Surgical management of a lateral lesion refractory to root canal retreatment caused by an extraradicular calculus. A case report.

This article describes the management of a root canal-treated maxillary central incisor displaying a radiographic lateral radiolucency and a sinus tract that persisted irrespective of root canal retreatment following high standards. Endodontic microsurgery was indicated and curettage of the pathologic tissue revealed a calculus-like material attached to the outer root surface around the exit of a large lateral canal. A non-conventional approach was chosen: No root-end resection was conducted. Instead, the calculus was removed and the apical surface was scaled and smoothed, conserving the apical structure. Retrocavities were prepared in both lateral and apical foramens and filled with a bioceramic material. Follow-up examination showed optimal soft tissue healing. One-year follow-up of radiographs revealed healing of the lateral lesion. The lesion was diagnosed as a cyst, with an infected lumen. An exuberant calculus-like material attached to the external root surface was the most likely cause of the recalcitrant lateral periradicular lesion.

Generalized pulp canal obliteration in a patient on long-term glucocorticoids: a case report and literature review.

BACKGROUND: The calcification of the tooth pulp is a pathological condition that occurs in response to various factors. A uncommon haematological condition known as paroxysmal nocturnal haemoglobinuria (PNH) is characterized by bouts of haemolysis, and it requires long-term use of glucocorticoids (GCs). CASE PRESENTATION: A female patient who was diagnosed with PNH and had a history of long-term use of GCs came to our department for root canal therapy (RCT) for teeth 25, 26, and 27. The radiographs showed generalized pulp canal obliteration (PCO) in most of the patients. None of these teeth (25, 26, or 27) were sensitive to percussion, and they did not respond to thermal or electrical sensitivity tests. A diagnose of pulp necrosis was made for these teeth. RCT was carried out with the help of an oral microscope, and then a prosthodontic procedure was created for the teeth. CONCLUSIONS: Based on the patient's long history use of GCs and a series of related studies, we conclude that the long-term usage of GCs contributes significantly to the onset of PCO.

Morphological, histological, and chemical analysis of first permanent molars with molar incisor malformation.

PURPOSE: Molar incisor malformation (MIM) is a dental anomaly rendering first permanent molar pulps inflamed/necrotic at a young age. It often affects permanent incisors, primary second molars and less frequently other teeth. The purpose of this study was to investigate the anatomy and histology of MIM in seeking insight into its pathogenesis. METHODS: Five MIM first permanent molars were examined with micro-computed tomography (micro-CT) for 3D morphology, with scanning electron microscopy for microanatomy, with energy-dispersive X-ray spectrometer (EDS) for chemical composition and for histology with optical microscopy. Composition differences were statistically determined using one-way ANOVA. RESULTS: Micro-CT confirmed dentin abnormalities in the middle and cervical third of the crown in the form of the radiodense 'cervical mineralized diaphragm' (CMD). This was peripherally intertwined with enamel fjords and projections severely disrupting the integrity of pulp chamber and its continuity with root canals. EDS showed increased Ca in CMD compared to dentin. The histological examination revealed anomalous osteodentin-like hard tissue with denticles in the CMD. CONCLUSION: An interconnection of anomalous cervical enamel with crown CMD dentin preceded to the severe pulp chamber and root dysplasias in MIM molar teeth.

Treatment of type III dens invaginatus in bilateral immature mandibular central incisors: a case report.

BACKGROUND: Dens invaginatus (DI) is a developmental anomaly, Oehlers Type III DI is the most complex type and early diagnosis and treatment is complicated and challenging. This report presents a rare case of a type IIIb DI associated with a periapical lesion in bilateral immature permanent mandibular central incisors. CASE PRESENTATION: An eight-year-old boy referred to our clinic manifesting with pain along with swelling in the mandibular incisors for the past one month. Radiographic examination showed periapical radiolucency exhibiting a scantly defined border, as well as an invagination which had a central invaginated canal extending from the pulp chamber throughout the apical foramen in both mandibular central incisors. We performed two different treatment procedures on the basis of the condition of the main pulp of the mandibular central incisors. in which only the invagination root canal was treated in the right mandibular central incisor, while the invagination and main root canals were treated in the left mandibular central incisor. During the 18-month follow-up period, the teeth were clinically asymptomatic. Imaging examinations indicated complete healing of the periapical lesion and revealed that the wall of the root canal was thickened and the open apex was closed. CONCLUSION: For young permanent teeth with type III Dens invaginatus, it is particularly important to keep pulp vitality, which could maintain root development and allow a good long-term prognosis.

