Complex Internal Anatomy Research Articles

Root and canal morphology of the maxillary first molar: A micro-computed tomography-focused observation of literature with illustrative cases. Part 2: Internal root morphology

The complexity of root canal morphology can influence cleaning and shaping of the root canal system and, ultimately, treatment outcomes. Undiscovered root canal morphology can greatly reduce the prognosis of endodontic treatment due to the preservation of offending organisms and their by products. The maxillary first molar has been identified as one of the most challenging teeth to treat endodontically due to its complex internal anatomy, the presence of additional and accessory canals and intricate root canal configurations. This paper is the second of two that provide a micro computed tomography (micro-CT)-focused overview of available literature on various aspects of the root and canal morphology of the maxillary first permanent molar. The aim of this paper is to provide an overview of relevant aspects of the internal root morphology in different populations. The content is supported by illustrative micro-CT images and clinical cases or images.

Successful non-surgical endodontic management of type III dens invaginatus by using cone-beam computed tomography: a case report

Dens invaginatus (DI) is a rare malformation of a tooth caused by the invagination of tooth crown before biological mineralization occurs. In DI type III invagination extends beyond the cementum-enamel junction, with the second foramen extending into the periapical tissues or into the periapical area. DI type III may pose real challenges for the clinician, especially when endodontic treatment is required. Objective: The present case report describes the successful non-surgical endodontic management of a tooth with DI type III with the aid of cone-beam computed tomography (CBCT). Case report: A 20-year-old male patient was referred for endodontic evaluation and treatment of the left maxillary lateral incisor (tooth #22), which presented a darker and unusual crown shape. Periapical radiography and CBCT scans revealed the presence of a type III DI, and a larger periapical lesion associated with external root resorption and discontinuous buccal cortical plate Results: The diagnosis of Oehlers type III DI with asymptomatic apical periodontitis was established, and non-surgical endodontic treatment was initiated. After 5 months, a decrease in the periapical lesion and arrest of external resorption was detected. The root canals were then filled, and the tooth restored. At the 3-years follow-up, clinical and imaging assessments revealed successful outcome of the treatment. Conclusion: CBCT is an inestimable tool for non-surgical endodontic management of teeth with complex internal anatomy, such as DI type III with associated large periapical lesion.

Endodontic management of six canalled maxillary first molar: A case report

The clinical management of a maxillary first molar with six root canals is described in this case report having two canals in the mesiobuccal root (MB), two canals in the distobuccal root (DB), and two canals in the palatal root (P). The prevalence of such a complex internal anatomy of teeth is a rare variation. The endodontic management of such deviant canal morphology can be challenging to diagnose and treat. For proper management of such unusual cases, it is essential to have sound knowledge of the intricacies of the anatomy and additional canals. Hence, it is imperative to record such cases in dental literature.

Resolution of Apical Periodontitis-induced Mental Nerve Paresthesia Through Nonsurgical Endodontic Retreatment: A Case Report

Paresthesia is a potential consequence of unsuccessful root canal treatment. Persistent infection resulting in apical periodontitis may enlarge sufficiently to involve the mental neurovascular bundle. The case presented in this report was referred for endodontic evaluation with a chief complaint of discomfort on mastication and persistent numbness of the lower left lip. Clinical and radiographic evaluation revealed incomplete primary endodontic treatment of the left mandibular second premolar with complex internal anatomy. The untreated root canal system resulted in the progression of apical periodontitis involving the left mental neurovascular bundle as confirmed by cone-beam computed tomography imaging. Nonsurgical root canal retreatment was performed over 2 visits. At the 3-year follow-up visit, the paresthesia had resolved with return of normal sensation. Nonsurgical endodontic retreatment may be sufficient to allow healing of large periapical lesions and resolve complications including paresthesia without the need for surgical intervention.

Comparative Evaluation of Smear Layer Removal Efficacy of Neem Leaf Extract, Propolis, and Orange Oil when used as Endodontic Irrigants: An in vitro Scanning Electron Microscopic Study.

