Endodontic working length measurements of premolars and molars in high-resolution dental MRI: a clinical pilot study for assessment of reliability and accuracy.

OBJECTIVES: To prospectively assess the reliability and accuracy of high-resolution, dental MRI (dMRI) for endodontic working length (WL) measurements of premolars and molars under clinical conditions. MATERIALS AND METHODS: Three-Tesla dMRI was performed in 9 subjects who also had undergone cone-beam computed tomography (CBCT) (mean age: 47 ± 13.5 years). A total of 34 root canals from 12 molars (4/8, upper/lower jaw; 22 root canals) and 11 premolars (2/9 upper/lower jaw; 12 root canals) were included. CBCT and dMRI datasets were reconstructed to visualize the root canal in one single slice. Subsequently, two radiologists measured the root canal lengths in both modalities twice in blinded fashion. Reliability and accuracy for both modalities were assessed using intraclass correlation coefficients (ICCs) and Bland-Altman analysis, respectively. RESULTS: Reliability (intra-rater I/II; inter-rater) of dental MRI measurements was excellent and comparable to CBCT for premolars (0.993/0.900; 0.958 vs. 0.993/0.956; 0.951) and for molars (0.978/0.995; 0.986 vs. 0.992/0.996; 0.989). Bland-Altman analysis revealed a mean underestimation/bias (95% confidence interval) of dMRI measurements of 0.8 (- 1.44/3.05) mm for premolars and 0.4 (- 1.55/2.39) mm for molars. In up to 59% of the cases, the accuracy of dMRI for WL measurements was within the underestimation margin of 0 to 2 mm short of the apical foramen AF. CONCLUSIONS: In vivo demonstration and measurement of WL are feasible using dMRI. The reliability of measurements is high and equivalent to CBCT. Nonetheless, due to lower spatial resolution and longer acquisition time, the accuracy of dMRI is inferior to CBCT, impeding its current use for clinical treatment planning. CLINICAL RELEVANCE: dMRI is a promising radiation-free imaging technique. Its reliability for endodontic working length measurements is high, but its accuracy is not satisfactory enough yet.

In vitro evaluation of different dental materials used for the treatment of extensive cervical root defects using human periodontal cells.

INTRODUCTION: Repair materials for extensive cervical root defects may come in direct contact with periodontal tissues. This in vitro study compared the effects of four calcium silicate cements (CSC), one resin-modified glass ionomer cement, and one glass carbomer cement on primary human gingival fibroblasts (HGF), alveolar osteoblasts (HAO), and a human osteoblast cell line (hFOB 1.19). METHODS: HGF, HAO, and hFOB were seeded on discoid test specimens. Relative numbers of viable cells were quantitatively assessed after 1 and 24 h for cytotoxicity/adhesion assays and after 4, 24, 48, and 72 h for proliferation assays. Data were statistically analyzed using non-parametric tests (α = 0.05). RESULTS: Relative to the control (100 %), CSC allowed for mean numbers of 71-81 % viable HGF and 80-82 % viable HAO. Then, 64 % of HGF and 56 % of HAO were assessed on GC Fuji II LC. Mean numbers of viable cells were 59-64 % HGF and 67-68 % HAO for GCP Glass Fill specimens. Cells exposed to CSC over 24 h remained viable and even increased in number. Both cell types adhered almost equally well to CSC and GC Fuji II LC. GCP Glass Fill continued to decrease cell viability and adhesion. CSC-based materials and GC Fuji II LC allowed for HGF and hFOB proliferation; however, none of the tested materials specifically stimulated cell proliferation. CONCLUSIONS: CSC characterized by low cytotoxicity. GC Fuji II LC shows moderate cytotoxic effects. ProRoot MTA, Harvard MTA, Biodentine, EndoSequence putty, and GC Fuji II LC allow HGF and HAO to adhere and HGF and hFOB to proliferate. GCP Glass Fill decreases cell viability, adhesion, and proliferation. CLINICAL RELEVANCE: CSC remain the paramount biologic choice for the repair of extensive cervical root defects. GC Fuji II LC might be considered in addition to CSC when the defect comprises supracrestal areas and the restoration requires superior aesthetic and mechanical characteristics.