Pulp chamber features, prevalence of abscesses, disease severity, and PHEX mutation in X-linked hypophosphatemic rickets.

INTRODUCTION: Rickets, growth failure, and recurrent periapical abscesses with fistulae are main signs in patients with X-linked hypophosphatemic rickets (XLH). Prevalence of abscesses, pulp chamber features, biochemical findings, disease severity, and PHEX gene mutation were examined. MATERIALS AND METHODS: Pulp chambers size, shape, and morphology were assessed by orthopantomography in XLH patients (n = 24, age 5.8 ± 1.6 years) and in sex and age-matched healthy controls (n = 23, age 6.2 ± 1.4 years). XLH patients received conventional treatment (3.5 ± 1.9 years). Pulp chamber features were assessed in teeth of primary dentition and in the permanent left mandibular first molar and compared with those of controls. Rickets severity score was assessed at wrist, knee, and ankle. RESULTS: The mean pulp chamber area/tooth area ratio, mean pulp chamber height/pulp chamber width ratio, and prominence of pulp horns into the tooth crown in primary and secondary molars were significantly higher in patients than in controls and in patients suffered abscesses than in patients without abscesses. Sixteen patients (67%) had a history of abscesses; incisors were affected more than canines and molars. Severity of rickets and mean serum parathyroid hormone (PTH) levels were significantly higher, and mean serum 1,25-dihydroxyvitamin D [1,25(OH)2D] levels significantly lower in patients suffered abscesses than in patients without abscesses. PHEX gene mutations were not correlated with dental phenotype and disease severity. CONCLUSION: Enlarged pulp chambers with altered shape and morphology affected the majority of XLH patients predisposing to recurrent periapical abscesses with fistulae. Dental phenotype was associated with severity of rickets, high serum PTH, and low serum 1,25(OH)2D levels.

Assessment of the Antibacterial Effects of Bismuth Nanoparticles against Enterococcus faecalis.

INTRODUCTION: Enterococcus faecalis (E. faecalis) is the most important species in dentistry and plays a significant role in the etiology of persistent apical lesions after root canal treatment. Up to date, the intracanal application of 2% chlorhexidine for 7 days is the best way to eliminate E. faecalis. However, due to the ability of this bacterium to persist and survive in harsh environments, many studies have been directed towards finding an alternative strategy for prevention or eradication of it. This study was conducted to investigate the effect of bismuth nanoparticles on E. faecalis, as an etiologic factor in recurrent root canal infections. METHODS: Forty patients, referred to Endodontic Ward of Shiraz University of Medical Science for endodontic pretreatment, provided root canal samples. First, all samples were transferred in Enterococcosel broth and incubated. Then, samples which showed growth were plated on blood agar plates and incubated for further PCR procedure. Nanoparticle powder was dissolved in high-purity water, and the final concentration of bismuth nanoparticles (BiNPs) was measured by the spectrophotometer. Minimum inhibitory concentration (MIC) of BiNPs against E. faecalis was determined by microbroth dilution method according to methods for antimicrobial susceptibility tests. Also, bactericidal assays were conducted in Mueller-Hinton broth medium and reported as the concentration of BiNPs that reduced the viable bacterial count by 99.9%. RESULTS: Of all samples, 77.5% revealed the presence of E. faecalis by PCR. Also, E. faecalis growth inhibition was observed at concentrations ranging from 0.625 µg/ml to 20 µg/ml (geometric mean: 2.337 µg/ml), and the MBC values were between 1.25 µg/ml and 40 µg/ml (geometric mean: 4.781 µg/ml), which in comparison with chlorhexidine, these values were about one-eighth of chlorhexidine. CONCLUSION: The experimental data suggest that bismuth nanoparticles could be an interesting alternative to combat E. faecalis, which, in view of the advantages mentioned for bismuth nanoparticle like inhibiting Streptococcus mutans biofilm formation and higher antibacterial activity compared to chlorhexidine, can be suggested to be used in different fields of dentistry.