In root canal treatment, chemical debridement of the root canal with the help of irrigants is important due to the complex internal anatomy of the teeth. Biomechanical root canal preparation produces a smear layer. It covers the dentinal tubules, which may interfere with the penetration of various irrigants and intracanal medicaments, so the smear layer has to be removed. The potential side effects and certain limitations of chemical irrigants for smear layer removal have led to a shift toward herbal alternatives. The aim of the present study was to evaluate and compare the smear layer removal efficacy of Neem leaf extract, Propolis, and Orange oil as endodontic irrigants using the scanning electron microscope. Ninety samples were taken and then randomly (simple random sampling method) divided into three experimental groups (n = 30) depending upon different endodontic irrigants used: Group 1-Neem leaf extract, Group 2-Orange oil and Group 3-Propolis and smear layer removal evaluation was done under the scanning electron microscope Scanning Electron Microscope (SEM) at all the levels, i.e., coronal, middle, and apical. The collected data were analyzed using the Chi-square test. Group 1 (Neem leaf extract) showed the highest smear layer removal efficacy, which was followed by Group 2 (Orange oil) and the least efficacy of smear layer removal was shown by Group 3 (Propolis) at coronal, middle, and apical levels. Group 1 (Neem leaf extract) performed significantly better in removing the smear layer at coronal, middle, and apical levels as compared to the other two groups.

Endodontic management of multiple roots and root canals in mandibular canine: A case report series

Successful endodontic treatment depends upon the clinician’s precise knowledge and ability to manage complex internal anatomy in order to avoid failure during endodontic treatment. Mandibular canines normally have single root with centrally placed single canal and internal anatomy as simple as could be expected, but there are such canines with a single root with two canals, two roots or fused roots. The occurrence of two canal joining to one for a men may be a rare entity with 4-15% prevalence. Canine is the cornerstone of mouth due to its position and very important as abutment for any type of restoration, so long term success of the restorative depend directly on the quality of endodontic treatment. This article presents a case series of successful endodontic management of mandibular canine with two canals which merge into one canal with one foramina and mandibular canine with two roots and two canals.

Micro-tomographic characterization of the root and canal system morphology of mandibular first premolars in a Chilean population

This study aimed to analyze the root anatomy and root canal system morphology of mandibular first premolars in a Chilean population. 186 teeth were scanned using micro-computed tomography and reconstructed three-dimensionally. The root canal system morphology was classified using both Vertucci’s and Ahmed’s criteria. The radicular grooves were categorized using the ASUDAS system, and the presence of Tomes’ anomalous root was associated with Ahmed’s score. A single root canal was identified in 65.05% of teeth, being configuration type I according to Vertucci’s criteria and code 1MP1 according to Ahmed’s criteria. Radicular grooves were observed in 39.25% of teeth. The ASUDAS scores for radicular grooves were 60.75%, 13.98%, 12.36%, 10.22%, 2.15%, and 0.54%, from grade 0 to grade 5, respectively. The presence of Tomes’ anomalous root was identified only in teeth with multiple root canals, and it was more frequently associated with code 1MP1–2 of Ahmed’s criteria. The root canal system morphology of mandibular first premolars showed a wide range of anatomical variations in the Chilean population. Teeth with multiple root canals had a higher incidence of radicular grooves, which were closely related to more complex internal anatomy. Only teeth with multiple root canals presented Tomes’ anomalous root.

The MB3 canal in maxillary molars: a micro-CT study.

To assess the internal and external morphologies of the mesiobuccal (MB) root of maxillary molars presenting a third root canal (MB3), using micro-computed tomography (micro-CT). Two-hundred and sixty-five extracted maxillary first and second molars with different root configurations were imaged in a micro-CT scanner at 19.6-μm pixel size. Sixteen teeth presenting MB3 canal were selected and evaluated regarding root configuration, minimal dentine thickness 2mm under the furcation area, canal configuration of the MB root, MB3 canal morphology (location, independent or confluent orifice, and anatomy types), and the apical anatomy (aspect ratio, number of accessory canals and foramina, presence of isthmus, and independent MB3 foramen). Overall, a high variability in canal configuration was detected in the MB root. MB3 canal was observed in 10 maxillary first molars and 6 maxillary second molars (n = 16). Minimal dentine thickness related to the MB3 canal at the coronal third was smaller than that of the MB1 canal. A complex internal anatomy comprising 13 different root canal configurations was observed. A high number of independent MB3 orifices at the pulp chamber floor was observed in the first molars (7 out of 10 teeth), while most of the specimens (n = 14) showed a confluent anatomy of the MB3 canal. A varied number of accessory canals and foramina were observed. At the apical third, isthmus could be observed in 6 specimens, while an independent MB3 foramen was present in 37.5% of the MB roots. MB3 canal is a rare anatomical variation present in maxillary first and second molars. Its presence can be associated to a complex internal anatomy of the MB root which includes the presence of isthmuses and multiple accessory canals and foramina at the apical third, but also a thin dentine thickness at the coronal third and a confluent anatomy of the MB3 with the other main canals.

