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Purpose: To compare the volumetric loss of clinical crown structure in commonly encountered clinical situations for monolithic ceramic crowns, occlusal overlays, and partial-coverage onlays. Materials and Methods: Typodont teeth made with preexisting mesio-occlusodistal (MOD) preparations for mandibular first molars and maxillary first premolars were prepared with three different preparations: a full-contour monolithic zirconia crown, a lithium disilicate occlusal overlay, and mesio-occlusodistobuccal/mesio-occlusodistolingual (MODB/MODL) lithium disilicate onlays for premolars and molars. 3D-metrologic software was used to evaluate the volumetric loss of clinical crown structure for each preparation type. Subsequently, the mesiolingual cusps of mandibular molars and buccal cusps of maxillary premolars were excluded for a separate analysis to simulate patient presentation with an existing restoration and sheared-off cusp. Results: Full-coverage monolithic zirconia crowns removed 45.37 to 219.53 mm³ of the remaining clinical tooth structure, depending on the clinical scenario and tooth position, while lithium disilicate overlays removed 27.48 to 105.13 mm³ and MODB/MODL lithium disilicate onlays removed 5.48 to 47.45 mm³. In each scenario tested, MODB/MODL onlays removed significantly less clinical crown structure than overlays (P < .001); both MODB/MODL onlays and overlays removed significantly less structure than full-coverage crowns (P < .001). Conclusions: Monolithic zirconia crown restorations require significantly more removal of remaining tooth structure than lithium disilicate occlusal overlays and partial-coverage onlays for commonly occurring clinical situations requiring indirect restorations. [ABSTRACT FROM AUTHOR]

Autotransplantation has been proven as a viable method of reconstructing missing teeth. While preparing the recipient site, the bone reduction location depends largely on the surgeon's experience. Inappropriate overpreparation can cause biologic and esthetic complications, such as buccal or lingual bone resorption. This paper provides an innovative method to aid clinicians in precisely preparing a recipient site with the assistance of medical image-processing software and a real-time navigation system. This case report presents the autotransplantation of a mandibular molar using this technique with good short-term (6 months) clinical outcomes, including radiographic bone fill, normal probing pocket depth, physiologic tooth mobility, acceptable gingival level, and satisfactory restoration. [ABSTRACT FROM AUTHOR]

Background: First permanent molars (FPM) are highly susceptible to decay before the age of 15. When they are severely affected, the decision between conservation and extraction arises, particularly considering the potential for the second permanent molar (SPM) to replace the FPM. This cohort study aimed to evaluate clinical practices regarding FPM pulp necrosis treatment in children aged eight to twelve in two hospital departments in the Paris region. A second objective was to evaluate the one-year outcomes of the two therapies. Methods: A retrospective analysis was conducted using computerized billing software to identify patients aged eight to twelve who underwent either extraction or root canal treatment (RCT). Data collected included sex, age, arch involved, number of decayed surfaces, presence of Molar Incisor Hypomineralization (MIH), presence of infection, and treatment type. Results: A total of 66 patients were included, representing 61 extracted teeth and 23 RCT. Three main decision criteria were identified: presence of MIH (p < 0.005), extent of decay (p < 0.05), and SPM Nolla's stage. A total of 48% of the patients were seen at one year. A total of 16 of the 32 extractions and five of the nine RCTs had favorable evolution (p = 1). Conclusions: The question of whether to perform RCT or extraction of necrotic FPM in children aged eight to twelve is difficult to assess. It appears that five criteria need to be considered before the decision: possibility of long-term sealed coronal reconstruction, SPM Nolla's stage, follow-up possibilities, arch concerned, and presence of third permanent molar. [ABSTRACT FROM AUTHOR]

(1) Background: This study aimed to compare the shaping abilities of modern minimally invasive endodontic systems using natural teeth and 3D-printed resin replicas. These replicas offer a standardized approach for studying root canal preparation while eliminating the variability and scarcity of natural teeth. (2) Methods: Eleven mandibular molars with Vertucci class IV anatomy and their 3D-printed replicas (n = 132 canals) were scanned using micro-CT before and after preparation with six rotary systems. Shaping abilities were assessed by comparing volume, surface area, and unprepared areas between natural teeth and their 3D replicas, focusing on the apical third. Statistical analysis included the Shapiro–Wilk test to assess data normality and ANOVA and t-tests to compare different endodontic systems. (3) Results: Both qualitative and quantitative analyses revealed high similarity between natural teeth and 3D replicas. No significant differences in volume or surface area were found except in the apical third, where 3D replicas showed slightly larger increases in volume. (4) Conclusions: 3D resin replicas closely mimic natural teeth and provide a practical tool for assessing the shaping abilities of endodontic systems. This study demonstrates that 3D-printed models are suitable for endodontic research, offering a standardized and accessible alternative to natural teeth. [ABSTRACT FROM AUTHOR]

Heleocola piceanus, a new, relatively large metatherian from Upper Cretaceous ('Edmontonian') strata of the Williams Fork Formation in northwestern Colorado is described, based on a recently discovered jaw fragment (MWC 9744), in addition to three isolated teeth initially referred by other studies to Aquiladelphis incus and Glasbius piceanus. Although sharing several morphologic characters with the Lancian genus Glasbius, H. piceanus lower molars are considerably larger than those of Glasbius and differ from the latter in lacking a buccal cingulid, possessing carnassiform notches on the cristid obliqua and entocristid, and bearing an entoconulid on m3. To examine the relationship of Heleocola piceanus to other metatherians, H. piceanus was scored into a previously existing taxon-character matrix. Our phylogenetic analysis recovers H. piceanus as the sister taxon to Glasbius, which is consistent with our morphologic comparisons. H. piceanus represents the oldest member of the Glasbiidae. A regression equation for predicting body mass of dentally conservative metatherians that utilizes the length of m1 estimates the mass of H. piceanus at 855–1170 g, which is comparable in mass to today's muskrat (Ondatra zibethicus) and large relative to other Late Cretaceous pediomyoids. Based upon its molar morphology, specifically the low inflated cusps, low height differential between the trigonid and talonid, and near-bunodont morphology, H. piceanus is interpreted as an omnivore with a plant-dominated diet. [ABSTRACT FROM AUTHOR]

