Impact of acquisition volume on cone beam computed tomography imaging of marginal bone: an ex vivo study.

OBJECTIVE: The current study explores whether there is a clinically relevant distinction in the measurement of marginal bone loss when comparing high-dose (HD) versus low-dose (LD) cone beam computed tomography (CBCT) protocols in small and large acquisition volumes.  Material and Methods: CBCTs of four human cadaveric preparates were taken in HD and LD mode in two different fields of view 8 × 8 cm2 (LV) and 5 × 5 cm2 (SV). In total, 43 sites of 15 teeth were randomly chosen, and marginal bone loss was measured twice in all protocols at 43 sites of 15 teeth by one calibrated investigator. Bland-Altman plots and Lin's concordance correlation coefficient (CCC) were calculated to assess the extent of agreement of the measurements. Additionally, the rater scored the certainty in each of the measurements. RESULTS: For HD-CBCT CCC of measurements obtained using SV versus LV was 0.991. CCC of measurements obtained using SV versus LV of LD-CBCT was 0.963. Both CCC values indicated excellent agreement between the two volumes in both protocols.  CCC also indicated high intramodality correlation between HD-CBCT and LD-CBCT independent of the acquisition volume (0.963 - 0.992). Bland-Altman plots also indicated no substantial differences. Results of certainty scoring showed significant differences (p = 0.004 (LV), p < 0.001(SV)) between the LD and HD-CBCT. CONCLUSIONS: Accuracy of measurements of bone loss shows no clinical noticeable effects depending on the CBCT volume in this ex vivo study. There appears to be no relevant advantage of SV over LV, neither in HD-CBCT nor in LD-CBCT and additionally no relevant advantage of HD versus LD in visualizing marginal bone loss.

Dental imaging in clinical photon-counting CT at a quarter of DVT dose.

OBJECTIVE: To investigate the image quality of a low-dose dental imaging protocol in the first clinical photon-counting computed tomography (PCCT) system in comparison to a normal-dose acquisition in a digital volume tomography (DVT) system. MATERIALS AND METHODS: Clinical PCCT systems offer an increased spatial resolution compared to previous generations of clinical systems. Their spatial resolution is in the order of dental DVT systems. Resolution-matched acquisitions of ten porcine jaws were performed in a PCCT (Naeotom Alpha, Siemens Healthineers) and in a DVT (Orthophos XL, Dentsply Sirona). PCCT images were acquired with 90 kV at a dose of 1 mGy CTDI16 cm. DVT used 85 kV at 4 mGy. Image reconstruction was performed using the standard algorithms of each system to a voxel size of 160 × 160 × 200 µm. The dose-normalized contrast-to-noise ratio (CNRD) was measured between dentine and enamel and dentine and bone. Two readers evaluated overall diagnostic quality of images and quality of relevant structures such as root channels and dentine. RESULTS: CNRD is higher in all PCCT acquisitions. CNRD is 37 % higher for the contrast dentine-enamel and 31 % higher for the dentine-bone contrast (p < 0.05). Overall diagnostic image quality was higher for PCCT over DVT (p < 0.02 and p < 0.04 for readers 1 and 2). Quality scores for anatomical structures were higher in PCCT compared to DVT (all p < 0.05). Inter- and intrareader reproducibility were acceptable (all ICC>0.64). CONCLUSIONS: PCCT provides an increased image quality over DVT even at a lower dose level and might enable complex dental imaging protocols in the future. CLINICAL SIGNIFICANCE: The evolution of photon-counting technology and it's optimization will increasingly move dental imaging towards standardized 3D visualizations providing both minimal radiation exposure and high diagnostic accuracy.

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.

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.

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.

Dental imaging using an ultra-high resolution photon-counting CT system.