Evaluation of the internal anatomy of paramolar tubercles using cone-beam computed tomography.

To evaluate the internal anatomy of paramolar tubercles (PTs) on molars, determine the existence of root canals in these structures that either communicate with or are isolated from the main root canals of teeth, and analyze the prevalence of root fusion and a C-shaped canal configuration using cone-beam computed tomography (CBCT). Twenty-six molars with PTs from the study group and 664 molars without PTs from the control group were evaluated using CBCT. The locations and sizes of tubercles were noted. The existence of root canals in PTs was detected. All teeth were evaluated according to the presence or absence of root fusion and a C-shaped canal configuration. Statistical analyses were performed with Pearson Chi square and Fisher's exact tests (p < 0.05). Eleven (42.3%) PTs with their own canals communicated with the main root canals of teeth, and 10 of 11 PTs (90.9%) were larger than 4mm in size. No PT possessed its own canal independent from the other canals. Teeth with PTs tended to have more root fusions than teeth without PTs. A statistically significant correlation was observed between PTs and the C-shaped canal configuration (p < 0.01). Maxillary second molars with PTs were the major teeth showing variations in the internal morphology. PTs are an uncommon anatomical variation that is specific to the coronal and radicular morphology. Therefore, clinicians should be aware of its unpredictable and complex internal anatomy, particularly in cases requiring endodontic treatment. CBCT is recommended for teeth with PTs, particularly maxillary second molars, to improve the prognosis of the teeth.

Root CanalIrrigants in Pediatric Dentistry:A Literature Review &amp; Update

Successful root canal treatment is dependent on the removal of microorganisms from he pulp and other anatomical irregularities of the root canal system. However, complete elimination of bacterial contaminants as well as necrotic debris require adjunctive use of root canal irrigants along with mechanical instrumentation. Irrigants can augment mechanical debridement by flushing out debris, dissolving tissue, and disinfecting the root canal system.Chemical debridement is especially needed for primary teeth with complex internal anatomy and zones inaccessible to debridements, such as accessorycanals, ramifications, and dentinal tubules that might be missed by instrumentation.None of the available irrigating solutions alone provides all the ideal requirements. Studies have shown that a combination of two or more irrigating solutions in a specific sequence will help to achieve optimal irrigation

Novel approach to intraoral haemorrhage after mandibular arteriovenous malformation embolization: transoral Onyx embolization of the posterior alveolar vein

AbstractArteriovenous Malformation (AVM) of the mandible is a potentially life‐threatening condition that requires rapid diagnosis and intervention to prevent mortality or permanent morbidity1. While transarterial embolization using liquid embolic material currently serves as the mainstay of treatment, these lesions often feature complex internal anatomy, which may complicate this approach2‐4. This article presents the experiences of two patients who suffered significant intraoral haemorrhage secondary to the posterior alveolar draining vein of a complex mandibular AVM. In both instances, haemostasis was successfully achieved utilizing fluoroscopy‐guided direct puncture of the affected vessel through the oral mucosa, with subsequent Onyx® embolization.

