Healing and long-term prognosis of root-fractured permanent teeth: a retrospective longitudinal study.

AIM: The purpose of the present study was to evaluate permanent teeth with post-traumatic transversal root fractures, for their initial healing modality, the effect of candidate predictors and their long-term prognosis. METHODOLOGY: A retrospective longitudinal clinical study was conducted to evaluate records from patients bearing transversal root fractures in permanent teeth in order to radiographically assess short-term healing and non-healing events in the fracture line, their prognostic factors and their relationship with long term outcomes. The inter-fragmentary tissues were classified as healing: hard tissue (HT), connective tissue (CT) or connective tissue and bone (CT + B) and non-healing: interposition of granulation tissue (GT). A competing risk survival analysis was conducted to estimate the hazards of healing and non-healing events in the short-term and the effect of demographic, clinical, and treatment variables was assessed using the subdistribution regression model (Fine & Gray). RESULTS: Radiographic findings showed 61.4% of healing in the short-term being strongly influenced by the presence and type of concomitant injuries to the coronal fragment. Teeth with concomitant crown fractures (sHR 24.38, 95% CI [3.16-188.3], p = 0.0022), luxations with dislocations (sHR 10.58, 95% CI [1.37-81.9], p = 0.0240) and subluxations (HR 9.66, 95% CI [1.14-81.7], p = 0.0370) were more likely to present non-healing of root fractures in the short-term. The healing rate in the long-term was of 75.9%, most of them with interposition of bone and connective tissue. Kappa statistics demonstrated an overall agreement of 67.1% between short and long-term healing patterns, in special HT and CT + Bone modalities. CONCLUSION: Healing at the fracture site was the most frequent outcome, both in the short-term and in the long-term. Short-term healing modality was strongly influenced by the presence and type of concomitant injuries to the crown fragment, being the worst prognosis observed in root-fractured teeth with concomitant crown fractures, followed by concomitant luxations with dislocation. CLINICAL RELEVANCE: Post-traumatic transversal root fractures have a positive prognosis supporting therefore, a more conservative approach for these teeth before considering more radical treatments.

Assessment of the root and canal morphology in the permanent dentition of Saudi Arabian population using cone beam computed and micro-computed tomography - a systematic review.

INTRODUCTION: Root canal treatment procedures require a thorough understanding of root and canal anatomy. The purpose of this systematic review was to examine the morphological differences of teeth root and their canals assessed using cone-beam computed and micro-computed tomography in Saudi Arabian population. METHODOLOGY: An electronic search was conducted in PubMed / Medline, Scopus, Google Scholar, and Web of Science databases until January 2023 to retrieve related studies. "Root canal morphology," "Saudi Arabia," "Micro-CT," and "cone-beam computed tomography" were used as keywords. A modified version of previously published risk of bias assessment tool was used to determine the quality assessment of included studies. RESULTS: The literature search revealed 47 studies that matched the criteria for inclusion, out of which 44 studies used cone beam computed tomography (CBCT) and three were micro-computed tomography (micro-CT) studies. According to the modified version of risk of bias assessment tool, the studies were categorized as low, moderate, and high risk of bias. A total of 47,612 samples were included which comprised of either maxillary teeth (5,412), or mandibular teeth (20,572), and mixed teeth (21,327). 265 samples were used in micro-CT studies while 47,347 teeth samples were used in CBCT studies. Among the CBCT studies, except for three, all the studies were retrospective studies. Frequently used imaging machine and software were 3D Accuitomo 170 and Morita's i-Dixel 3D imaging software respectively. Minimum and maximum voxel sizes were 75 and 300 µm, Vertucci's classification was mostly used to classify the root canal morphology of the teeth. The included micro-CT studies were in-vitro studies where SkyScan 1172 X-ray scanner was the imaging machine with pixel size ranging between 13.4 and 27.4 µm. Vertucci, Ahmed et al. and Pomeranz et al. classifications were applied to classify the root canal morphology. CONCLUSION: This systematic review revealed wide variations in root and canal morphology of Saudi population using high resolution imaging techniques. Clinicians should be aware of the common and unusual root and canal anatomy before commencing root canal treatment. Future micro-CT studies are needed to provide additional qualitative and quantitative data presentations.

Diagnostic value of cone beam computed tomography for root canal morphology assessment - a micro-CT based comparison.