Clinical photon-counting CT (PCCT) offers a spatial resolution of about 200 µm and might allow for acquisitions close to conventional dental CBCTs. In this study, the capabilities of this new system in comparison to dental CBCTs shall be evaluated. All 8 apical osteolysis identified in CBCT were identified by both readers in all three PCCT scan protocols. Mean visibility scores showed statistical significant differences for root canals(p = 0.0001), periodontal space(p = 0.0090), cortical(p = 0.0003) and spongious bone(p = 0.0293) in favor of high and medium dose PCCT acquisitions. Overall, both devices showed excellent image quality of all structures assessed. Interrater-agreement showed high values for all protocols in all structures. Bland-Altman plots revealed a high concordance of both modalities with the reference measurements. In vitro, ultra-high resolution PCCT can reliably identify different diagnostic entities and structures relevant for dental diagnostics similar to conventional dental CBCT with similar radiation dose. Acquisitions of five cadaveric heads were performed in an experimental CT-system containing an ultra-high resolution PC detector (0.25 mm pixel size in isocenter) as well as in a dental CBCT scanner. Acquisitions were performed using dose levels of 8.5 mGy, 38.0 mGy and 66.5 mGy (CTDI16cm) in case of PCCT and of 8.94 mGy (CTDI16cm) in case of CBCT. The quality of delineation of hard tissues, root-canals, periodontal-space as well as apical osteolysis was assessed by two readers. Mean visibility scores and interrater-agreement (overall agreement (%)) were calculated. Vertical bone loss (bl) and thickness (bt) of the buccal bone lamina of 15 lower incisors were measured and compared to reference measurements by ore microscopy and clinical probing.

Imaging furcation defects with low-dose cone beam computed tomography.

Different cone beam computed tomography (CBCT) protocols have shown promising results for imaging furcation defects. This study evaluates the suitability of low-dose (LD)-CBCT for this purpose. Fifty-nine furcation defects of nine upper and 16 lower molars in six human cadavers were measured by a high-dose (HD)-CBCT protocol, a LD-CBCT protocol, and a surgical protocol. HD-CBCT and LD-CBCT measurements were made twice by two investigators and were compared with the intrasurgical measurements, which served as the reference. Furcation defect volumes generated from HD-CBCT and LD-CBCT imaging were segmented by one rater. Cohen's kappa and intraclass correlation coefficient (ICC) values were calculated to determine intra- and interrater reliability. The level of significance was set at α = 0.05. In total, 59 furcation defects of nine upper and 16 lower human molars were assessed. Comparing CBCT furcation defect measurements with surgical measurements revealed a Cohen's kappa of 0.5975 (HD-and LD-CBCT), indicating moderate agreement. All furcation defects identified by HD-CBCT were also detected by LD-CBCT by both raters, resulting in a Cohen's kappa of 1. For interrater agreement, linear furcation defect measurements showed an ICC of 0.992 for HD-CBCT and 0.987 for LD-CBCT. The intrarater agreement was 0.994(r1)/0.992(r2) for HD-CBCT and 0.987(r1)/0.991(r2) for LD-CBCT. The intermodality agreement was 0.988(r1)/0.991(r2). Paired t-test showed no significant differences between HD-CBCT and LD-CBCT measurements. LD-CBCT is a precise and reliable method for detecting and measuring furcation defects in mandibular and maxillary molars in this experimental setting. It has the potential to improve treatment planning and treatment monitoring with a far lower radiation dose than conventional HD-CBCT.

Low-dose CBCT imaging of alveolar buccal bone adjacent to mandibular anterior teeth- a pilot study.

OBJECTIVES: Accurate description of buccal bone adjacent to mandibular anterior teeth is helpful for planning and monitoring periodontal and orthodontic treatment. Low-dose cone beam computed tomography (LD-CBCT) imaging has shown promising results for very small dental structures in animals. This study asserts that LD-CBCT is sufficiently accurate to measure buccal alveolar bone adjacent to human mandibular anterior teeth. MATERIALS AND METHODS: Buccal bone level adjacent to 16 mandibular anterior teeth from four human cadavers was measured radiographically using one high-dose (HD) CBCT protocol and two LD-CBCT protocols. The resulting radiographic measurements of buccal bone height (bl) and thickness (bt) were compared with reference probe and reflected-light microscopy measurements. Measurement medians and Bland-Altman plots were calculated, and a linear mixed model was used to compare raters and imaging modalities. RESULTS: All regression coefficients were approximately 0, indicating high interrater, intrarater, and intermodality agreement. No significant differences were found between reference measurements and CBCT protocols. The mean differences for bl measurements were 0.07 mm (rater 1 [r1]) and 0.12 mm (rater 2 [r2]) for HD-CBCT; 0.07 mm (r1) and 0.13 mm (r2) for LD-CBCT-1; and 0.02 mm (r1) and 0.01 mm (r2) for LD-CBCT-2. For bt measurements, mean differences were 0.02 mm (r1) and 0.02 mm (r2) for HD-CBCT; 0.01 mm (r1) and 0.01 mm (r2) for LD-CBCT-1; and 0.00 mm (r1) and 0.01 mm (r2) for LD-CBCT-2. CONCLUSIONS: Within the limitations of the present study, LD-CBCT seems to be a precise method for describing buccal bone and its thickness adjacent to mandibular anterior teeth in this experimental setting. CLINICAL RELEVANCE: For the first time, this study showed LD-CBCT produces excellent results and is a reliable modality for imaging buccal bone in vitro. If clinical studies confirm these results, LD-CBCT could enable better treatment planning and monitoring at a radiation dose that is far lower than that of conventional HD-CBCT but similar to that of panoramic views.

