Influence of the coronal restoration on the outcome of endodontically treated teeth

Abstract

Objective: The tooth weakens due to removal of hard tissue during an endodontic procedure. Many dentists find it difficult to choose between different coronal restorations after root canal treatment (RCT). Studies show that the coronal restoration may affect the endodontic prognosis. This student-based study had three aims. (1) Examine the choice of coronal restoration of endodontically treated teeth at a Scandinavian dental school, (2) examine the survival of these restorations and (3) evaluate the influence of the coronal restoration on the outcome of the RCT.

Material and methods: Radiographic and clinical examination was performed on 127 posterior teeth. The quality of the root canal treatment and the periapical status (PAI-index) were evaluated.

Results: 43.8% of the teeth were restored with an indirect coronal restoration and 47.2% with a direct coronal restoration. The period from finished root canal treatment until placement of a permanent coronal restoration was significantly longer for an indirect restoration than a direct restoration. The teeth treated with a PAI score of 1 and 2 following pulpectomy, necrotic pulp treatment and endodontic retreatment was 93.8%, 82.6% and 69.4%, respectively.

Conclusion: There was no significant association between choice of coronal restoration and PAI-score.     

根管充填质量和牙冠修复对根尖周健康的影响

目的:探讨根管充填质量和牙冠修复对根尖周组织健康的影响。方法:选择126个根管充填≥2年的牙齿作为研究对象,通过临床检查、X线影像和PAI指数,分析根管充填质量、牙冠修复情况与根尖周组织健康之间的关系。结果:根管充填密合的牙齿根尖周组织健康状况明显优于根管充填不密合的牙齿(P<0.05),而不同牙冠修复方式对根管充填牙齿的根尖周组织健康状况没有影响。结论:根管充填密合度影响根尖周组织健康。     

暂时封固对根管治疗牙冠方微渗漏影响的体外研究

目的 评价不同暂封材料、暂封方式对根管治疗牙冠方微渗漏的影响,探讨根管治疗牙冠方微渗漏发生情况及与时间的关系.方法 收集离体牙,常规根管治疗后随机分组,2%亚甲基蓝染色,制作透明样本,体视显微镜下观察样本微渗漏情况,根据染料渗漏最大长度评分,收集数据并进行统计分析.结果 暂封1、4 周时,Cavit-G和Caviton微渗漏评分低于氧化锌丁香酚水门汀(ZOE);暂封2 周,Caviton微渗漏评分低于ZOE和Cavit-G.ZOE作为暂封材料,两种方式样本微渗漏评分比较差异无统计学意义(P > 0.05);暂封1 周时,Cavit-G和Caviton直接与间接暂封微渗漏评分差异无统计学意义(P > 0.05),暂封2周,Cavit-G和Caviton微渗漏评分差异无统计学意义(P > 0.05).随暂封时间的延长,3种材料的微渗漏差异有统计学意义(P < 0.05).结论 Caviton冠方暂封效果最好,其次为Cavit-G,ZOE最差;间接暂封明显加速Cavit-G和Caviton暂封样本冠方微渗漏;Caviton和 Cavit-G用于暂封的适宜时间为2周,ZOE为1周.     

根管内屏障对根管治疗牙冠方微渗漏影响的体外研究

完整单根管前磨牙42颗,截去牙冠,常规根管治疗,随机分为4组,2%亚甲基蓝染色,2周后取出,制作透明样本,体视显微镜观察并测量样本微渗漏长度,并对数据进行统计学分析。结果显示阴性对照组未见染料渗入根管,阳性对照组见整个根管被染色(单因素方差分析,P<0.001),微渗漏长度的均数和置信区间由GP(4.80±0.54,4.42～5.19)、ZPC(3.39±0.65,2.92～3.85)、Filtek Z350(2.07±0.27,1.87～2.27)至Fiju VⅡ(1.68±0.15和1.57～1.79)呈递减趋势,两两比较,除Filtek Z350与F ijuVII间差异无统计学意义外(P>0.05),其余各组间差异均有统计学意义(P<0.05)。说明根管内屏障能够提高根管治疗牙冠方封闭能力;Filtek Z350、Fuji VⅡ可作为根管内屏障材料应用于临床。     

Influence of coronal restorations on the periapical health of endodontically treated teeth

