial enamel was performed by four indentations located 100 mm from the restoration margin. The material KHN was not affected by the photoactivation source. No significant difference in KHN was noted between CR and RMGI. The enamel surface around RMGI exhibited a higher KHN (272.8 KHN) than the enamel around CR (93.3 KHN), regardless of the photoactivation source. Enamel demineralization around the dental restoration was not influenced by the photoactivation source. Less enamel demineralization was observed around the RMGI than around the CR restoration.
Brazilian oral research 03/2013;
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ABSTRACT: PURPOSE: This prospective, controlled split-mouth study evaluated the stability of dental implants placed in the augmented mandibular areas with alveolar segmental "sandwich" osteotomies using nonceramic hydroxyapatite (ncHA) or autogenous bone. MATERIAL AND METHODS: This study included 11 bilaterally partially edentulous mandibular patients in a split-mouth design. Alveolar augmentation osteotomies were performed bilaterally with interpositional ncHA graft (test group) or interpositional intraoral autogenous bone graft (control group). After 6 months of healing, four implants (two implants in each side) were placed in each patient. Forty-four implants were inserted and loaded after 6-month healing period. At 1-year follow-up, radiographic, prosthetic, and resonance frequency analysis parameters were assessed. Success criteria included absence of pain, sensitivity, suppuration, and implant mobility; absence of continuous peri-implant radiolucency; and distance between the implant shoulder and the first visible bone contact (DIB) < 2 mm. RESULTS: After a 1-year loading period, the overall implant survival rate was 95.45%, with two implant losses (one of each group). Among the surviving implants (42 out of 44), two did not fulfill the success criteria; therefore, the implant success was 90.90%. DIB was 0.71 ± 0.70 and 0.84 ± 0.72 mm for ncHA and autogenous bone grafts, respectively (p > .05). Implant stability measurements were similar between the groups during the 12-month follow-up (p > .05). CONCLUSION: Within the limits of this study, the implants placed either in sites augmented with ncHA or autogenous bone seem to represent a safe and successful procedure, at least, after 12-month follow-up.
Clinical Implant Dentistry and Related Research 11/2012; · 3.53 Impact Factor
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ABSTRACT: The objective of this study was to evaluate in vitro light activation of the nano-filled resin composite Vita shade A1 and
A3 with a halogen lamp (QTH) and argon ion laser by Knoop microhardness profile. Materials and methods: Specimens of nanofilled
composite resin (Z350-3M-ESPE) Vita shade A1 and A3 were prepared with a single increment inserted in 2.0-mm-thick and 3-mm
diameter disc-shaped Teflon mold. The light activation was performed with QTH for 20s (with an intensity of approximately
1,000mW/cm2 and 700mW/cm2) and argon ion laser for 10s (with a power of 150mW and 200mW). Knoop microhardness test was performed after 24h and
6months. The specimens were divided into the 16 experimental groups (n = 10), according to the factors under study: photoactivation form, resin shade, and storage time. Knoop microhardness data
was analyzed by a factorial ANOVA and Tukey´s tests at the 0.05 level of significance. Results: Argon ion laser was not able
to photo-activate the darker shade of the nanofilled resin composite evaluated but when used with 200mW it can be as effective
as QTH to photo-activate the lighter shade with only 50% of the time exposure. After 6 months storage, an increase in the
means of Knoop microhardness values were observed. Conclusions: Light-activation significantly influenced the Knoop microhardness
values for the darker nanofilled resin composite.
