树脂粘接法固定牙周松动下前牙的临床观察

[摘要] 目的 观察用4-META/MMA-TBB树脂固定因牙周炎松动下前牙的临床疗效。方法 对56例经过牙周基础治疗,牙周炎得到控制,下前牙松动达Ⅱ°以上的患者,用4-META/MMA-TBB树脂在牙齿邻面直接粘接固定,定期观察2年,记录牙周检查指数并对患牙牙周临床检查效果及粘接固定效果进行评价。结果 4-META/MMA-TBB树脂固定牙周炎所致松动下前牙3、12、24个月后,患牙的牙龈出血指数、探诊深度、附着丧失显著降低(P<0.05);固定2年牙周临床检查有效率为92.9%,粘接固定有效率为89.3%。结论 4-META/MMA-TBB树脂粘接固定牙周炎所致的松动下前牙2年,对患牙牙周状况的改善效果显著且粘接效果稳定。     

树脂直接粘接法固定牙周松动前牙的二年效果观察

目的观察牙周炎松动前牙在用树脂直接粘接法固定治疗后二年的临床效果。方法牙周基础治疗后的12例牙周炎患者共计20颗Ⅱ～Ⅲ度松动前牙，采用4-META／MMA—TBB树脂在牙齿邻面将松牙直接粘接固定，定期观察，2年时对粘接固定治疗效果进行评价。观察粘接有无松脱，惠牙动度、探诊深度、附着丧失及牙槽骨高度的变化，用患者自我评分方法评价咀嚼功能的改善和对美观及舒适度的影响。结果18颗牙在二年中无松脱，20个月时2颗拥挤牙咬硬物后粘接松脱，已行再固定。二年时患牙的探诊深度、附着丧失较固定前有所改善（均值分别减少0．57mm、0．47mm，P〈0．05）；牙槽骨高度占根长的百分比与固定前相比平均增加7．04％（P〈0．05）；咀嚼功能评分从固定前的2．92±1．38分升至8．75±1．22分（P〈0．05），患者对临床美学效果满意，自觉舒适无异物感。结论采用4-META／MMA—TBB树脂直接粘接法固定牙周炎所致松动前牙，具有关观、舒适的特点，二年时粘接效果稳定，牙周状况改善，有助于改善牙齿的咀嚼功能。     

Bonding ability of 4-META self-etching primer used with 4-META/MMA-TBB resin to enamel and dentine: Primary vs permanent teeth

Objectives

The present study compared the efficacies of the self-etching Teeth Primer (TP: 4-META), and the etchants Red Activator (RA; 65% phosphoric acid) and Green Activator (GA; 10% citric acid with 3% ferric chloride), for bonding to enamel and dentine of human primary and permanent teeth, when used with 4-META/MMA-TBB resin (Bondfill SB).

Methods

Forty-eight non-carious primary canines and third molars were used. Eight groups were prepared: Group 1 (primary enamel with RA), Group 2 (permanent enamel with RA), Group 3 (primary enamel with TP), Group 4 (permanent enamel with TP), Group 5 (primary dentine with GA), Group 6 (permanent dentine with GA), Group 7 (primary dentine with TP) and Group 8 (permanent dentine with TP). Micro-tensile bond strengths (MTBS) were measured and analyzed statistically using ANOVAs and Tukey HSD tests at α = 0.05. Efficacy of etching/priming and the morphology of bonded interfaces were observed with SEM.

Results

Etching/priming efficacy of TP on enamel was low. The MTBS of Group 2 was significantly higher than the other groups (Groups 1, 3 and 4). For dentine, significant differences in MTBS were observed, in the order of Groups 6 > 8 > 7 = 5 (p < 0.05). The MTBSs of permanent dentine were significantly higher than primary dentine. For primary teeth, there was no significant difference in the MTBSs between enamel and dentine, irrespective of primer or etchant (p > 0.05).

Conclusion

TP primer/Bondfill SB may be used as an alternative to other adhesive/resin composite systems for bonding to enamel and dentine of primary teeth.     