Abstract – The purpose of the study was to evaluate a possible relationship between the quality of the coronal restoration, the root canal obturation and the periapical status of endodontically treated teeth. Full mouth series of radiographs from randomly selected patient charts at the Dental Faculty, University of Oslo were examined. A total of 1001 endodontically treated teeth restored with a permanent restoration were evaluated independently by two examiners. According to a predetermined set of radiographic criteria, the technical quality of the root filling of each tooth was scored as either good (GE) or poor (PE), and the technical quality of the coronal restoration was scored as good (GR) or poor (PR). The root and the surrounding structures were then evaluated and according to the periradicular findings, the treatment was categorized as success or failure. The success rate for all endodontically treated teeth was 67.4% ( n =1001). Teeth with root canal posts had a success rate of 70.7% ( n =527) and teeth without posts had a success rate of 63.6% ( n =472). The two groups with technically good endodontics had the highest success rates. In combination with technically good restorations the success rate was 81% (GE+GR, 81%) and combined with technically poor restorations the success rate was 71% (GE+PR, 71%). The two groups with technically poor endodontics combined with either good restorations or poor restorations had significantly lower success rates (PE+GR, 56% and PE+PR, 57%). The technical quality of the endodontic treatment as judged radiographically was significantly more important than the technical quality of the coronal restoration when the periapical status of endodontically treated teeth was evaluated.     

Influence of coronal restorations on the periapical health of endodontically treated teeth

The purpose of the study was to evaluate a possible relationship between the quality of the coronal restoration, the root canal obturation and the periapical status of endodontically treated teeth. Full mouth series of radiographs from randomly selected patient charts at the Dental Faculty, University of Oslo were examined. A total of 1001 endodontically treated teeth restored with a permanent restoration were evaluated independently by two examiners. According to a predetermined set of radiographic criteria, the technical quality of the root filling of each tooth was scored as either good (GE) or poor (PE), and the technical quality of the coronal restoration was scored as good (GR) or poor (PR). The root and the surrounding structures were then evaluated and according to the periradicular findings, the treatment was categorized as success or failure. The success rate for all endodontically treated teeth was 67.4% (n = 1001). Teeth with root canal posts had a success rate of 70.7% (n = 527) and teeth without posts had a success rate of 63.6% (n = 472). The two groups with technically good endodontics had the highest success rates. In combination with technically good restorations the success rate was 81% (GE + GR, 81%) and combined with technically poor restorations the success rate was 71% (GE + PR, 71%). The two groups with technically poor endodontics combined with either good restorations or poor restorations had significantly lower success rates (PE + GR, 56% and PE + PR, 57%). The technical quality of the endodontic treatment as judged radiographically was significantly more important than the technical quality of the coronal restoration when the periapical status of endodontically treated teeth was evaluated.     

Adhesive restoration of anterior endodontically treated teeth: influence of post length on fracture strength

Objectives

This study aims to evaluate the fracture resistance of endodontically treated anterior teeth restored with crowns made of composite or ceramic and retained without the use of a post (endocrowns) or with posts of 5 mm (short) and 10 mm in length (long).

Material and methods

Forty-eight intact maxillary incisors were selected for the study. After endodontic treatment, the crowns were sectioned 2 mm coronally to the cementoenamel junction provided with a ferrule of 2 mm. The roots were randomly divided into six groups (n?=?8) according to the post length and type of coronary restoration. The crowns were fabricated with the chairside economical restoration of esthetic ceramics system. Group 1 was restored with a 10-mm glass fiber post, composite core, and a full-coverage ceramic crown (LPCer); group 2, with a 5-mm glass fiber post, composite core, and a full-coverage ceramic crown (SPCer); group 3, with a 10-mm glass fiber post, composite core, and a full-coverage composite crown (LPCpr); group 4, with a 5-mm glass fiber post, composite core, and a full-coverage composite crown (SPCpr); and groups 5 (EndoCer) and 6 (EndoCpr) were restored with ceramic and composite endocrowns, respectively. The teeth were then thermomechanically loaded in a chewing machine. After fatigue, the specimens were loaded to fracture. Data were analyzed with ANOVA and chi-square test. Mode of failure was defined as repairable or non-repairable.

Results

Presence of post, post length, and crown material had no significant effect on the fracture resistance. Groups restored with endocrowns presented a higher number of repairable fractures in respect to the other groups.