KeywordsRestorative dental material-Argon ion laser-Halogen unit-Long-term storage-Shade-Microhardness
Lasers in Medical Science 04/2012; 25(6):829-834. · 2.00 Impact Factor
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ABSTRACT: The objective of this study was to evaluate the influence of Er:YAG laser (λ = 2.94 μm) on microtensile bond strength (μTBS) and superficial morphology of bovine dentin bleached with 16% carbamide peroxide. Forty bovine teeth blocks (7 × 3 × 3 mm(3)) were randomly assigned to four groups: G1- bleaching and Er:YAG irradiation with energy density of 25.56 J/cm(2) (focused mode); G2 - bleaching; G3 - no-bleaching and Er:YAG irradiation (25.56 J/cm(2)); G4 - control, non-treated. G1 and G2 were bleached with 16% carbamide peroxide for 6 h during 21 days. Afterwards, all blocks were abraded with 320 to 600-grit abrasive papers to obtain flat standardized dentin surfaces. G1 and G3 were Er:YAG irradiated. Blocks were immediately restored with 4-mm-high composite resin (Adper Single Bond 2, Z-250-3 M/ESPE). After 24 h, the restored blocks (n = 9) were serially sectioned and trimmed to an hour-glass shape of approximately 1 mm(2) at the bonded interface area, and tested in tension in a universal testing machine (1 mm/ min). Failure mode was determined at a magnification of 100× using a stereomicroscope. One block of each group was selected for scanning electron microscope (SEM) analysis. μTBS data was analyzed by two-way ANOVA and Tukey test (α = 0.05). Mean bond strengths (SD) in MPa were: G1- 32.7 (5.9)(A); G2- 31.1 (6.3)(A); G3- 25.2 (8.3)(B); G4- 36.7 (9.9).(A) Groups with different uppercase letters were significantly different from each other (p < .05). Enamel bleaching procedure did not affect μTBS values for dentin adhesion. Er:YAG laser irradiation with 25.56 J/cm(2) prior to adhesive procedure of bleached teeth did not affect μTBS at dentin and promoted a dentin surface with no smear layer and opened dentin tubules observed under SEM. On the other hand, Er:YAG laser irradiation prior to adhesive procedure of non-bleached surface impaired μTBS compared to the control group.
Lasers in Medical Science 01/2012; 27(1):31-8. · 2.00 Impact Factor
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Jamil A Shibli,
Carlo Mangano,
Francesco Mangano,
José A Rodrigues, Alessandra Cassoni,
Karen Bechara,
Jose Divino,
B Ferreia,
Alexandre M Dottore,
Giovanna Iezzi,
Adriano Piattelli
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ABSTRACT: Objective: Direct laser metal forming (DLMF) is a metal forming procedure in which a high power laser beam is directed on a metal powder bed and programmed to fuse particles according to a CAD file, thus generating a thin metal layer. This histologic study evaluated the bone-to-implant contact (BIC%) around immediately loaded DLMF transitional implants retrieved after 2 months from posterior human maxillae. Material and Methods: 12 totally edentulous subjects (mean age 66.14±2.11 years) received DLMF transitional implants divided in: immediately loaded (IL=12 implants) and unloaded implants (UI=12 implants). These transitional implants were placed between conventional implants to support the interim complete maxillary denture during the healing period. After 8 weeks, the transitional implants and the surrounding tissue were removed and prepared for histomorphometric analysis. Results: Around all retrieved implants, mature woven preexisting bone, lined by newly-formed bone in early stages of maturation in both groups were found. Histometric evaluation indicated that the mean BIC% ranged between 45.20±7.68% and 34.10±7.85% for IL and UI, respectively (p<0.05).
