Search Results (179)

Primary teeth play a crucial role in a child’s development, particularly in maintaining space for permanent teeth. The premature loss of a primary tooth can lead to orthodontic issues, making the use of space maintainers essential to ensure proper growth and development of permanent teeth. To preserve space, the fabrication of a space maintainer is necessary. Since conventional space maintainers do not restore masticatory function, this study presents an innovative solution for space preservation following the extraction of the first primary molar through the design of the functional space maintainer KOS&MET (Key Orthodontic System and Materials Enhanced Therapy). The space maintainer was designed using the 3Shape Dental Designer 2023 version software tool and manufactured via additive 3D printing, utilizing a metal alloy with high resistance to masticatory forces. The crown is supported by the primary canine, while an intraoral window is created to monitor the eruption of the successor tooth. This design does not interfere with occlusion and enables bilateral chewing. Masticatory performance was assessed using two-color chewing gum, and the results showed improvement after cementing the space maintainer. This innovative approach not only preserves space for permanent teeth but also enhances masticatory function, contributing to the proper growth and development of the jaws and teeth. Full article

Background/Objectives: Among the paranasal sinuses, the maxillary antrum holds unique clinical relevance due to its proximity to the alveolar process of the maxilla, which houses the teeth. This study aimed to evaluate the position of the root apices of the maxillary canines and posterior teeth relative to the maxillary sinus floor in Romanian subjects. Methods: Data for the study were retrospectively obtained from cone-beam computed tomography (CBCT) scans. The evaluation considered the pattern of proximity to the sinus floor for each tooth type, comparisons of the sinus relationships of teeth within the same dental hemiarch, as well as those of homologous teeth, and variation in root-to-sinus distance in relation to sex and age. Nonparametric tests were used for statistical analysis, and multiple comparisons were performed using Bonferroni post hoc correction. Results: The study included 70 individuals aged 20 to 60 years. The distance to the sinus floor decreased progressively from the first premolar to the second molar, with median values of 3.68 mm (first premolar), 1.45 mm (second premolar), 0.50 mm (first molar), and 0.34 mm (second molar) (p < 0.01). Stronger correlations were observed between adjacent teeth than between non-adjacent ones. The distances to the sinus floor were greater on the right side compared to the left; however, these differences were not statistically significant (p > 0.05 for all teeth). Concordance between left and right dental hemiarches regarding the closest tooth to the sinus floor was found in 70% of cases (n = 49), most frequently involving the second molars (n = 38; 54.3%). On average, the distance from the sinus floor was smaller in males compared to females, with statistically significant differences observed only for the second molar. Increased age was associated with a greater distance to the sinus floor. Conclusions: Of all the teeth investigated, the second molar showed the highest combined prevalence of penetrating and tangential relationships with the maxillary sinus. At the dental hemiarch level, the second molar was most frequently the closest tooth to the sinus floor, and in the majority of cases, at least one posterior tooth was located within 0.3 mm. Accurate preoperative assessment of tooth position relative to the sinus floor is essential when performing non-surgical or surgical root canal therapy and extractions of maxillary molars and premolars. CBCT provides essential three-dimensional imaging that improves diagnostic precision and supports safer treatment planning for procedures involving the posterior maxilla. Full article

Background/Objectives: Currently, clear aligners are preferred to conventional appliances, especially among adult patients. However, the use of aligners for treating maxillary constriction is still debated in the literature. Therefore, the purpose of this study was to assess maxillary dentoalveolar expansion following clear aligner therapy in adults using CBCT scans. Methods: The study sample encompassed 50 non-growing patients (27 females and 23 males) aged 20 to 42 undergoing clear aligner orthodontics without dental extractions or auxiliaries. Transverse linear distances were measured on initial and final CBCTs and, subsequently, analysed through paired t-test and ANOVA. We considered alveolar bone measurements and interdental widths measured at the buccal apices and cusps from canines to second molars. Results: The buccal alveolar ridge width showed the greatest expansion (1.01 ± 0.38 mm), followed by the palatal alveolar ridge and maxillary alveolar bone. Statistically significant improvements were observed for all interdental measurements. The most considerable changes occurred in the interpremolar cusp distances, while the least changes were seen in the intermolar apex distances. At the cusp level, the average interpremolar widths increased by 3.44 ± 0.22 mm for the first premolars and 3.14 ± 0.27 mm for the second ones. Conclusions: Clear aligner treatment can effectively manage a constricted maxillary arch. We found significant changes in the maxillary alveolar bone. Both inter-apex and inter-cusp widths increased in all teeth, with the highest values in the premolars. Moreover, the increases in interdental distances at both apex and cusp levels were related to tooth position. Full article

