A temporary space maintainer using acrylic resin teeth and a composite resin.

A one-session technique for preparing a temporary space maintainer has been described. The technique consists of attaching an acrylic resin pontic to etched surfaces of natural adjacent teeth by means of a composite resin. The main advantages of this technique are elimination of premature tooth preparation, good esthetics, fair strength, low cost, and rapid completion of the restoration without the need of a dental laboratory.     

Effect of surface treatments on the bond strength between composite resin and acrylic resin denture teeth

PURPOSE: This investigation studied the effects of 3 surface treatments on the shear bond strength of a light-activated composite resin bonded to acrylic resin denture teeth. MATERIALS AND METHODS: The occlusal surfaces of 30 acrylic resin denture teeth were ground flat with up to 400-grit silicon carbide paper. Three different surface treatments were evaluated: (1) the flat ground surfaces were primed with methyl methacrylate (MMA) monomer for 180 seconds; (2) light-cured adhesive resin was applied and light polymerized according to the manufacturer's instructions; and (3) treatment 1 followed by treatment 2. The composite resin was packed on the prepared surfaces using a split mold. The interface between tooth and composite was loaded at a cross-head speed of 0.5 mm/min until failure. RESULTS: Analysis of variance indicated significant differences between the surface treatments. Results of mean comparisons using Tukey's test showed that significantly higher shear bond strengths were developed by bonding composite resin to the surfaces that were previously treated with MMA and then with the bonding agent when compared to the other treatments. CONCLUSION: Combined surface treatment of MMA monomer followed by application of light-cured adhesive resin provided the highest shear bond strength between composite resin and acrylic resin denture teeth.     

Direct composite resin restorations in posterior teeth

Direct adhesive composite resin restorations are being used extensively. A proper understanding of the technique and its indications has contributed to the widespread use of this restorative approach. Recent industrial developments brought novel technologies to dentistry including the introduction of nanofillers to the restorative procedures. This article reviews some features of this new type of composite resin, discusses its advantages over other materials, and presents an application technique for restoration of posterior teeth through a clinical case report.     

Pin-retained composite resin cores for posterior teeth

Two techniques for the fabrication of pin-retained composite resin cores for posterior teeth have been described.The advantage of using a composite resin in place of amalgam as a core material is that the restoration can be completed in a single appointment rather than the two appointments required when amalgam is used.A disadvantage of the use of the composite resins as core material is the difficulty in identifying the demarcation line between the resin and tooth structure. This lack of definition presents the possibility of placing the finish line of the final preparation on the resin rather than on sound tooth structure. Application of a Dycal demarcation bead or use of the ultraviolet light-activated resin offers a solution to this problem.     

Laser-induced fluorescence to discriminate between a dental composite resin and tooth.

PURPOSE: Investigation of laser-induced fluorescence of an experimental pigment (Flu) to discriminate between a filling and the tooth and its influence on the material properties of experimental dental composites. MATERIALS AND METHODS: Three experimental composites (EC) were manufactured. The standard contained no Flu, Flu-0.5 contained 0.5%, Flu-1.0 contained 1%. To judge the extent of fluorescence, specimens and fillings placed in natural teeth were irradiated with an infrared laser (980 nm, 120 mW). Flexural strength, modulus of elasticity, depth of cure, water sorption, solubility, and color (CIE-L(*)a(*)b(*)-values) were measured to investigate the influence of Flu on EC. ANOVA was calculated and the statistical significance was p < 0.05. RESULTS: Strong laser-induced green fluorescence was observed so that fillings and tooth structures were clearly discriminated. No influence of Flu on flexural strength and modulus of elasticity occurred. Water sorption and solubility were far below the limits of EN ISO 4049. Increasing Flu concentrations revealed minor but significant reduction of depth of cure, shifts to more white and red and less yellow. SIGNIFICANCE: Flu provides laser-induced fluorescence allowing an easy discrimination between fillings and teeth. Flu did not severely influence the material properties.     

