Nd:YAG laser ablation and acid resistance of enamel

The acid resistance of Nd:YAG laser-ablated enamel surfaces was studied by evaluating crystal structure, mineral distribution, and fluorescence radiance and image in the present study. For comparison, 37% phosphoric acid etching was performed. The formation of beta-tricalcium phosphate (beta-TCP) was confirmed in the laser-ablated surface. The Ca/P ratio increased after ablation due to mineral re-distribution. In contrast, the Ca/P ratio decreased after acid etching due to mineral loss. The laser-ablated enamels showed a smaller increase of fluorescence radiances and less clear laser confocal scanning microscope images than those observed in the acid-etched enamels. The former suggests a minimized mineral loss. The Nd:YAG laser irradiation will enhance the acid resistance and retard the carious progression in enamel.     

Effectiveness of an Er:YAG laser in etching the enamel surface for orthodontic bracket retention

The purpose of this study was to test the effectiveness of an Er:YAG laser in etching the enamel surface for orthodontic treatment. Bovine incisors were either acid-etched or laser-treated. An orthodontic bracket was attached on each treated surface using one-step dentin adhesive and self-curing resin. Tensile bond strength was then evaluated. In addition, the surface morphology of specimens treated with phosphoric acid/laser and self-etching primer, as well as the cross-section of enamel-primer-resin interfaces, were observed. One-Up Bond F-treated specimens after Er:YAG laser ablation showed statistically similar tensile bond strength (9.9 +/- 1.3 MPa) to that of phosphoric acid-etched specimens (11.8 +/- 1.7 MPa). Surface roughness and thickness of the enamel-primer-resin interfaces did not much affect the tensile bond strength of the tested specimens. In conclusion, Er:YAG laser ablation achieved clinically acceptable level of tensile bond strength when used with One-Up Bond F.     

Resin bond strength and micromorphology of human teeth prepared with an Erbium:YAG laser

PURPOSE: To evaluate the in vitro effect of the Er:YAG laser and high-speed rotary instrumentation on the bond strength of resin composite to human enamel and dentin, and determine which conditioner, either phosphoric acid or a self-etching primer, resulted in higher bond strengths with either of the surface treatments. METHODS: 48 third molars were used. Dentin and enamel specimens were sectioned and polished with 600-grit SiC paper and treated either with carbide bur or an Erbium:YAG laser and treated with one of three different conditions, acid-etch/bonding agent (Scotchbond Multi-Purpose Plus), no etching and same bonding agent, and an experimental self-etching primer (EXL 547). After storage for 48 hours at 37 degrees C and 100% humidity, specimens were prepared in an hourglass shape for microtensile bond test (ca. 1 mm2) and debonded in tension. Areas were measured and bond strengths were calculated for each specimen. Failure modes, micromorphology of surface treatments and bonding interfaces of representative specimens from acid-etched and self-etched groups were analyzed with scanning electron microscopy. Means were compared using three-way analysis of variance, and Scheffé post-hoc test (P < 0.05) was used to determine differences among surface treatments, tooth substrate and conditioners. RESULTS: Dentin prepared with the carbide bur and treated with phosphoric acid followed by the application of Scotchbond Multi-Purpose had the highest bond strengths (35.7 MPa). Enamel and dentin prepared with the Er:YAG laser had the highest bond strengths when the surfaces were acid-etched followed by Scotchbond Multi-Purpose (25.8-21.1 MPa). Carbide bur exhibited higher bond strengths than laser with the use of the experimental self-etching primer but laser showed higher bond strengths than the bur with the use of Scotchbond Multi-Purpose and no etching. The predominant failure mode of most of the treatment conditions was partially adhesive between the bonding resin and enamel or dentin, and partially cohesive within the bonding resin. SEM analysis revealed the absence of a smear layer on laser-treated teeth when compared to untreated control and bur-cut teeth.     

Nd:YAG laser ablation of enamel for orthodontic use: tensile bond strength and surface modification

To test the feasibility of Nd:YAG laser ablation for orthodontic use, bovine enamels were ablated at 2.5 and 3.5 W/pulse conditions. Orthodontic brackets were attached on the ablated enamel surface using a self-curing resin. For comparison, a 37% phosphoric acid solution was used to etch the enamel surface. The strength to detach the brackets was estimated for both surface treatments. Modifications of the enamel surfaces were also compared using a scanning electron microscope for both treatments. The tensile bond strengths from the laser-ablated enamels were significantly lower than that from the phosphoric acid-etched enamels. The higher laser power treatment gave a significantly higher bond strength average than with the lower laser power. The laser-ablated surfaces showed the formation of craters. The formation involved melting and solidification of enamel. Each crater had numerous micropores. Microscopically, the ablated surface was smooth, while much of the acid-etched surface contained numerous microspaces.     