This study investigates the feasibility of a dynamic navigation system (DNS) small field of view workflow (DNS-SFOVw) for fiber-post removal and compares its accuracy and efficiency to the conventional large field of view workflow (DNS-LFOVw). Fifty-six extracted human maxillary molars were divided into DNS-SFOVw (n = 28) and DNS-LFOVw (n = 28). The palatal canal was restored with an intraradicular RelyX fiber post and luted with RelyX Unicem; a core buildup was used. Teeth were mounted in a 3D-printed surgical jaw. A preoperative cone-beam computed tomography (CBCT) scan was taken with a 40 × 40 mm FOV for the DNS-SFOVw and a single arch CBCT scan for the DNS-LFOVw. The drilling entry point, trajectory, angle, and depth were planned in the X-guide software. The DNS registration method for the DNS-SFOVw was virtual-based registration on teeth, and the marker point-based method was used for the DNS-LFOVw. The fiber posts were drilled out under DNS guidance. A postoperative CBCT scan was taken. Three-dimensional deviations, angular deflection, number of mishaps, registration, and total operation time were calculated. The DNS-SFOVw was as accurate as DNS-LFOVw (P >.05). The DNS-LFOVw registration time was less than DNS-SFOVw (P <.05). There was no difference in the number of mishaps (P >.05). Both DNS-SFOVw and DNS-LFOVw were time-efficient, with DNS-LFOVw taking less total operational time (P <.05). Within the limitations of this in-vitro study, the DNS-SFOVw was as accurate as the DNS-LFOVw for fiberpost removal. Both DNS-LFOVw and DNS-SFOVw were time-efficient in removing fiber-posts. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to compare the efficiency of temporary anchorage devices (TADs) and fixed functional appliances (FFAs) for mandibular molar protraction. Methods: Orthodontic records of 1050 consecutively treated patients with molar protraction were screened. Thirty‐six records (22 females and 14 males; mean age, 17.4 years) were divided into two groups: TAD (21 subjects with 25 edentulous spaces) and FFA (15 subjects with 24 edentulous spaces). The primary outcome measure was the efficiency of protraction [magnitude and time required for protraction (rate) and anchor loss (AL)]. The secondary outcomes involved measuring the type of tooth movement (TOTM), external apical root resorption (EARR), alveolar bone height change (ABHC), alveolar bone width change (ABWC) and appliance failure. Results: The rate of tooth movement was significantly higher for FFAs (0.83 ± 0.35 mm/month) versus TADs (0.49 ± 0.2 mm/month) (P =.005). Total treatment duration was less for FFAs (34.78 ± 8.1 months) versus TADs (47.72 ± 13.94 months) (P =.002). TOTM was similar for both (P =.909). EARR was 1.42 ± 1.38 mm for TAD and 1.25 ± 0.88 mm for FFA (P =.81). ABHC increased in the FFA group (1.01 ± 3.62 mm) and decreased for the TAD group (0.68 ± 1.66 mm). ABWC increased for both TAD (1.81 ± 1.73 mm) and FFA (1.75 ± 1.35 mm). The failure rate was 50% for FFAs and 33% for TADs. Conclusions: Both systems provided translation of lower molars with comparable anchorage control. However, FFAs were more efficient than TADs for lower molar protraction. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the accuracy of tooth positions in printed complete dentures with different designs and teeth positioning techniques. Materials and Methods: Five different designs of complete dentures and teeth positioning techniques were evaluated in this in vitro study. In Group I, the denture bases and teeth were designed as a single piece. In groups II and III, the denture bases were designed separately, and the denture teeth were designed as separate teeth. In groups IV and V, the denture bases were designed separately, and the denture teeth were designed as a single piece. Teeth positioning keys were designed for groups III and V. The dentures of all groups were scanned, and the data were imported to the surface matching software to evaluate the accuracy of the teeth positions. Statistical analysis was done using One ‐way ANOVA of Variance. The significance level was set at p ≤ 0.05. Results: The results showed that the highest deviations of the positions of the canines (0.0781 ± 0.0154 mm) and the first molars (0.0611 ± 0.0055 mm) were found in Group II. On the other hand, Group I showed the least deviations of the positions of the canines (0.0287 ± 0.0054 mm) and molars (0.0354 ± 0.005 mm). Conclusions: The most accurate tooth positions are obtained in monolithic printed complete dentures. Fewer deviations in tooth positions occur when denture teeth are designed as a single piece. [ABSTRACT FROM AUTHOR]

Background/Objectives: Many older adults living in long-term care (LTC) environments have varying numbers of retained natural teeth. The objective of this study was to assess the disease findings based on tooth type and estimate the role of tooth types in occlusion. Methods: We conducted clinical oral examinations of 276 LTC residents. The disease findings were analyzed for each tooth type and to determine their associations with dementia. Results: In total, 67.8% of the participants had molar teeth. Premolars/canines were often present as residual roots and had caries. Deepened periodontal pockets and higher plaque index (PI) values for molars had odds ratios of 2.5 (95% confidence interval [CI] of 1.59–3.91) and 1.61 (95% CI of 1.29–2.02), respectively. Participants with dementia were more likely to have incisors and premolars/canines in the form of root remnants and higher PI scores for all tooth types (p ≤ 0.01), as well as more deepened periodontal pockets in all teeth (p = 0.029), than those without dementia. The median number of remaining molars per participant was 3 out of a maximum of 12 (95% CI 3.4–4.0); thus, they often lacked occlusal contact. Conclusions: The LTC residents' molars were more prone to periodontal problems, whereas their premolars/canines often had caries or were present in the form of root remnants, especially in the participants with dementia. People's teeth should be treated in an easy-to-maintain way before they move into LTC to enable daily oral hygiene measures and maintain oral health. [ABSTRACT FROM AUTHOR]

Aim: To describe the management of the palato‐mesiobuccal (PMB) canal in maxillary second molars with fused roots using conventional techniques. Summary: Root canal treatment success hinges upon effectively addressing the intricate and variable anatomy of molar teeth. Failure to do so can lead to persistent infections and treatment failure. Recent advancements in imaging technologies have provided unparalleled insights into dental anatomy, especially in molars. Among these discoveries is the PMB canal, a unique anatomical variant recently reported for the first time in Endodontic literature. This canal, found in maxillary second molars with fused roots and originating from the coronal third of the palatal canal while traversing towards the mesiobuccal root presents challenges in clinical management due to its location. This article is the first to showcase the management of the PMB canal using conventional techniques. In the first case, a 38‐year‐old male patient presented with asymptomatic irreversible pulpitis in the maxillary second right molar. Following thorough instrumentation and irrigation, the presence of the PMB canal was discovered during root canal preparation. The canal was managed using rotary instruments and obturated successfully, resulting in a symptom‐free tooth at an 8‐year follow‐up. The second case illustrates a similar scenario in a 23‐year‐old female patient presenting with symptomatic irreversible pulpitis in tooth 17. The PMB canal was identified during treatment and managed using rotary nickel‐titanium instruments, leading to a favourable outcome at a 9‐year follow‐up. Key learning points: In fused roots of maxillary second molars, a PMB canal might be expected.Exploration of the buccal wall of the palatal canal under magnification after shaping procedures can reveal the PMB canal orifice in fused roots.Small tapers are suggested for the enlargement of the PMB canal.Continuous bleeding spots in the palatal canal might indicate a possible PMB canal orifice in vital cases.The use of an apex locator is suggested for the differential diagnosis of the PMB canal orifice from a perforation site. [ABSTRACT FROM AUTHOR]

Copyright of Dental Press Journal of Orthodontics is the property of Dental Press International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Artificial tooth movement may compromise the occlusion of complete (or implant-supported complete) over-dentures. This movement can lead to traumatic occlusion that may need to be corrected because the planned harmonious occlusion is lost, mainly when anatomic artificial teeth are utilized. Purpose: The study was conducted to evaluate the effect of the combination of gypsum plaster and laboratory silicon on the artificial teeth movement during the flasking procedure using radiographic imaging of intra-flask changes. Methods: In the current study, 90 identical mandibular complete dentures were fabricated and divided into two groups according to the acrylic material used. Stainless-steel pieces (0.5-0.5) were placed in the (buccal and mesiobuccal) cusp tips of the first premolar and first molar on both sides. Each group was subdivided into three subgroups (n=15) representing different techniques of flasking. Radiographs were taken at three phases of the flasking procedure, before and after the second investment layer and after curing the acrylic. The anteroposterior and mediolateral factors were calculated, and the data were analyzed by the one-way analysis of variance (ANOVA) and Duncan's post hoc tests at P<0.05. Results: The anteroposterior factors of the groups had insignificant differences at all phases, and the mediolateral factors showed significant differences in the gypsum samples and total silicon samples. Conclusion: Anteroposterior movement of the artificial teeth was not changed due to bracing between the teeth, and a mixed silicon and plaster investing layer had the smallest teeth location changes during the packing and curing phases. [ABSTRACT FROM AUTHOR]