Preoperative Estimation of Endodontic Working Length with Cone-Beam Computed Tomography and Standardized Paralleling Technique in comparison to Its Real Length.

An accurate estimation of the working canal length is essential for successful root canal treatment. This study is aimed at investigating the diagnostic accuracy of root canal length estimation on cone-beam computed tomography (CBCT) scans and digital paralleling radiographs (PAs), using the real canal length as a gold standard, and at evaluating the influence of canal curvature on this estimation. Sixty extracted human premolar teeth were selected for this study. Root canal length measurement was performed on CBCT scans (NewTom, Giano, Verona, Italy) and digital paralleling radiography (EzRay Air W; Vatech, Korea). The real working length was established by subtracting 0.5 mm from the actual canal length. No significant difference was found between CBCT and digital paralleling radiography. There was a tendency for underestimation of the root canal length measured on the CBCT images in 52 (86.7%) of the examined teeth and overestimation in 5 teeth (8.3%). All the digital radiographs slightly overestimated the real canal length. The analysis revealed a strong correlation between the estimation from moderate to severe curvature for digital radiography and CBCT images. Preoperative working length estimation can be made closest to its real clinical canal length on the standardized paralleling technique, using a long (16-inch) target-receptor distance.

Radiographic and Clinical Findings of Single-Visit Root Canal Treatments with Apical Enlargement in Necrotic Teeth: A Retrospective Cohort Study.

This study evaluated the long-term clinical outcomes of single-visit root canal treatments with apical enlargement on patients with necrotic pulp tissue retrospectively. A total of 137 teeth with necrotic pulp tissue which underwent single-visit root canal treatments were included. The root canals were shaped up until the apical constriction, which was determined by an apex locator. The outcomes were evaluated by two independent and calibrated endodontists clinically and radiographically. Teeth were dichotomized into healed (PAI ≤ 2, no signs or symptoms) and nonhealed (PAI > 2, with/without signs or symptoms) groups. Each patients' preoperative PAI and lesion size were recorded to evaluate the preoperative periapical status as well as several other prognostic factors. Statistical analyses were performed (p = 0.05) on ninety teeth. The mean observation time was 60 months. Out of ninety teeth, 87 (96.7%) were healed and 3 (3.3%) were nonhealed. No correlations were found between the prognostic factors and the outcomes (p > 0.05). Cohen's kappa and Gwet's agreement coefficient scores between the preoperative PAI scores and preoperative lesion sizes showed good agreements, with values of 0.834 and 0.898, respectively. Apical enlargement is a viable treatment option for single-visit root canal treatments.

Assessment of the functional efficacy of root canal treatment with high-frequency waves in rats.

The purpose of this study was to develop a high-frequency wave therapy model in rats and to investigate the influence of high-frequency waves on root canal treatment, which may provide a novel strategy for treating apical periodontitis. Root canal treatments with and without high-frequency wave irradiation were performed on the mandibular first molars of 10-week-old male Wistar rats. The mesial roots were evaluated radiologically, bacteriologically, and immunohistochemically. At 3 weeks after root canal treatment, lesion volume had decreased significantly more in the irradiated group than in the non-irradiated group, indicating successful development of the high-frequency therapy model. The use of high-frequency waves provided no additional bactericidal effect after root canal treatment. However, high-frequency wave irradiation was found to promote healing of periapical lesions on the host side through increased expression of fibroblast growth factor 2 and transforming growth factor-ß1 and could therefore be useful as an adjuvant nonsurgical treatment for apical periodontitis.

Efficacy of Endoactivator, CanalBrush, and passive ultrasonic irrigation in the removal of calcium hydroxide paste with iodoform and p-chlorophenol from root canals.