OBJECTIVES: The aim of this study was to assess cone beam computed tomography (CBCT) as a root canal anatomy diagnostic tool by comparison with micro-CT gold-standard. MATERIALS AND METHODS: 216 two-rooted mandibular molars were first scanned in a CBCT device (200 µm voxel size) and posteriorly in a micro-CT scanner (19.61 µm). The volumes were sequentially screened to classify main root canal anatomy according to Vertucci classification, and for the presence of lateral canals and apical deltas, in both mesial and distal roots. RESULTS: Both methods revealed a higher prevalence of Vertucci Type II and IV in the mesial root, and Vertucci Type I in the distal root. The percentage of agreement for main root canal anatomy classification between CBCT and micro-CT scores was high (85.2%). CONCLUSION: Sensibility to detect both lateral canals and apical deltas with CBCT was low. These results attest to the fact that minor anatomical changes might be difficult to identify with CBCT imaging, hampering its diagnostic value.

Evaluating the Internal Anatomy of Maxillary Premolars in an Adult Saudi Subpopulation Using 2 Classifications: A CBCT-Based Retrospective Study.

BACKGROUND Understanding the root canal morphology is important for successful endodontic treatment. This retrospective cone-beam computed tomography (CBCT) study aimed to compare the adult maxillary premolars (MP), root, and canal morphology among a Saudi Arabian subpopulation based on Vertucci and Ahmed classifications. MATERIAL AND METHODS Scans of 1336 MP - 656 first premolars (MFP) and 680 second premolars (MSP) - were analyzed for the number of roots, morphology of the canals, and symmetry among them. The data were grouped based on the traditional preestablished Vertucci system and newer instantaneous code-based Ahmed classification. Comparative analysis was done using the chi-square test. RESULTS Two roots were common in MFP with 84.4% of the population, followed by those with 1 root and those with 3 roots. In MSP, single roots were more common. The results were non-significant with P values of 0.859 and 0.471, respectively. Most of these MFP had Type IV Vertucci configuration/²TNB¹P¹ Ahmed et al code (TN-tooth number, B-buccal canal, P-palatal canal). In MSP, Type I Vertucci/¹TN¹ Ahmed et al code was most common. However, the results were not statistically significant for the PM with P values of 0.997 and 0.732, respectively. Sex-based difference among them for the roots and root canals was also non-significant. Symmetry among PM in opposite quadrants was 87.1% in MFP and 90% in MSP. CONCLUSIONS Two roots with Type IV (²TNB¹P¹) and 1 root with Type I (¹TN¹) were most common in MFP and MSP, respectively. Symmetry among opposing PM was high.

Clinical relevance of distolingual roots and periodontal status in mandibular first molars: a cross-sectional study employing CBCT analysis. / ä¸‹é¢Œç¬¬ä¸€ç£¨ç‰™è¿œèˆŒæ ¹çš„å­˜åœ¨ä¸Žç‰™å‘¨çŠ¶æ€çš„ä¸´åºŠç›¸å ³æ€§åˆ†æžï¼šä¸€é¡¹é‡‡ç”¨é”¥å½¢å°„æŸç”µè„‘æ–­å±‚æ‰«æåˆ†æžçš„æ¨ªæ–­é¢ç ”ç©¶.

OBJECTIVES: Distolingual root of the permanent mandibular first molar (PMFM-DLR) has been frequently reported, which may complicate the treatment of periodontitis. This study aimed to assess the morphological features of PMFM-DLR and investigate the correlation between the morphological features of PMFM-DLR and periodontal status in patients with Eastern Chinese ethnic background. MATERIALS AND METHODS: A total of 836 cone beam computed tomography (CBCT) images with 1497 mandibular first molars were analyzed to observe the prevalence of PMFM-DLR at the patients and tooth levels in Eastern China. Among them, complete periodontal charts were available for 69 Chinese patients with 103 teeth. Correlation and regression analyses were used to evaluate the correlation between the morphological features of DLR, bone loss, and periodontal clinical parameters, including clinical attachment loss (CAL), probing pocket depth (PPD), gingival recession (GR), and furcation involvement (FI). RESULTS: The patient-level prevalence and tooth-level prevalence of DLR in mandibular first molars were 29.4% and 26.3%, respectively. Multiple linear regression analysis suggested that bone loss at the lingual site and CAL were negatively affected by the angle of separation between distolingual and mesial roots in the transverse section, while they were significantly influenced by age and the angle of separation between distobuccal and mesial roots in the coronal section. CONCLUSIONS: The prevalence of PMFM-DLR in Eastern China was relatively high in our cohort. The morphological features of DLR were correlated with the periodontal status of mandibular first molars. This study provides critical information on the morphological features of DLR for improved diagnosis and treatment options of mandibular molars with DLR.