It is urgently necessary to clarify the effect of extraction of impacted mandibular third molar (IMTM) on the periodontal tissue of adjacent second molars (ASMs). In this study, the ASM periodontal condition and pathogenic microbes were assessed before IMTM extraction and at 1, 4, 8 and 12 weeks postoperatively. Based on the inclusion and exclusion criteria, our study revealed that IMTM extractions adversely affected distal － periodontal probing depth (dPPD), attachment loss (dAL), plaque index (dPLI) and bleeding on probing (dBOP) within 8 weeks, but these indices gradually normalize after 12 weeks. The subgingival pathogens near the ASMs distal surface, Porphyromonas and Pseudomonas , were significantly increased postoperatively. Moreover, relevance of ASMs clinical indices and subgingival microbes after IMTM extractions was found. In contrast to the situation in chronic periodontitis, the effects of IMTM extraction on dPPD, dAL, dPLI and dBOP of ASMs were mainly correlated with Pseudomonas. Additionally, while the IMTM extractions have adverse distal periodontal indices of ASMs within 8 weeks and increase subgingival pathogens, the modified triangular flap (MTF) had fewer distal periodontal indices and less Pseudomonas. Compared to the traditional envelope flap and triangular flap, the MTF benefits the periodontal health, which could be considered as the priority option for IMTM extractions. • Differing from the previous arguments about the pros and cons of tooth extraction, the time-dependent effect of IMTM extraction on ASMs periodontal condition was explored firstly. • Secondly, unlike chronic periodontitis dominated by P. gingivalis , the periodontal inflammatory markers of dPPD, dAL, dPLI and dBOP of ASMs after IMTM extraction were more correlated with Pseudomonas, which has never been found to perform this role. • Thirdly, the MTF operation had less distal periodontal indices and fewer Pseudomonas, which provides a less invasive surgical option for IMTM extraction. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to compare the effectiveness of three different instruments on cement loss, porosity and micro‐crack formation, which was not evaluated before, following scaling and root planning (SRP) using micro‐computed tomography (micro‐CT). Methods: In this experimental study, 30 single‐rooted extracted human teeth were used and divided into three groups. All the teeth were scanned with micro‐CT before and after SRP. Group 1: SRP was performed with Gracey curettes, Group 2: SRP was performed by using an ultrasonic device, and Group 3: SRP was performed by using diamond burs. Cement loss from the root surface, porosity, and micro‐crack formation in the root dentine were analysed. Micro‐CT is used for qualitative and quantitative analysis of samples. The obtained data were analysed statistically (p < 0.05). Results: Minimum cement loss following SRP was detected with ultrasonic scaler (26.98 mm3), whereas the highest was created by diamond burs (96.20 mm3) (p < 0.05). The total porosity values after SRP were 0.278%, 0.334% and 0.252% for Groups 1, 2 and 3, respectively. Although Group 3 had the least porosity values, there was no statistically significant difference between the groups. The highest micro‐crack formation was seen in Group 2 and the lowest was in Group 1 with a significant difference (p < 0.05). Conclusions: More cement loss was observed with diamond burs. Ultrasonic devices appear to be a viable alternative to instrumentation with curettes. However, ultrasonic devices should be used carefully because of micro‐crack formation since the micro‐crack resulting from instrumentation with hand instruments is the least of all. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this preliminary study was to determine the differences between planned and actual maxillary molar movements after the completion of treatment with an initial set of clear aligners including sequential maxillary molar distalization. Methods: The data records of 14 non-growing patients who completed orthodontic treatment with sequential maxillary molar distalization using clear aligners were retrospectively evaluated (n= 14, 4 males and 10 females, 33.61 ± 8.57 years). Data on planned tooth movements were obtained from ClinCheck software (ClinCheck Pro version 5.3). The amounts of actual tooth movements were obtained by performing superimposition of lateral cephalograms taken before and after treatment. The amounts of distal translation and tipping between planned and actual maxillary molar movements were compared with the paired Student's t-test. Results: The statistically significant differences between planned and actual translation movements of maxillary first and second molars were shown after completing treatment with the first series of aligners (p < 0.05). The average actual amount of molar distalization on maxillary first molars was less than the planned amount by 1.32 ± 0.42 mm. Similarly, the average actual amount of molar distalization on maxillary second molars was less than the planned amount by 1.57 ± 0.45 mm. The accuracy for molar distalization, namely, the percentage of actual distal translation to planned movement, was 40.11% for maxillary first molars and 35.39% for maxillary second molars. However, the difference between the planned and actual angulation movements was not significant (p > 0.05). Conslusions: In conclusion, the amounts of actual distal translation of maxillary molars through the utilization of clear aligners were significantly lower than planned. However, there were no statistically significant differences between the degrees of actual and planned molar angulation movement. [ABSTRACT FROM AUTHOR]

Dental caries remains the most prevalent chronic disease globally, and its management should adhere to the principles of minimal intervention dentistry. This study reports a series of successful cases involving the selective removal of carious tissue in permanent molars, with follow‐up periods of up to 21 years. Six permanent molars with severe and deep carious lesions were treated with selective caries removal and restored with high‐viscosity glass ionomer cement. Clinical examination revealed that the teeth were free from pain and sensitivity. Follow‐up assessments were conducted at 7 and 21 years posttreatment. Treatment success was defined by the absence of clinical and radiographic signs, symptoms of pulp alterations, and lesion arrest. Successful minimally invasive approaches were observed with selective removal of carious tissue and maintenance of pulp vitality for up to 21 years. [ABSTRACT FROM AUTHOR]

Background: High precision intra-oral scans, coupled with advanced software, enable virtual bracket removal (VBR) from digital models. VBR allows the delivery of retainers and clear aligners promptly following debonding, thus reducing the patients' appointments and minimizing the likelihood of tooth movement. The objective of this study was to compare the enamel surface before bonding and after VBR using three different Computer-aided design (CAD) software and to compare their accuracy. Methods: Maxillary scans of 20 participants starting orthodontic treatment were selected for inclusion in the study, who exhibited mild to moderate crowding and required bonding of brackets on the labial surface of permanent maxillary teeth (from the maxillary left first molar to the maxillary right first molar). Two intra-oral scans were conducted on the same day, before bonding and immediately after bonding using CEREC Omnicam (Sirona Dental Systems, Bensheim, Germany). The virtual removal of the brackets from the post-bonding models was performed using OrthoAnalyzer (3Shape, Copenhagen, Denmark), Meshmixer (Autodesk, San Rafael, Calif, USA), and EasyRx (LLC, Atlanta, GA, USA) software. The models that underwent VBR were superimposed on the pre-bonding models by Medit Link App (Medit, Seoul, South Korea) using surface-based registration. The changes in the enamel surface following VBR using the three software packages were quantified using the Medit Link App. Results: There was a significant difference among the 3Shape, Meshmixer, and EasyRx software in tooth surface change following VBR. Specifically, EasyRx exhibited lower levels of accuracy compared to the other two VBR software programs (p<.001, p<.001). A significant difference in enamel surface change was observed between tooth segments across all software groups, in both incisors and molars, with VBR of the molars exhibiting the lowest level of accuracy (3Shape p=.002, Meshmixer p<.001, EasyRx p<.001). Regarding the direction of tooth surface changes following VBR, it was observed that all three groups exhibited a significant increase in the percentage of inadequate bracket removal across all teeth segments. Conclusions: 3Shape and Meshmixer manual VBR software were found to be more accurate than EasyRx automated software, however, the differences were minimal and clinically insignificant. [ABSTRACT FROM AUTHOR]

