Search Results (4,423)

Background: Lingual orthodontic systems have recently advanced with the introduction of fully customized CAD/CAM-based designs featuring self-ligating (SL) mechanisms. This study aimed to evaluate the three-dimensional accuracy of a customized SL lingual system in reproducing digitally planned tooth positions. Methods: A total of 280 teeth were analyzed following treatment with a fully customized self-ligating lingual system (Harmony^®, Aso International Inc., Tokyo, Japan). Digital models obtained before treatment (T0), from the setup (TS), and after treatment (T1) were superimposed using a best fit algorithm in GOM Inspect. Tooth movements were quantified across seven biomechanically relevant parameters including tip, torque, rotation, buccolingual, mesiodistal, vertical, and overall displacement. Predicted and achieved movements were compared using paired t tests and Bland–Altman analysis. Results: The fully customized SL lingual appliance achieved an overall dentition accuracy of 92.1%. Mean accuracy for linear tooth movements was 94.5% ± 2.1% in the maxilla and 93.8% ± 2.5% in the mandible. For angular movements, mean accuracy was 90.8% ± 3.4% in the maxilla and 89.3% ± 3.9% in the mandible. The highest precision was observed in anterior teeth for mesiodistal (96.2%) and buccolingual (95.8%) movements, whereas the lowest accuracy occurred in rotational movements of the posterior segments (87.1%). No statistically significant differences were found between predicted and achieved movements for most parameters (p > 0.05). Conclusions: The fully customized SL lingual orthodontic system demonstrated high accuracy in reproducing digitally planned tooth movements, particularly in the anterior segments. Although accuracy was slightly lower in the posterior regions, the overall outcomes remained mechanically and clinically acceptable across all evaluated dimensions. Full article

Background: Mechanical loading is a fundamental regulator of bone remodelling; however, the mechanotransduction mechanisms governing alveolar bone adaptation under tensile-dominant orthodontic loading remain insufficiently defined. In particular, the molecular pathways associated with tension-driven cortical modelling in the periodontal ligament (PDL)–bone complex have not been systematically interpreted in the context of advanced biomechanical simulations. Methods: A nonlinear finite element model of the alveolar bone–PDL–tooth complex was developed using patient-specific CBCT data. Three loading configurations were analysed: (i) conventional orthodontic loading, (ii) loading combined with corticotomy alone, and (iii) a translation-dominant configuration generated by the Bone Protection System (BPS). Pressure distribution, displacement vectors, and stress polarity within the PDL and cortical plate were quantified across different bone density conditions. The mechanical outputs were subsequently interpreted in relation to established mechanotransductive molecular pathways involved in osteogenesis and angiogenesis. Results: Conventional loading generated compression-dominant stress fields within the marginal PDL, frequently exceeding physiological thresholds and producing moment-driven root displacement. Corticotomy alone reduced local stiffness but did not substantially alter stress polarity. The BPS configuration redirected loads toward a tensile-favourable mechanical environment characterised by reduced peak compressive pressures and parallel (translation-dominant) displacement vectors. The predicted tensile stress distribution is compatible with activation profiles of key mechanosensitive pathways, including integrin–FAK signalling, Wnt/β-catenin–mediated osteogenic differentiation and HIF-1α/VEGF-driven angiogenic coupling, suggesting a microenvironment that may be more conducive to cortical apposition than to resorption. Conclusions: This study presents a computational–molecular framework linking finite element–derived tensile stress patterns with osteogenic and angiogenic signalling pathways relevant to alveolar bone remodelling. The findings suggestthat controlled redirection of orthodontic loading toward tensile domains may shift the mechanical environment of the PDL–bone complex toward conditions associated with osteogenic than resorptive responses providing a mechanistic basis for tension-induced cortical modelling. This mechanobiological paradigm advances the understanding of load-guided alveolar bone adaptation at both the tissue and molecular levels. Full article