This study investigated the biomechanical effects of varying buccolingual beam widths in maxillary first premolar extraction spaces on canine distal bodily movement during clear aligner treatment. Using finite element analysis, four distinct models were constructed, incorporating beam designs with widths of 0 (edentulous), 1, 2, and 3 mm within the extraction space. Each model underwent a comprehensive 50-stage iterative simulation to evaluate canine displacement patterns, tipping, rotational movements, aligner deformation characteristics, and magnitudes of forces and moments applied to the canines throughout long-term tooth movement. Group 0 (no beam, 0 mm beam width) exhibited the greatest crown displacement and tipping angle. In contrast, Group 2 (2 mm beam width) most effectively reduced the final angulation of the canine, whereas Group 3 (3 mm beam width) was most effective in controlling unwanted rotation and minimizing deformation of the clear aligner. Furthermore, an increase in the beam width was associated with a trend of higher initial force and lower initial moment. Notably, relatively high levels of both force and moment were maintained during the later stages of the simulation, which is advantageous for sustained control of tooth movement. In conclusion, incorporating a beam of 2–3 mm width into the maxillary first premolar extraction space appears to be optimal for managing canine tipping and rotation while promoting bodily movement of the tooth. Full article

Background/Objectives: Routinely, clinicians planning the mechanics of orthodontic treatment for their patients do not take into account the inclinations of canine and lateral teeth. This is due to a lack of solid evidence in the area. Additionally, sound data is lacking on differences between tooth inclinations in patients presenting class II, subdivision 1 and class II, subdivision 2 relationships. This study is meant to investigate this matter. Methods: To conduct this study, cephalograms of 83 patients scheduled for orthodontic treatment were retrospectively selected from the records of the Department of Orthodontics at Wroclaw Medical University and analyzed. Patients were divided into three groups (class I, class II subdivision 1, class II subdivision 2). Inclinations of the long axes of canine and lateral teeth were measured in relation to the palatal plane. Results: We established that there exist statistically significant differences in inclination for some of the teeth assessed. Conclusions: Multiple correlations were found between tooth inclination and some cephalometric measurements, particularly the SNB angle. The canines and upper premolars undergo a natural distal tilt to compensate for the mandible’s retruded position. Clinicians planning treatment for skeletal class II patients should formulate treatment plans involving the distal tipping of lateral teeth with great care, as such patients may already exhibit distal inclinations of the lateral teeth. Patients with skeletal class II, division 2 may present greater demands in terms of proper orthodontic treatment mechanics compared to class II, division 1 patients. Full article

Permanent maxillary canines are key teeth from both functional and aesthetic perspectives. Tooth transposition, a rare anomaly where two permanent teeth exchange positions within the same quadrant, poses significant diagnostic and therapeutic challenges. This study aimed to identify the clinical conditions guiding the decision to correct or maintain maxillary canine transposition through a narrative review of the literature, complemented by a detailed clinical case. Following PRISMA guidelines, a search of PubMed, ScienceDirect, Cochrane Library, EBSCO, and Scopus databases (2014–May 2024) yielded 19 relevant studies. This review found no consensus on treatment protocols, reinforcing the need for individualized decision-making based on patient characteristics, anatomical constraints, and clinician expertise. While orthodontic correction can yield favorable aesthetic outcomes, it requires meticulous planning and biomechanical control. Conservative approaches are often indicated in early-diagnosed or anatomically complex cases. The clinical case illustrates the complexity of managing the transposition, specifically of the maxillary canine into the central incisor position, emphasizing the importance of early diagnosis, digital planning, and a multidisciplinary approach for functional and aesthetic success. Full article