Differences in bonding to acid-etched or Er:YAG-laser-treated enamel and dentin surfaces

STATEMENT OF PROBLEM: Er:YAG (erbium-doped yttrium aluminium garnet) lasers have been effective in the removal of dental tissues. It has been suggested that they are also useful for preparing dental surfaces for adhesion, but results to date have been controversial. PURPOSE: This study compared the tensile strength of bracket-tooth bonds obtained after preparation of the surface for adhesion (dentin or enamel) by conventional acid-etching or by Er:YAG laser etching and investigated microstructure of resin-tooth interfaces using the 2 procedures. MATERIAL AND METHODS: Eighty healthy human premolars were used. Brackets were cemented to acid-etched enamel, laser-etched enamel, acid-etched dentin, or laser-etched dentin (20 teeth per group). Dentin was previously exposed using a high-speed handpiece. Acid-etching was with 37% orthophosphoric acid (15 seconds for enamel, 5 seconds for dentin). Laser etching was with Er:YAG laser (four 200 mJ pulses per second for enamel; four 160 mJ pulses per second for dentin). Brackets were bonded with autocuring resin paste, having first applied a primer (dentin only) and then light-cured bonding resin. Tensile strength was determined with a universal testing machine. Data were analyzed with 2-way ANOVA and subsequent t test with Bonferroni correction. Fracture patterns were compared by the Wilcoxon test with Bonferroni correction. For SEM studies of the resin-tooth interface, a total of 12 premolars were used (3 for each tissue per treatment combination). RESULTS: Mean tensile bond strength for acid-etched enamel (14.05 +/- 5.03 MPa) was significantly higher (P<.05) than for laser-etched enamel (8.45 +/- 3.07 MPa), and significantly higher (P<.05) for acid-etched dentin (4.70 +/- 2.50 MPa) than laser-etched dentin (2.48 +/- 1.94 MPa). Bond failure after laser etching was due to microcohesive fracture of tooth tissue. SEM studies of both resin-enamel and resin-dentin interfaces indicated extensive subsurface fissuring after laser etching. CONCLUSION: Adhesion to dental hard tissues after Er:YAG laser etching is inferior to that obtained after conventional acid etching. Enamel and dentin surfaces prepared by Er:YAG laser etching show extensive subsurface fissuring that is unfavorable to adhesion.     

Er:YAG激光和酸蚀作用于牙釉质表面后剪切强度的比较研究

目的 探讨Er:YAG激光照射对牙釉质表面的蚀刻效果,并与酸蚀效果进行比较研究.方法 2010年4-7月在山西医科大学选取40颗完整的人离体双尖牙,随机分为4组(每组各10颗牙),即酸蚀组(35%的磷酸),Er:YAG激光组(5Hz,100 mJ,0.5W),酸蚀加Er:YAG激光组,Er:YAG激光加酸蚀组.分别在牙...     

Bond strengths of orthodontic bracket after acid-etched, Er:YAG laser-irradiated and combined treatment on enamel surface

Laser ablation has been proposed as an alternative method to acid etching: however, previous studies have obtained contrasting results. The purpose of this study was to compare the bond strengths after acid etching, laser ablation, acid etching followed by laser ablation, and laser ablation followed by acid etching. Forty specimens were randomly assigned to one of the four groups. Two more specimens in each group did not undergo bond test and were prepared for observation with scanning electron microscope (SEM) after the four kinds of surface treatment. After the bond test, all specimens were inspected under the digital stereomicroscope and SEM to record the bond failure mode. Student's t-test results showed that the mean bond strength (13.0 +/- 2.4 N) of the laser group was not significantly different from that of the acid-etched group (11.8 +/- 1.8 N) (P > .05). However, this strength was significantly higher than that of the acid-etched then laser-ablated group (10.4 +/- 1.4 N) or that of the laser-ablated then acid-etched group (9.1 +/- 1.8 N). The failure modes occurred predominantly at the bracket-resin interface. Er:YAG laser ablation consumed less time compared with the acid-etching technique. Therefore, Er:YAG laser ablation can be an alternative tool to conventional acid etching.     