Objectives: The lower second molar mostly has a C configuration and it is important to know the internal anatomy and classification to have a better clinical approach, so the objective was to evaluate the prevalence and types of C-shaped canals in permanent mandibular second molars by using cone beam computed tomography (CBCT). Materials and Methods: 150 CTHC images of mandibular second molars were used. The following was recorded: sex, presence of Cshaped canal, location, morphology and type of C configuration according to Fan's classification, which is divided into C1, C2, C3 (c and d), C4 and C5. The chi-square test was used to analyze the differences between groups (p=0.05, considered a statistically significant difference). Results: Of the 300 teeth evaluated, 12.6% had C-shaped canals. There were no statistically significant differences between C-shaped canals and sex. This configuration tends to appear bilaterally, however, when it appears unilaterally, we find it mostly on the right. At the level of the pulp chamber floor and middle third, C1 was the most frequent and at the apical level it was C4 for both parts (37 and 47). Conclusions: The prevalence of Cshaped canals is not high. Bilateral appearance is more common than unilateral. Fan's classification is a complement to Melton's, since it will help us understand in more detail the morphological changes of this configuration along the root. [ABSTRACT FROM AUTHOR]

Tooth position anomalies, influenced by both genetic and environmental factors, can significantly impact oral health and play a critical role in establishing proper occlusion. The aim of this study was to identify the most prevalent tooth position anomalies in first permanent molars among Romanian patients and to evaluate additional variables as well. This retrospective study utilized digital study models to identify all existing tooth position anomalies. The study included patients aged 12 to 40 years with complete permanent dentition. Axial changes (buccal tilting, oral tilting, mesial tilting, and distal tilting) as well as rotational changes (mesio-buccal rotation and disto-buccal rotation) were investigated. After applying the exclusion criteria, 103 patients remained in the study. Our findings revealed a notable prevalence of positional anomalies, with disto-buccal rotations being most common in upper molars (tooth 1.6–22.3%, tooth 2.6–31.1%) and oral tilting predominating in lower molars (tooth 3.6–6.8%, tooth 4.6–14.6%). Interestingly, neither gender nor malocclusion type significantly influenced the occurrence of tooth position anomalies. Symmetrical patterns in positional changes were observed, with patients having tooth position anomalies at 1.6 significantly more frequently associated with anomalies at 2.6. Similarly, anomalies at 3.6 were significantly more frequently associated with anomalies at 4.6. Additionally, for molars 2.6 and 3.6 on the left side, the differences were statistically significant, with patients having anomalies at 2.6 significantly more frequently associated with anomalies at 3.6. This pattern was not observed for the molars situated on the right side of the dental arches. While this study provides insights into positional anomalies in first permanent molars among the Romanian population, its retrospective design and focus on a specific demographic may limit generalizability. In conclusion, the study underscores the significant prevalence of positional anomalies in first permanent molars among adolescents and adults in Oradea, Romania. Early detection and targeted interventions are crucial to address these anomalies and improve orthodontic outcomes. Comprehensive assessment and treatment planning are essential to achieve optimal dental harmony and function. Further research is needed to elucidate the underlying factors contributing to these positional changes and their long-term impact on oral health and occlusal stability. [ABSTRACT FROM AUTHOR]

Key Clinical Message: This paper illustrated successful endodontic non‐surgical (re)treatments of molars and premolar with different taurodontic classifications and accompanied anomalies like C‐shape and extra root canals in otherwise healthy patients. Magnification with illumination besides active irrigation with NaOCl were the most helpful items in managing these cases. [ABSTRACT FROM AUTHOR]

Root canal anomalies can be challenging to treat. Classification systems provide a framework which helps the clinician in effective diagnosis and treatment planning, improves treatment precision, analyses the risk assessment and treatment outcome, helps in education and communication with peers and has research implications. With advancements in technology, the understanding of the complex anatomy of the root canal system is improving drastically. This review caters from the old to the most recent classification. The anomalies included are Palatogingival Groove, Dens Invaginatus, Dens Evaginatus, Talon's Cusp, C-Shaped Canals, Taurodontism, Root Fusions, Radix Entomolaris and Paramolaris, Maxillary molar and Maxillary premolar with extra root. This review highlights various classification systems for tooth anomalies which impact the endodontic treatment strategy. It provides a holistic perspective to the clinician such that management of such anomalies can be done effectively. [ABSTRACT FROM AUTHOR]

The prevalence of the middle mesial canal (MMC) is present in the mandibular first molar (MFM). This study evaluated the prevalence of missed middle mesial canals (MMMC) in the endodontically treated mandibular first molars (ETMFM) using histological and cone beam computed tomography (CBCT) study. 372 extracted MFM, ages 10-60, were divided into 2 groups according to gender. ETMFM included 24 samples. The teeth were viewed by a Carestream CBCT device, and then they were histologically prepared, sectioned, and viewed under a stereomicroscope. The images were evaluated for the presence of the canals, and the results were analyzed statistically by the fischer exact test. The comparison was considered statistically significant at p<0.05. The prevalence of the MMMC was 62.5% (15 teeth) of the examined teeth. Prevalence rates of MMMC according to gender were found to be higher in females, with no statistically significant difference. Fifteen teeth revealed the MMMC when viewed only histologically, and 10 teeth revealed the revealed the CBCT. The canal morphology of these canals was least seen in the coronal and apical areas of the root canal. The prevalence of MMMC using CBCT is 66.66%, while histologically, it was 100% of total MMMC samples. Clinically, many MMCs cannot be detected due to their small size, which cannot be seen radiographically. The prevalence rate of MMMC is high in ETMFM clinically and is considered a causative factor of the failure and extraction after the endodontic treatment in ETMFM. [ABSTRACT FROM AUTHOR]

Copyright of Turkiye Klinikleri Journal of Dental Sciences is the property of Turkiye Klinikleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Knowledge of tooth anatomy and its variations are essential for the success of endodontic treatment. Dilacerations represent developmental anomalies marked by sudden deviations in a tooth's longitudinal axis. Common causes of treatment failures in such cases are primarily related to procedural errors such as ledging, fractured instruments, canal blockages, zipping, and elbow creations. The current case series presents three such interesting cases of endodontic management of curved root canals in mandibular molars. [ABSTRACT FROM AUTHOR]

Understanding how epigenetic factors impact dental phenotypes can help refine the use of teeth for elucidating biological relationships among human populations. We explored relationships among crown size, principal cusp spacing, and accessory cusp expression in maxillary dental casts of nutritionally supplemented (n = 34) and non-supplemented (n = 39) individuals from Tezonteopan, Mexico. We hypothesized that the non-supplemented group would exhibit smaller molar crowns and reduced intercusp spacing. Since intercusp spacing is thought to be more sensitive to epigenetic influences than crown size, we predicted that the supplemented and non-supplemented groups would differ more in the former than the latter. Previous work suggests that molar accessory cusp expression may be elevated under conditions of stress. We therefore expected evidence of greater Carabelli and Cusp 5 trait expression in the non-supplemented group. We further hypothesized that anterior teeth would be affected by nutritional stress during development, with the non-supplemented group having smaller anterior tooth crowns and therefore limited space to form the tuberculum dentale. Finally, we tested whether the presence of molar accessory traits followed predictions of the Patterning Cascade Model of tooth morphogenesis in the entire sample. Our results supported the expectation that cusp spacing would differ more than molar crown size between the two groups. Carabelli trait showed little evidence of frequency differences between groups, but some evidence of greater trait scores in the non-supplemented group. The non-supplemented group also showed evidence of greater Cusp 5 frequency and expression. In the central incisors and canines, there was strong evidence for smaller crown sizes and reduced tuberculum dentale frequency in the non-supplemented group. With both groups pooled together, there was strong evidence of closer mesiodistal distances among principal cusps in molars with accessory cusps, a finding that is consistent with the PCM. Overall, our findings suggest that nutritional stress may affect accessory cusp expression. [ABSTRACT FROM AUTHOR]

