Buccal plate thickness as a predictor for endodontic microsurgery outcomes: A retrospective cohort study.

OBJECTIVE: The aim of the study was to determine the relationship between preoperative buccal plate thickness (BPT) and radiographic healing at the osteotomy site after endodontic microsurgery (EMS) with and without guided tissue regeneration (GTR) using cone beam computed tomography (CBCT) imaging. STUDY DESIGN: The retrospective sample of 143 individuals who had EMS with pre- and postoperative CBCT scans available were divided into 2 groups: group 1 (GTR) and group 2 (no GTR), which were further divided into teeth where BPT was >1.0 mm or ≤1.0 mm. Bone healing was assessed by subjective evaluation of bone formation at the resected root surface (I1), periapical bone formation (I2), cortical plate formation (I3), and a derived index (Author2-Author1 Indices) (I4), calculated by a composite score of I1 and I2. RESULTS: There was no significant impact on surgical healing with the use of GTR when BPT is >1.0 mm. The GTR had a significant impact on surgical healing when the BPT was ≤1.0 mm. CONCLUSIONS: This study supported the use of CBCT to evaluate three-dimensional healing after EMS. The Author2-Author1 index was found to be a clinically relevant method for assessing healing. To improve healing rate, the EMS cases with a preoperative BPT of ≤1.0 mm may benefit from GTR.

Comparison of endodontic diagnosis and treatment planning decisions using cone-beam volumetric tomography versus periapical radiography.

INTRODUCTION: Accurate and confident treatment planning is an essential part of endodontic practice. Periapical radiographs have been used to aid in the diagnosis of pathology and to help establish an appropriate treatment strategy. Recently, a new imaging modality, cone-beam volumetric tomographic (CBVT) imaging, has been shown to be a useful tool in a number of endodontic applications. The aim of this study was to compare the relative value of preoperative periapical radiographs and CBVT scanning in the decision-making process in endodontic treatment planning. METHODS: Thirty endodontic cases completed in a private endodontic practice were randomly selected to be included in this study. Each case was required to have a preoperative digital periapical radiograph and a CBVT scan. Three board-certified endodontists reviewed the 30 preoperative periapical radiographs. Two weeks later, the CBVT volumes were reviewed in random order by the same evaluators. The evaluators were asked to select a preliminary diagnosis and treatment plan based solely on their interpretation of the periapical and CBVT images. Diagnosis and treatment planning choices were then compared to determine if there was a change from the periapical radiograph to the CBVT scan. RESULTS: A difference in treatment plan between the 2 imaging modalities was recorded in 19 of 30 cases (63.3%, P = .001), 17 of 30 cases (56.6%, P = .012), and 20 of 30 cases (66.7%, P = .008) for examiners 1, 2, and 3, respectively. CONCLUSIONS: Under the conditions of this study, preoperative CBVT imaging provides additional information when compared with preoperative periapical radiographs, which may lead to treatment plan modifications in approximately 62% of the cases.

Different representations of vertical root fractures detected by cone-beam volumetric tomography: a case series report.

INTRODUCTION: Vertical root fractures (VRFs) pose a clinical dilemma and a challenge to clinicians. Definitive diagnosis is often complicated by the lack of consistent signs and symptoms and the low sensitivity of conventional radiographs in the detection of VRFs. New radiographic imaging systems have recently become available for use in dentistry. Among these new imaging technologies is cone-beam volumetric tomography (CBVT). CBVT technology allows the precise visualization and evaluation of teeth with VRFs. The use of CBVT has great potential as a diagnostic tool to assist in the detection of VRFs. METHODS: Seven cases are presented to demonstrate the use of CBVT in detection of VRFs in endodontically treated teeth. RESULTS: Five specific findings on CBVT exam were consistent with confirmed VRFs. CONCLUSIONS: As demonstrated in this case series, CBVT can provide valuable additional diagnostic information in the detection of VRFs and may help prevent unnecessary treatment.

Efficacy of berberine, an antimicrobial plant alkaloid, as an endodontic irrigant against a mixed-culture biofilm in an in vitro tooth model.