Microleakage at sealant/enamel interface of primary teeth: effect of Er:YAG laser ablation of pits and fissures

PURPOSE: The objective of this study was to assess microleakage at sealant/enamel interface after treatment of primary teeth occlusal surfaces with 3 etching techniques. METHODS: Thirty sound primary molars were randomly assigned to 3 groups (N = 10): (1) group I = acid etching for 30 seconds; (2) group II = Er:YAG laser (120 mJ; 4 Hz) plus acid-etching; and (3) group III = Er:YAG laser (120 mJ; 4 Hz). Pits and fissures were sealed with a resin-based sealant (Fluroshield, Dentsply/Caulk). Teeth were isolated, thermocycled, immersed in a 0.2% rhodamine B solution for 24 hours, and serially sectioned. Cuts were analyzed for leakage using an optical microscope connected to a video camera. The images were digitized, and a specific software (Axion Vision) assessed microleakage quantitatively (millimeters). The sealant extension on buccal/lingual cusp heights was measured separately, and the percentage of dye penetration along enamel/sealant interface, in relation to the sealant extension, was calculated. Means of dye penetration were: (1) group I = 2%(+/- 3.75); (2) group II = 2%(+/- 3.38); and (3) group III = 4%(+/- 6.26). Data were submitted to ANOVA and Tukey test. RESULTS: A statistically significant difference (P < .05) was observed between the nonetched lased specimens (group III) and those in the other groups. No significant difference (P >.05) was found between the acid-etched and lased/acid-etched groups (I and II). Fissures prepared with Er:YAG laser alone showed the highest degree of microleakage. All specimens exhibted some degree of leakage. CONCLUSIONS: Laser irradiation did not eliminate the need for acid etching enamel prior to the placement of a pit-and-fissure sealant. The ablation of pits and fissures with an Er:YAG laser device did not yield significantly better marginal sealing at primary enamel/sealant interface, compared to conventional acid etching.     

Tensile bond strength and SEM analysis of enamel etched with Er:YAG laser and phosphoric acid: a comparative study in vitro

Er:YAG laser has been studied as a potential tool for restorative dentistry due to its ability to selectively remove oral hard tissue with minimal or no thermal damage to the surrounding tissues. The purpose of this study was to evaluate in vitro the tensile bond strength (TBS) of an adhesive/composite resin system to human enamel surfaces treated with 37% phosphoric acid, Er:YAG laser (lambda=2.94 mum) with a total energy of 16 J (80 mJ/pulse, 2Hz, 200 pulses, 250 ms pulse width), and Er:YAG laser followed by phosphoric acid etching. Analysis of the treated surfaces was performed by scanning electron microscopy (SEM) to assess morphological differences among the groups. TBS means (in MPa) were as follows: Er:YAG laser + acid (11.7 MPa) > acid (8.2 MPa) > Er:YAG laser (6.1 MPa), with the group treated with laser+acid being significantly from the other groups (p=0.0006 and p= 0.00019, respectively). The groups treated with acid alone and laser alone were significantly different from each other (p=0.0003). The SEM analysis revealed morphological changes that corroborate the TBS results, suggesting that the differences in TBS means among the groups are related to the different etching patterns produced by each type of surface treatment. The findings of this study indicate that the association between Er:YAG laser and phosphoric acid can be used as a valuable resource to increase bond strength to laser-prepared enamel.     

In vitro acid resistance of CO2 and Nd-YAG laser-treated human tooth enamel

The purposes of this study were to test the effectiveness of laser treatment (pulsed CO(2) and pulsed Nd-YAG) on in vitro acid resistance of human enamel. Thirty enamel surfaces were prepared from 10 extracted permanent premolars (3 surfaces per tooth). Two experimental surfaces on each tooth were irradiated with either CO(2) or Nd-YAG lasers. All specimens were demineralized in 10 ml lactate buffer for 24 or 72 h after laser treatment. After 24-hour acid treatment the mean concentration of calcium that dissolved into the lactate buffer in the CO(2) laser group was significantly less than in the control group, while the dissolved calcium concentration in the Nd-YAG laser group did not differ from the control group (p > 0.05). The erosion depth in the CO(2) laser group was significantly shallower than in the Nd-YAG laser group (p < 0.001). After 72-hour acid treatment, the acid resistances of neither group of laser-treated surfaces differed significantly from the controls. By scanning electron microscopy, the acid-eroded laser-treated enamel surfaces had type I and type II etching patterns, fissures, and disordered rough surfaces compared to control enamel, with a regular type II etching pattern. CO(2) laser-treated tooth enamel was more resistant to acid challenge than was Nd-YAG laser-treated enamel, given the same fluence, but neither type of laser increased acid resistance of subsurface enamel.     