Reconstruction and recovery of hemisectioned teeth using direct fiber-reinforced composite resin: case report

An increased wish by patients to maintain their dentition and recent advances in dentistry have led to the treatment and preservation of teeth that once would have been removed. Consequently, hemisections, root amputations, and bisections are procedures frequently used. The prognosis of endodontically treated teeth depends on the type of reconstruction as well as the success of the endodontic treatment. Along with technological improvements in adhesive resins, cements, and composite restoratives, the evolution of fiber-reinforced posts enables the rehabilitation of endodontically treated teeth with greater esthetics and virtually no predisposition to root fracture. The purpose of this report was to describe the endodontic, surgical, and restorative treatments of a mandibular first molar with an endodontically and periodontally diseased mesial root, for functional, orthodontic, and aesthetic reasons. This case report shows that the clinical application of fiber-reinforced composite resins in hemisectioned teeth may be a treatment choice for highly damaged teeth with endodontic and/or periodontal lesions. It also emphasizes the advantages of the elimination of orthodontic and prosthetic treatment needs by different treatment strategies, especially in adolescent patients.     

Dyract与光固化复合树脂修复楔状缺损的比较

目的 比较Dyract复合体与光固化复合树脂修复楔状缺损的效果.方法　对150例648颗楔状缺损牙分成两组,一组用Dyract复合体修复348颗牙,一组用光固化复合树脂修复300颗牙.结果 经过1～2年的追踪观察,Dyract组成功率达93%,复合树脂组成功率为76%,两组有显著性差异(P<0.05).结论Dyract复合体粘结性强,对牙髓刺激性小,是修复楔状缺损较为理想的材料.     

An amalgam and composite resin splint for posterior teeth

A combined amalgam and composite resin splint was constructed for a 35-year-old man with pathologic tooth mobility. This type of stabilization was selected because of the poor prognosis, economic considerations, and poor alignment of the teeth. Amalgam restorations were inserted with strong contacts. Composite resin material was used to fill the channel cut through all amalgam restorations and reinforced with braided stainless steel wire. The poor alignment of the teeth would have caused other types of splints to fail.     

Reinforced composite resin foundations for endodontically treated teeth

An endodontically treated tooth having a healthy periodontium can contribute long service to the oral apparatus. A reinforced composite resin dowel and core provides the needed reinforcement to combat the effects of occlusal stresses. This allows an endodontically treated tooth to serve the patient as a normal tooth.     

Gap formation between different cavity walls and resin composite systems on primary and permanent teeth

AIM: The aim of this study was to compare the effectiveness of five self-etching and etch-rinse dentin-bonding agents in achieving a gap-free adaptation between the restorative material and the dentin in primary and permanent teeth. METHODS AND MATERIALS: Gaps located at the restoration dentin interface were evaluated using scanning electron microscopy (SEM). RESULTS: There were more gaps on the corner of the cavities, but no significant difference was detected between different cavity walls (p>0,05). Statistical results of the SEM analysis revealed fewer gaps in the restorations made with self-etching dentin bonding agents than etch-rinse agents at the restoration-dentin interface in both primary and permanent teeth. CONCLUSION: Self-etching bonding systems were preferable in primary and permanent teeth according to the results of this study. However, further studies should be conducted to determine a favorable strategy to eliminate the gaps on the corners of cavities and maintain a gap-free adaptation between resin composite and tooth structure.     

Grandio纳米树脂与可乐丽树脂充填治疗后牙深龋的疗效比较

目的 对比Grandio纳米树脂与可乐丽树脂充填治疗后牙深龋的临床效果.方法 选择后牙深龋患者276例398颗,随机分为2组.试验组138例197颗患牙使用Grandio纳米树脂充填,对照组138例201颗患牙使用可乐丽树脂充填.术后随访2年,对比两组充填体解剖形态、固位、边缘密合度及牙齿继发龋、牙髓、根尖周及牙周状况.结果 治疗后6个月试验组和对照组成功率分别为97.46％和97.01％,成功率差异无统计学意义(x2=0.074,P=0.786).治疗后2年试验组和对照组成功率分别为95.43％和88.06％,差异有统计学意义(x2 =7.110,P=0.008),其中Ⅰ类洞成功率差异无统计学意义,Ⅱ类洞成功率试验组高于对照组,差异有统计学意义(x2=8.728,P=0.003).结论 Grandio纳米树脂充填治疗后牙深龋Ⅱ类洞远期疗效较佳.