AIMS: We evaluated and compared EndoActivator, CanalBrush, and passive ultrasonic irrigation (PUI) in the removal of calcium hydroxide and calcium hydroxide with iodoform and p-chlorophenol paste (Calcipast Forte) from artificial standardized grooves in the apical third of root canals. MATERIALS AND METHODS: A total of 34 mandibular premolars were prepared and then split longitudinally. A standardized groove was prepared in the apical part of both segments. The grooves were filled with either calcium hydroxide or Calcipast Forte, and the segments were reassembled. CanalBrush, EndoActivator, or PUI were used. The amount of remaining medicament was evaluated using a four-grade scoring system. RESULTS: None of the irrigation methods could completely remove the pastes from the grooves. More Calcipast Forte paste was detected compared with calcium hydroxide (P < 0.01). PUI was the least effective method in removing Calcipast Forte. CONCLUSIONS: It was more difficult to remove Calcipast Forte than a water-based calcium hydroxide paste.

Root canal contamination or exposure to lipopolysaccharide differentially modulate prostaglandin E 2 and leukotriene B 4 signaling in apical periodontitis.

Purpose To evaluate the kinetics of apical periodontitis development in vivo , induced either by contamination of the root canals by microorganisms from the oral cavity or by inoculation of bacterial lipopolysaccharide (LPS) and the regulation of major enzymes and receptors involved in the arachidonic acid metabolism. Methodology Apical periodontitis was induced in C57BL6 mice (n=96), by root canal exposure to oral cavity (n=48 teeth) or inoculation of LPS (10 µL of a suspension of 0.1 µg/µL) from E. coli into the root canals (n= 48 teeth). Healthy teeth were used as control (n=48 teeth). After 7, 14, 21 and 28 days the animals were euthanized and tissues removed for histopathological and qRT-PCR analyses. Histological analysis data were analyzed using two-way ANOVA followed by Sidak's test, and qRT-PCR data using two-way ANOVA followed by Tukey's test (α=0.05). Results Contamination by microorganisms led to the development of apical periodontitis, characterized by the recruitment of inflammatory cells and bone tissue resorption, whereas inoculation of LPS induced inflammatory cells recruitment without bone resorption. Both stimuli induced mRNA expression for cyclooxygenase-2 and 5-lipoxygenase enzymes. Expression of prostaglandin E 2 and leukotriene B 4 cell surface receptors were more stimulated by LPS. Regarding nuclear peroxisome proliferator-activated receptors (PPAR), oral contamination induced the synthesis of mRNA for PPARδ, differently from inoculation of LPS, that induced PPARα and PPARγ expression. Conclusions Contamination of the root canals by microorganisms from oral cavity induced the development of apical periodontitis differently than by inoculation with LPS, characterized by less bone loss than the first model. Regardless of the model used, it was found a local increase in the synthesis of mRNA for the enzymes 5-lipoxygenase and cyclooxygenase-2 of the arachidonic acid metabolism, as well as in the surface and nuclear receptors for the lipid mediators prostaglandin E2 and leukotriene B4.

Influence of cervical preflaring and root canal preparation on the fracture resistance of endodontically treated teeth.

BACKGROUND: Evaluate the fracture resistance of endodontically treated teeth after cervical preflaring and root canal preparation and to assess the volume of the root canal and the amount of remaining root dentin before and after cervical preflaring. METHODS: Forty-four mandibular incisors were selected using micro-CT scanning and distributed into 4 groups (n = 11) according to the instrument used for cervical preflaring: control group - no cervical preflaring; Gates Glidden - burs size #2 and #3; WXN - 25.07 Navigator instrument; and Easy - 25.08 ProDesign S instrument. Coronal opening was performed, and the canals were prepared with Wave One Gold Primary and filled with an epoxy-resin based sealer and gutta-percha cones. Micro-CT scans were performed before and after root canal instrumentation. All images were reconstructed and assessed for the thickness of mesial and distal root dentin at 3 mm and 5 mm from the cement -enamel junction and for the volume of cervical portion of the canal after preparation. Fracture resistance test was performed applying compressive loads at a crosshead speed of 0.5 mm/min, applied on the palatal aspect of specimens at 135° along the long axis of the tooth. The data were analyzed using ANOVA and Tukey's test (P = .05). RESULTS: Cervical preflaring and canal preparation reduced the dentin thickness (P < .05) and increased the canal volume (P < .05) in all groups at 3 mm an 5 mm. Cervical preflaring with Gates Gliden burs reduced the fracture resistance of endodontically treated teeth (P < .05). CONCLUSIONS: All instruments reduced the dentin thickness and increased the canal volume in the cervical at 3 mm and 5 mm. Gates Glidden reduced fracture resistance of mandibular incisors submitted to cervical preflaring, whereas NiTi instruments did not. CLINICAL RELEVANCE: Cervical preflaring assumes particular importance previously to the root canal preparation because it minimizes the occurrence of operative accidents, and permits more accurate determination of working length and the apical diameter.