Shear bond strength and SEM evaluation of composite bonded to Er:YAG laser-prepared dentin and enamel.

OBJECTIVES: The purpose of this study was to evaluate dentin and enamel bond strength to resin composite following high-speed rotary or Er:YAG laser preparation using a total etch adhesive system. The microstructure of resin-tooth interfaces was also investigated. METHODS: Human dentin and enamel specimens were prepared with a high-speed handpiece (KaVo) or Er:YAG laser (DELight) at manufacturer's recommended settings and etched with either 37% H(3)PO(4), laser etched, or not etched. Composite rods (Z-250, 3M/ESPE) were bonded to specimens with an adhesive (Adper Scotchbond Multi-Purpose, 3M/ESPE). After thermocycling, specimens were tested in shear to failure. RESULTS: Two-factor ANOVA detected significant differences in the main effects of preparation and etch type, and interaction (p<0.001). Post hoc analyses showed that in both dentin and enamel, only the acid-etched specimens had significantly higher mean bond strengths, with rotary-prepared specimens having significantly higher mean bond strengths versus laser prepared specimens. Within each preparation type, in both dentin and enamel, acid etch was better than laser etch, and laser etch was better than no etch. Scanning electron microscopy of laser-ablated specimens demonstrated significant surface scaling and subsurface fissuring beyond normal resin penetration depth. SIGNIFICANCE: Adhesion to laser-ablated or laser-etched dentin and enamel was inferior to that of conventional rotary preparation and acid etching.     

Effect of Er:YAG laser irradiation on acid resistance to bovine dentin in vitro

Resin bond strength to Er:YAG laser irradiated dentin has been reported to be lower than that of unlased dentin. The reasons have been much discussed, but not clarified. One hypothetical cause has been discussed that lased dentin is acid resistant, therefore, the etching effect of acid conditions decreases. The purpose of this study was to evaluate the acid resistance of laser-irradiated dentin and compare it with the dissolved mineral of Er:YAG laser irradiated dentin and unlased dentin. This experiment was a pilot study to assess the etching effect of pre-conditioner for resin bonding to lased dentin. Bovine dentin was irradiated by Er:YAG laser and immersed in 0.1 M lactic buffer solution (pH 4.0). The dissolved Ca and P in the solution were then both measured. Dissolved Ca from lased dentin was not significantly different from that coming from unlased dentin (p > 0.05). The molar ratio of Ca/P did not differ significantly between lased and unlased dentin, either (p > 0.05). Under FE-SEM view before immersion, the dentin surface was covered with a smear layer in unlased dentin, but this layer was not clearly observed in lased dentin. These results suggested that the lased dentin had little or no resistance to lactic buffer solution.     

Effect of enamel preparation method on in vitro marginal microleakage of a flowable composite used as pit and fissure sealant

OBJECTIVES: The aim of this in vitro study was to evaluate the microleakage in occlusal surfaces, after preparation with Er:YAG laser and compared to the diamond-bur conventional technique. METHODS: Thirty premolars were divided into three groups: I - high-speed handpiece + 37% phosphoric acid; II - Er:YAG laser (350 mJ, 4 Hz and 112 J/cm(2)) + 37% phosphoric acid; and III - Er:YAG laser (350 mJ, 4 Hz and 112 J/cm(2)) + Er:YAG laser (80 mJ, 4 Hz, and 25 mJ/cm(2)). All cavities received the same adhesive system and were restored with flowable composite according to manufacturer's instructions. Teeth were submitted to thermal cycling and immersed in 50% silver nitrate solutions for 8 h in total darkness. Specimens were sectioned longitudinally in the bucco-lingual direction, in slices of 1 mm thick. Each slice was immersed into photo developing solution and was photographed, and microleakage was scored from 0 to 7, by three calibrated examiners. RESULTS: A statistically significant difference (P < 0.0001) was observed between Er:YAG laser prepared and etched specimens and those in the other groups. CONCLUSIONS: It can be concluded that no significant difference was noted between the two types of enamel preparation when etching was performed. Preparing and treating the enamel surface exclusively by Er:YAG laser resulted in the highest degree of leakage.     