Objectives The biomechanics in achieving molar distalization may differ between fixed appliances and clear aligners in the control of tooth movement. The objective of this study was to compare the treatment effects between clear aligners (CA) and fixed appliances (FA) in patients treated with miniscrew-assisted molar distalization. Methods The sample consisted of 46 subjects with mild-to-moderate crowding. A total of 22 patients treated with clear aligners (age, 25.66 ± 6.11 years old) and 24 patients treated with fixed appliances (age, 24.04 ± 4.95 years old) for miniscrew-assisted molar distalization were included in this study. The dental and skeletal changes were evaluated by the pre- and post-treatment lateral cephalograms. Results Significant changes were found with the vertical variables SN-OP angle (2.24 ± 3.22°, P  < .05) and SN-MP angle (0.73 ± 1.15°, P  < .05) for the FA group when compared with the CA group (SN-OP angle 0.41 ± 2.26° and SN-MP angle −0.21 ± 1.38°, P  > .05). Both treatment groups achieved a 2–3 mm. molar distalization with significant intrusion of the upper molars. The CA group showed significantly less distal tipping of molars (U6^PP angle −2.29 ± 3.29° and L6^MP angle −2.92 ± 2.49°, P  < .05) compared to the FA group (−5.24 ± 4.28° and −5.53 ± 5.03°, P  < .05). In addition, significant retraction and lingual inclination of the upper and lower incisors were found in both groups. Limitations The changes of tooth position were evaluated by 2D lateral cephalograms, not 3D measurements. Conclusions Compared to fixed appliances, clear aligners seemed to have better control of vertical dimension and distal tipping of molars in patients treated with miniscrew-assisted molar distalization. [ABSTRACT FROM AUTHOR]

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Purpose: Preoperative identification of the intraosseous posterior superior alveolar artery (PSAA) is critical when planning sinus surgery. This study was conducted to determine the distance between the cementoenamel junction and the PSAA, as well as to identify factors influencing the detection of the PSAA on cone-beam computed tomography (CBCT). Materials and Methods: In total, 254 CBCT scans of maxillary sinuses, acquired with 2 different scanners, were examined to identify the PSAA. The distance from the cementoenamel junction (CEJ) to the PSAA was recorded at each maxillary posterior tooth position. Binomial logistic regression and multiple linear regression were employed to evaluate the effects of scanner type, CBCT parameters, sex, and age on PSAA detection and CEJ-PSAA distance, respectively. P-values less than 0.05 were considered to indicate statistical significance. Results: The mean CEJ-PSAA distances at the second molar, first molar, second premolar, and first premolar positions were 17.0±4.0 mm, 21.8±4.1 mm, 19.5±4.7 mm, and 19.9±4.9 mm for scanner 1, respectively, and 17.3±3.5 mm, 16.9±4.3 mm, 18.5±4.1 mm, and 18.4±4.3 mm for scanner 2. No independent variable significantly influenced PSAA detection. However, tooth position (b= -0.67, P<0.05) and scanner type (b= -1.3, P<0.05) were significant predictors of CEJ-PSAA distance. Conclusion: CBCT-based estimates of CEJ-PSAA distance were comparable to those obtained in previous studies involving cadavers, CT, and CBCT. The type of CBCT scanner may slightly influence this measurement. No independent variable significantly impacted PSAA detection. [ABSTRACT FROM AUTHOR]

This retrospective study evaluated the effect of combined periodontal-orthodontic treatment in terms of clinical, radiographic, and patient-reported outcomes in 40 stage IV periodontitis patients with advanced attachment loss and pathologic migration of anterior teeth. Full-mouth periodontal parameters were recorded at baseline (after diagnosis; T0), at the end of active periodontal therapy (APT; T1), at completion of orthodontic tooth movement (OTM; T2), and at the last supportive periodontal care (SPC) visit (T3). Radiographic analysis was performed at T0, T2, and T3. A total of 115 teeth were lost during APT, including 5 molars at T2 (used as orthodontic anchorage) and 10 premolars at T3 (due to root fracture). All anterior migrated teeth were in function at T3 (mean duration: 9.5 years). Significant mean probing pocket depth reduction (1.5 ± 1.1 mm) and attachment level gain (0.9 ± 1.0 mm) were observed after APT, whereas OTM and SPC were associated with furthering small changes. The alveolar bone level at T3 was slightly increased from T0 values. Patient-reported outcome measurements significantly improved in terms of esthetics and masticatory function. OTM should be considered an essential part of the comprehensive treatment plan to change the prognosis of severely compromised teeth in stage IV periodontitis patients. [ABSTRACT FROM AUTHOR]

Clear aligners are employed daily for the treatment of several malocclusions. Previous clinical studies indicated low accuracy for the correction of tooth rotations. The aim of this study was to evaluate the predictability of tooth rotations with clear aligners. The sample comprised 390 teeth (190 mandibular; 200 maxillary), measured from the virtual models of 45 participants (21 men, 24 women; mean age: 29.2 ± 6.6 years old). For each patient, pre-treatment (T0) digital dental models (STL files), virtual plan (T1) and post-treatment digital dental models (T2) of both the mandibular and maxillary arches were imported onto Geomagic Control X, a 3D metrology software which allows angular measurements. Rotations were calculated by defining reproducible vectors for all teeth in each STL file and superimposing both T0 with T1 to determine the prescribed rotation, and T0 with T2 to determine the achieved rotation. Prescribed and achieved rotations were compared to assess movement's accuracy. The Wilcoxon signed-rank test and paired t-test were used to assess differences between the prescribed and achieved movements (P < 0.05). The overall predictability of rotational movement was 78.6% for the mandibular arch and 75.0% for the maxillary arch. Second molar accuracy was the lowest in both arches. Clear aligners were not able to achieve 100% of the planned movements. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to establish a model combining MRI volume measurements from the 1st, 2nd and 3rd molars for age prediction in sub-adults and compare the age prediction performance of different combinations of all three molars, internally in the study cohort. Material and method: We examined 99 volunteers using a 1.5 T MR scanner with a customized high-resolution single T2 sequence. Segmentation was performed using SliceOmatic (Tomovision©). Age prediction was based on the tooth tissue ratio (high signal soft tissue + low signal soft tissue)/total. The model included three correlation parameters to account for statistical dependence between the molars. Age prediction performance of different combinations of teeth for the three molars was assessed using interquartile range (IQR). Results: We included data from the 1st molars from 87 participants (F/M 59/28), 2nd molars from 93 (F/M 60/33) and 3rd molars from 67 (F/M 45/22). The age range was 14–24 years with a median age of 18 years. The model with the best age prediction performance (smallest IQR) was 46–47-18 (lower right 1st and 2nd and upper right 3rd molar) in males. The estimated correlation between the different molars was 0.620 (46 vs. 47), 0.430 (46 vs. 18), and 0.598 (47 vs. 18). IQR was the smallest in tooth combinations including a 3rd molar. Conclusion: We have established a model for combining tissue volume measurements from the 1st, 2nd and 3rd molars for age prediction in sub-adults. The prediction performance was mostly driven by the 3rd molars. All combinations involving the 3rd molar performed well. [ABSTRACT FROM AUTHOR]