Maxillary canines have a vital importance in the dental arches, both esthetically and functionally. They are the second most frequently impacted teeth, with palatal impaction being the most common. The purpose of the study was to evaluate the prevalence of palatally displaced canines (PDC) and their association with dental and skeletal anomalies. A retrospective analysis was conducted on 68 patients. A panoramic and a lateral cephalometric radiograph were performed to determine impaction type and patients’ dental and skeletal characteristics. The analysis grouped all PDC cases together and then subdivided them by location (right, left, or bilateral impaction). The most frequent PDC was right-side impaction. When all cases were grouped together, patients showed no family history of PDC (p < 0.05) or presence of dental anomalies (p < 0.05). No relation to skeletal class was observed, but a normodivergent growth pattern did show an association (p < 0.05). When different PDC types were analyzed separately, we observed a relationship with dental midline deviation (F = 17.04, p < 0.05), family history of PDC (F = 12.56, p < 0.05), and lateral incisors anomalies (F = 9.58, p < 0.05). Therefore, an association was found between PDC and dental anomalies when the types of impaction were analyzed separately and with the growth pattern when PDC cases were grouped together. Full article

Background/Objectives: Orthodontic temporary anchorage devices (TADs) in the lateral maxillary region are useful tools for successful orthodontic treatment. Radiological anatomical knowledge is crucial for the successful placement of TADs. The use of cone-beam computed tomography (CBCT) is essential for evaluating the relationship between the ideal placement point (IPP) and dental structures, particularly in cases with anatomical limitations. Accordingly, this study aims to assess the anatomical conditions for orthodontic mini-implant (MI) insertion in the posterior maxilla using CBCT as the gold standard. Methods: This retrospective study included 62 patients (37.1% male, 62.9% female) aged 11 to 50 years. CBCT scans (sagittal and axial cross-sections) were used to evaluate interdental bone characteristics in different regions. The evaluated regions were defined as follows: Region 1 (canine and first premolar), Region 2 (first and second premolars), Region 3 (second premolar and first molar), and Region 4 (first and second molars). All parameters were assessed at three predefined levels: A, B, and C, located 4, 3, and 2 mm, respectively, from the alveolar crest. At the aforementioned levels, we performed measurements, such as the interdental width (IDW) in the mesiodistal direction and buccopalatal depth (BPD). The last observation was the relationship between the ideal TAD placement point (IPP) and dental structures, such as contact points (CPs) and cusp tips (C1-cusp of mesial tooth, C2-cusp of distal tooth, in each region). Results: A statistically significant positive correlation was found between the IDW and BPD at Levels A, B, and C in Region 1, while a negative correlation was observed between the IDW and BPD at Level C in Region 2′. The highest percentages of IDW exceeding 3 mm were found in Region 4 at Level A (67.7%), followed by Region 1′ and 2′, both at Level A. The mean interdental width measured at each level on the right and left sides was highest at Level A, exceeding 3 mm, and the width decreased with each successive level. The mean BPD measured at each level on the right and left sides was also highest at Level A. Conclusions: This methodological approach could assist in ensuring precise and efficient implant insertion. Furthermore, it can be concluded that the safe zone for buccal and interdental mini-implant placement is located 4 mm from the alveolar crest at Level A. Also, the CBCT analysis algorithm may serve as a valuable tool for clinicians in determining optimal TAD placement in different dental regions. Full article

Background/Objectives: The growing demand for esthetic, less painful, and more comfortable orthodontic treatment has led to increasing use of aligner systems. Initially used for less complicated malocclusions, aligners are now being incorporated into complex treatment plans, including cases involving impacted teeth. While aligners are a popular alternative to traditional fixed appliances, they still have limitations. This study aims to evaluate the effectiveness of aligner-based orthodontic treatment in patients with impacted or significantly ectopic canines. Methods: This study was conducted in accordance with the PRISMA guidelines. The search terms used were as follows: ‘Clear Aligner’ OR ‘Invisalign’ AND ‘Impacted Canine’ OR ‘Impacted Tooth’ OR ‘Ectopic Tooth’ OR ‘Ectopic Canine.’ A total of 1101 records were identified, of which 170 articles underwent screening. Fifteen articles were assessed for eligibility, and ultimately six case reports and one three-dimensional finite element analysis (FEA) study were included for both quantitative and qualitative synthesis. Results: According to the studies, additional appliances are often required to achieve favorable outcomes when treating impacted canines with aligner systems. Temporary anchorage devices (TADs) were used in 5 out of 9 reported cases for canine traction into the dental arch. In three cases, TADs were combined with sectional wires implemented as cantilevers. Elastics were used in 6 out of 9 cases for traction to the opposite arch, and in 5 out of 9 cases as interarch elastics attached to the aligners. Interarch elastics were applied in various ways, either directly to the aligners or to primary canines using hidden buttons inside pontics or dovetail hooks. Elastics were also anchored to the lower arch with class II, class III, or cross-arch (criss-cross) mechanics. Conclusions: This review highlights the promising potential of aligner systems in the treatment of impacted canines. However, additional auxiliaries, such as TADs, sectional wires, or elastics remain nearly essential for initial canine traction. Aligner systems offer versatile treatment options, and the possibility of reduced treatment time represents a valuable area for future research. Full article