Natural canal deviation and dentin thickness of mesial root canals of mandibular first molars assessed by microcomputed tomography.

The aim of this study was to assess the centralization and dentin thickness of mesial root canals of the first mandibular molars by microcomputed tomography (micro-CT). Material and methods: Ninety-nine mandibular molars of Vertucci's type IV canals were scanned by micro-CT. The mesiodistal deviation and centroid were assessed, in both mesiobuccal (MB) and mesiolingual (ML) canals, for the apical 4mm and the full canal length. Results: The dentin thickness was similar for both MB and ML canals. The narrowest thickness was in the distal wall of an MB canal (0.07mm), while the widest was found in the mesial wall of an MB canal (2.46mm). In centroid analysis, both the MB and ML canals exhibited deviations when compared to the root centroid, along the full canal length and the apical 4mm. For the MB canal, the mean deviation was 0.83mm (0.02 mm-2.30 mm) for the full canal and 0.18mm (0.01 mm-1.01 mm) for apical 4mm. Similarly, for the ML canal, the mean deviation measured 0.83 mm (0.05mm-3.99mm) for the full canal and 0.21 mm (0.01mm-1.01mm) for the apical 4 mm. Overall, deviations were observed towards the mesial of the roots, with 69% for MB and 57% for ML canals for the full canal, and 51% for MB canals within the 4 mm. The exception was the ML canal, which exhibited a higher deviation towards distal in the apical 4mm, accounting for 52% of cases. The dentin thickness was consistent between the mesial canals of mandibular molars. However, there is no centrality of mesial canals in their roots, with frequent deviation to mesial.

Root canal morphology of anterior permanent teeth in Jordanian population using two classification systems: a cone-beam computed tomography study.

BACKGROUND: Adequate knowledge of root canal morphology and its variation is essential for success of root canal treatment and to overcome treatemnt failure. The aim of this study was to investigate the root and canal morphology of mandibular anterior teeth using 2 classification systems. METHODS: 3342 lower anteriors were evaluated from 557 CBCT scans. The images were examined in sagittal, axial and coronal views using a CS 3D imaging software (V3.10.4, Carestream Dental). Demographic data recorded, the number of roots and canal's morphology were described according to Vertucci and Ahmed classifications. RESULTS: Frequency of Type I configuration was significantly the highest in incisors and canines (76%, N = 2539), followed by Type III (20.6%, N = 687). Type II (1.1%, N = 37), IV (1.1%, N = 37), and V (0.3%, N = 11) were rarely encountered. 0.9% (N = 31) of the teeth could not be classified with the Vertucci System. The frequency of 2 roots (2MA in Ahmed classification) which has no correspondence in the Vertucci classification, was 1.1% (N = 38), it was significantly higher in canines and in females (35 canines and 3 laterals). A moderate correlation in root canal morpology was found between the left and right sides (V > 0.30). 80% (N = 2538) of the teeth did not exhibit any divergence/merging. The bifurcation level occurred mostly in the middle third of the root. CONCLUSIONS: One fourth of anterior teeth had variation from the simple type I canal configuration and therefore requires attention during treatment. The new classification system offers a more accurate and simplified presentation of canal morphology. CLINICAL RELEVANCE: The prevalence and mid root bifurcation of second canal in lower anteriors requires attention to ensure adequate quality root canal treatment without compromising the integrity of teeth.

Age estimation by pulp canal/root ratio in Yorkshire terrier dogs.