New small-bodied ornithopods (Dinosauria, Neornithischia) from the Early Cretaceous Wonthaggi Formation (Strzelecki Group) of the Australian-Antarctic rift system, with revision ofQantassaurus intrepidusRich and Vickers-Rich, 1999

AbstractThe Flat Rocks locality in the Wonthaggi Formation (Strzelecki Group) of the Gippsland Basin, southeastern Australia, hosts fossils of a late Barremian vertebrate fauna that inhabited the ancient rift between Australia and Antarctica. Known from its dentary,Qantassaurus intrepidusRich and Vickers-Rich, 1999 has been the only dinosaur named from this locality. However, the plethora of vertebrate fossils collected from Flat Rocks suggests that further dinosaurs await discovery. From this locality, we name a new small-bodied ornithopod,Galleonosaurus dorisaen. gen. n. sp. from craniodental remains. Five ornithopodan genera are now named from Victoria.Galleonosaurus dorisaen. gen. n. sp. is known from five maxillae, from which the first description of jaw growth in an Australian dinosaur is provided. The holotype ofGalleonosaurus dorisaen. gen. n. sp. is the most complete dinosaur maxilla known from Victoria. Micro-CT imagery of the holotype reveals the complex internal anatomy of the neurovascular tract and antorbital fossa. We confirm thatQ. intrepidusis uniquely characterized by a deep foreshortened dentary. Two dentaries originally referred toQ. intrepidusare reassigned toQ.?intrepidusand a further maxilla is referred to cf.Atlascopcosaurus loadsiRich and Rich, 1989. A further ornithopod dentary morphotype is identified, more elongate than those ofQ. intrepidusandQ.?intrepidusand with three more tooth positions. This dentary might pertain toGalleonosaurus dorisaen. gen. n. sp. Phylogenetic analysis recovered Cretaceous Victorian and Argentinian nonstyracosternan ornithopods within the exclusively Gondwanan clade Elasmaria. However, the large-bodied taxonMuttaburrasaurus langdoniBartholomai and Molnar, 1981 is hypothesised as a basal iguanodontian with closer affinities to dryomorphans than to rhabdodontids.UUID:http://zoobank.org/4af87bb4-b687-42f3-9622-aa806a6b4116

Comparative Evaluation Of Antibacterial And Layer Removal Efficacy Of Two Different Herbal Irrigants – An In Vitro Study

INTRODUCTION: Irrigation during root canal therapy is especially needed for teeth with complex internal anatomy. Biomechanical preparation of root canal produces "smear layer" which gets embedded with debris and microorganisms. The major side effects of these widely used chemical irrigants such as Sodium hypochlorite for antibacterial efficacy and EDTA for smear layer removal has led to the search of a more biocompatible irrigant.MATERIALS AND METHODS: Azadirachta indica(neem) and Ocimum sanctum(tulsi) extract were used in this study as herbal irrigants to evaluate the above mentioned properties by the q PCR method and SEM analysis.RESULTS: In antimicrobial efficacy, the Mean value of NaOcl showed higher antimicrobial efficacy followed by Neem leaf extract and the lower antimicrobial efficacy was recorded with Tulsi extract. Similarly, the mean smear layer removal by different irrigants at different root levels, EDTA showed the maximum smear layer removal, followed by Neem leaf extract and Tulsi extract showed the least smear layer removal. Hence Tulsi has poor smear layer removal efficacy and comparable antimicrobial efficacy when compared with Neem extractSTATISTICAL ANALYSIS: The collected data were analyzed by one-way analysis of variance to compare the mean of the groups. The post- hoc test (Tukey) was performed to find the interrelationship between different groups for significant difference (P &lt; 0.05; confidence interval 95%).CONCLUSION: From this study, these two herbal irrigants are proved to be safe and effective. It can be concluded that neem leaf extract has a significant antimicrobial efficacy against E. faecalis and significant smear layer removal efficacy compared to 17% EDTA.

Analysis of mandibular second molars with fused roots and shallow radicular grooves by using micro-computed tomography.