Background/Objectives: Malocclusion is one of the most prevalent oral health concerns in paediatric dentistry, with anterior open bite (AOB) and posterior crossbite (PCB) being among the most common forms. Non-nutritive sucking habits (NNSHs), including digit-sucking habits (DSHs) and pacifier-sucking habits (PSHs), have been linked to malocclusion development. While both habits are known to impact dental and skeletal development, their comparative effects remain unclear. This systematic review and meta-analysis aims to determine the difference in the development and prevalence of anterior open bite and posterior crossbite between patients with digit-sucking and pacifier-sucking habits. Materials and Methods: An exhaustive review of the literature was conducted on the 25 November 2024 across three databases, namely EBSCOhost (including PubMed-Medline), Web of Science and Scopus. The following PICO question was constructed for the systematic review: “In children and teenagers, is there a difference in the development and prevalence of malocclusions (Anterior Open bite & Posterior Crossbite) between patients with a history of digit sucking habits and patients with a history of pacifier sucking habits?”A meta-analysis was also performed with the selected studies, and the software used to carry out the meta-analysis was R 4.3.1 (R Core Team (2023)). Results: From the initial search, 102 articles were found and a further 11 articles were obtained from manual findings. 12 articles were included in the final systematic review and meta-analysis. The meta-analysis indicated that the risk of AOB and PCB was increased by both DSH and PSH. Conclusions: Both DSH and PSH significantly increased the risk of AOB and PCB. PSH posed a significantly higher risk than DSH for PCB development (OR = 2.66, p < 0.001), while no significant difference in AOB prevalence was observed between DSH and PSH (OR = 1.77, p = 0.150). Full article

Background: Non-syndromic cleft lip/palate (NCL/P) is a prevalent congenital anomaly. Despite an unclear epidemiological link between orofacial clefts and dental caries, genetic studies suggest that polymorphisms in taste receptor genes may influence caries risk. Objectives: This study had two primary objectives: (1) to compare SNPs in NCL/P-associated genes (IRF6, FOXE1) between Kuwaiti NCL/P cases and controls, and (2) to explore whether variants in caries-associated (KLK4, DSPP) and taste receptor (TAS1R2, TAS2R38) genes are associated with dental caries susceptibility in individuals with NCL/P, independent of overall caries prevalence. Methods: A case–control design was employed, with 25 NCL/P cases and 25 unaffected controls recruited from a Dental Craniofacial Clinic in Kuwait. Genomic DNA was extracted from buccal swabs, and SNP genotyping was performed using real-time PCR for genes related to NCL/P, dental caries, and taste perception. Caries status was assessed using the dmft/DMFT scoring system. The genotyped genes included NCL/P-related (IRF6, FOXE1), caries-related (KLK4, DSPP), and taste receptor genes (TAS1R2, TAS2R38). Results: At nominal significance, KLK4, DSPP, and TAS1R2 showed associations with NCL/P status, while IRF6 and FOXE1 did not. After applying Benjamini–Hochberg FDR correction across 10 SNPs, no allele- or genotype-level association remained significant (q < 0.05). The strongest signal was KLK4 rs2235091 (allele-level p = 0.016; q = 0.159). An exploratory age- and sex-adjusted logistic model for KLK4 suggested a possible effect (aOR 0.40; 95% CI 0.18–0.87; p = 0.021). Within-group analyses of caries burden revealed no associations that survived FDR control (lowest q = 0.056 for FOXE1 in controls). Conclusions: After controlling for multiple testing, no SNP showed a statistically significant association with NCL/P or caries burden. Nominal signals for KLK4, DSPP, and TAS1R2 did not survive FDR correction; an exploratory adjusted model suggested a possible KLK4 effect, but this requires cautious interpretation. The small sample size is a key limitation, and the findings highlight the need for larger, well-powered studies to clarify genetic contributions to NCL/P and caries risk. Full article