Sweets consumption of preschool children--extent, context, and consumption patterns.

OBJECTIVES: Sweets consumption is one of the risk factors of caries, especially among children. The aim of our study was to explore the extent and context of preschoolers' sweets consumption and to identify high-risk groups. MATERIALS AND METHODS: The baseline cross-sectional data used originated from a nutritional intervention study encompassing 879 parental surveys, which were obtained in 52 kindergartens in Baden-Württemberg-the third largest federal state in Germany-between September and March 2009. Our outcome variable "sweets consumption" was operationalized using food-frequency items and analyzed by testing the influence of sociodemographic, educational, cultural, and family context covariates. RESULTS: Most preschoolers consumed sweets every day-on average 9.7 ± 6.2 times per week. Most popular were cookies, gummy bears, and chocolate. Sweets consumption did not correlate significantly with sociodemographic factors like age and sex but rather was associated with cultural and contextual factors such as immigrant background, parental education, specific nutritional knowledge levels, and access arrangements in the home. CONCLUSIONS: The consumption patterns identified are a result of high availability and parental influence (factors such as parents' knowledge levels, interest in, and habits regarding their child's nutrition). CLINICAL RELEVANCE: Dental practitioners should place more emphasis on gathering information from young patients regarding excessive and frequent consumption of sweets and consequently on trying to educate the children and their parents on oral health risks associated with such consumption. Particular attention is to be paid to children of Turkish and Arabic decent, as they have been shown to consume above-average amounts of sweets.

Outcome after Partial Pulpotomy: Long-term Results of the Prospective Clinical MMP-9 Study.

PURPOSE: While the objective of partial pulpotomy is to preserve the vitality and function of the pulp tissue, the preopera-tive pulp status is the main prognostic factor for its success. To date, however, there is little data on long-term success rates. Therefore, the aim of this prospective pilot study was to assess the long-term outcome of partial pulpotomy in per-manent teeth after carious pulp exposure without signs or symptoms of irreversible pulpitis, verified clinically, radio-graphically, and via MMP-9 levels. MATERIALS AND METHODS: Patients in whom permanent teeth with extremely deep carious lesions were diagnosed as com-pletely asymptomatic (n = 8) or with signs of reversible pulpitis (n = 10) underwent non-selective caries removal followed by a blood test to assess the level of MMP-9. The teeth were thereafter partially pulpotomised, MTA-capped, and immedi-ately restored with composite resin. Follow-up examinations were performed by endodontically experienced examiners focusing on clinical and radiographic assessment. RESULTS: One patient could not be contacted and was lost to follow-up. Overall, the follow-up period ranged from 2-8 years (mean = 4.4 years). The majority of teeth remained functional and without pathology; one tooth was classified as having failed because of a vertical root fracture. There was no statistically significant difference in the groups' success rate (p = 0.3). The estimated overall survival rate was 94.1% (95% CI: 0.84-1.00) after 4 years according to the Kaplan-Meier method. CONCLUSION: Pulp vitality in permanent teeth can be preserved with high success rates by means of partial pulpotomy after carious pulp exposure in asymptomatic teeth or in teeth with reversible pulpitis.

MTA Matrix Technique: Restoration of Teeth with Deep Subgingival Defects Extending Down to the Osseous Crest.

PURPOSE: To present a new restorative technique for the restoration of teeth with deep subgingival hard tissue defects extending down to the osseous crest without additional surgical or orthodontic interventions by combining mineral trioxide aggregate (MTA) and composite material. MATERIALS AND METHODS: The MTA matrix technique starts by deeply inserting a metal matrix as far down to the bone level as possible. The matrix should then be fixated with a matrix holder in its end position. If the matrix band does not seal tightly in the deepest area of the cavity, small portions of MTA are carefully applied to the lower end of the inner side of the matrix band. The MTA acts as a barrier for fluid control. Additional haemostasis is not necessary. Subsequently, the tooth is restored with an etch-and-rinse adhesive and composite resin. The clinical effects were observed in a case series of three patients over a period of 3 to 4.5 years. RESULTS: Excellent outcomes were observed clinically and radiologically. Teeth restored with the MTA matrix technique showed no failures due to the materials used or due to secondary caries or periodontal inflammation after an observation period of 3 to 4.5 years. Probing depths ranged from 2 to 4 mm without bleeding on probing, including the subgingivally restored areas. CONCLUSION: Although only a few casuistic observations are available to date, by using the MTA matrix technique, successful restoration of teeth with subgingival defects down to the alveolar bone crest seems possible without the need of additional surgical or orthodontic measures. Further clinical studies are necessary to confirm the feasibility of this technique.