Aim:This study aimed to describe the morphological and morphometric aspects of fused mandibular second molars with radicular shallow grooves using micro-computed tomography (CT).Materials and Methods:Eighty-eight mandibular second molars with fused roots were scanned in a micro-CT scanner at a voxel size of 19.6 μm. After reconstruction, only molars without C-shaped roots and presenting shallow radicular grooves were selected. 30 molars were chosen for further analysis. Canal cross-sections were classified according to Fan's modified classification (C1, C2, C3, and C4) and morphometric parameters at the apical region, examination of accessory foramina and tridimensional configuration were evaluated.Results:Three-dimensional reconstructions indicated a higher prevalence of merging type (n = 22). According to Fan's modified classification, the C4 configuration was predominant in the 3 apical mm. Roundness median values revealed a more round-shaped canals at 3 mm (0.72) than at 2 (0.63) and 1 (0.61) mm from the apex. High values of major and minor diameters were observed in the canals of these evaluated sections. In addition, few accessory apical foramina were observed at 1 and 2 mm from the apex. The average distance between last accessory foramina and the anatomic apex was 1.17 mm. A less complex internal anatomy is found when a mandibular second molar presents fused roots with shallow radicular grooves. The merging type canal was frequently observed. Moreover, the C4 configuration was predominant at a point 3 mm from the apex and presented rounded canals, large apical diameters, and few accessory foramina. The cervical and middle thirds presented C3 and C1 canal configurations most frequently.Conclusion:A minor morphological complexity is found when fused mandibular second molars present shallow radicular grooves.

A Rare Case of Type III Dens Invaginatus in a Mandibular Second Premolar and Its Nonsurgical Endodontic Management by Using Cone-beam Computed Tomography: A Case Report

Invaginated teeth present technical difficulties in clinical management because of their abnormal anatomic configuration. Endodontic clinical management of type III dens invaginatus can be greatly enhanced by newer techniques and materials such as cone-beam computed tomography (CBCT), mineral trioxide aggregate, and platelet-rich fibrin. This case report presents a 13-year-old male patient with type III dens invaginatus (DI) in left mandibular second premolar with history of recurrent swelling. Pulp testing revealed no response with the tooth. Dens invaginatus type III with an immature apex and periapical lesion was seen on radiograph. The case was diagnosed as Oehlers type III DI with pulp necrosis and chronic apical abscess. The treatment was planned and performed by using CBCT imaging. CBCT was performed to see the canal anatomy and to know the size of periapical lesion. Root canal treatment was completed in 2 visits. Calcium hydroxide dressing was placed in the first visit. In the second visit MTA was used for apexification in the main canal, and warm vertical compaction technique with gutta-percha was used in the invaginated canal. At the 2-year reevaluation, the patient was asymptomatic, and his tooth had remained functional since the treatment was completed. Radiographic assessment of the tooth showed significant osseous healing of the preoperative lesion. Three-dimensional imaging is a valuable tool for endodontic management of teeth with complex internal anatomy.

Taphonomy of the Ediacaran Podolimirus and associated dipleurozoans from the Vendian of Ukraine

Fossiliferous strata of the late Ediacaran Lomoziv Member of the Mohyliv Formation, once known from now flooded outcrops along the Dniester River, have been recently exposed in a large quarry near the Novodnistrovs’k electric plant dam in Podolia, Ukraine. Finely bedded arkosic sandstone with claystone/siltstone intercalations is locally rich in ‘elephant skin’ surfaces indicating original presence of microbial mats. Imprints of soft-bodied organisms frequently occur on the sole surfaces of the sandstones. There are no signs of early diagenetic cementation with iron sulfides and the fossils are usually strongly compacted, with low relief. Specimens of bilaterally symmetrical latest Precambrian animals newly collected at the quarry offer additional evidence that their bodies had a complex internal anatomy. This relates especially to Podolimirus mirus, previously known from only fragmentary specimens representing only marginal parts of its chambered organ (‘quilt’). It appears that there is a large region of the body in front of the ‘quilt’, with a lobate organ resembling bifurcating anterior structures earlier thought to represent intestinal diverticula in other dickinsoniids. The ‘quilt’ (presumably a dorsal muscular organ) of Podolimirus has a deep medial sinus that may have hosted a cylindrical axial organ analogous to that reported in the dickinsoniids from northern Russia and Australia.

