Two-rooted Teeth Research Articles

The Relationship Between Crown Shape and Root Canal Morphology of Maxillary Second Molars in an Iraqi Sub-population Using Cone Beam Computed Tomography (CBCT)

Objective: This study aimed to look into how crown shape affected the architecture of the root canals.
 Methods: Nine hundred and fifty-four CBCT scans of maxillary second molars were evaluated. The relation between the crown shapeand sex, root number, and root canals was determined. The frequency of the second canal in the mesiobuccal root (MB2), its agerelation, and the symmetry of the concurrence of anatomical variations in contralateral molars were analyzed. The chi-square test wasused for the analysis of the outcomes. It was deemed significant at P< 0.05.
 Results: Overall, rhomboidal-shaped crowns comprised 60.1% of all crowns, while heart-shaped crowns made up 39.9%. Three-rootedteeth were the most common (74.5%), followed by two-rooted teeth (11.9%) and one-rooted teeth (8.5%), while four-rooted teeth madeup only 5% of all samples. The most prevalent result in terms of the canal number was three canals (67%), followed by four canals(24.8%), two canals (7.3%), one canal (0.6%), and five canals (0.4%). Males were less likely to have crowns with a heart-shapedstructure than females. The rhomboidal crown (22%) had a higher occurrence of MB2 canals when compared to the heart-shaped crown (2.8%).
 Conclusions: Given the constraints of this research, it would seem that the rhomboid form of the upper second molar crown is moreprevalent, with a greater tendency to have three and four roots and the presence of MB2 than the heart-shaped form.

Three-dimensional visualization of Hertwig's epithelial root sheath during tooth root development with the miniTESOS tissue clearing method.

Hertwig's epithelial root sheath (HERS) acts as a signaling center that regulates the size, shape, and number of tooth roots. Therefore, understanding the anatomical changes in HERS during development is crucial for investigating its effect on root formation. However, the three-dimensional morphology of HERS and its changes during tooth root development remain largely unknown due to the limitations of traditional histological techniques. We developed an improved tissue clearing method for mouse embryonic and early postnatal mandibles, designated as a mini Transparent Embedding Solvent System (miniTESOS), based on the Transparent Embedding Solvent System (TESOS). We applied this method to the K14-Cre;Ai14 mouse line to systematically investigate the spatiotemporal dynamics of HERS at the cellular level during the development of the roots of mandibular first molars (MM1) and mandibular second molars (MM2). Additionally, using MM1 as a model, we quantitatively investigated the spatiotemporal changes in HERS in the root bifurcation region during the development of two-rooted teeth. In the early stages of root development, differences in growth rates and developmental patterns between MM1 and MM2 were observed in the mesiodistal and buccolingual directions, from the initiation to the fusion of buccal and lingual HERS. In the elongation stage of two-rooted teeth, continuous HERS was found exclusively at the leading edge of the root, gradually decreasing in length as the root extended. In the root bifurcation area, HERS undergoes four developmental stages: initiation, elongation, contact, and complete fragmentation, each characterized by specific morphological features. This study improves the understanding of the alterations in HERS during root development and summarizes its developmental pattern in the root bifurcation region. The miniTESOS tissue clearing method provides a new strategy to investigate tooth development.

Hemisectomy: A ray of hope for a periodontally and cariously involved mandibular first molar

Hemisectomy refers to the removal of a root with the associated crown portion of two-rooted teeth, commonly the mandibular molars, due to its high predilection for extraction due to dental caries and periodontal disease. Hemisectomy of a mandibular molar may be an appropriate treatment option when caries or resorption is limited to one root, while the other is healthy; thus, preserving the tooth structure, and alveolar bone and promoting affordability over other treatment possibilities. This article entails a procedure for Hemisectomy in a mandibular first molar and its ensuing restoration with a fixed prosthesis. Hemisectomy and prosthetic reintegration yielded an acceptable result.