Purpose: This paper investigates the biomechanical effect of thermoformed aligners equipped with complementary biomechanical attachments (CBAs) on periodontal ligaments (PDLs) during the expansion process of the maxillary arch. The analysis was conducted using advanced simulations based on the finite element method (FEM). Methods: High-resolution 3D CAD models were created for four tooth types: canine, first premolar, second premolar, and first molar. Additional 3D models were developed for aligners, CBAs, and PDLs. These were integrated into a comprehensive FEM model to simulate clinical rehabilitation scenarios. Validation was achieved through comparative analysis with empirical medical data. Results: The FEM simulations revealed the following: for canine, the displacement was 0.134 mm with a maximum stress of 4.822 KPa in the amelocemental junction. For the first premolar, the displacement was 0.132 mm at a maximum stress of 3.273 KPa in the amelocemental junction. The second premolar had a displacement of 0.129 mm and a stress of 1.358 KPa at 1 mm from the amelocemental junction; and first molar had a displacement of 0.124 mm and a maximum stress of 2.440 KPa. Conclusions: The inclusion of CBAs significantly reduced tooth tipping during maxillary arch expansion. Among the models tested, the vestibular CBA demonstrated superior performance, delivering optimal tooth movement when combined with thermoformed aligners. Significance: FEM techniques provide a robust and cost-effective alternative to in vivo experimentation, offering precise and reliable insights into the biomechanical efficacy of CBAs in thermoformed aligners. This approach minimizes experimental variability and accelerates the evaluation of innovative orthodontic configurations. Full article

Objective: This study compared the tooth movement patterns of a power arm and a lever jig during mandibular canine retraction into a premolar extraction space using skeletal anchorage. Methods: A finite element model was developed based on anatomical structures. A mini-implant was placed between the mandibular second premolar and first molar, and canine retraction was simulated using a power arm and a lever jig. The lever jig’s vertical arm lengths were 6 mm, 8 mm, and 10 mm, corresponding to force application distances of 4.5 mm, 6.4 mm, and 8.2 mm from the archwire, matching the power arm. Finite element analysis was performed using linear mechanical properties and an explicit method. Results: With the power arm, increasing vertical length led to greater extrusion, while the posterior force remained unchanged. The lever jig also showed increased extrusion with length but to a lesser extent. Posterior force increased proportionally with the lever jig length. Initial displacement analysis showed greater extrusion and distal tipping with the power arm, while the lever jig suppressed extrusion and facilitated controlled tipping. Stress analysis revealed a more uniform periodontal ligament stress distribution with the lever jig. Conclusion: The lever jig minimizes extrusion and enhances force concentration posteriorly, promoting efficient distal movement. Full article

Sex identification is often challenging, especially when only skeletal remains are available. While previous research has primarily focused on skull measurements, dental traits have received less attention. This study aimed to measure the upper and lower canines, molars, and tooth rows of raccoon dogs in Lithuania to examine sexual dimorphism and analyze the correlation between different teeth and tooth row measurements. A total of 90 skulls with lower jaws of adult raccoon dogs were examined, including 55 males and 35 females. Osteometric analysis followed standard protocols, with canine measurements adapted using a method tailored to the dentition of carnivorous species. Of all the study measurements, the canine teeth demonstrated the most significant sex differences. The correlation analysis showed a strong correlation (p < 0.001) between the dimensions of the upper molars P⁴, M¹, and M². The upper tooth rows were strongly correlated (p < 0.001) with the dimensions of the P⁴ and canines. Lower molar correlations were weaker than upper ones, and lower tooth rows showed less correlation with tooth measurements. These findings indicate that molars and tooth rows are not reliable for sex determination in raccoon dogs. However, the observed sexual dimorphism in canine teeth may offer insights for future zooarchaeological and comparative anatomical studies. Full article