Conclusions

Presence of a post had no effect on the restorations’ fracture strength.

Clinical relevance

Although this in vitro study has some limitations in respect to its clinical relevance, the restoration of largely destroyed anterior teeth with the use of an endocrown or a short glass fiber post might have advantages over a large glass fiber post.     

The restoration of endodontically treated teeth. Part 3. Cores

The functions and features of cores in restorative dentistry and the importance of preserving sound tooth tissue are discussed. The experimental and clinical support for a perceived superiority of cast post cores is reviewed. It is suggested that there is a need to re-evaluate this viewpoint, particularly when restoring posterior teeth. The materials currently in use are briefly discussed as well as research relating to possible core/luting agent interactions.     

The restoration of endodontically treated teeth. Part 2. Posts

Posts are normally used to aid core retention and to provide tooth support, although a significant minority question the use of posts in the latter role. A direct relationship is thought to exist between the quantity of sound tooth structure and tooth strength and care is required when preparing teeth to accept posts. Post configuration is of over-riding importance in determining retention and support and the effect on retention of small increases to post length should not be over emphasized. Because accurate post fit is important to maximize both retention and support, direct fabrication techniques using matched post/reamer systems are recommended.     

Guidelines for using posts in the restoration of endodontically treated teeth

A review of the literature was done to determine when posts are required for restoring endodontically treated teeth and to give guidance on preparation of post space, design of posts, and use of luting agents. Posts were deemed to be unnecessary when adequate coronal tooth structure was present to retain a core. It was found that tooth structure should not be removed to construct a stronger post. The thinnest post with adequate strength was recommended. For best retention, it was found that post surfaces should not be smooth. When resin reinforced glass ionomer cements were used, they were found to be potentially harmful to restored teeth. Remaining coronal tooth structure was found to have the highest correlation in regard to success of the final restoration of endodontically treated teeth.     

Are posts mandatory for the restoration of endodontically treated teeth?

Abstract— In this era of fiscal and professional accountability, variations in the utilization of posts to improve the retention of crowns or other restorations on endodontically treated teeth are no longer acceptable. This practice ignores not only the potential for root perforations during post space preparations, but also the adhesive properties of modem resin-based materials. Since the retention of restorations hinges on many other factors, the placement of posts does not necessarily assure service quality and may even lead to deleterious changes. The need to reappraise the utilization of posts in the restoration of endodontically treated teeth cannot be overstated.     

Periapical status of endodontically treated teeth in relation to the technical quality of the root filling and the coronal restoration

The purpose of this study was to evaluate the relationship of the quaality of the coronal restoration and of the rot canal obturation on the radiographic periapical status of endodontically treated teeth. Full-mouth radiographs from randomly selected new patient folders at Temple University Dental School were examined. The first 1010 endodontically treated teeth restored with a permanent rstoration were evaluated independtly by two examiners. Post and core type restorations were excluded. According to a predetermined radiographic standard set of criteria, the technical quality of the root filling of each tooth was scored as either good (GE) or poor (PE), and the quality of the coronal restoration similarly good (GR) or poor (PR). The apical one-third of the root and surrounding structures were then evaluated radigraphically and the periradicular status categorized as (a) absence of periradicular inflammation (API) or (b) presence of periradicular inflammation (PPI). The rate of API for all endodontically treated teeth was 61.07%, GR resulted in significantly more API cases than GE, 80%, versus 75.7%. PR resulted in significantly more PPI cases than PE, 30.2% versus 48.6%. The combination of GR and GE had the highest API rate of 91.4%, significantly higher than PR and PE with a API rate of 18.1%.     

Crown placement increases long-term survival of endodontically treated teeth

J Evid Base Dent Pract 2002;2:273-4     

Assessment of coronal microleakage of three materials used in endodontically treated teeth

This study compared the coronal microleakage of three restorative materials used to seal the access cavity in root treated teeth. Thirty six teeth were prepared and three experimental groups were obturated and the access cavity filled with different materials; Group A--Intermediate Restorative Material, Group B--Fuji II and Group C--Dyract AP. Microleakage was assessed by Indian ink penetration. The mean coronal dye leakage for Group A was 0.895 mm, for Group B 1.914 mm and for Group C 3.245 mm. There was significantly (p < 0.05) more dye leakage in teeth restored with Dyract AP compared to those with Fuji II or IRM.