Is a non-radiological-assisted method valid for establishing crown-root relationships in an orthodontic set-up incorporating the roots? A retrospective study

This study aimed to obtain information on the relationship between crown and root in terms of morphology - dimensions and crown-root angles -to be used for orthodontic set-ups without the use of radiological examinations. All the good quality CBCTs of patients obeying the eligibility criteria, from 2000 to 2015, were analysed. All teeth were analysed except for third molars. Six variables were evaluated: crown (CL) and root length (RL), crown width (CW), root width (RW), crown-root angles in both the frontal (CR-frontal) and sagittal plane (CR-sagittal). All teeth were divided into 3 groups according to number of root (single, two, three-rooted). The measurements were assessed with the Invivo professional software and then, subjected to correlation matrices and linear regression statistical analysis in order to find any significant correlations between crown and root measurements (α≤0.05). Seventy-three out of 247 good quality CBCTs were assessed. Correlation matrices statistical analysis showed linear correlations for some variables investigated, especially for CW/RW pairing in all subgroups (r=0.81, r=0.70 and r=0.58 respectively for single-, two- and three-rooted) and CL/RL in the single-rooted subgroup (r=0.29). Subsequent linear regression analysis allowed to obtain information about roots starting from crown measurements by means of equations [RW=0.76+(0.73×CW) and RL=10.94+(0.25×CL) for single-rooted teeth; RL=1.11+(0.73×CW) and RW=0.99+(0.76×CW), respectively for single- and two-rooted teeth]. No linear correlation was found between crown measurements and C-R angular values. It is possible to obtain root information starting from some crown measurements but these do not fulfil the need of minimal information to guarantee a perfect root position starting from that of crown.

Prevalence of two-rooted and one-rooted mandibular canines with two root canals in Poland, assessed using CBCT: A preliminary study.

The normal anatomy of mandibular canines presents with 1 root and 1 root canal. Two roots are found in approx. 2% of cases, and a bilateral configuration is even rarer. Canines with 2 root canals are found in around 15% of cases. Cone-beam computed tomography (CBCT) enables the detailed visualization of the teeth. The present study aimed to evaluate the prevalence of two-rooted mandibular canines and one-rooted mandibular canines with 2 root canals in a Polish population by using CBCT. A total of 300 consecutive CBCT scans, taken for different clinical indications, were examined to assess permanent mandibular canine anatomy. The study group included 182 females and 118 males aged 12-86 years (mean age: 31.7 years). Among 600 cases, 27 two-rooted teeth were found (4.5%), and there were only 6 cases of onerooted mandibular canines with 2 root canals (1.0%). Six cases of two-rooted canines had this configuration bilaterally, all in females. Five cases of canines with 2 root canals were found on the left side (83.3%). The predominance of the occurrence of two-rooted canines in females (81.5%) was strongly emphasized. The prevalence of two-rooted mandibular canines in a Polish population, evaluated by means of CBCT, was higher, while the presence of 2 root canals was lower than in recent literature reports. There was no side predilection of two-rooted mandibular canines, although their occurrence was higher in females.

Perception of the clinical endodontic practice of Dentistry graduates in their first years in the job market in southern Brazil

Introduction: Knowledge about the clinical endodontic practices of dental school graduates in the first years of their professional life may contribute to the discussions about Dentistry teaching. Methods: An online questionnaire with seven open and closed questions hosted on the Google forms platform was applied to dentists trained in the first half of 2019 in a School of Dentistry in southern Brazil. The questionnaire is structured to analyze how clinical Endodontics has been practiced in the labor market. The data collected in the questionnaires were transferred to an Excel® spreadsheet and analyzed as absolute and relative frequencies for closed questions and descriptions for open questions. Results: Molars and two-rooted teeth are the dental groups most frequently treated endodontically (64.3% and 35.7%). Both retreatment and conservative treatment of the pulp corresponded to up to 25% of all procedures in the graduates’ clinical practice. The endodontic protocol learned in their dental school was used by 64.3% of the graduates who provided endodontic treatments, and 42.9% reported the occurrence of at least one accident. The difficulty in access reported by the participants suggests that more training should be provided for this operative stage. Conclusions: After two years in the job market and having faced the initial difficulties existing in any profession, more than half of the graduates still performed endodontics in their dental clinical practice and used the same protocols learned in dental school.