Management of maxillomandibular transverse discrepancy (MTD) is essential for achieving stable, functional, and esthetic occlusion. This study aimed to evaluate the maxillomandibular transverse dimensions and discrepancies in relation to vertical skeletal patterns using digital dental casts and cone-beam computed tomography (CBCT) images. A total of 180 untreated adult subjects were classified into three vertical groups based on the SN-MP angle: hypodivergent (<27°), normovergent (27–37°), and hyperdivergent (>37°), with 60 subjects in each group. Dental arch widths using casts (DAWs-Casts) were measured at the canine, first premolar, first molar, and second molar, while basal arch widths using casts (BAWs-Casts) were measured at the mucogingival junction apical to the corresponding cusp tips. CBCT images were used to measure basal arch widths (BAWs-CBCT) at the estimated centers of resistance (CRes). DAW-Cast, BAW-Cast, and BAW-CBCT measurements were affected by vertical skeletal patterns. Therefore, maxillomandibular dimensions and discrepancies vary according to vertical skeletal pattern, underscoring the need for careful evaluation when planning treatment protocols for patients with MTD. Full article

Background/Objectives: Geometric morphometric analysis (GMA) is a statistical method that captures and quantifies shape variation. This study aimed to assess hard and soft tissue shape variations and changes following orthodontic treatment in Class III skeletal malocclusion using GMA. Methods: A retrospective study was conducted on 84 lateral cephalometric radiographs (pre-treatment and near-end treatment) of Class III patients aged 16–40 years (ANB < 2°). Thirty-five landmarks were digitized in Cartesian coordinates using MorphoJ software for shape analysis. Results: The sample included 62% females and 38% males, with a mean age of 24.7 ± 5.2 years. Vertical dimension variations (hypodivergent to hyperdivergent) contributed most to shape changes PC1 (23.35%), followed by anteroposterior variations PC2 (13.51%). Gender significantly influenced hard and soft tissue variation with 30.91%SS (F = 56.99, p < 0.0001). Males had significantly larger and longer ramus, body of the mandible, alveolar height, LAFH, TAFH and upper lip length. (PD: 0.026, p < 0.05). Significant shape changes were seen in the mandible (PD = 0.018, p < 0.05). SNB increased by 0.41° (from 81.73° ± 3.67°), and ANB improved by 0.46° but remained Class III (−0.33° ± 1.82°). Lower anterior facial height increased by 1.78 mm (p < 0.05). The lower incisors retroclined significantly (from 92° ± 8.56° to 87° ± 6.96°, p < 0.05), while the interincisal angle increased by 5.9°. Upper incisors remained procline (118° ± 11°, p > 0.05). Upper lip length increased by 0.4 mm (p < 0.05). Conclusions: Vertical and anteroposterior shape variations are notable within Class III malocclusion. Post-treatment changes in both hard and soft tissues indicate that orthodontic camouflage can enhance facial esthetics and skeletal balance. GMA provides objective quantification and visualization of these treatment-related craniofacial changes. Full article

Background/Objectives: The rotation of maxillary canines represents one of the least predictable movements with clear aligners, particularly in cases requiring rotations greater than 10°, due to the rounded crown morphology and limited aligner grip. The aim of this retrospective study was to compare three different crescent-shaped attachment designs (vertical, horizontal, and oblique) for maxillary canine rotations greater than 10° with clear aligners. Methods: Seventy-eight maxillary canines were retrospectively selected and allocated into three equal groups (n = 26) according to the orientation of the applied attachment: vertical, horizontal, or oblique crescent-shaped attachments. Digital STL models (initial, predicted, and final) were imported into Dolphin 3D software 12.0.63 to assess the accuracy of maxillary canine’s rotation through the comparison between planned and achieved values. Results: Mean rotational accuracy was 55.10% ± 15.60 for the vertical group, 62.40% ± 16.10 for the horizontal group, and 64.60% ± 19.40 for the oblique group. One-way ANOVA showed no statistically significant differences among groups (p = 0.09). Pairwise analysis revealed a statistically significant difference between the oblique and vertical designs (p = 0.05). Conclusions: Attachment orientation may influence the accuracy of maxillary canine rotation with clear aligners, with oblique crescent-shaped attachments showing a trend toward improved rotational control. Full article