Spectroscopic characterization of enamel surfaces irradiated with Er:YAG laser

The purpose of this study was to investigate the effect of laser irradiation on the enamel surface spectroscopically. Polished bovine enamel surface was irradiated with an Er:YAG laser apparatus and chemically analyzed using X-ray photoelectron spectroscopy (XPS). XPS detected core electron peaks such as carbon (C 1s) and nitrogen (N 1s), as well as calcium (Ca 2s, Ca 2p, Ca 3s, Ca 3p), phosphorous (P 2s, P 2p), and oxygen (O 1s), from the control enamel surface. After irradiation, XPS revealed that the intensity of C 1s peak slightly decreased while that of N 1s diminished below the detection limit. Detailed C 1s narrow scan spectrum of the Er:YAG laser-irradiated enamel surface showed that C-O/C-N, C = O/-CON=, -COO-, and CO,3(2-) components, attributed to the specific composition of enamel and any common carbon contamination in surplus, relatively decreased. The binding energies of Ca 2p and P 2p, delta (Ca 2p, P 2p), and the Ca/P ratio of lased enamel were found to be different from those of non-lased enamel. It was also shown that Er:YAG laser ablation caused surface alterations to the apatitic inorganic components of tooth tissue.     

Er:YAG激光照射后釉质结构和成分变化的研究

目的:观察Er:YAG激光不同能量和照射时间对釉质表面形态和成分的影响。方法:处理后的104个釉质样本随机抽取8个为C组(空白对照组),剩余部分随机分为A(照射10 s)和B(照射20 s)两大实验组,其中每一大组再随机分为6个小组,分别用Er:YAG激光以1～6 W不同能量进行照射。照射后体视显微镜测量A、B两组凹坑的直径和深度,能量色散型X射线荧光光谱(EDX)测定3组的Ca、P含量和其比值的变化。结果:1～6 W不同能量照射20 s(B组)的凹坑直径和深度均明显大于照射10 s(A组)各能量组,差异均有统计学意义(P<0.05);A、B两组实验组的Ca、P含量均明显高于空白对照组,差异有统计学意义(P<0.05);空白组和两实验组的Ca/P比值差均无统计学差异(P>0.05)。结论:在Er:YAG激光一定能量的照射下,釉质的结构和成分均会产生一定的变化。     

Influence of Er:YAG laser irradiation distance on the bond strength of a restorative system to enamel

OBJECTIVES: The aim of the present study was to investigate in vitro the effect of Er:YAG laser on bonding to enamel, varying the irradiation distance. METHOD: Tensile bond strength of an adhesive restorative system to non-irradiated and irradiated enamel surfaces was evaluated. Thirty caries-free human third molars were sectioned in mesio-distal direction and embedded in acrylic resin. Enamel was flattened, and a 3-mm-diameter bonding area was demarcated. Specimens were randomly assigned into six groups: groups I-V were treated with the Er:YAG laser (80 mJ/2 Hz), varying the irradiation distance (11, 12 mm-focused, 14, 16 and 17 mm, respectively), followed by 35% phosphoric acid etching. Control group (VI) received treatment with phosphoric acid alone. Single Bond adhesive system was applied on the conditioned enamel, and composite resin cones, bonded to enamel, were fabricated with Z250. After storage, samples were tested in tensile to failure (50 kgf and 0.5 mm/min). RESULTS: Means in MPa were: I-9.67 (+/-3.44); II-13.29 (+/-2.65); III-13.33 (+/-2.22); IV-14.87 (+/-3.58); V-16.43 (+/-4.52); VI-22.90 (+/-3.03). ANOVA and Tukey test revealed statistically significant decrease of bond strength in group I (P < 0.05). Groups II-IV presented similar results, as did groups IV and V. Control group (VI) yielded the best overall performance (P < 0.05). CONCLUSION: Er:YAG laser irradiation adversely affected adhesion to enamel. However, bond strength was influenced by the irradiation distance, thus being stronger with the increase of distance to the target tissue.     