INTRODUCTION: Berberine, a plant alkaloid isolated from many medicinal plants, has shown antimicrobial activity against selected oral pathogens. The purpose of this investigation was to evaluate the antimicrobial efficacy of berberine solution against selected endodontic pathogens using a multispecies biofilm tooth model. METHODS: The bacterial species used in the multispecies biofilm tooth model were Fusobacterium nucleatum, Enterococcus faecalis, and Prevotella intermedia. Extracted human anterior teeth were collected and standardized to a length of 14.0 mm. Teeth were cultured in Schaedler broth with the 3 test bacteria strains for 21 days and then randomly assigned to 6 treatment groups (ie, sterile saline, 5.25% NaOCl, 2% chlorhexidine [CHX], 1% CHX, 2 mg/mL berberine, and 1 mg/mL berberine plus 1% CHX). The teeth were instrumented to size 35/.06 and irrigated with 6 mL irrigant for 2 minutes. Surviving bacteria were sampled before and after instrumentation. Data were analyzed using analysis of variance (P < .05) followed by the Scheffé test. RESULTS: The minimal inhibitory concentration of berberine against F. nucleatum, P. intermedia, and E. faecalis was 31.25 µg/mL, 3.8 µg/mL, and 500 µg/mL, respectively. Instrumentation and irrigation resulted in 99% bacterial reduction in all groups. All tested solutions resulted in a statistically significant reduction in bacteria when compared with the saline control. When used alone, berberine (2 mg/mL) was less effective than the other test irrigants. However, when combined with 1% CHX, berberine (2 mg/mL) was comparable in bactericidal activity with 5.25% NaOCl, 2% CHX, and 1% CHX (Table 2). CONCLUSIONS: Berberine was more effective than saline as an endodontic irrigant against selected endodontic pathogens in vitro and, when combined with CHX, was comparable with NaOCl in its bactericidal efficacy.

Biomimetic approach to perforation repair using dental pulp stem cells and dentin matrix protein 1.

INTRODUCTION: Dentin regeneration could be an ideal treatment option to restore tissue function. This study was conducted to evaluate the ability of dental pulp stem cells (DPSCs) and dentin matrix protein 1 (DMP1) impregnated within a collagen scaffold to regenerate dentin. METHODS: Simulated perforations were created in 18 dentin wafers made from freshly extracted human molars. Six groups were established. They were (1) empty wafers, (2) mineral trioxide aggregate, (3) collagen scaffold, (4) scaffold with DMP1, (5) scaffold with DPSCs, and (6) scaffold with DPSCs and DMP1. One sample was placed subcutaneously in each mouse with three mice in each group. After 12 weeks, the samples were subjected to radiographic, histological, and immunohistochemical evaluations. RESULTS: DPSCs impregnated within a collagen scaffold differentiated into odontoblast-like cells forming a highly cellular, vascular, and mineralized matrix in the presence of DMP1. CONCLUSIONS: A triad consisting of DPSCs, DMP1, and a collagen scaffold promotes dentin regeneration in a simulated perforation repair model.

Biologic markers for odontogenic periradicular periodontitis.

INTRODUCTION: The diagnosis and assessment of apical periodontitis by traditional periapical radiographs can be challenging and might yield false-negative results. The aim of this study was to determine whether interleukin-1beta (IL-1beta) and dentin sialoprotein (DSP) in gingival crevicular fluid (GCF) can be used as biological markers for apical periodontitis. METHODS: Forty healthy patients with teeth diagnosed with apical periodontitis of pulpal origin were included in the study. GCF samples were obtained from the diseased tooth and from a healthy contralateral control tooth. Total protein concentration in each sample was determined by using the Bio-Rad protein assay. Enzyme-linked immunosorbent assay was used to analyze the concentration of IL-1beta and DSP in the samples. RESULTS: Protein content of the GCF was statistically significantly higher in the disease group compared with the control group. The levels of IL-1beta and DSP were not statistically different between disease and control groups. CONCLUSIONS: Although this study was unable to demonstrate a significantly higher level of IL-1beta or DSP in the GCF of teeth with apical periodontitis, the observed presence of a significantly higher level of total protein in the GCF of diseased teeth suggests the possible role of total protein level as a marker for periapical disease.