Background: The study of the morphological parameters of teeth on dental radiographic images, especially evaluation of the pulp canal/root ratio (PCRR), has been presented as a reliable method to estimate age both in humans and animals. Evaluating PCRR involves a simple, nondestructive procedure that can be used both in living individuals and in cadavers. There is a scarcity of studies assessing the relationship between PCRR and age in dogs (Canis lupus familiaris). Objective: The aim of this study was to evaluate the relationship between PCRR and age in Yorkshire terrier dogs. Animals and procedures: Dental radiographs of 53 Yorkshire terrier dogs from the database of the Odontovet Veterinary Dentistry Center (Brazil) were analyzed. Using ImageJ software, 3 consecutive measurements of the widths of 2 roots (mesial and distal) and their respective pulp canals were taken at both mandibular molar teeth (left, 309 and right, 409). The PCRR was then calculated using width means. Results: The PCRR decreased with increasing age in both mesial (0.21 ± 0.09 in animals aged < 24 mo, 0.12 ± 0.04 in animals aged between 25 and 96 mo, and 0.09 ± 0.03 in dogs aged > 96 mo) and distal (0.24 ± 0.11, 1.01 ± 0.03, and 0.09 ± 0.03, by the same order) roots. A statistically significant, moderate negative correlation was demonstrated between age and PCRR of the mesial [rs (97) = -0.545; P < 0.001] and distal [rs (98) = -0.578; P < 0.001] roots. Conclusion and clinical relevance: This work contributes to the knowledge of PCRR in dogs and its relationship with age, paving the way for further studies using larger samples in different canine breeds.

Estimation de l'âge par le rapport canal pulpaire/racine chez des chiens de race Yorkshire. Contexte: L'examen des paramètres morphologiques des dents sur des radiographies dentaires, particulièrement l'évaluation du rapport canal pulpaire/racine (PCRR), a été présenté comme une méthode fiable d'estimer l'âge chez les humains et les animaux. L'évaluation du PCRR est faite au moyen d'une procédure simple et non-destructive qui peut être utilisée autant chez les individus vivants que sur des cadavres. Il y a peu d'études évaluant la relation entre le PCRR et l'âge chez les chiens (Canis lupus familiaris). Objectif: L'objectif de la présente étude était d'évaluer la relation entre le PCRR et l'âge chez des chiens de race Yorkshire. Animaux et procédures: Les radiographies dentaires de 53 chiens de race Yorkshire provenant de la base de données du Centre de dentisterie vétérinaire Odontovet (Brésil) ont été analysées. À l'aide du logiciel ImageJ, 3 mesures consécutives de la largeur de 2 racines (mésiale et distale) et de leur canal pulpaire respectif ont été prises au niveau des dents molaires mandibulaires (gauche, 309 et droite, 409). Le PCRR a par la suite été calculé utilisant les moyennes des largeurs. Résultats: Le PCRR diminuait avec une augmentation de l'âge autant pour la racine mésiale (0,21 ± 0,09 chez les animaux âgés de < 24 mo, 0,12 ± 0,04 chez les animaux âgés entre 25 et 96 mo, et 0,09 ± 0,03 chez les chiens de > 96 mo) que pour la racine distale (0,24 ± 0,11, 1,01 ± 0,03, 0,09 ± 0,03, dans le même ordre d'âge). Une différence statistiquement significative, corrélation modérément négative a été mise en évidence entre l'âge et le PCRR pour la racine mésiale [rs (97) = −0,545; P < 0,001] et la racine distale [rs (98) = −0,578; P < 0,001]. Conclusion et pertinence clinique: Cette étude contribue à la connaissance du PCRR chez les chiens et sa relation avec l'âge, ouvrant la voie à des études ultérieures avec un échantillonnage plus grand et différentes races de chien.(Traduit par Dr Serge Messier).

The osteoclastic activity in apical distal region of molar mesial roots affects orthodontic tooth movement and root resorption in rats.

The utilization of optimal orthodontic force is crucial to prevent undesirable side effects and ensure efficient tooth movement during orthodontic treatment. However, the sensitivity of existing detection techniques is not sufficient, and the criteria for evaluating optimal force have not been yet established. Here, by employing 3D finite element analysis methodology, we found that the apical distal region (A-D region) of mesial roots is particularly sensitive to orthodontic force in rats. Tartrate-resistant acidic phosphatase (TRAP)-positive osteoclasts began accumulating in the A-D region under the force of 40 grams (g), leading to alveolar bone resorption and tooth movement. When the force reached 80 g, TRAP-positive osteoclasts started appearing on the root surface in the A-D region. Additionally, micro-computed tomography revealed a significant root resorption at 80 g. Notably, the A-D region was identified as a major contributor to whole root resorption. It was determined that 40 g is the minimum effective force for tooth movement with minimal side effects according to the analysis of tooth movement, inclination, and hyalinization. These findings suggest that the A-D region with its changes on the root surface is an important consideration and sensitive indicator when evaluating orthodontic forces for a rat model. Collectively, our investigations into this region would aid in offering valuable implications for preventing and minimizing root resorption during patients' orthodontic treatment.