Journal of Periodontology 01/2012; · 2.60 Impact Factor
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ABSTRACT: The wide use of dental bleaching treatment has brought concern about the possible effects of hydrogen peroxide on dental tissue and restorative materials. The objective of this study was to evaluate in vitro the effect of nightguard bleaching on the surface roughness of dental ceramics after different periods of bleaching treatment. Fifteen specimens of 5 × 3 × 1 mm were created with three dental ceramics following the manufacturers' instructions: IPS Classic (Ivoclar-Vivadent); IPS d.Sign (Ivoclar-Vivadent); and VMK-95 (Vita). A profilometer was used to evaluate baseline surface roughness (Ra values) of all ceramics by five parallel measurements with five 0.25 mm cut off (Λc) at 0.1 mm/s. Afterwards, all specimens were submitted to 6-h daily bleaching treatments with 10% or 16% carbamide peroxide (Whiteness- FGM) for 21 days, while control groups from each ceramic system were stored in artificial saliva. The surface roughness of all groups was evaluated after 18 h, 42 h, 84 h, and 126 h of bleaching treatment. The surface roughness of each specimen (n = 5) was based on the mean value of five parallel measurements in each time and all data were submitted to two-way repeated measures ANOVA and Tukey's post-hoc test (α = 0.05). No significant differences in ceramic surface roughness were observed between untreated and bleached ceramic surfaces, regardless of bleaching intervals or bleaching treatments. This study provided evidence that at-home bleaching systems do not cause detrimental effects on surface roughness of dental ceramics.
Brazilian oral research 10/2011; 25(5):453-8.
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ABSTRACT: The aim of this study was to evaluate the degree of conversion by Knoop microhardness (KHN) and FT-Raman spectroscopy (FTIR) of one nanofilled (Filtek Supreme-3M-ESPE [FS]) and one microhybrid composite (Charisma-Heraeus-Kulzer [CH]), each with different opacities, namely enamel, dentin, and translucent, which were photo-activated by a quartz-tungsten-halogen lamp (QTH) and a light-emitting diode (LED). Resin was bulk inserted into a disc-shaped mold that was 2.0 mm thick and 4 mm in diameter, obtaining 10 samples per group. KHN and FTIR values were analyzed by two-way ANOVA and Tukey's tests (α = 0.05). Nanofilled resin activated by a LED presented higher microhardness values than samples activated by a QTH for dentin opacity (p < 0.05). The microhybrid resin showed no differences in KHN or FTIR values with different activation sources or opacity. The nanofilled dentin and enamel resins showed lower FTIR values than the translucent resin. The KHN values of the translucent resins were not influenced by the light source.
Brazilian oral research 06/2011; 25(3):267-73.
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ABSTRACT: The objective of this study was to evaluate the influence of different Er:YAG laser (λ = 2.94 μm) energy parameters on the microtensile bond strength (μTBS) and superficial morphology of bovine enamel bleached with 16% carbamide peroxide.
Laser irradiation could improve adhesion to bleached enamel surfaces.
Sixty bovine enamel blocks (7 × 3 × 3 mm(3)) were randomly assigned to six groups according to enamel preparation procedures (n = 10): G1-bleaching and Er:YAG laser irradiation with 25.52 J/cm(2) (laser A, LA); G2-bleaching and Er:YAG laser irradiation with 4.42 J/cm(2) (laser B, LB); G3-bleaching; G4-Er:YAG laser irradiation with 25.52 J/cm(2); G5-Er:YAG laser irradiation with 4.42 J/cm(2); G6-control, no treatment. G1 to G3 were bleached for 6 h during 21 days. Afterwards, enamel surfaces in all groups were slightly abraded with 600-grit SiC papers and G1, G2, G4 and G5 were irradiated according to each protocol. Enamel blocks were then restored with an etch-and-rinse adhesive system and a 4-mm thick composite buildup was made in two increments (n = 9). After 24 h, restored blocks were serially sectioned with a cross-section area of ∼1 mm(2) at the bonded interface and tested in tension in a universal testing machine (1 mm/min). Failure mode was determined at a magnification of x100 using a stereomicroscope. One treated block of each group was selected for scanning electron microscopy (SEM) analysis. μTBS data were analyzed by two-way ANOVA and no statistical differences were observed among groups.
Mean bond strengths (SD) in MPa were: G1-30.4(6.2); G2-27.9(8.5); G3-32.3(3.9); G4-23.7(5.8); G5-29.3(6.0); G6-29.1(6.1). A large number of adhesive failures was recorded for bleached and irradiated enamel surfaces.