Treatment of peri-invagination lesion and vitality preservation in an immature type III dens invaginatus: a case report.

BACKGROUND: To report a case of type III dens invaginatus associated with peri-invagination periodontitis in an immature permanent mandibular central incisor with open apex, in which only the invagination area was treated and vitality was preserved. CASE PRESENTATION: A 9-year-old boy was referred complaining of pain in the mandibular left central incisor. After radiographic examination, an invagination into the pulp chamber of the tooth associated with periapical radiolucency was detected. Endodontic access was performed and the orifice was identified under a dental operating microscope. The invagination area was chemo-mechanically cleaned. After 1 week, the invagination was obturated with mineral trioxide aggregate. During the 2-year follow up period, the tooth was asymptomatic. Radiographic examination revealed significant progression of periapical healing and root development in the main root canal of the tooth. CONCLUSION: Non-surgical root canal treatment of the invagination may preserve pulp vitality, and continuous root development of the tooth.

Comparison of postoperative pain after foraminal enlargement of necrotic teeth using continuous rotary system and reciprocating instrument: A randomized clinical trial.

OBJECTIVES: This single-blind, randomized clinical trial (RCT) aimed to compare the duration, intensity, and incidence of postoperative pain after foraminal enlargement (FE) with continuous rotary systems and reciprocating instruments. MATERIALS AND METHODS: Sixty qualified patients were randomly divided into the following two groups: the ProTaper Next group and the WaveOne group. Participants were selected from patients who had both asymptomatic necrosis and asymptomatic apical periodontitis with a single root canal. Endodontic treatment was performed in one visit, and the patients were asked to record their pain severity and analgesic consumption during a 7-day follow-up period using a visual analog scale (VAS). The data were analyzed using the Mann-Whitney U-test and Chi-square test (P < 0.05). RESULTS: A significant difference was observed between the two groups during the first two days of follow-up (P < 0.05). Pain experience was higher in FEs that had been created by reciprocating instruments than by continuous rotary systems. There were no significant differences in VAS pain scores over the other days (P > 0.05). None of the patients had severe postoperative pain during the follow-up period. No significant differences were observed in the prevalence of analgesic consumption between either group (P > 0.05). CONCLUSIONS: This RCT indicates that in the 2-day follow-up period after endodontic treatment, FEs created by reciprocated instruments associated more postoperative pain than continuous rotary systems.

Effect of different laser-assisted irrigation activation techniques on apical debris extrusion.

Objective: The aim of this study was to compare apical debris extrusion when neodymium-doped yttrium aluminium garnet (Nd:YAG) lasers, erbium-doped yttrium aluminium garnet (Er:YAG) or photon-induced photoacoustic streaming (PIPS) are used for irrigation activation.Materials and methods: A total of 60 extracted human mandibular premolar teeth have similar dimensions were included and the samples were split into four groups according to the irrigation technique (n = 15): conventional needle irrigation, PIPS, Er:YAG and Nd:YAG. ProTaper Universal system up to F4 was used for root canal instrumentation. Bidistilled water was used as an irrigation solution during instrumentation and irrigation activation. Apically extruded debris was collected into preweighed Eppendorf tubes during instrumentation and irrigation activation procedures. The tubes were then kept in an incubator at 70 °C for 5 days. The initial weight of the tube was subtracted from the final weight and the result was recorded as the weight of dry extruded debris. The data were evaluated statistically using a one-way ANOVA test followed by least significant difference post hoc test (p < .05).Results: Conventional needle irrigation caused significantly less debris extrusion than laser-assisted irrigation activation groups (p < .05). Laser-assisted irrigation activation groups caused statistically similar debris extrusion (p > .05).Conclusion: Laser-assisted irrigation activation techniques caused more debris extrusion when compared to conventional needle irrigation.

