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.

Retention of molars after root-resective therapy: a retrospective evaluation of up to 30 years.

OBJECTIVES: Long-term retention of teeth and especially molars in function is the ultimate goal of periodontal therapy. Root-resective therapy is a treatment option for molars with advanced furcation involvement, which has been questioned because of the heterogenous success rates published in literature. This study aimed to evaluate long-term results of root-resective treatment over a period of up to 30 years. METHODS: In this retrospective cohort, 90 root-resected molars in 69 patients were examined for 4-30 years (14.7 ± 6.8 years). The complete treatment sequence was performed by one of the authors in a general dental practice. RESULTS: Overall cumulative survival rate was 90.6% after 10 years, but then decreased considerably. Molars after root resection had a median survival time of 20 years. The incidence of endodontic complications leading to tooth extraction was only 26.7%, 50% were lost due to periodontal problems, and 16.7% because of caries. Mandibular molars had a significantly lower relative risk of loss than molars in the maxilla (HR 0.31, 95% CI 0.1-0.91, p = 0.033). Mandibular molars showed a survival probability of almost 80% even 20 years after root resection. CONCLUSION: Root-resective therapy is a predictable treatment option, when care is administered at each phase of therapy. CLINICAL RELEVANCE: This study provides important information about what is possible in daily practice under the outlines of public health care, when care is administered at each phase of resective therapy.

Endodontic status and retention of molars in periodontally treated patients: results after 10 or more years of supportive periodontal therapy.

OBJECTIVES: To assess the influence of endodontic status on retention of molars in patients under supportive periodontal treatment (SPT). MATERIAL & METHODS: A total of 136 subjects with 1015 molars at baseline were examined retrospectively, including 188 endodontically treated molars in 90 patients. Multilevel Cox regression analysis identified factors contributing to loss of molars. RESULTS: Root canal treatments contributed significantly to loss of molars during on average 13.2 years of SPT (Hazard ratio: 2.98, 95% CI: 1.74-5.1, p < 0.001). Endodontic treatment was more frequently present in first molars (p < 0.001) and in the maxilla (p = 0.01). In endodontically treated molars, degree III furcation involvement could be detected more often compared to molars without root canal treatment (p < 0.001). Among the root canal-treated molars, several patient and tooth-related factors showed an impact on tooth retention, but only molars with a periapical index of 4 and 5 (labelled "diseased") were significantly more often lost. CONCLUSION: The retention of molars in periodontally compromised patients after periodontal treatment is influenced by periodontal as well as endodontal factors. On a long-term basis, it is feasible to retain these teeth via active periodontal treatment and SPT for more than 10 years.

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.

Loss of molars in periodontally treated patients: results 10 years and more after active periodontal therapy.

AIM: To identify risk factors for loss of molars during supportive periodontal therapy (SPT). MATERIALS AND METHODS: A total of 136 subjects with 1015 molars at baseline were examined retrospectively. The association of risk factors with loss of molars was assessed using a multilevel Cox regression analysis. Furcation involvement (FI) was assessed clinically at start of periodontal therapy and assigned according to Hamp et al. (1975). RESULTS: Fifty molars were extracted during active periodontal therapy (APT) and 154 molars over the average SPT period of 13.2 ± 2.8 years. FI degree III (HR 4.68, p < 0.001), baseline bone loss (BL) > 60% (HR 3.74, p = 0.009), residual mean probing pocket depth (PPD, HR 1.43, p = 0.027), and endodontic treatment (HR 2.98, p < 0.001) were identified as relevant tooth-related factors for loss of molars during SPT. However, mean survival time for molars with FI III or BL > 60% were 11.8 and 14.4 years, respectively. Among the patient data, age (HR 1.57, p = 0.01), female gender (HR 1.99, p = 0.035), smoking (HR 1.97, p = 0.034), and diabetes mellitus (HR 5.25, p = 0.021) were significant predictors for loss of molars. CONCLUSION: Overall, periodontal therapy results in a good prognosis of molars. Degree III FI, progressive BL, endodontic treatment, residual PPD, age, female gender, smoking, and diabetes mellitus strongly influence the prognosis for molars after APT.

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 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: 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 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.

Mineral trioxide aggregate or calcium hydroxide direct pulp capping: an analysis of the clinical treatment outcome.

INTRODUCTION: The use of mineral trioxide aggregate (MTA) might improve the prognosis of teeth after pulp exposure. The treatment outcome of teeth after direct pulp capping, either with mineral trioxide aggregate (MTA) or calcium hydroxide (controls), was investigated, taking into account possible confounding factors. METHODS: One hundred forty-nine patients treated between 2001 and 2006 who received direct pulp capping treatment in 167 teeth met the inclusion criteria. Treatment was performed by supervised undergraduate students (72%) and dentists (28%). Assessment of clinical and radiographic outcomes was performed by calibrated examiners 12-80 months after treatment (median, 27 months). RESULTS: One hundred eight patients (122 treated teeth) were available for follow-up (72.5% recall rate). A successful outcome was recorded for 78% of teeth (54 of 69) in the MTA group and for 60% of teeth (32 of 53) in the the calcium hydroxide group. The univariate analysis (generalized estimation equations model [GEE model] showed a significant difference in the success rate (odds ratio [OR], 2.36; 95% confidence interval [CI], 1.05-5.32; P = .04). In the multiple analysis (GEE model), the OR is marginally inside the nonsignificant range (OR, 0.43; 95% CI, 0.19-1.02; P = .05) when conspicuous confounding factors are stabilized (univariate analysis). Multiple analysis showed that teeth that were permanently restored >or=2 days after capping had a significantly worse prognosis in both groups (OR, 0.24; 95% CI, 0.09-0.66; P = .01). CONCLUSIONS: MTA appears to be more effective than calcium hydroxide for maintaining long-term pulp vitality after direct pulp capping. The immediate and definitive restoration of teeth after direct pulp capping should always be aimed for.

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.

Mineral trioxide aggregate apical plugs in teeth with open apical foramina: a retrospective analysis of treatment outcome.

INTRODUCTION: Teeth with open apical foramina present a challenge during root canal treatment, and little is known about the clinical outcome of treatment in such teeth. This retrospective study assessed healing of teeth with open apices managed by the placement of mineral trioxide aggregate apical plugs. METHODS: Seventy-two patients with 78 teeth with apical resorption or excessive apical enlargement, treated between 2000 and 2006, were contacted for follow-up examination 12 to 68 months after treatment (median 30.9 months). Treatments were provided by supervised undergraduate students (27%), general dentists (32%), or dentists who had focused on endodontics (41%). The outcome based on clinical and radiographic criteria was assessed by calibrated examiners and dichotomized as "healed" or "disease." RESULTS: Of 56 teeth examined (72% recall), 84% were healed. Teeth without or with preoperative periapical radiolucency had a healed rate of 100% and 78%, respectively. None of the variables analyzed had a significant effect on the outcome. CONCLUSION: The results supported the management of open apical foramina with mineral trioxide aggregate apical plugs.