Economic analysis of the different endodontic instrumentation techniques used in the Unified Health System

BackgroundTo assess the financial impact of incorporating a new (reciprocal) technology into endodontic treatments in the public health system (SUS).MethodsThis was a economic evaluation study (comparing the 3 different endodontic instrumentation techniques—manual, rotary and reciprocating), allocative efficiency analysis to optimize existing resources in the SUS, and financial contribution impact analysis of incorporation of a new technology. Thirty-one (31) 12 years-old volunteers were evaluated.ResultsThe incremental cost-effectiveness ratio (ICER) was calculated at R$1.34/min, − R$0.60/min and BRL 0.10/min for the single-rooted, bi-rooted and tri-rooted teeth, respectively, when the rotary technique was compared with the manual type. In turn, the ICER was R$ 21.04/min, − R$ 0.73/min and − R$ 2.81/min for the 3 types of teeth, respectively, when the reciprocating technique was compared with the manual type. The incremental financial impact of replacing manual endodontic with rotary endodontic treatments would be − R$ 2060963.66 in the case of single-rooted teeth, but the number of treatments would also be reduced (− 19,379). In the case of two-rooted teeth, the incremental financial impact would be BRL 34921540.62 with the possibility of performing an additional 204,110 treatments. In turn, BRL 11523561.50 represented the incremental financial impact for teeth with 3 or more roots and with an increase of 72,545 procedures. When we analyzed the incremental financial impact of replacing manual endodontic with reciprocating endodontic treatments, it would be − R$ 730227.80 in the case of single-rooted teeth, allowing for an additional 2538 treatments. In turn, R$ 21674853.00 represented the incremental financial impact for bi-radicular teeth, with an increase of 121,700 procedures. In the case of two-rooted teeth, the incremental financial impact would be BRL 13591742.90 with the possibility of performing an additional 40,670 treatments.ConclusionsThe reciprocating technique could improve access to endodontic treatment in the SUS as it allowed a simultaneous reduction in clinical time and associated costs. However, the higher number of endodontic treatments performed would have a financial impact.

Interpretation of Root Canal Anatomy of Maxillary and Mandibular Permanent Canines in Saudi Subpopulation: A Cone-Beam Computed Tomography (CBCT) Study.

The objective of this investigation was to evaluate the root canal anatomy of permanent canines in a Saudi subpopulation utilizing CBCT. A total of 1328 CBCT images of maxillary (634) and mandibular (694) permanent canines were collected from Saudi patients who visited the College of Dentistry at King Saud University in Riyadh. The images were analyzed for root and canal numbers, canal configuration types, and symmetry between the bilateral canine teeth in each arch. Gender, age, and tooth position were recorded. The Kappa test was used for both inter- and intraexaminer reliabilities. Data were analyzed with the chi-square test at a P value ≤ 0.05. There were no two-rooted teeth in maxillary canines, and 1.89% had two canals. Double roots and double canals in mandibular canines were found in 2.88% and 9.94% of the teeth, respectively. Type I canal configuration was more common in maxillary canines (97.94%) compared to mandibular canines (92.07%). Maxillary canines showed higher bilateral symmetries of root and canal numbers and canal configuration types (100%, 98.1%, and 97.9%, resp.) compared to mandibular canines (97.1%, 90.1%, and 92.1%, respectively). The majority of maxillary and mandibular canines had a single root with a single canal and type I canal configuration. Mandibular canines are characterized by having more than one root and canal and alterations in root canal configurations compared to maxillary canines.

Cone-beam computed tomography evaluation of the root morphology of the maxillary and mandibular premolars in a Moroccan subpopulation: Number of roots and tooth length (part 1)

Introduction: The aim of the study was to evaluate the number of roots and tooth length of the maxillary and mandibular premolars of a Moroccan subpopulation using cone-beam computed tomography (CBCT). Materials and Methods: The number of roots and tooth length of 919 maxillary and mandibular premolars (358 maxillary and 561 mandibular) examined by CBCT was evaluated using “Planmeca viewer” software. Statistical analysis was carried out using the Epi info software. Results: The study showed a high prevalence of two roots for maxillary first premolars, and single root for maxillary second premolars and mandibular first and second premolars. The mean length of the maxillary first premolars (single rooted) was 21.74 mm, that of the buccal roots was 21.92 mm, and that of the lingual roots of the two-rooted teeth was 20.67 mm. The maxillary second premolars (21.4 mm) and the mandibular premolars (21.5 mm) exhibited the same mean length. Conclusion: All premolars had a single root in most cases, except for the maxillary first premolars where two-rooted teeth were more frequent with an average length of 21.4 mm. CBCT is an exciting tool for endodontic diagnosis and treatment planning.