This study evaluated the stress distribution on an implant-supported zirconia crown of a mandibular first molar subjected to oblique loading by occlusal contact with the natural maxillary first molar by using the 3D finite element method. Two virtual models were made to simulate the following situations: (1) occlusion between maxillary and mandibular natural first molars; (2) occlusion between zirconia implant-supported ceramic crown on a mandibular first molar and maxillary natural first molar. The models were designed virtually in a modeling program or CAD (Computer Aided Design) (Rhinoceros). An oblique load of 100 N was uniformly applied to the zirconia framework of the crown. The results were obtained by the Von Mises criterion of stress distribution. Replacement of the mandibular tooth by an implant caused a slight increase in stress on portions of the maxillary tooth roots. The crown of the maxillary model in occlusion with natural antagonist tooth showed 12% less stress when compared with the maxillary (model in occlusion with the) implant-supported crown. The mandibular crown of the implant show 35% more stress when compared with the mandibular antagonist crown on the natural tooth. The presence of the implant to replace the mandibular tooth increased the stresses on the maxillary tooth, especially in the region of the mesial and distal buccal roots. [ABSTRACT FROM AUTHOR]

Background: The success of root canal therapy in endodontics is heavily dependent on identifying a second mesiobuccal canal (MB2) in permanent maxillary molars. A comprehensive understanding of internal anatomy, particularly the recognition of MB2, is crucial for the effective treatment of this commonly encountered tooth. This study aimed to investigate the prevalence and occurrence of the second mesiobuccal canal in permanent maxillary first and second molars. Methods: This cross-sectional study that was conducted at the Department of Conservative Dentistry & Endodontics, Military Dental Centre Dhaka, Bangladesh from January 2018 to December 2018. The analysis involved a total of 200 maxillary first molars and 200 maxillary second molars. In the initial phase for both groups, teeth were examined with the naked eye followed by microscopic assessment. Data analysis was conducted with MS Office tools. Results: In naked eye observation, the frequency of MB2 canals in the first molar teeth was found 64%, and in the second molar teeth it was found 56%. On the other hand, by microscopic assessment, the frequency of MB2 canals in the first molar teeth was found 96%, and in the second molar teeth, it was found 84%. Conclusion: The occurrence of the second mesiobuccal canal (MB2) in permanent maxillary first molars is more common than in the second molars. Microscopic assessment proves to be more effective than naked eye assessment for detecting the presence of MB2 in both maxillary first and second molars. [ABSTRACT FROM AUTHOR]

Introduction: Intense histological research has been conducted on human bone and teeth for a long period of time. Histological evaluation of these highly mineralised tissues demands a thorough decalcification process using different chemical agents, which might alter some aspects of tissue architecture and staining properties. Aim: To assess the impact of four decalcifying agents on rat teeth and bone, focusing on the rate of decalcification, staining effectiveness, and tissue structure preservation. Materials and Methods: An in-vitro animal study was conducted in the Department of Oral Diagnosis at the College of Dentistry, University of Baghdad, Bab Almoaadim, Baghdad, Iraq from October 2022 to March 2023. Four decalcification agents, namely 10% Neutral Ethylenediaminetetraacetic Acid (EDTA), 10% formic acid, 3% nitric acid, and 5% nitric acid, were used to decalcify 24 molar teeth with their surrounding alveolar bone obtained from healthy male rats, which were randomly divided into four groups, each group consisting of six teeth. The decalcified sections underwent regular processing, and staining was performed using Haematoxylin and Eosin (H&E). Grading was conducted after two separate observers examined the stained sections under a light microscope. Data were presented using Mean±Standard Deviation (SD), number, and percentage. A one-way Analysis of Variance (ANOVA) (F-test) was used to compare the decalcification times within groups. Several group comparisons, including categorical data, were examined using the Chi-square test. Results: Nitric acids (3% and 5%) exhibited the fastest decalcification with a mean value of (2±0.89) days, while Formic acid required (3.5±0.54) days, and EDTA was the slowest, with (19±1.09) days. These differences in decalcification time were found to be statistically significant (p<0.00001). Formic acid 10% demonstrated superior tissue preservation and staining quality, with excellent staining results, minimal dentin-pulp separation, and preservation of pulp zones, cementum, and osteoblasts. In contrast, nitric acid 5% resulted in severe dentinpulp separation, absence of pulp zones, absence of osteoblast, and significant osteocyte retraction. Statistical significance was observed across all agents for dentin-pulp separation, pulp organisation, cementum destruction, Periodontal Ligament (PDL) separation, and osteocyte retraction (p-values of 0.004, 0.02, 0.02, 0.04, and 0.03, respectively). Conclusion: Consequently, 10% formic acid emerged as the most efficient decalcifying solution, ensuring rapid decalcification with favourable staining intensity and tissue architecture. [ABSTRACT FROM AUTHOR]

Purpose: The study aimed to evaluate temporary fillings using Biodentine™ in asymptomatic deep carious lesions after 12, 24, and 36 months in school children from the remote village of Kerung, Nepal. Methods: From November 2018 to November 2019, 91 temporary fillings were placed using Biodentine™ (a hydraulic calcium silicate cement) in permanent molars with deep carious lesions of schoolchildren in the remote district of Kerung, Nepal. These restorations were performed after selective caries removal in a non-dental setting with hand instruments and cotton roll isolation, as electric motors and saliva ejection systems were unavailable. In total, 78 single-surface and 13 multi-surface fillings were placed. Clinical and radiographic follow-up periods encompassed 12, 21, and 33 months, respectively. Results: After 12 months, all single-surface fillings (100%) survived, whilst all multi-surface fillings were partially or entirely lost. The survival rate of single-surface restorations after 21 and 33 months was 67.6% and 50%, respectively. Radiographically, no pathology was observed. Conclusion: This study showed that Biodentine could be used in deep carious lesions as a temporary filling in single-surface lesions for at least up to 1 year and in a substantial number of cases for up to 21 and 33 months. [ABSTRACT FROM AUTHOR]

Background: The relationship between the maxillary sinus (MS) and the root apices of posterior teeth is of significant clinical relevance as it influences the diagnosis and treatment planning when operating in the posterior areas of the maxilla. The aim of this study, therefore, is to assess this anatomic relationship and evaluate the propensity of roots of posterior maxillary teeth to be intruded into the MS space using cone-beam computed tomography (CBCT) scanning. Materials and Methods: One thousand CBCT scans of patients, aged 20 years or above, were analyzed in the study. The distance from the MS floor to the root apices of the posterior teeth was measured and the relationship between the MS and the posterior teeth roots were recorded, based on Kwak's and Didilescu's classification. Results: Based on Kwak's classification, type I configuration was frequently observed in the maxillary posterior teeth, followed by type II. Based on Didilescu's classification, the longest distance, among premolars, was observed between the palatal root of the left 1st premolar and MS, i.e., 8.2467 mm. Among molars, the longest distance was observed between mesiobuccal root of the right first molar and MS, i.e., 5.8966 mm. The shortest distance, among premolars, was observed between the buccal root of the left second premolar and MS, i.e., 3.5500 mm, and among molars, the shortest distance was between the mesiobuccal root of the left second molar and MS, i.e., 1.3556 mm. Conclusion: From the present study, it may be concluded that, among the central Indian population, mesiobuccal root of the second molars and buccal root of the second premolars show the closest proximity to the MS floor. Therefore, any surgical or endodontic intervention in the vicinity of these roots must be performed with utmost care. [ABSTRACT FROM AUTHOR]