Reliability and accuracy of dental MRI for measuring root canal length of incisors and canines: a clinical pilot study.

To evaluate whether high-resolution, non-contrast-enhanced dental MRI (dMRI) can reliably and accurately measure the canal length of incisors and canines compared with cone-beam computed tomography (CBCT). Three-Tesla dMRI was performed in 31 participants (mean age: 50.1 ± 14.2 years) with CBCT data. In total, 67 teeth were included (28 from the upper jaw and 39 from the lower jaw; 25 central incisors, 22 lateral incisors, and 20 canines). CBCT and dMRI datasets were reconstructed to visualize the root canal pathway in a single slice in the vestibulo-oral (V-O) and mesio-distal (M-D) direction. Root canal length was measured twice by two radiologists using dMRI and CBCT. Data were statistically analyzed by calculating intraclass correlation coefficients (ICCs) and performing Bland-Altman analysis. The reliability of dMRI measurements was excellent and comparable to that of CBCT measurements (intra-rater I/intra-rater II/inter-rater was 0.990/0.965/0.951 for dMRI vs. 0.990/0.994/0.992 for CBCT in the M-D direction and 0.991/0.956/0.967 for dMRI vs. 0.998/0.994/0.996 for CBCT in the V-O direction). According to Bland-Altman analysis, the mean (95% confidence interval) underestimation of root canal lengths was 0.67 mm (- 1.22 to 2.57) for dMRI and 0.87 mm (- 0.29 to 2.04) for CBCT in the M-D direction/V-O direction. In 92.5% of cases, dMRI measurements of canal length had an accuracy within 0-2 mm. Visualization and measurement of canal length in vivo using dMRI is feasible. The reliability of dMRI measurements was high and comparable to that of CBCT measurements. However, the spatial and temporal resolution of dMRI is lower than that of CBCT, which means dMRI measurements are less accurate than CBCT measurements. This means dMRI is currently unsuitable for measuring canal length in clinical practice.

High-Resolution Single Tooth MRI With an Inductively Coupled Intraoral Coil-Can MRI Compete With CBCT?

OBJECTIVES: The aims of this study were to quantify T1/T2-relaxation times of the dental pulp, develop a realistic tooth model, and compare image quality between cone-beam computed tomography (CBCT) and high-resolution magnetic resonance imaging (MRI) of single teeth using a wireless inductively coupled intraoral coil. METHODS: T1/T2-relaxometry was performed at 3 T in 10 healthy volunteers (283 teeth) to determine relaxation times of healthy dental pulp and develop a realistic tooth model using extracted human teeth. Eight MRI sequences (DESS, CISS, TrueFISP, FLASH, SPACE, TSE, MSVAT-SPACE, and UTE) were optimized for clinically applicable high-resolution imaging of the dental pulp. In model, image quality of all sequences was assessed quantitatively (contrast-to-noise ratio) and qualitatively (visibility of anatomical structures and extent of susceptibility artifacts using a 5-point scoring scale). Cone-beam computed tomography served as the reference modality for qualitative assessment. Statistical analysis was performed using 2-way analysis of variance, Fisher exact test, and Cohen κ. RESULTS: In vivo, relaxometry of dental pulps revealed T1/T2 relaxation times at 3 T of 738 ± 100/171 ± 36 milliseconds. For all sequences, an isotropic resolution of (0.21 mm) 3 was achieved, with acquisition times ranging from 6:19 to 8:02 minutes. In model, the highest contrast-to-noise ratio values were observed for UTE, followed by TSE and CISS. The best image/artifact quality, however, was found for DESS (mean ± SD: 1.3 ± 0.3/2.2 ± 0.0), FLASH (1.5 ± 0.3/2.4 ± 0.1), and CISS (1.5 ± 0.4/2.5 ± 0.1), at a level comparable to CBCT (1.2 ± 0.3/2.1 ± 0.1). CONCLUSIONS: Optimized MRI protocols using an intraoral coil at 3 T can achieve an image quality comparable to reference modality CBCT within clinically applicable acquisition times. Overall, DESS revealed the best results, followed by FLASH and CISS.