Evaluation of the enamel etching capacity of six contemporary self-etching adhesives

OBJECTIVES: The purpose of this study was to evaluate the capacity of six contemporary self-etch primers/adhesives to demineralize ground enamel by means of ultrastructural analysis of the etching surface under SEM and by spectroscopic measurement of the percentage of calcium and phosphate ions dissolved. METHODS: Seventy non-carious extracted human third molars were sub-divided into 2 groups of 35 teeth each. The teeth of the first group were ground to expose flat, polished enamel surfaces 3-4mm thick. The samples thus obtained were treated with six self-etch bonding systems and a phosphoric acid gel (control group). The self-etch priming agent was then eliminated and the etched enamel surface observed by SEM. From the teeth of the second group, disc-shaped specimens were made from ground enamel and subjected to application of each of the six self-etchants. Once the etching product had been rinsed off, the rinse solution was analyzed by atomic flame spectroscopy to evaluate the percentage of calcium and phosphate ions dissolved. RESULTS: SEM images show that AdheSE, Adper Prompt L-Pop and Xeno III, despite having a less intensive etching efficacy than phosphoric acid, gave a regular pattern over a considerable surface area and depth. iBond and One-Up Bond F gave less regular demineralization. For Clearfil SE Bond, the demineralization was ineffective. Results of the percentage of mineral loss show that Adper Prompt L-Pop and Xeno III were the most efficient self-etch products. AdheSE, iBond and One-Up Bond F, respectively exhibited decreasing demineralizing capacity. Clearfil SE Bond, however, gave low proportions of calcium and phosphate ions loss and was considered unsatisfactory. CONCLUSION: The action on enamel was not the same for all self-etch systems tested. The etching potential of the self-etch adhesives was lower than that of phosphoric acid but some self-etch systems, particularly those with monomers containing phosphate derivatives, gave results close to those obtained with phosphoric acid.     

不同能量Er,Cr∶YSGG激光照射对牙体硬组织抗酸作用的体外研究

目的:探讨Er,Cr∶ YSGG激光照射能量与牙体硬组织抗酸性之间的关系.方法:采用2.5、3.5、5W激光照射牙釉质样本,2、3、4W激光照射牙本质样本.经0.1 mmol/L乳酸液浸泡24 h后检测钙磷溶出量,能谱仪检测样本表面钙磷原子百分比,SEM观察表面形态.结果:除2.5W牙釉质组,其余牙釉质和牙本质实验组钙磷溶出量显著低于对照组(P＜0.05),实验组间无明显差异.激光照射后牙釉质钙磷比增加,牙本质钙磷含量均无变化.SEM观察显示实验组样本表面粗糙,釉柱间隙增大,牙本质小管口周牙本管突出成袖口状.结论:一定能量的Er,Cr∶YSGG激光照射可使牙硬组织抗酸性提高.     

Er, Cr: YSGG激光照射后牙体硬组织抗酸性变化的研究

目的 对Er，Cr：YSGG激光照射后牙体硬组织人工龋蚀的抗酸性变化进行体外研究，为其临床应用提供有价值的理论依据。方法 牙釉质标本采用6W，牙本质标本采用4W Er，Cr：YSGG激光照射6s，0．1mol／L乳酸脱矿，原子吸收分光光度计检测脱矿液中溶解的钙离子浓度，能谱分析仪进行原子含量分析，扫描电镜观察牙体硬组织表面结构变化。结果 Er，Cr：YSGG激光照射后牙釉质和牙本质的钙离子溶出浓度均显著低于对照组，钙含量在牙釉质和牙本质均显著高于对照组，磷含量在牙釉质和牙本质标本中都增高，但仅在牙釉质组差异有统计学意义，钙／磷重量比差异均无统计学意义。激光照射后釉质表面不平呈鳞片状，无玷污层，釉质结构清晰可见；牙本质小管开放，无熔融及碳化。结论 Er，Cr：YSGG激光照射后牙体硬组织抗酸性增强，而且激光照射不对牙体硬组织造成热损伤。     

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目的评价Er:YAG激光照射对牙本质与瓷块间粘接强度的影响。方法选取2010年9月至2011年9月山西医科大学口腔医院颌面外科因正畸拔除的完整无龋坏、无隐裂的前磨牙30颗,分别制备3mm×3mm的牙本质面,随机分为以下3组:Er:YAG激光组、酸蚀组、酸蚀+Er:YAG激光组,每组10个样本。通过扫描电镜观察各组样本的表面形态,并检测牙本质与瓷块间的粘接强度。结果酸蚀+Er:YAG激光组粘接强度值最高,与酸蚀组和Er:YAG激光组相比较,差异有统计学意义(P<0.01),而酸蚀组与Er:YAG激光组间差异无统计学意义(P>0.05)。结论酸蚀联合Er:YAG激光照射能够增强牙本质与瓷块间的粘接强度,是牙体组织粘接前有效的表面处理方式。