Introduction: We aimed to evaluate the effects of 38% silver diamine fluoride (SDF) application on the progression of secondary caries (SC) around resin-based composite (RBC) restoration margins in extracted human primary molars compared to 2.5% fluoride varnish (NaF) with hydroxyapatite and no intervention. Methods: Standardized box-shaped cavities were prepared on 30 primary teeth and restored with RBC restorations. The teeth were thermo-cycled and then immersed in a demineralizing solution for 10 days. The baseline volumes of the demineralized lesions were measured using Micro-CT (first evaluation). Next, the teeth were randomly divided into three equal groups of 10 teeth: the experimental group (38% SDF), the positive control group (2.5% NaF varnish with hydroxyapatite), and the negative control group (no intervention). All teeth were immersed again in the demineralizing solution for 10 days, followed by a second micro-CT evaluation. Results: There was a statistically significant difference in the rate of change of demineralization areas between the three groups (p < 0.001). The SDF group showed the least change in the mean volume of the demineralization area between the baseline and after the second exposure (3.4 ±0.94 mm³) compared to NaF (4.85 ± 1.97 mm³) and the negative control groups (8.78 ± 2.03 mm³). Conclusion: SDF was effective in managing primary molars with SC around resin-based composite restorations. [ABSTRACT FROM AUTHOR]

Introduction: Molar intrusion has always been a complicated and difficult treatment modality. Posterior teeth that are supra-erupted due to the early loss of their antagonists are commonly seen in adults that have limited or no access to dentistry during childhood and adolescence. Severely over-erupted molars or entire posterior segments pose a great challenge to the treating orthodontist. With regard to intruding posterior teeth, molar intrusion is a treatment option for patients with Anterior Open Bite (AOB); a malocclusion often characterized by the overeruption of the posterior teeth or/and under eruption of the anterior teeth. Aim: To compile and summarize the existing and advanced molar intrusive techniques and appliances with respect to their advantages and disadvantages, and their possible clinical effectiveness. Conclusion: We can utilize skeletal anchorage and surgically assisted techniques for efficient intrusion with limited side effects. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Root resection is performed to create a maintainable furcation area in teeth with advanced periodontitis. However, the long‐term feasibility of this treatment remains controversial. We present a case in which distal root resection in a maxillary molar successfully preserved the form and function of the dentition for approximately 14 years. [ABSTRACT FROM AUTHOR]

This article discusses the challenges and management of severe alveolar defects and periodontally compromised teeth in the esthetic zone. It highlights the importance of an interdisciplinary approach, including orthodontics, in complex cases. The article presents case studies that demonstrate the use of orthodontic movement and extrusion to improve esthetics and bone and soft tissue architecture. It emphasizes the potential for successful outcomes with careful treatment planning and patient commitment. The article also discusses the effectiveness of orthodontic extrusion in improving the stability and esthetics of periodontally compromised teeth, as well as its benefits in esthetic rehabilitation cases involving severe alveolar defects. It underscores the importance of an interdisciplinary approach and careful case management for successful outcomes. [Extracted from the article]

Objective: Proper and conservative endodontic access cavity preparation is a crucial step in performing a successful root canal treatment that ensures a long-term prognosis. This study aimed to evaluate the intercuspal and interorifice length of maxillary first and second molars using cone beam computed tomography (CBCT). Methods: The CBCT scans of 400 mature and intact maxillary first and second molars (16, 17, 26, and 27) were evaluated. The measured variables included the distances between the buccal cusps (intercuspal distance) and buccal orifices (interorifice distance), the interorifice/intercuspal ratio, and the angle at the intersection of interorifice and intercuspal lines. The variables were compared between different teeth and between male and female patients. Results: The interorifice and intercuspal distances were significantly greater in males compared to females (P<0.05), except for the intercuspal distance in the left maxillary second molar (P=0.056). There was a statistically significant difference concerning the angle formed between the interorifice and intercuspal lines among tooth numbers 26 and 27 (P=0.044). The interorifice/intercuspal ratio was significantly different between the maxillary first and second molars on the right (P=0.006) and left sides (P<0.001). Conclusions: The angle formed between the intercuspal and interorifice distances and the interorifice/ intercuspal ratio was greater in the maxillary first molars compared to the second molars. Moreover, males generally had larger internal and external anatomical features than females. Hence, when preparing a conservative access cavity in maxillary molars, clinicians are advised to consider both the external tooth anatomy and the patient's gender as important factors. [ABSTRACT FROM AUTHOR]

Purpose: The aim was to assess the effect of span lengths and total occlusal convergence (TOC) on the accuracy of intraoral scanners. Materials and methods: Two typodont acrylic teeth models were prepared to receive fixed dental prostheses with three different span lengths. Span 1: between maxillary canines; span 2: between maxillary second premolars; and span 3: between maxillary second molars. In the first model, prepared teeth had a TOC of 12°, whereas, in the second model, teeth had a TOC of 20°. Each model was scanned 10 times using 4 different intraoral scanners (Omnicam, Primescan, Trios 4, and Medit i500). The STL files from the scans were compared to the reference models (trueness) and within each test group (precision) using a 3D comparison software. Data were then statistically analyzed. Results: Regarding trueness, no significant differences were found among Primescan (32.58 ± 13.08), Trios 4 (32.33 ± 12.19), and Medit i500 (32.26 ± 9.57). However, all showed significantly better trueness than Omnicam (35.70 ± 8.35) (p < 0.001). The highest values were found in scans between the second molars (47.42 ± 3.94), followed by scans between second premolars (28.42 ± 3.78), and the highest trueness was found in scans between the canines (23.80 ± 3.85). For TOC, 12° had a significantly higher value than 20° (p < 0.001). Regarding precision, the highest values were found with Omnicam (29.84 ± 3.89), followed by Medit i500 (28.04 ± 2.94), then Trios 4 (25.64 ± 3.11), and Primescan (24.69 ± 5.25). The highest values and least precision were found in scans between the second molars (28.97 ± 5.27) and scans between second premolars (27.59 ± 3.97), whereas the highest precision was found in scans between the canines (24.60 ± 2.04). For TOC, 12° had significantly higher values than 20° (p < 0.001). Conclusions: Intraoral scans are directly affected by scanner type, TOC, and scan spans. All tested scanners showed clinically acceptable results even for long‐span restorations. [ABSTRACT FROM AUTHOR]

(1) Background: The objective of this study was to assess which digitization method produces the biggest deviation in the 3D images of tooth size from plaster models made using alginate impressions, which are considered the gold standard in orthodontics. (2) Methods: The sample used in this study included 30 subjects (10 males and 20 females). Measurements were made on four types of models: (1) digital models obtained through intraoral scanning and digitized models of plaster cast made from (2) alginate impressions, (3) silicone impressions, and (4) conventional plaster models. Mesio-distal (MD) and buccal/labial–lingual/palatal (BL) dimensions were measured on the reference teeth of the right side of the jaw (central incisor, canine, first premolar, and first molar). Comparisons of tooth size between the methods were conducted using a repeated measurement analysis of variance and the Friedman test, while the intraclass correlation coefficient was used to determine agreement between the different methods. (3) Results: The results showed a similar level of agreement between the conventional and digital models in both jaws and the anterior, middle, and posterior segments. Better agreement was found for the MD measurements (r = 0.337–0.798; p ≤ 0.05) compared to the BL measurements (r = 0.016–0.542), with a smaller mean difference for MD (0.001–0.50 mm) compared to BL (0.02–1.48 mm) and a smaller measurement error for MD (0.20–0.39) compared to BL (0.38–0.89). There was more frequently a better level of agreement between 3D images than measurements made using a digital caliper on the plaster models with 3D images. (4) Conclusions: The differences in measurements between the digital models and conventional plaster models were small and clinically acceptable. [ABSTRACT FROM AUTHOR]