[Root canal therapy of maxillary molars with atypical canals: A report of three cases].

Maxillary molar with three roots and 3 to 4 canals is a common occurrence. However, in addition to common root canal anatomy, there may be significant differences in the number, distribution, and morphological structure of root canals. The success of root canal treatment is dependent on ensuring that all the intricate details associated with it are meticulously followed. Failure to locate all canals could have a negative effect on the treatment as it may lead to initiation or continuation of periapical pathology. Missed canals were the main reason for patients reporting back for nonsurgical root canal retreatment. Moreover, the bacteria residing in such canals could also result in persistence of symptoms. Root canal anatomy is complex, and the recognition of anatomic variations could be a challenge for clinicians. This article presents three cases of endodontic management of maxillary molars with atypical canal morphology. In the three cases of this study, the patients underwent cone beam computed tomographic (CBCT) examination before root canal treatment. The CBCT images revealed that the maxillary molars in case 1 and case 2 had 5 canals. Case 1: 2 mesiobuccal (MB, MB2), two distobuccal (DB and DB2), and one palatal canal. Case 2: 2 mesiobuccal (MB, MB2), one distobuccal (DB), and two palatal canals (MP and DP). In case 3, CBCT scan slices showed that the maxillary first molar presented as a C-shaped root canal with a rare tooth anomaly of taurodontism. Although C-shaped root canals were most frequently seen in the mandibular second molar, they might also appear in maxillary molars. A literature search revealed only a few case reports of C-shaped root canal systems in maxillary molars. Case 3 described the fusion between mesiobuccal and palatal roots of the maxillary first molar, forming a C-shaped mesiopalatal root canal. The above cases suggest that endodontists should always be aware of aberrancies in root canal system apart from the knowledge of normal root canal anatomy. CBCT as a means of diagnosis can be helpful for identifying and managing these complex root canal systems. This case series also highlights the importance of magnification and illumination. Through using an endodontic microscope, clinicians can identify root canals that are difficult to locate or overlooked with normal vision. A correct access opening is a most important step to locate and negotiate the orifices of root canals. The use of ultrasonic tips can refine the access cavity and allow controlled and delicate removal of calcifications and other interferences to the canal orifices, thereby helping to locate the extra orifices.

Retrospective study of the morphology of third maxillary molars among the population of Lower Silesia based on analysis of cone beam computed tomography.

INTRODUCTION: Understanding the anatomy of root canal systems and being aware of their variations is crucial for successful endodontic treatment. Specifically, the intricate and diverse nature of the root anatomy in maxillary third molars poses a significant challenge for dental clinicians. The study analyzed the morphology of the root canal system in maxillary third molars among residents of the Lower Silesia region in Poland using cone beam computed tomography (CBCT). MATERIAL AND METHODS: This retrospective cross-sectional imaging study was conducted at the X-Ray Diagnostics Laboratory of the Academic Dental Polyclinic of Wroclaw Medical University, Poland. The study evaluated 316 CBCT scans and included 196 maxillary third molars. They were obtained from 118 females and 78 males over the age of 18, in the period from January to April 2022 (three consecutive months). The number of roots, root canals, and root canal configurations according to Vertucci's classification were analyzed. RESULTS: Three-rooted maxillary molars were found most often (64.29%), followed by single-rooted (24.49%), two-rooted (7.65%), and four-rooted (3.57%) teeth. Among all the roots examined, Vertucci Type I root canals were the most prevalent. Our research found that single-rooted forms (40 teeth, 33.89% vs. 8 teeth, 10.26%, p = 0.0013) of maxillary third molars were significantly more common in females than in males. However, three-rooted forms (62 teeth, 79.49% vs. 64 teeth, 54.24%, p = 0.0013) of maxillary third molars were significantly more common in males than in females. DISCUSSION: In the Lower Silesia region, the typical maxillary third molar in the Polish population has a three-rooted structure with Vertucci Type I root canal configuration. We noted a sex-dependent correlation in maxillary third molar morphology, with single-rooted forms more prevalent in women and three-rooted forms in men.

Radiographic Criteria for Differential Diagnosis Between Vertical Root Fracture and Apical Periodontitis in Single-Rooted Endodontically Treated Premolars Using Cone-Beam Computed Tomography.