Bleached enamel surfaces μTBS values were not significantly different from those of unbleached enamel. Even though Er:YAG laser irradiation with both parameters had no influence on μTBS for bleached and unbleached enamel, SEM analysis revealed that Er:YAG laser irradiation with 25.52 J/cm(2) should not be recommended, as enamel ablation was observed, whereas irradiation with 4.42 J/cm(2) did not promote any remarkable changes on enamel surface.
Photomedicine and laser surgery 02/2011; 29(8):551-8. · 1.76 Impact Factor
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ABSTRACT: Recent studies have shown that direct laser metal sintering (DLMS) produces structures with complex geometry and consequently that allow better osteoconductive properties. The aim of this patient report was to evaluate the early bone response to DLMS implant surface retrieved from human jaws. Four experimental DLMS implants were inserted in the posterior mandible of four patients during conventional dental implant surgery. After 8 weeks, the micro-implants and the surrounding tissue were removed and prepared for scanning electron microscopy (SEM) and histomorphometric analysis to evaluate the bone-implant interface. The SEM and EDX evaluations showed a newly formed tissue composed of calcium and phosphorus. The bone-to-implant contact presented a mean of 60.5 ± 11.6%. Within the limits of this patient report, data suggest that the DLMS surfaces presented a close contact with the human bone after a healing period of 8 weeks.
Lasers in Medical Science 01/2011; 26(1):133-8. · 2.00 Impact Factor
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ABSTRACT: The objective of this study was to evaluate the effects of photoactivation source
on human enamel demineralization by Knoop microhardness analysis (KHN) after in vitro pH
challenge. Human teeth were sectioned in thirty-six blocks, cavities were prepared, and assigned
into 2 groups according to restorative material (n=18): resin-modified glass ionomer material
(IVMR) and composite resin (CR). Cavities were restored with RMGI or RC, which were exposed
to quartz-tungsten-halogen lamp (QTH), argon-ion laser (LA), or Light Emitting Diode (LED) (n=6).
Restored enamel blocks were thermal challenge and submitted to demineralization cycles to
induce enamel demineralization. Restored blocks were longitudinally sectioned in the middle and
Knoop hardness (in KHN) analysis of subsuperficial caries-like lesions was performed at 30 mm,
60 mm, 90 mm, 120 mm,150 mm, 180 mm, and 210 mm below the surface and 100 mm, 200 mm and
400 mm distant from the restored cavity. Data of subsuperficial KHN values were evaluated by
4-way ANOVA and Tukey’s post-hoc test (α<0.05). ANOVA demonstrated significant difference for
‘material’; ‘photoactivation source’ and ‘distance’ (p< 0.0001). The results of material factor were:
IVMR: 327.3A and RC: 210.4B. There were statistical differences for ‘photoactivation source’ and
‘distance’ interaction (p<000001). The results (KHN) of 100mm distance were: QTH: 361.6A; LED:
306.0B; LA: 206.5C. The results (KHN) of 200mm distance were: QTH: 316.7A; LED: 259.5B;
LA: 269.2B. The results (KHN) of 400mm distance were: QTH: 259.5A; LED: 181.6B; LA: 259.1A.
There was less human enamel demineralization around IVMR restoration than around RC. The
depth of enamel caries lesions was similar for the restorative materials. Argon ion photoactivation
led to similar benefits of QTH activation on enamel demineralization by 200 μm distance from
restored cavity.
Saude. 01/2011; 5(2):31 - 45.
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ABSTRACT: The understanting of the dental fluorosis process, that begins with enamel maturation, is important to Dentistry students, since fluoride has drastically decreased the incidence of caries in several population groups, with a resultant increase in fluorosis prevalence and severity, as shown in literature.
The objective of this paper is to report the changes in the level of knowledge about dental fluorosis of undergraduate Dentistry students at Guarulhos University.