Conservative esthetic management of post orthodontic treatment discolored tooth with calcified canal: a case report.

A case of pulp canal obliteration (PCO) two years after the completion of orthodontic treatment is presented. Post orthodontic treatment PCO is a rare finding. A 23 years old female presented with the discoloration of clinical crown of maxillary right central incisor. Radiographic examination revealed the calcified canal and diffused periapical radiolucency. Vitality tests were negative. A decision was made to do root canal treatment followed by the walking bleaching. After the successful completion of the root canal treatment the internal bleaching was performed. The discolored tooth showed significant improvement in color. Internal bleaching is a viable conservative treatment for improving esthetics in single non vital discolored tooth.

Stereomicroscopic and Microscopic Study of Dental Structural Aspects Derived from Iatrogenic and Pathological Processes Suffered by a Second Mandibular Premolar - A Case Study.

Microscopic studies performed on extracted human teeth after their preparation in advance is helpful in a relatively good reestablishment of the treatment steps that have been applied to these teeth, as well as an evaluation of the quality of such treatments. Therefore, we have used stereo- and optical microscopy, highlighting aspects of external morphology, as well as root canal space of an extracted mandibular second premolar, subjected to prosthetic and endodontic treatment. In order to verify some technical errors that might occur during the endodontic and restorative treatment, we tried to appreciate the quality of the root canal filling and cervical defect and access cavity restoration of an extracted premolar #45.Without having the data from clinical records, we concluded that the method used for root canal filling was the warm lateral condensation technic; we also appreciated the quality of the fusion of the gutta-percha cones used, so the introduction of heated spreaders only in the central part of the bunch of cones makes it possible to clearly detect the boundaries between these cones towards the outside of the filling.

Root canal contamination or exposure to lipopolysaccharide differentially modulate prostaglandin E 2 and leukotriene B 4 signaling in apical periodontitis

Abstract Purpose To evaluate the kinetics of apical periodontitis development in vivo , induced either by contamination of the root canals by microorganisms from the oral cavity or by inoculation of bacterial lipopolysaccharide (LPS) and the regulation of major enzymes and receptors involved in the arachidonic acid metabolism. Methodology Apical periodontitis was induced in C57BL6 mice (n=96), by root canal exposure to oral cavity (n=48 teeth) or inoculation of LPS (10 µL of a suspension of 0.1 µg/µL) from E. coli into the root canals (n= 48 teeth). Healthy teeth were used as control (n=48 teeth). After 7, 14, 21 and 28 days the animals were euthanized and tissues removed for histopathological and qRT-PCR analyses. Histological analysis data were analyzed using two-way ANOVA followed by Sidak's test, and qRT-PCR data using two-way ANOVA followed by Tukey's test (α=0.05). Results Contamination by microorganisms led to the development of apical periodontitis, characterized by the recruitment of inflammatory cells and bone tissue resorption, whereas inoculation of LPS induced inflammatory cells recruitment without bone resorption. Both stimuli induced mRNA expression for cyclooxygenase-2 and 5-lipoxygenase enzymes. Expression of prostaglandin E 2 and leukotriene B 4 cell surface receptors were more stimulated by LPS. Regarding nuclear peroxisome proliferator-activated receptors (PPAR), oral contamination induced the synthesis of mRNA for PPARδ, differently from inoculation of LPS, that induced PPARα and PPARγ expression. Conclusions Contamination of the root canals by microorganisms from oral cavity induced the development of apical periodontitis differently than by inoculation with LPS, characterized by less bone loss than the first model. Regardless of the model used, it was found a local increase in the synthesis of mRNA for the enzymes 5-lipoxygenase and cyclooxygenase-2 of the arachidonic acid metabolism, as well as in the surface and nuclear receptors for the lipid mediators prostaglandin E2 and leukotriene B4.

Guía de práctica médica patología pulpar y periapical en dentición permanente / Pulp and periapical pathology medical practice guide in permanent dentition

Generar recomendaciones basadas en la mejor evidencia disponible acerca del manejo de personas con diagnóstico de patologías pulpares o periapicales en dentición permanente. Personas con diagnóstico de patología pulpar o periapical en diente permanente que reciben atención en el nivel primario de salud en el sector público y privado de salud.