INTRODUCTION: This study explores the differences between the patterns of bone defects associated with vertical root fracture (VRF) and apical periodontitis (AP) in single-rooted endodontically treated premolars (SRETPs) based on cone-beam computed tomography (CBCT) data. METHODS: Eighty-four SRETPs were extracted and categorized into the VRF and AP groups. On preoperative CBCT images, the location of bone defects according to the root thirds in buccolingual and mesiodistal directions across the study groups were compared. RESULTS: The majority of bone defects in the VRF group were longitudinal and combined, involving more than one root thirds in buccolingual and mesiodistal directions simultaneously. A uniform approach to comparing bone defects using the sites of periradicular area with bone loss as a comparison unit was developed. In the VRF group, bone loss sites in the middle and coronal thirds were detected more often and were located mainly buccolingually compared with the AP group (P < .001). CONCLUSION: Bone defects in the middle or middle and coronal root thirds in the buccolingual direction may be potential radiographic signs useful in differentiating between VRF and AP in SRETPs. The introduction of the uniform approach to assessment of bone loss patterns will give practitioners a single simple tool and improve the quality of endodontic treatment.

Micro computed tomography (Micro-CT) characterization of root and root canal morphology of mandibular first premolars: a systematic review and meta-analysis.

INTRODUCTION: Mandibular first premolars are familiar with their varied root canal morphology, causing difficulties and challenges for successful endodontic procedures. This systematic review and meta-analysis aim to study the characterization of root and canal morphology of the first mandibular premolar using micro-computed tomography. METHODOLOGY: The literature search was conducted using electronic web databases like PubMed, Scopus, ScienceDirect and Cochrane with the chosen MeSH key words and data was retrieved until May 2023. Further to perform the statistical analysis, R v 4.3.1 software with "meta", 'metafor" "metaviz" " ggplot2" package was used, and results were represented by odds ratios (OR) and the percentage of forest plots along a 95 per cent confidence interval (CI). RESULTS: The total number of studies meeting the inclusion criteria was 13; these studies were conducted on mandibular first premolar using Micro-CT; the total sample size was 1817. To scan the sample, an X-ray micro-focus CT system (Siemens Inveon CT, Erlangen, Germany) was used in four studies and seven different machines were used in the respective studies. Mimics 10.01 software (Materialize, Leuven, Belgium) and NRecon v.1.6.9 software (Bruker, Kontich, Belgium) were commonly operated. The minimum and maximum voxel size ranges between 11.94 and 50 µm. Vertucci's classification was frequently used (9), while one study applied Ahmed et al. and Vertucci's classification. CONCLUSION: This systematic review provides essential information about the root and canal configurations, radicular grooves, accessory canals, and apical foramina through Micro-CT, aiming to improve the accuracy of endodontic treatment and help practitioners.

Distolingual root prevalence in mandibular first molar and complex root canal morphology in incisors: a CBCT analysis in Indian population.

Cone-beam computed tomography was used to understand the possible correlation between the prevalence of distolingual root (DLR) in permanent mandibular first molars (MFMs) and the associated complicated mandibular incisor's root canal morphology (MIs) in an Indian population. A total of 400 scans were evaluated for MFMs and MIs. The prevalence of DLRs and root canal anatomy of MIs were assessed based on Vertucci's classification, and then the sample were grouped according to age, sex and side. Statistical analysis was used to evaluate the possible correlation between the presence of DLRs in the first molar and root canal morphology of incisors. Chi square test was used to evaluate the correlation between the root canal configurations of MIs with the existence of DLRs in MFMs. There was no statistically significant difference between sexes or ages for the prevalence of DLRs in the first molars (p > 0.05), which was 6.62%, with the right side having a greater frequency of DLRs (7.8%) than the left (5.5%). Vertucci Type I canal configuration was most common for the mandibular central (66.75%) and lateral incisors (58.62%). Vertucci Type III was the most common complicated canal morphology, followed by Types V, II, and IV for MIs, with no statistically significant difference in the studied sample's age and sex. (p < 0.05). No association was observed between the presence of DLRs in first molars and complicated root canal configurations in MIs. Taken together, the possibility of complicated root canal configuration in MIs was lesser in the presence of DLRs in MFMs among the Indian population.

Three-dimensional surface area analyses of developing maxillary second premolar root apices for age estimation using CBCT images.