In vivo generation of dental pulp-like tissue by using dental pulp stem cells, a collagen scaffold, and dentin matrix protein 1 after subcutaneous transplantation in mice.

The presence of a perforation is known to significantly compromise the outcome of endodontic treatment. One potential use of regenerative endodontic therapy might be the repair of root canal perforations. In addition to nutrients and systemic in situ interactions, the 3 main components believed to be essential for tissue regeneration are stem cells, scaffold, and growth factors. This study investigated the role of each component of the tissue engineering triad in the organization and differentiation of dental pulp stem cells (DPSCs) in a simulated furcal perforation site by using a mouse model. Collagen served as the scaffold, and dentin matrix protein 1 (DMP1) was the growth factor. Materials were placed in simulated perforation sites in dentin slices. Mineral trioxide aggregate was the control repair material. At 6 weeks, the animals were killed, and the perforation sites were evaluated by light microscopy and histologic staining. Organization of newly derived pulp tissue was seen in the group containing the triad of DPSCs, a collagen scaffold, and DMP1. The other 4 groups did not demonstrate any apparent tissue organization. Under the conditions of the present study, it might be concluded that the triad of DPSCs, a collagen scaffold, and DMP1 can induce an organized matrix formation similar to that of pulpal tissue, which might lead to hard tissue formation.

Outcome of one-visit and two-visit endodontic treatment of necrotic teeth with apical periodontitis: a randomized controlled trial with one-year evaluation.

The choice of one-visit versus two-visit root canal therapy for necrotic teeth with apical periodontitis is a source of current debate. The primary objective of this randomized controlled clinical trial was to compare radiographic evidence of periapical healing after root canal therapy completed in one visit or two visits with an interim calcium hydroxide/chlorhexidine paste dressing. Ninety-seven patients met the inclusion criteria and consented to participate in this study. Patients were randomly assigned to either the one-visit or two-visit group, and root canal therapy was performed with a standardized protocol. Patients in the two-visit group received an intracanal dressing of calcium hydroxide/chlorhexidine paste. Sixty-three patients, 33 in the one-visit group and 30 in the two-visit group, were evaluated at 12 months. The primary outcome measure was change in apical bone density by using the periapical index (PAI). Secondary outcome measures were proportion of teeth healed or improved in each group. Both groups exhibited equally favorable periapical healing at 12 months, with no statistically significant differences between groups.

Antimicrobial effect of triclosan and triclosan with Gantrez on five common endodontic pathogens.

Microbial control of the root canal system is one of the key objectives of root canal therapy. Triclosan is a widely accepted broad spectrum antimicrobial agent proven to be effective against many gram-positive and gram-negative bacteria. Triclosan acts by blocking bacterial fatty acid biosynthesis. The addition of Gantrez copolymer has been shown to enhance the antimicrobial activity of triclosan. The purpose of this study was to determine the minimum inhibitory and bactericidal concentrations of triclosan and triclosan with Gantrez against Prevotella intermedia, Fusobacterium nucleatum, Actinomyces naeslundii, Porphyromonas gingivalis, and Enterococcus faecalis. The minimum inhibitory concentration (MIC) of both test solutions was determined for each of the 5 microorganisms by using microtiter serial dilutions. Samples were streaked on 5% sheep blood agar plates and placed in an anaerobic incubator to determine the minimum bactericidal concentration (MBC). The MBC of triclosan ranged from 12-94 microg/mL. The MBC of triclosan with Gantrez ranged from <0.3-10.4 microg/mL. The addition of Gantrez enhanced the bactericidal activity of triclosan. Both triclosan and triclosan with Gantrez demonstrated bactericidal activity against the 5 specific endodontic pathogens.

Application and assessment of a dipstick assay in the diagnosis of hydatidosis and trichinosis.