Effect of the dental adhesive, 4-META/MMA-TBB resin, on adhesion and keratinization of regenerating oral epithelium

Background and Objective:  The 4-META/MMA-TBB [4-(2-methacryloxyethyl)trimellitic anhydride/methyl methacrylate-tributylborane] resin is widely used as a dental adhesive. It has also been applied in the dressing of gingival wound surfaces following periodontal surgery. However, its effect on the regeneration and/or cell attachment of the oral epithelium remains to be clarified. To evaluate the effect of the resin applied as a wound dressing, we investigated expression of laminin 5, integrin β₄ and cytokeratin 14 in regenerating oral epithelium treated with this resin following gingivectomy from the viewpoint of cell attachment and differentiation.
Material and Methods:  The resin was applied to the entire wound surface in rats after gingival surgery, and regenerating epithelium was examined immediately and at 1, 3, 5, 7 and 14 days later. The resin was removed 2 weeks after application in some animals and tissue further examined at 1, 3, 5 and 7 days later.
Results:  Regenerating epithelium under the resin was not keratinized, but became keratinized immediately after removal of the resin. Laminin 5 and integrin β₄ were immunolocalized in the basal lamina, the internal basal lamina, in marginal cells of the regenerating epithelium and at the resin–regenerating epithelium interface. Cytokeratin 14 localized in the regenerating epithelium underneath the resin, as well as in healthy and regenerated junctional epithelial cells.
Conclusion:  These results suggest that this resin covers the wound surface and that the regenerating epithelium biologically adheres to the resin during the initial process of its regeneration.     

Influence of ascorbic acid on bonding of peroxide-affected dentin and 4-META/MMA-TBB resin

The purpose of this study was to evaluate the tensile bond strength (TBS) to peroxide-exposed dentin. Furthermore, the effect of ascorbic acid (AA) on the bond strength of peroxide-exposed dentin was investigated. Extracted bovine dentin was exposed to 10% carbamide peroxide, 30% hydrogen peroxide, or distilled water for 30 min, then treated with 10% AA (0, 30, 90, and 180 min), and conditioned with 10% citric acid/3% ferric chloride. The polymethyl-methacrylate (PMMA) rod was bonded to the treated bovine dentin with 4-META/MMA-TBB resin. A minidumbbell-shaped bonded specimen was prepared from these bonded assemblies and the TBS was tested. The fractured surfaces were also observed with a scanning electron microscope. Exposure to peroxide before bonding significantly reduced bond strength. The application of AA to the peroxide-exposed dentin increased bond strength. On the other hand, an adverse effect of AA was found in distilled water-affected dentin. Extended resin fibers were partially seen in the peroxide-exposed dentin. In conclusion, peroxide reduced the bond strength, and the stronger the oxidation, the weaker the obtained bond. Antioxidation with AA recovered the bond strength, and this effect increased the longer the AA was applied.K. Yazaki was formerly affiliated with Department of Pharmacology, Tokyo Dental College, 1-2-2, Masago, Mihama-ku, Chiba 261-8502, Japan. He is now in private practice.     

Effect of a self-etching primer containing 4-META and sodium sulfite after phosphoric acid etching on bonding strength of MMA-TBB resin to human enamel

Purpose

The aim of this study was to evaluate the shear bond strength and durability of MMA-TBB resin to human enamel applied a self-etching primer with phosphoric acid etching.

Effect of HEMA on bonding of Er:YAG laser-irradiated bovine dentine and 4-META/MMA-TBB resin

The purpose of this study was to evaluate the priming effect of 2-hydroxyethylmetaclirate (HEMA) following acid treatment on resin bonding to prototype Er:YAG laser-irradiated dentine. Extracted bovine dentine following laser irradiation was acid treated by aqueous solution of 10% citric acid (10-0) or 10% citric acid/3% ferric chloride (10-3), and additionally treated with 35% HEMA. Pre-treated dentines were bonded to the polymethyl-methacrylate (PMMA) rod with 4-META/MMA-TBB resin (Super Bond C & B) and miniaturized dumbbell-shaped bonded specimens were prepared. These specimens profiled for tensile bond testing and fractured surfaces were observed by scanning electron microscopy (SEM). Cross-sections of resin-dentine interface were also examined. The HEMA treatment following acid conditioned by 10-3 or 10-0 for both laser-irradiated and non-irradiated dentines was significantly higher than that without HEMA treatment. SEM view of a fractured specimen showed some cohesive failure in cured resin, but almost all of the fractured surface shows boundary failure between the penetrated resin and underlying dentine. A cross-sectional view of the interface showed a very thick hybrid layer between the hybridized dentine and underlying dentine. It was concluded that HEMA treatment following acid conditioning provided a slightly higher bond strength for both the Er:YAG laser-irradiated and non-irradiated dentines. However, the bond strength of Er:YAG laser irradiated dentine was significantly lower than that of the non-irradiated dentine.     