Fiber-reinforced composite fixed dental prostheses: a retrospective clinical examination.

PURPOSE: To obtain survival data on 32 fiber-reinforced fixed dental prostheses which were inserted in our department and to rate the quality of these restorations on the basis of esthetic, biological, and functional parameters. MATERIALS AND METHODS: Thirty-two patients with fiber-reinforced fixed dental prostheses were included in the study. The fiber frameworks were made of a polymer-monomer-preimpregnated continuous unidirectional glass fiber material. The survival times, failure events, and clinical parameters were recorded. Restorations in function without previous failure were classified as "Overall Survival". The classification "Functional Survival" was assigned in the event of minor failure and subsequent repair. Loss of the restoration was regarded as "Failure". The quality rating was performed using modified USHPS/Ryge criteria. RESULTS: The follow-up interval ranged from 2 to 64 months with a median follow-up time of 18.2 months. Twenty-four restorations were classified as "Overall Survival", seven were classified as "Functional Survival", and one was classified as "Failure". The overall survival at the median follow-up time was 74.4%. For the majority, the quality rating (USHPS/Ryge criteria) yielded clinically excellent results in all categories. No restoration was rated as insufficient or poor. CONCLUSION: Fiber-reinforced composite fixed dental prostheses provide sufficient stability and very good esthetic, biological, and functional performance in the case of specific clinical indications.

Assessment of different dyes used in leakage studies.

The goal of this in vitro study was to identify the most suitable dye for endodontic dye leakage studies, which could be a further step towards standardisation. The root canals of 70 extracted, single-rooted human adult teeth were enlarged to apical size 50 using hand instruments. The teeth were divided into seven groups (n = 10 each), and all root canals were completely filled by injection with one of the following dyes: methylene blue 0.5% and 5%, blue ink, black ink, eosin 5%, basic fuchsin 0.5% and drawing ink. Transverse root sections from the coronal, middle and apical part of the roots were examined, and the percentage of the dentine penetrated by dye was evaluated by software-supported light microscopy. In addition, the range of particle size of drawing ink particles was evaluated. There were conspicuous differences in the relative dye penetration into the root dentine and the penetration behaviour in the different root sections (two-way ANOVA, both p < 0.0001). One dye (drawing ink) penetrated less into the root dentine compared with all the others (p <0.0001). The particle size of this agent (0.1-2 microm) corresponds best with the size range of a representative selection of 21 species of pathogenic endodontic bacteria. Compared to the other dyes tested, drawing ink appears to be superior for use in endodontic dye leakage studies. The penetration behaviour into the root dentine of all the other dyes tested might be one factor that limits the applicability of these dyes in dye leakage studies.

Preservation of a Split Tooth: Nonsurgical Clinical Management.

A tooth is considered to be a split tooth if it contains a fracture line extending from the occlusal surface through both marginal ridges. Currently, the only treatment option for a split tooth is extraction. The present case report describes a novel therapeutic strategy for the preservation of a split tooth (first maxillary premolar) with a fracture in the mesiodistal direction. A systematic nonsurgical procedure involving visualization and slight widening of the fracture line is described. This procedure facilitates sealing of the fracture gap with a biocompatible calcium silicate cement (mineral trioxide aggregate) as well as internal composite resin stabilization and cuspal coverage restoration of the tooth. A 3-year follow-up showed a promising clinical and radiographic outcome. The concept presented here is an alternative treatment option for a split tooth, which allows preservation of the tooth rather than its extraction.