Anatomic comparison and prevalence of additional canals in contralateral maxillary first and second molars using cone beam computed tomography - An ex vivo study.

Background:Numerous cone beam computed tomography (CBCT) studies have been done to analyze the canal anatomy of maxillary molars. However, research on comparison of symmetry in contralateral molars in the Indian population is limited.Aim:The aim of this study is to identify and assess the variations in the internal anatomy based on Vertucci's classification and to compare the prevalence of additional canals in contralateral maxillary first molar (Mx 1 M) and maxillary second molar (Mx 2 M) using CBCT.Settings and Design:A total of 120 small and medium field of view CBCT images with Mx1M and Mx2M were collected and retrospectively evaluated.Materials and Methods:Coronal, sagittal, and axial views of CBCT scans were analyzed by scrolling the scans, adjusting the contrast and brightness, and magnifying the canal configuration, along with additional canals and symmetry were identified and recorded.Statistical Analysis:Data were analyzed using McNemar's test and Chi-square test.Results:Both Mx1M and Mx2M showed bilateral symmetry in the mesiobuccal root with Type I canal anatomy in 86.1% and 97.8%, respectively. The MB2 canal was evident in 34.1% of Mx1M and 8.4% of Mx2M.Conclusion:Variations such a single-rooted and two-rooted teeth in Mx2M with Type I Vertucci's canal anatomy were seen. The MB2 canal was the only additional canal found.

Dental morphology of Adalatherium hui (Mammalia, Gondwanatheria) from the LATE Cretaceous of Madagascar

ABSTRACT The dentition in the only known specimen of Adalatherium hui, a gondwanatherian mammal from the Late Cretaceous of Madagascar, is markedly different from that of any previously known mammaliaform, extinct or extant. The two preserved upper incisors and single lower incisor of Adalatherium are each very large, open-rooted, and bear a restricted band of enamel. A shallow-rooted, rudimentary upper canine is present. The upper postcanine dentition is composed of a small, simple, two-rooted tooth mesially and four large, multiple-rooted (five roots or more) teeth distally. The latter are quadrangular in outline, each with four major cusps and three perimetric ridges bordering a central valley that opens buccally. There are four lower postcanines, also with four major cusps each. The first postcanine has two roots, but the following ones each have (or likely had) at least four. The two distal lower postcanines bear a prominent mesiobuccal basin. The cusps and other topographic features of the postcanines cannot be unambiguously homologized with those of other known mammaliaforms. Diastemata are present in the upper dentition between the incisors and canines and between the canines and postcanines, and in the lower dentition between the incisors and postcanines. Adalatherium, like several gondwanatherians from the Late Cretaceous and Paleogene of Argentina, retains relatively plesiomorphic, ‘normal’ radial enamel (i.e., single-layered schmelzmuster, non-decussating small prisms, interprismatic matrix anastomosing around prisms). This stands in contrast to the modified radial enamel found in other gondwanatherians from the Late Cretaceous of India and Madagascar, which exhibit prominent interrow sheets of interprismatic matrix.

Root and canal anatomy of mandibular first molar teeth of an Indian population

Aim: The current study evaluated the root and root canal anatomy of permanent mandibular first molar teeth of an Indian population. Materials and Methods: A total of 486 freshly extracted human permanent noncarious mandibular first molar teeth were acquired from a pool of extracted teeth of patients of indigenous Indian population. The root canal morphology (including the root numbers) and the anatomy of the root canal system (including the number and type of canals based on Vertucci's classification) were evaluated using cone-beam computed tomography. Results: Predominantly, the studied specimens exhibited two roots with a prevalence of 86.84%, followed by three roots with a prevalence of 13.16%. The third root was exclusively found on the lingual aspect of distal roots. The two- and three-rooted permanent mandibular first molars exhibited two, three, and four in 1.64%, 55.34%, and 43.02% of teeth, respectively. In the mesial roots, the most common pattern was Type IV (54.94%), followed by Type II (42.38%) and Type I (2.68%). In the distal roots, the most common pattern was Type I (53.29%), followed by Type II (31.06%), Type IV (9.47%), Type III (4.74%), and Type V (1.44%). The three-rooted permanent mandibular first molars exhibited Type I canal configuration in 100% of the specimens in the extra root. Conclusion: The most common morphology of permanent mandibular first molars of an Indian population was the two-rooted teeth with three canals (two mesial and one distal). The root canal configurations most commonly seen were Type IV in mesial roots and Type I in the distal roots. In teeth with three roots, the extra root it was located lingually and exhibited Type I root canal configuration.