Bonding and debonding characteristics of orthodontic brackets to human enamel using modified 4-META/MMA-TBB resin

The purpose of this study was to evaluate the performance of modified 4-META/MMA-TBB resin for debonding orthodontic brackets to enamel in terms of easy and safe debonding without loss of adequate bracket bond strength. A mixture of α-tricalcium phosphate (α-TCP) and calcium fluoride (CaF₂) (1:1, w/w) was added to the polymer powder of 4-META/MMA-TBB resin. Human enamel was etched with phosphoric acid or treated with self-etching primer, and then the modified resin was applied to the treated enamel for bonding with orthodontic brackets. The shear bond strength was measured before and after the specimens were subjected to 10,000 thermal cycles between 5 °C and 55 °C. Using TCP/CaF₂-modified resins, the shear bond strength decreased significantly after thermal cycling in phosphoric acid etched specimens but did not change significantly after thermal cycling in self-etching primed specimens. Moreover, in the self-etching primed specimens, no significant differences in shear bond strength were detected among the different TCP/CaF₂-modified resins after thermal cycling. Phosphoric acid etched specimens showed enamel fracture upon debonding of orthodontic bracket. On the contrary, no enamel fracture was recognized in self-etching primed specimens. The addition of TCP/CaF₂ tended to be associated with more residual resin on the tooth surface after debonding, which suggests a lower risk of enamel fracture. TCP/CaF₂-modified resin used with self-etching primer appears to allow easy and safe debonding of orthodontic brackets without loss of adequate bracket bond strength.     

Resin bonding to Er : YAG laser-irradiated dentin: combined effects of pre-treatments with citric acid and glutaraldehyde

The purpose of this study was to evaluate the combined effects of citric acid and glutaraldehyde (GA) on the resin bonding to Er: YAG laser-irradiated dentin. Bovine dentin was prepared with 180- to 600-grit SiC paper and then uniformly irradiated with an Er: YAG laser (laser-irradiated group) or immersed in water at 60 degrees C for 15 min (heated group). The samples were then acid-conditioned with 10% citric acid (10-0) or 10% citric acid/3% ferric chloride (10-3) for 15 s and treated with GA for 10 min before bonding to an acrylic rod with 4-META/MMA-TBB resin. These samples were trimmed to prepare miniaturized dumbbell-shaped specimens. After storage in water at 37C for 1 d, the tensile bond strength was measured, and the fractured surface was evaluated using a scanning electron microscope (SEM). In the laser-irradiated and heated groups, the 10-3+GA-treated specimen had higher bond strength than that of 10-0+GA. On the other hand, the tensile bond strength of 10-3 +GA in the non-irradiated group was lower that that of 10-0+GA. In conclusion, the combination of 10-3 and GA for bonding with 4-META/MMA-TBB resin was the most effective for Er: YAG laser-irradiated dentin and heated dentin, but it was not effective for the non-irradiated dentin.     

Adhesion of 4-META/MMA-TBB resin to heated dentin: effects of pre-treatments with FeCl3 and/or HEMA

The purpose of this study was to compare the tensile bond strengths (TBSs) and failure mode of 4-META/MMA-TBB resin to 60 degrees C-heated and unheated bovine dentin, especially to investigate the influence of ferric chloride contained in citric acid pre-conditioning. In addition, the effect of HEMA priming for heated dentin was also evaluated. The TBSs to heated dentin were significantly lower than those to unheated dentin. Adhesive failures were observed in most specimens of the heated and HEMA-non primed group. HEMA application to heated dentin significantly increased the TBSs in each acid conditioning, which were also significantly higher than those of the unheated and ferric chloride-contained citric acid-conditioned group. It was clarified that heating dentin decreased the bond strength without HEMA priming even if the dentin surfaces were acid conditioned with 10-3, while HEMA priming after acid conditioning recovered the bond strength.     

2种材料嵌体用于后牙Ⅱ类洞修复的临床效果比较

目的: 比较CAD/CAM全瓷嵌体与Ceramage 聚合瓷嵌体修复活髓后牙Ⅱ类洞的临床效果。方法: 选取牙体缺损活髓后牙需制备Ⅱ类洞的患者97例,共100颗患牙。随机分为2组,分别制作CAD/CAM全瓷嵌体与Ceramage 聚合瓷嵌体修复。比较2组修复后12个月、24个月的效果,参照改良美国公共卫生服务评价体系（USPHS）,评价术后牙敏感、修复体折裂、修复体脱落、边缘着色情况。采用SPSS13.0软件包对2种材料嵌体修复12个月、24个月的计数资料进行X²检验,等级资料进行Wilcoxon秩和检验。结果: 12个月时,2组病例均修改成功,结果无显著差异（P>0.05）。24个月时,术后牙敏感、修复体脱落例数,2组比较无显著差异（P>0.05）;修复体折裂发生例数,聚合瓷组低于全瓷组（P<0.05);边缘着色发生例数,聚合瓷组高于全瓷组（P<0.05）。结论: 聚合瓷嵌体修复活髓后牙Ⅱ类洞术后抗折裂力高于CAD/ CAM 全瓷嵌体,缺点是边缘着色发生率较高,应根据患者的需求选择合适的修复方案。     