Prevalence of endo-perio lesions according to the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Disease in a university hospital.

OBJECTIVES: Teeth with combined endodontic-periodontal lesions (EPLs) have favorable to hopeless prognoses. The new classification system was developed by the World Workshop on the Classification of Periodontal and Peri-Implant Disease in 2017 and suitable epidemiologic data related to this new system are currently lacking. This study aims to contribute data about the prevalence of EPLs according to the new system. METHOD AND MATERIALS: A total of 1,008 panoramic views taken in 2019 were analyzed, recording the presence of an EPL and other periodontic parameters. Radiographs of bad quality and of the same person were excluded. Additionally, the EPLs' radiographic patterns were rated by two raters according to their shape (j-shaped vs cone-shaped). Descriptive statistical methods as well as t tests for continuous and chi-squared tests for categorical variables were used. RESULTS: Overall, 866 patients (with 18,963 teeth) were included. Prevalence of EPLs was 4.9% (n = 43) (patient-related)/0.4% (n = 71) (tooth-related). Mean age (62.3 years vs 51.5 years), mean maximal percentage of bone loss (60% vs 30%), and mean age-adjusted bone-loss index (1.0 vs 0.6) were considerably higher compared to patients without EPL. A total of 67 EPLs were found in patients with stage III/IV periodontitis and 4 in patients with stage II periodontitis. CONCLUSIONS: This is the first study showing prevalence of EPLs (4.9%/0.4%) according to the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Disease. Patients with EPLs have a substantially higher maximal percentage of bone loss and a higher age-adjusted bone-loss index at residual teeth, excluding teeth with EPLs. All patients have at least stage II periodontitis.

Ex-vivo imaging of buccal and oral periodontal bone with low-dose CBCT in porcine jaws.

OBJECTIVES: New CBCT devices have been developed which can provide "low-dose CBCTs (LD-CBCT)". Aim of this study is to investigate the suitability of LD-CBCT for measurement of alveolar buccal/oral bone. METHODS AND MATERIALS: Vestibular and oral bone loss of the teeth of seven porcine mandibles free of soft tissues were investigated by Micro-CT and three CBCT-modes: high-dose (HD), standard-dose (SD) and low-dose (LD). Radiographic measurements of bone loss (bl) and vestibular and oral bone thickness (bt) were made by two raters at 69 sites. Measurement means and differences, Intraclass correlation (ICC) and Bland-Altman plots were calculated. RESULTS: ICCs between raters(r) concerning bl were 0.954 for HD, 0.949 for SD and 0.945 for LD; concerning bt they were 0.872 for HD, 0.845 for SD and 0.783 for LD. Means of differences of bt measurements were -0.01 mm(r1)/0.00 mm(r2) for HD, 0.04 mm(r1)/0.02 mm(r2) for SD and 0.02 mm(r1)/0.04 mm(r2) for LD; for bl measurements they were 0.06 mm(r1)/0.05 mm(r2) for HD, -0.01 mm(r1)/0.13 mm(r2) for SD and 0.07 mm(r1)/0.16 mm(r2) for LD.Linear regression indicates no noticeable differences between methods and the raters with respect to bl and bt. CONCLUSIONS: Relating to the CBCT-device used in this study, LD-CBCT is a promising method to detect and describe buccal and oral periodontal bl and bt. Further studies with human anatomic structures must confirm these results.

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.

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.

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 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.