Background: Patients with dental phobia frequently require intravenous sedation (IVS) to undergo dental treatment; however, some can gradually discontinue IVS through repeated clinical experiences. The physiological and psychological factors influencing successful IVS withdrawal remain unclear. This study aimed to compare physiological (sAA, HR) and subjective (VAS) measures between patients who discontinued IVS and those who remained dependent on IVS. Methods: This prospective cohort study included 51 patients with dental phobia treated under IVS. Participants were classified into a Non-Sedation Group (NSG; n = 25) and a Sedation-Dependent Group (SDG; n = 26) based on their ability to discontinue IVS during the course of treatment. Salivary alpha-amylase (sAA), heart rate (HR), and visual analog scale (VAS) scores for fear, tension, and anxiety were assessed at predefined time points from the waiting room to venous cannulation. Treatment satisfaction and expectations for future treatment were also evaluated. Results: sAA activity was significantly higher in the SDG than in the NSG at T0 and T1 (p < 0.05), indicating higher levels of selected physiological measures during anticipatory phases; however, the difference at T2 was not significant. HR differed significantly only in the waiting room, whereas no between-group differences were observed in self-reported VAS scores for fear, tension, or anxiety at any time point, indicating a dissociation between physiological and subjective stress measures. Treatment satisfaction and expectations for future treatment were significantly higher in the SDG. Conclusions: Patients who remained dependent on IVS showed higher levels in selected physiological measures at the group level during anticipatory stages, whereas no corresponding differences were observed in self-reported subjective measures. These findings are exploratory and descriptive in nature and do not imply predictive or causal relationships. Full article

The spatial relationship between the incisive canal (IC) and maxillary central incisors (U1) is a critical anatomical consideration during orthodontic tooth movement, particularly in patients with maxillary dental midline deviation. This study aimed to evaluate the proximity between the IC and U1 roots in relation to maxillary dental midline deviation using cone-beam computed tomography (CBCT) images. Sixty-four patients with skeletal Class I malocclusion were divided into two groups according to the degree of the maxillary dental midline deviation. Group 1 (n = 32; mean age, 23.95 ± 5.40 years) exhibited < 2 mm deviation (0.28 ± 0.39 mm), whereas Group 2 (n = 32; mean age, 27.75 ± 6.21 years) showed > 2 mm deviation (2.45 ± 0.57 mm). CBCT images were analyzed to measure U1 root length and inclination, IC width, inter-root distance, and U1-IC proximity. In Group 2, the anteroposterior U1-IC distance on the deviated side was significantly shorter than on the contralateral side (p < 0.05), while the shortest U1–IC distances did not differ significantly between sides (p > 0.05). Moreover, a significant negative correlation was observed between differences in U1 inclination and root proximity at most vertical levels, indicating that a more proclined U1 on the deviated side tended to be closer to the IC. These findings suggest that maxillary dental midline deviation may be associated with asymmetric positioning of the U1 relative to the IC and underscore the importance of careful three-dimensional evaluation and individualized biomechanical control when planning orthodontic treatment in patients with midline asymmetry. Full article