Adhesion of 4-META/MMA-TBB resin to enamel treated with EDTA metal ammonium solutions. Effect of Fe.NH4, Co.NH4 and Cu.NH4 salts

EDTA 3-2 (Fe.NH4), EDTA 3-2 (Co.NH4) and EDTA 3-2 (Cu.NH4) at pH 7.4 were investigated to determine effective pretreatment to promote strong adhesion of 4-META/MMA-TBB resin to enamel with minimum demineralization. EDTA 5-0 (NH4) solution which does not contain a metal salt was also investigated as a control. The amount of Ca2+ demineralized during the pretreatment and the tensile bond strength to enamel were measured. The pretreated enamel surface and the resin surface of the adhesion junction were observed with SEM. When the enamel surface was pretreated with EDTA 3-2 (Fe.NH4) for 60 seconds, the tensile bond strength of the resin to enamel was 7.1 MPa after the thermal cycling test. No direct correlation was observed between the amount of Ca2+ demineralized and the tensile bond strength. The stable and strong bonding to enamel was taken place without strong mechanical retention.     

Efficacy of using self-etching primer with a 4-META/MMA-TBB resin cement in bonding orthodontic brackets to human enamel and effect of saliva contamination on shear bond strength

The objective of this study was (1) to evaluate the effectiveness of Megabond when used with Superbond C&B, a 4-methacryloloxyethyl trimellitate anhydride (4-META)/methyl methacrylate (MMA)-tri-n-butyl borane (TBB) resin, to bond orthodontic metal brackets to human enamel and (2) to examine the influence of saliva contamination on shear bond strength. Metal brackets were bonded to phosphoric acid-etched or Megabond-treated human premolars using Superbond C&B resin cement. The effects of saliva contamination after acid etching or self-etch priming, and the effect of re-etching or self-etch priming after saliva contamination on shear bond strength were also assessed. The shear bond strengths were measured after immersion in water at 37 degrees C for 24 hours. Data were analyzed using two-way analysis of variance and Fisher's protected least significant difference test for multiple comparisons. There were no significant differences in shear bond strength between phosphoric acid etching and self-etch priming for no contamination, saliva contamination, and repeat treatment (etching or priming) after saliva contamination. With phosphoric acid etching, saliva contamination significantly decreased the shear bond strength. Repeat phosphoric acid etching after saliva contamination did not significantly improve the bond strengths. With self-etching primer treatment, however, saliva contamination did not cause any decrease of bond strength. Phosphoric acid etching produced more enamel fracture than self-etching primer treatment. Field-emission scanning microscopy revealed less dissolution of enamel surface resulted from self-etching primer compared with phosphoric acid. These results suggest that Megabond when used with Superbond C&B resin cement may be a good candidate for bonding orthodontic brackets to human enamel.     

Durability of bonding between 4-META/MMA-TBB resin to dentin pretreated with 10-3. The effect of 10-3 pretreating period and subsequent glutaraldehyde treatment

Adhesion durability between dentin pretreated with 10-3 and 4-META/MMA-TBB resin was studied. Reduction of etching periods with 10-3 was not so effective as expected. The weakening of bond strength during immersion in water at 37 degrees C to the dentin pretreated for 1 sec occurred faster than those for either 5 sec or 10 sec. The strength decreased from 12 MPa at 1 day to 9 MPa at 3 months, 3 MPa at 6 months and finally 2 MPa at 1 year in the case of 1 sec pretreated dentin. On the other hand, the strength became half after the storage in water for 1 year in the cases of 5 and 10 sec pretreated dentins. Combination of 10-3 pretreatment and subsequent glutaraldehyde treatment could stabilize the decrease but not completely. SEM and TEM examinations suggested that dentinal collagen exposed by the etching but not entangled and impregnated by poly (4-META-co-MMA) easily deteriorated by water during the longer immersion. Collagen modified with 10-3 and then with glutaraldehyde was also changed by the longer immersion.