One hundred and twenty-four undergraduate students enrolled in the first and second semester (2008) and seventh semester (2008) were evaluated. The data was obtained through questionnaires with dichotomic questions (true and false) and an alternative to evaluate whether the subject had been presented in the classroom. The data obtained was submitted to statistical analysis using the Chi-square test (α=0.05).
When evaluating the first semester students, differences were verified in numbers of the questions assigned with the alternatives true or false, when compared with seventh semester students (p<0.001). However, there were no differences when the same questionnaire was applied to the first semester students after six months (p=0.358).
It is possible to conclude that the six months period was insufficient to increase the level of knowledge about dental fluorosis, and when the students beginning and concluding the dentistry course were compared, there was an increase in the number of correctly assigned true or false questions in the latter group.
North American journal of medical sciences. 08/2010; 2(8):371-5.
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ABSTRACT: The objective of this study was to evaluate the influence of various pulse widths with different energy parameters of erbium:yttrium-aluminum-garnet (Er:YAG) laser (2.94 mum) on the morphology and microleakage of cavities restored with composite resin. Identically sized class V cavities were prepared on the buccal surfaces of 54 bovine teeth by high-speed drill (n = 6, control, group 1) and prepared by Er:YAG laser (Fidelis 320A, Fotona, Slovenia) with irradiation parameters of 350 mJ/ 4 Hz or 400 mJ/2 Hz and pulse width: group 2, very short pulse (VSP); group 3, short pulse (SP); group 4, long pulse (LP); group 5, very long pulse (VLP). All cavities were filled with composite resin (Z-250-3 M), stored at 37 degrees C in distilled water, polished after 24 h, and thermally stressed (700 cycles/5-55 degrees C). The teeth were impermeabilized, immersed in 50% silver nitrate solution for 8 h, sectioned longitudinally, and exposed to Photoflood light for 10 min to reveal the stain. The leakage was evaluated under stereomicroscope by three different examiners, in a double-blind fashion, and scored (0-3). The results were analyzed by Kruskal-Wallis test (P > 0.05) and showed that there was no significant differences between the groups tested. Under scanning electron microscopy (SEM) the morphology of the cavities prepared by laser showed irregular enamel margins and dentin internal walls, and a more conservative pattern than that of conventional cavities. The different power settings and pulse widths of Er:YAG laser in cavity preparation had no influence on microleakage of composite resin restorations.
Lasers in Medical Science 10/2009; 25(6):881-9. · 2.00 Impact Factor
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ABSTRACT: This in vitro study evaluated the influence of cavity preparation using the Er:YAG laser and restorative materials containing fluoride on preventing caries lesions.
It has been suggested that cavity preparation using the Er:YAG laser has a potential for improving resistance to secondary caries on enamel.
Forty unerupted human third molars teeth were sectioned into 72 blocks of dental enamel and distributed into two groups to prepare cavities measuring (1.6 mm diameter) with diamond burs (DB) or Er:YAG laser (LA; 6 Hz, 300 mJ, 47 J/cm(2)). After that, each group was divided into three subgroups and restored with a glass-ionomer cement (GI), a resin-modified glass-ionomer (RM), or a composite resin (CR). Blocks were thermal cycled and submitted to a pH challenge to develop artificial caries-like lesions. Lesions were evaluated by Knoop microhardness test. An average of four indentations was used. Statistical analyses were performed by ANOVA followed by Tukey's test.
The results (in Knoop hardness number) for DB cavity preparation were GI, 235.5 (+/-75.5); RM, 137.1 (+/-64.1); and CR, 39.3 (+/-26.5). For LA cavity preparation, the results were GI, 410.0 (+/-129.7); RM, 310.3 (+/-119.5); and CR, 96.4 (+/-57.4).
There was less development of caries lesion around LA-prepared cavities than around the DB-prepared cavities; however, no synergistic cariostatic effect was observed between the Er:YAG laser and glass ionomer cement.