Background: Artificial intelligence (AI) integrated with cone-beam computed tomography (CBCT) has rapidly advanced the diagnostic capability of orthodontics, particularly for quantifying external root resorption (ERR). High-risk scenarios such as bilateral maxillary canine impaction require objective tools to guide treatment decisions and prevent irreversible damage. Objectives: To evaluate the diagnostic accuracy and clinical applicability of AI-assisted CBCT for orthodontically induced ERR, and to demonstrate its value in a complex clinical case where decision-making regarding canine traction versus extraction required precise risk quantification and definition of biological limits. Methods: A systematic review following PRISMA 2020 guidelines was conducted in PubMed, ScienceDirect, and Cochrane Library (2015–September 2025). Eligible studies applied AI-enhanced CBCT to assess ERR in orthodontic patients. Additionally, a clinical case with bilaterally impacted maxillary canines was evaluated using CBCT with automated AI segmentation and manual refinement to quantify root volume changes and determine prognostic thresholds for treatment modification. Results: Nine studies met the inclusion criteria. AI-based imaging, predominantly convolutional neural networks, showed high diagnostic accuracy (up to 94%), improving reproducibility and reducing operator dependency. In the clinical case, volumetric monitoring showed rapid progression of ERR in the lateral incisors (LI) associated with a persistent unfavorable 3D spatial relationship between the canines and incisor roots, despite controlled distal traction with skeletal anchorage, leading to a timely change in the treatment plan and extraction of the severely compromised incisors with substitution by the canines. AI-generated data provided objective evidence supporting safer decision-making and prevented further structural deterioration. Conclusions: AI-enhanced CBCT enables early, objective, and quantifiable ERR assessment, strengthening prognosis-based decisions in orthodontics. Findings of this review and the clinical case highlight the translational relevance of AI for managing high-risk cases, such as maxillary canine impaction with extensive LI resorption, supporting future predictive AI models for safer canine traction. Full article

In fixed orthodontic treatment, brackets are orthodontic attachments bonded to the tooth enamel, and their placement and removal may affect the underlying enamel surface. Enamel degradation is a critical factor for oral health, as it reduces the mechanical strength of teeth and increases susceptibility to caries and erosion. Accurate diagnosis of enamel changes is therefore essential for the evaluation of preventive and restorative treatments. In this study, enamel degradation was investigated via two integrated methods: energy-dispersive X-ray spectroscopy (EDS) and surface roughness measurement. The experimental protocol was performed in three stages: before bracket bonding, after bracket removal, and after applying a remineralization treatment. The experimental design included a repeated-measures structure, with stage (baseline, post-debonding, post-remineralization) as the within-tooth factor and bracket type (sapphire vs. metallic) as the between-tooth factor. Given the violation of the variance homogeneity assumption, group comparisons were ultimately performed using Welch ANOVA followed by Games–Howell post hoc tests, with Bonferroni-adjusted values used for pairwise comparisons. The presence of orthodontic brackets can influence enamel mineralization because the bonding and debonding procedures modify the enamel surface microtopography. These procedures can generate microcracks and surface irregularities, which may affect mineral exchange between enamel and the surrounding environment. In our study, bracket removal led to a significant decrease in the mean atomic percentages of Ca (from 32.65% to 16.37% for sapphire) and P (from 16.35% to 8.60% for sapphire), accompanied by a sharp increase in surface roughness. After remineralization, Ca and P levels increased, while roughness decreased. However, neither the mineral content nor the surface topography fully returned to the initial values, indicating that remineralization achieved only a partial recovery of enamel integrity. These findings highlight that the integrated EDS approach and roughness analysis offer a promising descriptive framework for assessing enamel degradation and monitoring the effectiveness of remineralization therapies. The generated mathematical model provides a powerful descriptive framework for the in vitro data obtained, correlating roughness with mineral composition and treatment stage. However, such a high goodness-of-fit (R² > 0.98) should be interpreted cautiously due to the risk of overfitting. Therefore, rigorous external validation is mandatory before this model can be considered a reliable predictive tool. It also highlights the importance of enamel remineralization therapies after orthodontic treatment, but also the importance of choosing personalized treatment strategies adapted to the enamel type. Full article