Differentiation of periapical granulomas and cysts by using dental MRI: a pilot study.

The purpose of this pilot study was to evaluate whether periapical granulomas can be differentiated from periapical cysts in vivo by using dental magnetic resonance imaging (MRI). Prior to apicoectomy, 11 patients with radiographically confirmed periapical lesions underwent dental MRI, including fat-saturated T2-weighted (T2wFS) images, non-contrast-enhanced T1-weighted images with and without fat saturation (T1w/T1wFS), and contrast-enhanced fat-saturated T1-weighted (T1wFS+C) images. Two independent observers performed structured image analysis of MRI datasets twice. A total of 15 diagnostic MRI criteria were evaluated, and histopathological results (6 granulomas and 5 cysts) were compared with MRI characteristics. Statistical analysis was performed using intraclass correlation coefficient (ICC), Cohen's kappa (κ), Mann-Whitney U-test and Fisher's exact test. Lesion identification and consecutive structured image analysis was possible on T2wFS and T1wFS+C MRI images. A high reproducibility was shown for MRI measurements of the maximum lesion diameter (intraobserver ICC = 0.996/0.998; interobserver ICC = 0.997), for the "peripheral rim" thickness (intraobserver ICC = 0.988/0.984; interobserver ICC = 0.970), and for all non-quantitative MRI criteria (intraobserver-κ = 0.990/0.995; interobserver-κ = 0.988). In accordance with histopathological results, six MRI criteria allowed for a clear differentiation between cysts and granulomas: (1) outer margin of lesion, (2) texture of "peripheral rim" in T1wFS+C, (3) texture of "lesion center" in T2wFS, (4) surrounding tissue involvement in T2wFS, (5) surrounding tissue involvement in T1wFS+C and (6) maximum "peripheral rim" thickness (all: P < 0.05). In conclusion, this pilot study indicates that radiation-free dental MRI enables a reliable differentiation between periapical cysts and granulomas in vivo. Thus, MRI may substantially improve treatment strategies and help to avoid unnecessary surgery in apical periodontitis.

In vitro leakage associated with three root-filling techniques in large and extremely large root canals.

This study assessed the apical leakage of ultrasonically condensed root fillings in extremely large canals, compared to cold lateral condensation and thermoplastic compaction. Ninety single-rooted teeth were used. In 45 teeth canals were enlarged to size 70 (large). The remaining 45 canals were enlarged to size 140 (extremely large). Each set of teeth was subdivided into three root-filling groups (n = 15): (1) cold lateral condensation (LC); (2) thermoplastic compaction (TC); and (3) ultrasonic lateral condensation (UC). Teeth in all six subgroups were subjected to drawing ink penetration, cleared, and evaluated for linear apical dye leakage. Significantly deeper dye penetration (p < 0.04, Wilcoxon rank-sum test) was observed for LC than for UC. TC did not differ significantly from LC and UC. Dye penetration was significantly deeper (p < 0.0001) in canals enlarged to size 140 than to size 70, independent of root-filling method. Apical leakage associated with ultrasonically condensed root fillings was less than that with cold lateral condensation. It was consistently greater in extremely large canals than that in large ones.

A Prospective Clinical Pilot Study on the Level of Matrix Metalloproteinase-9 in Dental Pulpal Blood as a Marker for the State of Inflammation in the Pulp Tissue.