Introduction: In vitro fracture resistance of extracted mandibular molars treated with various access cavity designs, including traditional endodontic cavity (TradAC), conservative/contracted endodontic cavity (ConsAC), ninja endodontic cavity (UltraAC), truss endodontic cavity (TrussAC), caries-driven access cavity (CariesAC), and intact teeth, is the focus of this study. Materials and Methods: Six groups of 20 mandibular molars, totaling 120, were used in the investigation. While the other five groups underwent various access cavity preparations, chemomechanical preparation, and obturation procedures before being repaired with composite resin, Group 1 was left unaltered (the control). A 6 mm round head tip was used to apply the fracture force, which was measured in newtons, at a crosshead speed of 1 mm/min until fracture developed. Results: According to the current study, the intact control group had the maximum fracture resistance. The access cavity groups' mean values were maximum in CariesAC followed by ConsAC, TrussAC, UltraAC, and TraditonalAC respectively. Conclusion: While among the four minimally invasive designs, CariesAC showed a higher fracture resistance despite the results being statistically insignificant, TradAC had a significantly lower resistance than other conservative access cavity designs. [ABSTRACT FROM AUTHOR]

Odontology is the study of dental disease and structure. The human jaw consists of 32 teeth divided into four categories: incisors, canines, premolars, and molars. Every human has two sets of teeth in their life, a set of temporary teeth and a set of permanent teeth. To detect issues in the jaw, the dentist usually suggests scans such as OPG, CBCT, or CTs. OPG is a panoramic X-ray of the upper and lower jaws, whereas CBCT is a medical imaging procedure that uses divergent X-ray computed tomography. While OPG X-rays are generally preferred by dentists since they do not leave any radiation on the patient's anatomical tissues and are effective, easy, and quicker to analyze, CT scan images offer more detailed information than ordinary Xrays. In this paper, we'll go over many methods and models that other researchers in the same field have used to determine a person's age just by looking at scans or X-rays. The radiographs can also be used to identify other patterns, such as missing teeth, impacted teeth, the contour of the jaw, and the growth of the molar teeth. Some of these are also very important in the age estimation procedure. [ABSTRACT FROM AUTHOR]

Serially homologous elements pose an identification problem in fragmentary records, particularly those of vertebrate fossils. Examples include individual vertebrae in the vertebral column and teeth in a tooth row. Until an isolated element can be accurately attributed to a specific position within its series, multiple lines of ecological and evolutionary research cannot be conducted. However, varying levels of differentiability between loci, and varying patterns of differentiation across clades, make it impossible to develop a single set of diagnostic traits for any particular set of serial homologues, particularly mammalian molars. Here, we test the utility of a set of classification criteria for distinguishing molar tooth positions of hyraxes (Mammalia, Afrotheria, Hyracoidea), which have been considered indistinguishable in previous taxonomic studies. As part of the test we evaluate the degree to which between-locus variation is conservative in this taxon, which would strengthen the predictive power of proposed traits even in cases where species identity is unknown. Suitable tests for hypotheses of conservatism in categorical traits did not exist, to our knowledge, and we therefore explored the behavior of a previously developed metrics, Borges et al.’s δ, to assess conservatism in contrast to phylogenetic signal produced by Brownian motion. This metric shows some promise but the nature of resulting distributions makes tests difficult to interpret, indicating a line of potential future methods improvement. We used a linear morphometric characterization of shape to validate the candidate traits. In the case of hyracoid molars, relatively simple ratios of linear measurements have strong discriminatory power despite evolutionary variation in between-locus differences. Overall, new or understudied taxa are likely to have lower molar loci differentiable by their relative length and talonid vs. trigonid width. [ABSTRACT FROM AUTHOR]

Introduction: Nonmetric dental traits have a crucial role in ethnic classification of populationsthat help in forensic racial identification. Many studies have demonstrated the differencesin the expression and frequency of dental traits between various ethnic groupsfor ancestry determination in the context of forensic dental anthropology. The present study is an attempt to assess the frequency and variation in nonmetric traits for establishing ethnicity in the Vidarbha subpopulation. Aim: The aim of the study was to assess the frequency and variation of nonmetric traits in permanent teeth for establishing ethnicity in the Vidarbha subpopulation. Materials and Methods: Participants of the Vidarbha subpopulation were selected by random sampling method. Molars, premolars, and incisors were evaluated for frequency of nonmetric traits, and variations were graded according to Dentoanthropological System of State University of Arizona criteria. Descriptive statistics, Chi-square test, and Student’s t-test were used for analysis of data. Results: The most common occlusal morphology in mandibular first and second molar was 5 cusp and 4 cusp, respectively, with the “+” groove pattern. Cusp 3 and cusp 4 were observed frequently in the maxillary molars. One lingual cusp was most commonly seen in mandibular premolars show while incisors showed faint shoveling. Conclusion: Our study concludes that nonmetric traits were present and showed variation in permanent maxillary and mandibular teeth among the Vidarbha subpopulation. Cusp 5 and Cusp 4 in first and second mandibular molars, respectively, groove pattern “+” and grade 1 protostylid were the most frequent grades observed in permanent mandibular molars. One lingual cusp was most commonly seen in mandibular premolars and faint shoveling was a notable feature in incisors of this population. [ABSTRACT FROM AUTHOR]

The article informs about the determination of optimal settings for reconstructing buccal surfaces using the virtual bracket removal (VBR) technique, evaluating five settings from three commonly used computer-aided design (CAD) systems. Topics include the VBR protocol, the prevalence of root mean squares (RMSs) below the clinically acceptable limit, and the finding that G1 performed best for most tooth types in terms of accuracy.

The article informs about a systematic review and meta-analysis examining the role of mandibular third molars in late crowding of lower anterior teeth in patients with or without previous orthodontic treatment. Topic include the study reveals that the presence of lower third molars may contribute to mandibular crowding and lower arch constriction, emphasizing the need for further high-quality research to clarify their impact.

Purpose The study was directed to evaluate the antibacterial effect of ozone versus chlorhexidine gel for disinfection of cavitated carious lesions in young permanent teeth. Patients and methods Forty young permanent molars out of 20 children were allocated into two groups in a randomized technique according to the material used for cavity disinfection either ozone or chlorhexidine gel. Each child had two bilateral vital cavitated class I carious lesions in young permanent first molars. Dentin samples from deep caries lesions were collected before additionally after application of either ozone or chlorhexidine gel and cultured into freshly prepared appropriate media for microbiological examination. Results There were statistically significant decrease in both Streptococcus mutans and Lactobacillus bacterial count after application of either ozone or chlorhexidine gel in both groups. Conclusion Application of ozone or chlorhexidine gel as cavity disinfectant in deep carious lesions after incomplete dentin caries removal provide an obvious antibacterial effect reducing S. mutans and Lactobacillus counts. [ABSTRACT FROM AUTHOR]