The aim of the present work was to apply and evaluate a dipstick assay for the serodiagnosis of human hydatidosis as well as human and experimental trichinosis using camel hydatid cyst fluid (HCF) and Trichinella spiralis muscle larval (TSML) antigens, respectively, and compare this to enzyme-linked immunoelectrotransfer blot (EITB) and Falcon assay screening test-enzyme-linked immunosorbent assay (FAST-ELISA). Sera samples were collected from patients with confirmed hydatidosis and trichinosis and with other parasitic diseases as well as from normal healthy individuals. Also, sera samples were collected from mice experimentally infected with T. spiralis which were sacrificed at different time points post-infection (PI). HCF and TSML antigens were used in EITB after separation and characterization of their antigenic components using 5-22.5% sodium dodecyl sulphate-polyacrylamide gel electrophoresis under non-reducing condition. For the diagnosis of hydatidosis, the sensitivity, specificity and diagnostic accuracy of the dipstick assay and EITB were 100, 91.4 and 95.1% while those of FAST-ELISA were 96.2, 100 and 98.4%, respectively. For the diagnosis of human trichinosis, the sensitivity, specificity and diagnostic accuracy of the dipstick assay and EITB were 100% while those of FAST-ELISA were 85.7%. FAST-ELISA proved to be more sensitive in the early diagnosis of experimental T. spiralis infection (100% sensitivity from the second week PI) than the dipstick and EITB (100% sensitivity from the third week PI). All tests retained their sensitivity till the 12th week PI. Since the dipstick assay is extremely easy to perform with a visually interpreted result within 15 min, in addition to being both sensitive and specific, the test could be an acceptable alternative for use in clinical laboratories lacking specialized equipment and the technological expertise needed for EITB and FAST-ELISA.

The effect of CO2 laser irradiation on PDL cell attachment to resected root surfaces.

OBJECTIVES: The effect of CO2 laser irradiation on PDL attachment to resected root ends was evaluated. STUDY DESIGN: Forty dentin wafers were divided into 4 equal groups. Groups I and II were not subjected to laser irradiation. Groups III and IV were subjected to irradiation with CO2 laser (wave length 10.6 mm). PDL cells attachment to the resected root surface (lased/non lased) and cell attachment to the root end filling material (gutta percha and MTA) were evaluated utilizing immunoflouresence microscopy and SEM. RESULTS: PDL cell attachment was observed on dentin surfaces (control samples) and dentin away from the laser strikes (irradiated samples). PDL cell attachment was observed on MTA but was absent on gutta percha. CONCLUSION: Absence of PDL attachment to laser irradiated dentin could be attributed to morphological surface changes in dentin produced by laser irradiation.

Evaluation of canal cleanliness and smear layer removal after the use of the Quantec-E irrigation system and syringe: a comparative scanning electron microscope study.

OBJECTIVE: The purpose of this study was to evaluate canal cleanliness and smear layer removal after use of the Quantec-E irrigation system and to compare the system with traditional irrigation. STUDY DESIGN: Forty anterior teeth were randomly assigned to 4 groups. Group A consisted of 15 teeth that were instrumented with .12, .10, .08, .06 and .04 tapered rotaries while simultaneously irrigated via the Quantec-E irrigation pump with 12 mL of 5.25% NaOCl, followed by 6 mL EDTA 17% in crown-down fashion, with a final flush with 4 mL 5.25% NaOCl. Group B consisted of 15 teeth that were instrumented with the same instrument sequence, and irrigated with the same volumes via traditional needle and syringe. Group C consisted of 5 teeth that were sectioned and examined under a scanning electron microscope (SEM) without any instrumentation and served as a negative control. Group D consisted of 5 teeth that were instrumented dry, without any irrigation, and served as a positive control. All teeth were sectioned buccolingually and examined with SEM at 700x magnification in the apical, middle, and coronal portions of the canals. Analysis of SEM images was performed by 5 independent examiners using a 4-point scoring system. RESULTS: Irrigation with the Quantec-E irrigation pump resulted in cleaner canal walls, less debris, and more complete removal of the smear layer within the coronal one third, when compared with syringe irrigation. However, no difference was observed in the middle and apical one thirds of the root canal. CONCLUSION: There was no significant difference between the 2 irrigation systems.