INTRODUCTION: Differentiation between reversible pulpitis (savable pulp) and irreversible inflammation of the pulp tissue (nonsavable pulp) based only on clinical and radiographic diagnoses has proven to be difficult. Pulp exposure allows for the collection of pulpal blood to quantitatively determine the level of inflammation markers or proteolytic enzymes, even with small samples. Pulpitis is associated with the invasion of neutrophil granulocytes and their release of matrix metalloproteinase-9 (MMP-9). METHODS: Forty-four patients (aged 18-74 years, mean = 35 years), each with 1 tooth with carious pulp exposure presenting with different stages of pulpitis, were included in this prospective, 2-center clinical study; 26 patients presented with irreversible pulpitis (groups 3 and 4), 10 with reversible pulpitis (group 2), and 8 with completely asymptomatic teeth with deep carious lesions (group 1). Six of the 26 patients with teeth diagnosed with irreversible pulpitis had not taken any nonsteroidal anti-inflammatory drugs and were evaluated as a separate group (group 4). Partial pulpotomy and blood sample collection from the pulp chamber were performed. The total levels of MMP-9 and tissue inhibitor of metalloproteinase-1 were assessed by fluorometric and colorimetric enzyme-linked immunosorbent assays, respectively. The Mann-Whitney U test and Spearman rank correlations were used to compare the MMP-9 levels with different stages of pulpal inflammation; significance was set at .05. RESULTS: The MMP-9 levels in the asymptomatic teeth (group 1) were significantly different from those in the teeth with reversible pulpitis (group 2, P = .006) or irreversible pulpitis (group 4, P < .001). A statistically significant difference was also observed between the MMP-9 levels in group 1 and group 3 (P < .001) in which the patients had taken nonsteroidal anti-inflammatory drugs. CONCLUSIONS: These findings indicate that the MMP-9 levels in pulpal blood samples could be a useful ancillary diagnostic tool for distinguishing different stages of pulp tissue inflammation.

Outcome of orthograde retreatment after failed apicoectomy: use of a mineral trioxide aggregate apical plug.

INTRODUCTION: This controlled, single-center historic cohort study project evaluates treatment outcomes of a nonsurgical treatment approach after failed apicoectomy. METHODS: The treatment outcomes of nonsurgical retreatment after a failed apicoectomy were evaluated clinically and radiographically. The study cohort consisted of teeth that had received primary root canal treatment and subsequent apicoectomy elsewhere before the patients presented with post-treatment disease. Orthograde retreatment and obturation using an apical mineral trioxide aggregate plug was performed by postgraduate students and endodontic specialists in 25 cases between 2004 and 2012. Pre-, intra-, and postoperative information and the potential effect on the retreatment outcome were evaluated and statistically analyzed using the chi-square test. RESULTS: Twenty-two patients with 23 teeth attended the follow-up examinations (recall rate = 92%). The follow-up periods ranged from 12 to 102 months (median = 35 months). Twenty teeth (87%) were classified as "success," and 3 teeth were considered (17%) "failure." The chi-square test confirmed that the preoperative factor "number of roots" had a statistically significant effect on treatment outcome (odds ratio = 0.08; 95% confidence interval, 0-1.76; P = .03). The factor "tooth location" was of borderline significance (odds ratio = 0.1; 95% confidence interval, 0-2.14; P = .05). CONCLUSIONS: The results of the present study suggest that orthograde retreatment combined with orthograde placement of an apical mineral trioxide aggregate plug is a promising long-term treatment option for teeth with postsurgical pathosis. The success rates were higher for single-rooted teeth. The use of cone-beam computed tomographic imaging in cases of inconclusive periapical radiographs is recommended to minimize the risk of misinterpretation when assessing treatment outcome.

Treatment outcome of mineral trioxide aggregate: repair of root perforations-long-term results.

INTRODUCTION: This historical cohort study follows on a previously reported trial, with the aim of assessing the outcome for teeth with root perforations managed by the orthograde placement of mineral trioxide aggregate (MTA) and identifying potential outcome factors for such treatment with a larger sample size and longer follow-up periods than in the first phase of the project. METHODS: The treatment outcomes of 64 root perforations repaired between 2000 and 2012 with MTA were investigated. The root perforations were located in different areas of the root. Calibrated examiners assessed clinical and radiographic outcomes by using standardized follow-up protocols 12-107 months after treatment (median, 27.5 months). Preoperative, intraoperative, and postoperative information was evaluated. The outcomes were dichotomized as healed or diseased. RESULTS: Of the 64 teeth examined (85% recall rate), 86% were healed. The univariate analyses (χ(2) tests) identified 2 potential prognostic factors, experience of the treatment providers (odds ratio, 2.14; 95% confidence interval, 0.39-11.74; P < .01) and placement of a post after treatment (odds ratio, 0.06; 95% confidence interval, 0.01-0.27; P < .01). In the multivariate stepwise logistic Cox regression, none of the potential prognostic factors displayed a significant effect on the outcome at the 5% level. CONCLUSIONS: MTA appears to have good long-term sealing ability for root perforations regardless of the location. The results of this historical cohort study confirm the results of the first phase of this project.