Photomedicine and laser surgery 09/2009; 27(5):729-34. · 1.76 Impact Factor
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ABSTRACT: The objective of this in vitro study was to compare the degree of microleakage of composite restorations performed by lasers and conventional drills associated with two adhesive systems.
Sixty bovine teeth were divided into 6 groups (n = 10). The preparations were performed in groups 1 and 2 with a high-speed drill (HD), in groups 3 and 5 with Er:YAG laser, and in groups 4 and 6 with Er,Cr:YSGG laser. The specimens were restored with resin composite associated with an etch-and-rinse two-step adhesive system (Single Bond 2 [SB]) (groups 1, 3, 4) and a self-etching adhesive (One-Up Bond F [OB]) (groups 2, 5, 6). After storage, the specimens were polished, thermocycled, immersed in 50% silver nitrate tracer solution, and then sectioned longitudinally. The specimens were placed under a stereomicroscope (25X) and digital images were obtained. These were evaluated by three blinded evaluators who assigned a microleakage score (0 to 3). The original data were submitted to Kruskal-Wallis and Mann-Whitney statistical tests.
The occlusal/enamel margins demonstrated no differences in microleakage for all treatments (p > 0.05). The gingival/dentin margins presented similar microleakage in cavities prepared with Er:YAG, Er,Cr:YSGG, and HD using the etch-and-rinse two-step adhesive system (SB) (p > 0.05); otherwise, both Er:YAG and Er,Cr:YSGG lasers demonstrated lower microleakage scores with OB than SB adhesive (p < 0.05).
The microleakage score at gingival margins is dependent on the interaction of the hard tissue removal tool and the adhesive system used. The self-etching adhesive system had a lower microleakage score at dentin margins for cavities prepared with Er:YAG and Er,Cr:YSGG than the etch-and-rinse two-step adhesive system.
The journal of adhesive dentistry 06/2009; 11(3):221-9. · 1.11 Impact Factor
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ABSTRACT: The purpose of this study was to evaluate in vitro the Knoop microhardness (Knoop hardness number [KHN]) and the degree of conversion using FT-Raman spectroscopy of a light-cured microhybrid resin composite (Z350-3M-ESPE) Vita shade A3 photopolymerized with a halogen lamp or an argon ion laser.
Optimal polymerization of resin-based dental materials is important for longevity of restorations in dentistry.
Thirty specimens were prepared and inserted into a disc-shaped polytetrafluoroethylene mold that was 2.0 mm thick and 3 mm in diameter. The specimens were divided into three groups (n = 10 each). Group 1 (G1) was light-cured for 20 sec with an Optilux 501 halogen light with an intensity of 1000 mW/cm(2). Group 2 (G2) was photopolymerized with an argon laser with a power of 150 mW for 10 sec, and group 3 (G3) was photopolymerized with an argon laser at 200 mW of power for 10 sec. All specimens were stored in distilled water for 24 h at 37 degrees C and kept in lightproof containers. For the KHN test five indentations were made and a depth of 100 microm was maintained in each specimen. One hundred and fifty readings were obtained using a 25-g load for 45 sec. The degree of conversion values were measured by Raman spectroscopy. KHN and degree of conversion values were obtained on opposite sides of the irradiated surface. KHN and degree of conversion data were analyzed by one-way ANOVA and Tukey tests with statistical significance set at p < 0.05.
The results of KHN testing were G1 = 37.428 +/- 4.765; G2 = 23.588 +/- 6.269; and G3 = 21.652 +/- 4.393. The calculated degrees of conversion (DC%) were G1 = 48.57 +/- 2.11; G2 = 43.71 +/- 3 .93; and G3 = 44.19 +/- 2.71.
Polymerization with the halogen lamp (G1) attained higher microhardness values than polymerization with the argon laser at power levels of 150 and 200 mW; there was no difference in hardness between the two argon laser groups. The results showed no statistically significant different degrees of conversion for the polymerization of composite samples with the two light sources tested.