Three-dimensional surface area analyses of developing root apices for age estimation in children and young adults have shown promising results. The current study aimed to apply this three-dimensional method to develop a regression model for estimating age in Malaysian children aged 7 to 14 using developing maxillary second premolars. A training sample of 155 cone-beam computed tomography scans (83 Malays and 72 Chinese) was analysed, and the formula was subsequently validated on an independent sample of 92 cone-beam computed tomography scans (45 Malays and 47 Chinese). The results showed a strong correlation (r = 94 %) between the chronological age as a dependent variable and the predictor variables, including root surface area of the apex, sex, ethnicity, and root development status (open/closed apices). For this model, the predictor variables accounted for 88.4 % of the variation in age except sex and ethnicity. A mean absolute error value of 0.42 indicated that this model can be reliably used for Malaysian children. In conclusion, this study recognises the method of three-dimensional surface area analyses as a valuable tool for age estimation in forensic and clinical practice. Further studies are highly recommended to assess its effectiveness across different demographic groups.

Influence of an adjacent zirconium implant, tube current, and metal artifact reduction algorithm on horizontal root fracture diagnosis in cone beam computed tomography.

OBJECTIVE: We evaluated the influence of an adjacent zirconium implant, tube current (mA), and a metal artifact reduction algorithm (MARA) on horizontal root fracture (HRF) diagnosis in cone beam computed tomography (CBCT). STUDY DESIGN: Nineteen teeth (9 with HRF, 10 without) were individually placed in a human maxilla. Scan volumes were acquired without and with a zirconium implant adjacent to the tooth at settings of 4, 8, and 10 mA, with MARA disabled and enabled, using a 5×5 cm field of view, 0.085-mm voxel size, and 90 kV. Four maxillofacial radiologists individually assessed the scans. Diagnostic metrics were compared by multiway analysis of variance (α=5%). Inter- and intraexaminer agreements for HRF diagnosis were evaluated with the weighted kappa test. RESULTS: Area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were significantly lower in the presence of the implant (P≤.005). AUC values were higher in scans obtained with 8 and 10 mA compared with 4 mA (P=0.010), but 10 mA without MARA was better with the implant present. MARA did not significantly influence outcomes (P≥0.240). Inter- and intraexaminer agreements ranged from moderate to almost perfect. CONCLUSIONS: The presence of the zirconium implant impairs HRF detection. Settings of 8 or 10 mA improve HRF detection regardless MARA condition without the implant. With an adjacent implant, 10 mA without MARA is recommended to improve diagnostic performance.

Dental age assessment in the living: a comparison of two common stage classifications for assessing radiographic visibility of the root canals in mandibular third molars.

After dentition is complete, degenerative tooth characteristics can be used for dental age assessment. Radiological assessment of the visibility of the root canals of the mandibular third molars in dental panoramic radiographs (DPRs) is known to be one such suitable feature. Essentially, two different stage classifications are available for evaluating the visibility of the root canals of mandibular third molars in the DPR. The aim of this study was to determine if one method outperforms the other. Therefore, the 2010 method of Olze et al. was directly compared to the 2017 method of Lucas et al. in the 2020 modification of Al Qattan et al. To this end, 233 DPRs from 116 females and 117 males aged 20.0 to 40.9 years were evaluated by three independent experienced examiners. In addition, one examiner ran two independent evaluations. Correlation between age and stage was investigated, and the inter- and intra-rater reliability was estimated for both methods. Correlation between age and stage was higher with the Olze method (Spearman rho 0.388 [95% CI 0.309, 0.462], males and 0.283 [95% CI 0.216, 0.357], females) than the Lucas method (0.212 [95% CI 0.141, 0.284], males and 0.265 [95% CI 0.193, 0.340], females). The intra-rater repeatability of the Olze method (Krippendorff's α = 0.576 [95% CI 0.508, 0.644], males and α = 0.592 [95% CI 0.523, 0.661], females) was greater than that for the Lucas method (intra-rater α = 0.422 [95% CI 0.382, 0.502], males and α = 0.516 [95% CI 0.523, 0.661], females). Inter-rater reproducibility was also greater for the Olze method (α = 0.542 [95% CI 0.463, 0.620], males and α = 0.533 [95% CI 0.451, 0.615], females) compared to the Lucas method (α = 0.374 [95% CI 0.304, 0.443], males and α = 0.432 [95% CI 0.359, 0.505], females). The method of Olze et al. was found to present marginal advantages to the Lucas et al. method across all examinations and may be a more appropriate method for application in future studies.