Treatment outcome of mineral trioxide aggregate or calcium hydroxide direct pulp capping: long-term results.

INTRODUCTION: This controlled, historic cohort study project continues a previously reported trial aiming to assess treatment outcome of direct pulp capping with mineral trioxide aggregate (MTA) versus calcium hydroxide (CH). Potential prognostic factors were re-evaluated on the basis of a larger sample size and longer follow-up periods. METHODS: Clinical and radiographic outcomes of 229 teeth treated with direct pulp capping between 2001 and 2011 were investigated 24 up to 123 months post-treatment (median = 42 months). Pre-, intra-, and postoperative information was evaluated and statistically analyzed using a logistic regression model as well as generalized estimating equation logit models. RESULTS: Two hundred five patients (229 teeth) were available for follow-up (74% recall rate). The overall success rates were 80.5% (95% confidence interval [CI], 74.5-86.5) of teeth in the MTA group (137/170) and 59% (95% CI, 46.5-71.5) of teeth in the CH group (35/59). Multivariate analyses (generalized estimating equation logit model) indicated a significantly increased risk of failure for teeth that were directly pulp capped with CH compared with MTA (odds ratio = 2.67; 95% CI, 1.36-5.25; P = .001). Teeth that were permanently restored ≥ 2 days after direct pulp capping had a significantly worse prognosis irrespective of the pulp capping material chosen (odds ratio = 3.18; 95% CI, 1.61-6.3; P = .004). CONCLUSIONS: The results of this study indicate that MTA provides better long-term results after direct pulp capping compared with CH. Placing a permanent restoration immediately after direct pulp capping is recommended.

Treatment outcome of mineral trioxide aggregate in open apex teeth.

INTRODUCTION: This cohort study is the second phase of a previously reported trial. The primary aim was to assess the outcome of the treatment of teeth with open apices managed by the orthograde placement of mineral trioxide aggregate (MTA) apical plugs. The secondary goal was to identify potential outcome factors for this kind of treatment with a larger sample size and longer follow-up periods than in the first phase of the project. METHODS: Two hundred twenty-one patients who had been treated between 2000 and 2010 were contacted for follow-up examination 12-128 months after treatment (median, 21 months). At the time of treatment, these patients presented a total of 252 teeth with open apices caused by apical root resorption or excessive apical enlargement or with immature apices. Treatment was performed by supervised undergraduate students (12% of teeth), general dentists (49%), and dentists whose practice was limited to endodontics (39%). The investigated outcome relied on clinical and radiographic criteria and was dichotomized as healed or diseased. RESULTS: Of 252 examined teeth (88% recall rate), 90% were healed. Teeth with and without preoperative periapical radiolucencies demonstrated healed rates of 85% and 96%, respectively. Forty-five percent of the teeth (113/252) were followed up at least 2 years later and 21% (53/252) at least 4 years later. Univariate survival analyses identified 4 prognostic factors: preoperative apical periodontitis, the experience of the treatment providers, the number of treatment sessions, and the apical extrusion of MTA. Multiple regression analyses confirmed an increased risk of disease for teeth with preoperative apical periodontitis (hazard ratio = 4.59; 95% confidence interval, 1.57-13.4; P = .005). In addition, the experience of the treatment provider was found to influence the outcome (hazard ratio = 0.25; 95% confidence interval, 0.09-0.75; P = .03). CONCLUSIONS: Orthograde placement of MTA apical plugs appears to be a promising treatment option for teeth with open apices. The healed rates for such teeth were high in this study, even after follow-up periods of more than 4 years. The presence of preoperative apical periodontitis was identified as an important prognostic factor.

Recontouring teeth and closing diastemas with direct composite buildups: a clinical evaluation of survival and quality parameters.