Background/Objectives: Intraoral (IO) radiographs are critical for endodontic diagnostics, yet conventional orthoradial imaging often results in superimposition, limiting the visibility of individual root canals. Maxillary first premolars pose challenges due to their anatomical characteristics and positioning within the dental arch. This study aimed to retrospectively analyze cone-beam computed tomography (CBCT) data to determine the horizontal X-ray beam angulations for maxillary first premolars at which root canals overlap and neighboring tooth superimposition occur, providing clinically relevant guidance for optimizing IO radiographic techniques. Methods: CBCT scans from 85 patients were analyzed using ImageJ software to measure the angles at which maxillary first premolar root canals overlap or become obscured by adjacent teeth. The mean angles for canal overlap and neighboring tooth superimposition were determined. Statistical analysis was performed using SPSS Version 29.0, and the level of significance was set to 5%. Results: The mean angle for root canal overlap was 93.56° (±10.08). The angles at which neighboring teeth began to superimpose were 124.38° (±9.91) for the distal contour of the canine and 63.46° (±9.38) for the mesial root contour of the second premolar. No significant differences were observed between apical and coronal measurements for root canal overlap but tapering of the roots led to significant differences in neighboring tooth superimposition (p < 0.05). Conclusions: A mesial beam shift within a calculated safe corridor (98.5–129.5°) optimizes canal separation without superimposition from adjacent teeth. For ideal visualization, a mesial angulation close to 40° is recommended. These findings support improved IO radiographic techniques while minimizing the risk of retakes in adherence to the ALARA principle. Full article

Background: Cemento-ossifying fibroma (COF) is a benign, non-aggressive fibro-osseous tumor in which normal bone is replaced by fibrous tissue containing collagen fibers, bone, or cementum-like material. Although COF is rare in children, its occurrence requires careful management due to its potential impact on tooth development and occlusion. Surgical excision is the widely used treatment; however, post-operative occlusal guidance is crucial, particularly in pediatric patients. Case report: This case report presents the early intervention using a preformed eruption guidance appliance (EGA) following the excision of COF in a 5-year-old boy. The patient exhibited premature loss of the primary canine and displacement of the devel-oping permanent tooth bud. After surgical excision, an EGA was applied to facilitate proper eruption of the successor teeth and optimize oral muscle function. Over a four-year follow-up period, the permanent teeth in the affected area erupted favorably, and intercuspal relationships improved during the transition from primary to mixed dentition. Conclusions: Given the limited research on the long-term effects of COF on developing dentition, long-term follow-up and additional studies are necessary to further evaluate its impact and the effectiveness of eruption guidance appliances in pediatric patients. Full article

The periodontal ligament (PDL) is a fibrous connective tissue that anchors the tooth-root surface to the alveolar bone with specific orientations. It plays a crucial role in functional restoration, optimal position stabilities, biomechanical stress transmission, and appropriate tissue remodeling in response to masticatory loading conditions. This pilot study explored spatial microarchitectures to promote PDL orientations while limiting mineralized tissue formation. A computer-designed perio-complex scaffold was developed with two parts: (1) PDL-guiding architectures with defined surface topography and (2) a bone region with open structures. After SEM analysis of micropatterned topographies on PDL-guiding architectures, perio-complex scaffolds were transplanted into two-wall periodontal defects in the canine mandible. Despite the limited bone formation at the 4-week timepoint, bone parameters in micro-CT quantifications showed statistically significant differences between the no-scaffold and perio-complex scaffold transplantation groups. Histological analyses demonstrated that the PDL-guiding architecture regulated fiber orientations and facilitated the functional restoration of PDL bundles in immunohistochemistry with periostin and decorin (DCN). The perio-complex scaffold exhibited predictable and controlled fibrous tissue alignment with specific angulations, ensuring spatial compartmentalization for PDL tissues and bone regenerations. These findings highlighted that the perio-complex scaffold could serve as an advanced therapeutic approach to contribute periodontal tissue regeneration and functional restoration in tooth-supporting structures. Full article