Predictor Mandibular Dentoalveolar Features on the Occurrence of 1-Rooted/C-Shaped Mandibular Second Molar Teeth.

OBJECTIVE: This study aimed to examine the mandible form features of the mandible, such as inter-second molar width, anteroposterior length, arch perimeter length, arch breadth, corpus height/width in the mandibular second molars (MnSM) region, and arch form, and the relation for the occasion of the 1-rooted/C-shaped. METHODS: The study analyzed cone-beam computed tomography images of 215 male and 215 female Turkish patients to determine the prevalence of 1-rooted and C-shaped MnSM. Mandibular dentoalveolar characteristics of individuals with bilateral (1R-1R group) and unilateral (1R-2R group) 1-rooted MnSM were examined and compared with those with bilateral 2-roots (2R-2R group) MnSM. Statistical tests were performed using Chi-square, one-way ANOVA, Tukey, and binary logistic regression analysis at the 5% significance level. RESULTS: The prevalence of 1-rooted and 1-rooted/C-shaped MnSM was 12.79% and 9.65%, respectively. Root fusion was more commonly present in females (p<0.05). In the 1R-1R group, the anteroposterior length was shorter than in the 2R-2R group (p<0.05). There was no difference between the groups for other features (p>0.05). CONCLUSION: Although the study found a shorter anteroposterior length in the 1R-1R group, no feature was a predictive variable for 1-rooted/C-shaped MnSM.

Appropriate timing of treatment contributes to better root development of impacted anterior teeth in children.

INTRODUCTION: This study investigated the effects of different timings of orthodontic treatment on the root development of impacted anterior teeth in children. METHODS: The cone-beam computed tomography (CBCT) data of 45 children with impacted anterior teeth were divided into unformed root (UR) group or basically formed root (BFR) group to evaluate root length (RL) and root growth length (RGL) of impacted teeth and contralateral nonimpacted teeth pretreatment and posttreatment. In addition, 22 patients with impacted dilaceration were selected to assess the effects of the crown-root angle and root development stage on RL and RGL. The Student t test, Wilcoxon test, analysis of variance, and multiple linear regression analysis were used for statistical evaluations. RESULTS: The RL of treated impacted teeth pretreatment and posttreatment was significantly shorter than contralateral nonimpacted teeth values (P <0.05). Posttreatment, the RL and RGL of impacted teeth of the UR group were significantly greater than those of the BFR group (P <0.05). The RGL of the dilacerated root in the UR group was considerably higher than in the BFR group (P <0.05). The larger crown-root angle group had a longer posttreatment RL (P <0.05). Multiple linear regression analysis revealed that the Nolla stage of impacted teeth and RL of contralateral teeth pretreatment significantly influenced the RL of impacted teeth posttreatment. CONCLUSIONS: Prompt orthodontic treatment is necessary for children with impacted anterior teeth to release the impacted state and achieve better root development. The root length of a dilacerated tooth continued to develop under treatment, but the crown-root angle partly constrained it.

Characteristics of CBCT versus panoramic signs of the surrounding bone of molar root protrusions into the maxillary sinus.

The study aimed to (a) investigate the amount and characteristics of the surrounding bone of protruded molar roots into the maxillary sinus using cone-beam computed tomography (CBCT) and (b) assess the correlation between the amount of bone with panoramic high-risk signs. Radiographs of 408 roots protruding beyond the sinus floor were evaluated. Axial CBCT images were used to investigate then classify eight characteristics of surrounding bone: no bone; bone < half the root girth in the proximal or buccal-palatal aspect; bone covering half the root girth in the proximal or buccal-palatal aspect; bone > half the root girth in the proximal or buccal-palatal aspect; and, complete bone. These were then grouped into four degrees of bone support: no bone; bone ≤ half the root girth; bone > half the root girth; and, complete bone. Panoramic signs were subclassified as: projection of root; interruption of the sinus floor; darkening of the root; upward curving of the sinus floor; absence of periodontal ligament space; and, absence of the lamina dura. Correlation between the degree of bone and the panoramic signs was evaluated using the Chi-square or Fisher's exact tests. Positive and negative predictive values, sensitivity, specificity, accuracy, and receiver operating characteristic analysis were calculated. Complete bone support was the most common. 'Projection of root' had a high negative predictive value and sensitivity. 'Absence of the periodontal ligament space and lamina dura' had a high positive predictive value, specificity, accuracy, and area under the curve. These two signs were significantly correlated with the degree of bone support.