Background/Objectives: Surfactin is a biosurfactant with various biological activities, including antibacterial and anti-inflammatory properties; however, its effects on bone metabolism remain poorly understood. This study aimed to investigate the effects of surfactin on osteoclast differentiation and elucidate its underlying molecular mechanisms. Methods: RAW264.7 cells were treated with receptor activator of nuclear factor-kappa B ligand (RANKL) and surfactin, and osteoclast differentiation and maturation were evaluated by tartrate-resistant acid phosphatase and F-actin staining, respectively. Gene expression of differentiation markers was assessed using real-time reverse transcription-quantitative polymerase chain reaction, while the kinetics of intracellular signaling molecules and transcription factors were analyzed using Western blot analysis. Results: Surfactin treatment significantly inhibited osteoclast differentiation and maturation, as well as the mRNA expression of Nfatc1, Acp5, and Cathepsin K. Although surfactin did not markedly affect RANKL-induced activation of the NF-κB or MAPK-mediated signaling, it significantly suppressed the expression of c-Fos at both the mRNA and protein levels. Furthermore, surfactin attenuated the phosphorylation of Elk1, a transcription factor involved in c-Fos induction. Conclusions: Surfactin inhibits RANKL-induced osteoclast differentiation by negatively regulating the Elk1-AP-1-NFATc1 axis. Surfactin may thus be a promising therapeutic candidate for the treatment of metabolic bone disorders and inflammatory bone destruction. Full article

Functional appliances constitute a common treatment approach for skeletal Class II malocclusion. However, evidence regarding the effects of appliance design and manufacturing workflows on treatment outcomes remains limited. This study aimed to compare the skeletal, dentoalveolar, and soft tissue effects of conventionally fabricated, prefabricated, and digitally designed functional appliances. A total of 28 growing patients with skeletal Class II malocclusion were retrospectively assessed and evenly assigned to four treatment groups: Twin Block, PowerScope, Invisalign Mandibular Advancement, and digitally designed Herbst. Skeletal, dentoalveolar, and soft tissue parameters were evaluated using lateral cephalometric radiographs obtained before (T0) and after treatment (T1). Statistical analyses included one-way ANOVA, repeated-measures ANOVA, and the Kruskal–Wallis test. All treatment modalities demonstrated significant sagittal improvement, characterized by reductions in ANB and Wits values and increases in SNB angle and mandibular length (Co–Gn). The Twin Block appliance showed a significantly greater increase in mandibular length compared with the other groups (p = 0.037). Dentoalveolar adaptations were more pronounced in the PowerScope and Invisalign Mandibular Advancement groups. In conclusion, within the limitations of this retrospective pilot study, functional appliances with different design and manufacturing characteristics appear to produce distinct skeletal and dentoalveolar response patterns, and digitally designed systems may represent clinically effective alternatives for the treatment of skeletal Class II malocclusion; however, these findings should be considered preliminary and interpreted with caution. Full article

Gingival recession, particularly in patients exhibiting a thin periodontal phenotype, is a prevalent and challenging complication associated with orthodontic treatment, among other factors. Recent advances in biostimulation therapies aim to support soft tissue augmentation by increasing gingival thickness (GT) and keratinized tissue width (KTW) while minimizing the need for invasive surgical procedures. This narrative review explores the available clinical evidence regarding several biostimulation techniques, including injectable platelet-rich fibrin (i-PRF), microneedling (MN), concentrated growth factors (CGF), atelocollagen, hyaluronic acid (HA), and low-level laser therapy (LLLT), with a particular focus on their potential adjunctive role in orthodontic patients with a thin periodontal phenotype. While i-PRF and microneedling—used alone or in combination—have shown promising short-term soft tissue thickening and reduced patient morbidity when compared with conventional grafting procedures, the available evidence is largely derived from small, randomized trials, pilot studies, and non-orthodontic cohorts, limiting the strength of comparative conclusions. Minimally invasive biostimulation techniques may represent potential adjunctive strategies for soft tissue management in selected clinical scenarios. Nevertheless, current evidence remains limited and heterogeneous, and robust, long-term, orthodontic-specific clinical trials are required before these approaches can be considered reliable alternatives to established surgical protocols or validated preventive strategies against gingival recession. Full article