Endodontic Management of a Maxillary Lateral Incisor with 4 Root Canals and a Dens Invaginatus Tract

Dens invaginatus (DI) is associated with complex internal anatomy. This article represents a maxillary lateral incisor with 5 root canals including DI. The treatment was planned and performed using cone-beam computed tomographic (CBCT) imaging. After clinical and radiographic evaluations, tooth #7 was diagnosed with DI and pulp necrosis with symptomatic apical periodontitis. Periapical radiographs of the tooth showed 2 roots and complex internal anatomy. CBCT evaluation revealed tooth #7 had 5 separate canals (4 root canals and 1 DI canal extending through the root to the periodontal ligament), communication between DI and the root canal system, and severe and multiple curvatures of the palatal canals. Root canal treatment was completed in 2 visits. Modified access openings were required to safely treat the dilacerated palatal canals. At the 6-month re-evaluation, the patient reported he had remained asymptomatic and his tooth had remained functional since the treatment was completed. Clinical examination showed tooth #7 had no sensitivity to percussion or palpation, probe depths within normal limits (≤3 mm), and no mobility. Radiographic assessment of the tooth showed significant osseous healing of the preoperative lesion. Three-dimensional imaging is a valuable tool for endodontic management of teeth with complex internal anatomy. Three-dimensional imaging is recommended for evaluating and treatment planning cases with DI.

Endodontic Treatment of Maxillary Premolar with Three Root Canals Using Optical Microscope and NiTi Rotatory Files System

The aim of the study was to report a clinical case of endodontic treatment of a maxillary first premolar with three root canals using an optical microscope and rotary instrumentation technique. The main complaint of the patient, a 16-year-old girl, was pain in tooth 14. After clinical and radiographic examination, irreversible pulpitis was diagnosed. An alteration in the middle third of the pulp chamber radiographically observed suggested the presence of three root canals. Pulp chamber access and initial catheterization using size number 10 K-files were performed. The optical microscope and radiographic examination were used to confirm the presence of three root canals. PathFiles #13, #16, and #19 were used to perform catheterization and ProTaper files S1 and S2 for cervical preparation. Apical preparation was performed using F1 file in the buccal canals and F2 in the palatal canal up to the working length. The root canals were filled with Endofill sealer by thermal compaction technique using McSpadden #50. The case has been receiving follow-up for 12 months and no painful symptomatology or periapical lesions have been found. The use of technological tools was able to assist the endodontic treatment of teeth with complex internal anatomy, such as three-canal premolars.

Early oligochaete science, from Aristotle to Francesco Redi

The paper reviews knowledge on earthworms from early classical times to the end of the seventeenth century. The Aristotelian view that these “imperfect” animals developed spontaneously from mud and lacked internal organs except the gut was not challenged until the late Renaissance but, by the end of the 1600s, it was overthrown. Aldrovandi and Mouffet presented field observations of sexual reproduction and specific habitat requirements. Willis demonstrated the complex internal anatomy of an earthworm. Finally Redi, based on numberless dissections, showed the existence of variations on that basic anatomical plan, which anyway remained distinct from that of parasitic worms. Through a series of controlled laboratory tests, Redi also proved that earthworms have a physiology of their own and are most sensible to water loss. In those same years, Swammerdam investigated earthworm cocoons nursing them in his room, and Tyson discovered earthworms’ hermaphroditism. Two significant interpretations of earthworm's locomotion, by Fabrici ab Aquapendente and Borelli, also belong to this period, but were both short-lived in their influence. An awareness of the ecological role of earthworms in pedogenesis and soil fertility did not emerge until the late eighteenth century.

Management of Dens Invaginatus Type I and Open Apex: Report of Three Cases

Introduction Dens invaginatus is a critical condition for endodontic treatment once it frequently presents a complex internal anatomy and might be associated with incomplete root and apical development. Methods Three cases of dens invaginatus with open apex in maxillary lateral incisors are presented. In the first case, apexification with calcium hydroxide pastes was performed. In the second case, initial treatment was carried out, but the patient missed follow-up appointments for 15 months. In the third case, periradicular surgery was done as a result of the persistence of exudates and incomplete root canal development after conservative endodontic treatment. Oehlers' type I dens invaginatus was also present in the opposite maxillary lateral incisor in 2 patients, but no treatment was required. Results At subsequent follow-up, the periradicular region was completely healed, and postoperative radiographs revealed good bone healing in all patients. Patient #2 had an increase in root length, and after 38 months the apical third was completely calcified. Conclusions A careful clinical and radiographic examination should be conducted to identify dens invaginatus associated with incomplete root development and open apexes. Adequate periradicular healing was observed after the infection, and the anatomical features in the root canal system were accessed. Because a long period is required to determine the clinical outcome, patient compliance must be encouraged.