Decision of Surgery According to Relation of Roots of Lower Third Molar to Inferior Alveolar Canal in Different Winter Classes of Impaction Depending Only on Orthopan-tomogram. Surgical prospective from a Retrospective Radiographic Study

Background and objectives: The proximity of inferior alveolar canal to roots of lower third molar is one of the serious challenges facing surgeons during extraction of that tooth. There are different types of this relation, mainly: away, in direct contact and crossing the canal. The aim is to evaluate the relation between roots of lower third molar and inferior alveolar canal, in Winter classification of impaction of impaction to decide whether to do surgery or to ask for Cone Beam Computed Tomography first. Methods:Orthopantomographs f 206 cases were retrospectively evaluated: the presence of impaction; applying Winter classification; studying roots, numbers; and their relation to the canal (away from, in direct contact and crossing). Results: One hundred and twenty-four cases were with lower third molar impaction; mean age (29.5 ± 6.2); mesioangular was the most common type of impaction. In general, 24 (19.5%) cases were away; 51 (40.5%) cases were with a direct contact; 49 (39.5%) cases were crossing the canal. In mesioangular im- paction the common relations were in direct contact and crossing the canal. There was large difference in prevalence of single-rooted and two-rooted teeth, with being two-rooted the common one, there were no significant differences in their relation to the canal. Two divergent rooted teeth majority were in direct contact with the canal. Conclusions: Our results showed that just 19.7%, regarding the relation to inferior alveolar canal are safe to do surgery without radio- graph, the rest has the risk of endangering the nerve and 40% needs computed tomography.

An innovative approach to salvage a fractured endodontically treated tooth – A case report of resection, regeneration and restoration

Introduction: The progressing inflammatory periodontal disease, if untreated, results in attachment loss. This can affect the furcation region of multirooted teeth. Hemisection is the splitting of two rooted tooth into two separate portions accompanying crown portion of two-rooted teeth most likely mandibular molars. In the healing phase after hemisection, alveolar bone undergoes additional atrophy as a result of the natural remodelling process. Post-extraction Alveolar Ridge resorption may have an impact on dental implant placement, since sufficient vertical and horizontal volume of alveolar bone should ideally be present at the site of insertion. Alveolar ridge preservation (ARP) procedures have been introduced for aesthetic concern, as well as to prevent alveolar ridge atrophy and maintain adequate dimensions of bone in order to facilitate implant placement in prosthetically driven positions. Case Description: A 51 years old systemically healthy male patient came with a chief complaint of pain and swelling in his lower left back tooth region. On clinical examination, Endodontically treated mandibular first molar manifested bucco-lingual fracture, grade 2 mobility of mesial component, 10 mm probing depth in mesial region and grade 3 furcation involvement. The treatment of the tooth included proposed hemisection of the mesial component followed by socket augumentation and delayed implant placement. After phase 1 therapy, hemisection was performed and mesial root socket was augumented with zenograft and PRF membrane. After 8 months, Osteotomy site was prepared with flapless procedure then narrow, two piece implant of size 3.3 × 11.5 mm was placed in hemisected region of mandibular molar which was followed by provisional restoration at 3 weeks. Conclusion: An innovative approach for a periodontally compromised fractured endodontically treated tooth which was undertaken with a definitive treatment. Keywords: Early loading, Furcation, Hemisection, Mandibular fir

Prevalence of a Second Root and Canal in Mandibular and Maxillary Canines in a Saudi Arabian Population: A Cone-beam Computed Tomography Study