OBJECTIVES: Irregular tooth shape and position in the anterior maxilla and mandible are major aesthetic problems for patients. In recent years such conditions have increasingly been treated minimally or even non-invasively by recontouring teeth with direct composite resin buildups. Although clinical experience with this treatment option is promising, evidence-based data about longevity are limited. METHODS: The authors evaluated survival and quality of 327 composite buildups that were placed in 101 patients in the Department of Conservative Dentistry, University of Heidelberg, between 2002 and 2008. Follow-up intervals and failures were recorded. Quality was assessed by grading restorations (modified USPHS/Ryge critera) still in situ without adverse event during the follow-up period. RESULTS: After a mean follow-up interval of 27.8 months, 284 restorations were in situ and had no event. Forty-two restorations were in situ but had events that were mostly minor fractures of the composite resin. One restoration had been lost. Analysis of the time from insertion to any event or end of follow-up yielded an estimated 5-year survival rate of 79.2% (95% CI, 70.5-87.9). Quality was assessed by grading in situ restorations without event. More than 90% of graded restorations were categorized as "clinically excellent" (1) or "clinically good" (2). A correlation between those rated "clinically sufficient" or worse (≥3) and the follow-up period was observed. CONCLUSIONS: Direct composite buildups are aesthetic, functional, and biologically sound treatment options for recontouring teeth and closing diastemas with clinically promising survival rates. Therefore, tooth shape correction can be recommended in cases in which minimally invasive or non-invasive procedures on healthy teeth are indicated.

Treatment outcome of mineral trioxide aggregate: repair of root perforations.

INTRODUCTION: The use of biocompatible materials like mineral trioxide aggregate (MTA) may improve the prognosis of teeth with root perforations. METHODS: The treatment outcome of root perforations repaired between 2000 and 2006 with MTA was investigated. Twenty-six patients received treatment with MTA in 26 teeth with root perforations. Treatment was performed by supervised undergraduate students (29%), general dentists (52%), or dentists who had focused on endodontics (19%). Perforation repair by all treatment providers was performed using a dental operating microscope. Calibrated examiners assessed clinical and radiographic outcome 12 to 65 months after treatment (median 33 months, 81% recall rate). Pre-, intra-, and postoperative information relating to potential prognostic factors was evaluated. RESULTS: Of 21 teeth examined, 18 teeth (86%) were classified as healed. None of the analyzed potential prognostic factors had a significant effect on the outcome. CONCLUSIONS: MTA appears to provide a biocompatible and long-term effective seal for root perforations in all parts of the root.

Relationship between microtensile bond strength and submicron hiatus at the composite-dentin interface using CLSM visualization technique.

OBJECTIVES: "Submicron hiatus" represents a potential space between the base of the collagenous network and the mineralized dentin when it is acid etched for bonding. This study evaluated the relationship between microtensile bond strength (microTBS) and occurrence of submicron hiatus formations at the resin-dentin interface using the same specimens. METHODS: Resin-dentin bonded micro-specimens (sticks with a size of 300 microm x 300 microm x 8mm) were prepared using one of two material combinations (group I: Syntac Classic/Tetric Ceram Cavifil: n=51 group II: Prime & Bond NT/Tetric Ceram Cavifil: n=56). After labeling the primer component with a tiny amount of rhodamine-B-isothiocyanate, submicron hiatus formations were imaged nondestructively using a confocal laser scanning microscope (CLSM). Subsequently specimens were subjected to a microTBS test. RESULTS: For the influence of submicron hiatus formations on microTBS with the Syntac Classic group, the nonparametric Spearman's correlation was -0.329 at p=0.02. For the Prime & Bond NT group, the nonparametric Spearman's correlation was -0.356 at p=0.007. Analyzing the effect of submicron hiatus on without discriminating by group resulted in a Spearman's correlation coefficient of -0.341 at p=0.001; microTBS and quality of hybrid layer showed a correlation coefficient of 0.849 at p=0.001, and microTBS and quality of tag formation showed a correlation coefficient of 0.474 at p=0.001. SIGNIFICANCE: The degree of submicron hiatus formations had an influence on microtensile bond strength for both the Syntac Classic and the Prime & Bond NT group.