Photomedicine and laser surgery 12/2008; 26(6):531-9. · 1.76 Impact Factor
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ABSTRACT: The aim of this study was to evaluate the microbiota and surface of failed titanium dental implants from 4 manufacturers. Twelve mobile dental implants were retrieved from 10 smokers after 3 to 10 years of functional loading. Before implant removal, microbial samples were taken and evaluated using polymerase chain reaction. After implant removal, analyses of the failed implant surfaces were performed using scanning electron microscopy and energy-dispersive spectrometer x-ray. Periodontal pathogens such as Aggregactibacter actinomycetemcomitans, Campylobacter rectus, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola were detected in all implants in different proportions. Surface analysis showed varying degrees of surface roughness between the samples and the presence of proteinaceous material, appearing mainly as dark stains. Foreign carbon, oxygen, sodium, calcium, aluminum, and silicon elements were also found. Although no material-related causes of implant failure were detected, several periodontal pathogens were identified independently of the surface topography or manufacturer.
Journal of Oral Implantology 02/2007; 33(4):232-8. · 1.53 Impact Factor
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ABSTRACT: The aim of this work was to study one dentin-bonding system associated with posterior teeth restorative composite resin by means of tensile bond strength tests varying the technique of polymerization: visible light and argon laser.
Previous studies have demonstrated the ability of the argon laser to polymerize light-activated materials.
Sixty specimens were prepared by grinding the labial surface of bovine teeth embedded in acrylic resin. The dentin bonding system used was Single Bond (3M), which has a poliacenoic acid copolimer, associated with a posterior teeth restorative composite resin (Filtek P60, 3M). The bonding sites were treated according to the instruction of the manufacturers. The 60 teeth, duly embedded and ground, were assigned to four groups with 15 teeth each: group 1, the adhesive was light cured during 10 sec with visible light (Curing Light, 3M) with power density of 410 mW/cm2 and the composite resin was light cured during 20 sec with visible light; group 2, the adhesive and the composite resin were cured during 10 seconds with argon laser with 150 mW of power; group 3, the adhesive and the composite resin were cured during 10 sec with argon laser with 200 mW of power; and group 4, the adhesive and the composite resin were cured during 10 sec with argon laser with 250 mW of power. The composite resin was light cured in layers of 1 mm of thickness until the model of teflon with 3 mm in height was completely filled.
The tensile bond strength test was performed in a Mini-Instron (model 4442) and the results for group 1 were 19.75 MPa (+/-4.65), group 2 were 16.09 MPa (+/-7.27), group 3 were 11.56 MPa (+/-4.50), and group 4 were 11.90 MPa (+/-5.78).
One can conclude that the tensile bond strength promoted by the polymerization with visible light presented greater tensile bond strength than the polymerization with argon laser with 200 mW and 250 mW, but there was no significant difference between visible light and argon laser with 150 mW. There was no significant difference between argon laser with 150 mW and argon laser with 200 mW or 250 mW.
Photomedicine and Laser Surgery 11/2005; 23(5):493-7. · 1.25 Impact Factor
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ABSTRACT: The argon laser is an alternative light source that can be used for the photopolymerization of resin-based dental materials and for tooth bleaching. The argon laser emits specific laser lines with wavelengths that correspond to the absorption peak of camphoroquinone, the initiator of polymerization for the adequate photocuring of resin composite. The collimated beam of the argon laser does not decrease with distance and an optical fiber has access to all cavity areas. In addition, the temperatures produced by an argon laser when curing resin-based materials and performing in-office tooth bleaching are significantly lower than those of conventional photocuring units. Argon is one of the three dental laser wavelengths that have been cleared by the FDA for tooth whitening. This article reviews the literature to examine the role that argon lasers can play in dental treatment.
General dentistry 55(5):416-9.