This study evaluated the prevalence of a second root and canal, gender differences, and bilateral symmetry of mandibular and maxillary permanent canines in a Saudi Arabian population using a cone-beam computed tomography (CBCT). The first step was to evaluate CBCT images of 208 patients with 794 canines (410 mandibular and 384 maxillary canines). The second step was to identify the number of roots, number of canals, and canal configurations based on Vertucci's classification to investigate the prevalence of a second root and a second canal, gender differences, and bilateral symmetry. A Z test evaluated differences in the independent proportions; a Chi-square test determined differences between genders and Cohen's Kappa test assessed bilateral symmetry. The prevalence of two roots and two canals in mandibular canines was 2.7% and 9.3%, respectively, and Vertucci's type III appeared in 6.1%, and Vertucci's type V appeared in 3.2%. In maxillary canines, there were no two-rooted teeth, and only 1% of two canals were present with Vertucci's type III. There were no statistically significant differences between genders in both mandibular and maxillary canines. High bilateral symmetries of roots and canals appeared in mandibular canines (95.5% and 91.1%, respectively) and maxillary canines (100% and 98.9%, respectively). One root, one canal, and Vertucci's type I are the primary and typical characteristics of mandibular and maxillary canines. The presence of a second root in mandibular canines is small, although the presence of two canals is not unusual. Conversely, it is rare to find a second root and canal in maxillary canines. Mandibular canines showed bilateral asymmetry (8.9%) in the number of canals between the right and left sides, which could be of clinical importance when planning root canal treatment (RCT) on contralateral canines.

Root Canal Morphology of Maxillary Premolars among the Elderly.

Root Canal Morphology of Maxillary Premolars among the Elderly.

Retrograde root canal treatment: a prospective case series.

Root canal treatment of teeth with necrotic pulps and apical periodontitis may be complicated by limited access to the root canals due to restorations and dystrophic calcifications. The objective of this study was to evaluate retrograde root canal as a primary treatment using a surgical approach as an alternative to conventional orthograde treatment. Patients with apical periodontitis in the anterior region of the maxilla were consecutively recruited to the study over a period of 4years. Fifty-seven patients met the inclusion criteria and received retrograde root canal treatment. A clinical and radiographic evaluation was made after 1 and 2years postoperatively. Clinical and radiographically evaluation after 2years revealed a successful outcome (as defined in this study) in 90% of the cases. Retrograde root canal as a primary treatment was a reliable alternative to treat apical periodontitis on single- and two-rooted teeth with limited orthograde access to the root canals in the maxilla.

Hemisection-saving by Slicing

The progressing inflammatory periodontal disease, if untreated, ultimately results in tooth loss. This inflammatory process can also affect the bifurcation or trifurcation of multi-rooted teeth. A mandibular molar with Grade III furcation and an endodontic involvement has always been a challenge for treatment, management and long-term prognosis. Hemisection refers to the removal or separation of root with its accompanying crown portion of two-rooted teeth, most likely mandibular molars. It is one of the treatment options for preserving the remaining part of the molar having sound periodontium. The present case report demonstrates the successful management of Grade III furcation involvement by hemisection procedure in mandibular molar using a vertical cut method and rehabilitation with fixed prosthesis.

Management of periodontally compromised mandibular molar with Hemisectioning: A case report

Introduction: Hemisection involves sectioning of a periodontally involved mandibular molar so as to remove the involved root and save the remaining tooth. This procedure helps in saving a tooth which otherwise would have been deemed for extraction. Hemisection refers to removal or separation of root with its accompanying crown portion of two-rooted teeth, most commonly mandibular molars. Method: In this case report, an advanced Endo-Perio lesion on a left mandibular first molar was successfully treated by root-canal treatment and hemisection. This procedure helps preserve the tooth structure, alveolar bone and promote cost savings over other treatment options. Conclusion: Hemisection is a treatment option for saving a mandibular molar which is in advanced stage of periodontal disease of one root. Removal of the affected root will help in retaining the remaining tooth structure.

Hemisection — A Conservative Approach for a Periodontally Compromised Tooth: A Case Report

The progressing infl ammatory periodontal disease, if untreated, ultimately results in attachment loss. This can affect the bifurcation or trifuracation of multirooted teeth. Hemisection is the splitting of a two-rooted tooth into two separate portions. The treatment, management and long-term retention of mandibular molar teeth exhibiting furcation involvement always have been a challenge, especially when the furcation involvement has progressed to a class III furcation. Hemisection refers to removal or separation of root with its accompanying crown portion of two-rooted teeth most likely mandibular molars. Hemi-section of the affected tooth helps preserve the tooth structure, alveolar bone and promote cost savings over other treatment options. This article describes a simple procedure for hemisection in mandibular molar by vertical cut method and its subsequent restoration.