Gaining representative biopsy samples in suspicious mandibular bone structures represents a challenging procedure as a result of the complex associated anatomy. Although 3D-printed drilling templates have been reported to improve biopsy accuracy significantly compared to freehand procedures, only limited data is available on the precision of dynamically navigated biopsies. The aim of this experimental study was to compare the accuracy of dynamically navigated biopsies with freehand biopsy procedures. Computed tomography data of virtual mandibular (suspicious) bone lesions was segmented and reconstructed into complete 3D-models. Subsequently, two identical mandibular models – one for the navigation group and one for the freehand group - including the intracortical lesion were produced using 3D-printing. This was followed by Cone Beam Computed Tomography (CBCT) of each model for resegmentation and planning of a standardized biopsy channel. For simulating realistic clinical conditions, the models were fixed in a phantom head and on an operating table. In the navigation group the biopsies were performed using a dynamic navigation system (X-Guide) and in the control group the biopsies were performed by freehand procedure. Following the experimental surgical procedures the models were scanned again (CBCT) and the accuracy was assessed by calculating the deviation of the actual biopsy axis from the planned axis. Eight comparable biopsies were performed by using the dynamic navigation system and the freehand procedures in each group. The mean deviation between the planned axis and the actual biopsy path was significantly lower in the navigation group (1.51 mm ± 0.5 mm) than in the freehand group (4.11 mm ± 1.9 mm). Dynamically navigated biopsies of the mandible show a significantly higher accuracy than freehand procedures and represent a promising novel method for improving diagnostic certainty for biopsies of suspicious structure in the mandible.
The present study aimed to evaluate the efficacy of adjunctive topical 5-fluorouracil in reducing recurrence following conservative surgical management of ameloblastomas (enucleation, curettage, with or without peripheral ostectomy). A secondary objective was to assess the incidence of long-term inferior alveolar nerve injury. This retrospective matched cohort study enrolled 23 patients who were treated conservatively for histopathologically confirmed ameloblastoma with adjunctive topical 5-fluorouracil between January 2015 and June 2023, of whom 17 were included in the final analysis. Surgical procedures consisted of enucleation and/or curettage, with 5
This retrospective study evaluates a novel approach for the correction of high-level maxillary hypoplasia. Deficiency of the midface at the nasolabial area (low-level deficiency) can be effectively corrected using conventional Le Fort I osteotomy. However, midface deficiency at the level of the zygoma, infraorbital region, and lateral nasal region (high-level deficiency) cannot be adequately addressed through standard Le Fort I advancement alone. Management options for high-level deficiency include high-level Le Fort I osteotomy, alloplastic implants, or injectable fillers. In this study, 35 patients requiring orthognathic surgery (either bimaxillary surgery or isolated maxillary osteotomy) underwent simultaneous placement of alloplastic implants, including silicone and polyetheretherketone (PEEK) implants. A minimally invasive technique was used to perform the Le Fort I osteotomy. Through the same intraoral incision, the incision was extended, and a subperiosteal pocket was dissected in the zygomatic region to allow proper placement of the implant, following principles described in previously published techniques (e.g., Niamtu et al.). The size and shape of the implant were determined based on preoperative clinical evaluation and confirmed intraoperatively. Each implant was secured in the desired position using two titanium screws. Postoperative follow-up revealed satisfactory outcomes in the majority of cases. Only one case of infection was reported, which occurred in a silicone implant. All patients demonstrated noticeable improvement in lateral and oblique facial profiles and expressed satisfaction with the aesthetic outcomes during follow-up visits. The findings of this study demonstrate the feasibility of performing Le Fort I osteotomy in conjunction with simultaneous alloplastic implant placement during a single operative session. This combined approach reduces the psychological burden associated with undergoing two separate procedures and provides a more cost-effective treatment option while achieving enhanced midfacial contour and aesthetic improvement.
Abstract Background Studies on animal models and fibroblast growth factor receptor (FGFR2)-associated craniosynostosis syndromes suggest that FGFR2 plays a crucial role in craniofacial development. Therefore, the present exploratory study aims to investigate the relationship between functional genetic polymorphisms of FGFR2 and variations in facial morphology. Methods Frontal and lateral photographs of healthy boys (aged 9 to 14 years) and girls (aged 9 to 13 years), taken before the start of orthodontic treatment, were used for the study. Saliva samples from the patients were also analyzed. Patients with syndromes, skull trauma, or cleft lip and palate were excluded from the study. The measurements and determinations of proportions were performed using the Image J image processing program. DNA was extracted from the saliva samples to investigate seven genetic polymorphisms in FGFR2 using real-time PCR (rs2162540, rs2981578, rs10736303, rs1078806, rs11200014, rs1219648, and rs4752566). ANOVA and t-tests were used to investigate the relationship between the genotypes and the horizontal as well as lateral facial proportions. Results A total of 102 children (60 boys and 42 girls) were included in the analysis. No significant sex-related differences in relative facial dimensions or angles were observed. FGFR2 polymorphisms were significantly associated with distinct facial parameters. The rs10736303 variant was associated with frontal facial proportions related to the eye and midface region, with larger relative dimensions observed in carriers of the AA genotype compared to the AG genotype. The rs2162540 polymorphism was associated with lateral profile measurements, including the relative vermilion height of the lower lip and the mentolabial angle. In addition, rs11200014 showed a significant association with the mentolabial angle, with larger angles observed in AA genotype carriers. Conclusion This exploratory study suggested that FGFR2 polymorphisms may be involved in specific facial parameters, supporting a role of FGFR2 in facial development.
To assess whether routinely measured systemic inflammatory and metabolic biomarkers are related to the initial severity of hearing impairment in patients presenting with sudden sensorineural hearing loss (SSNHL). This retrospective case-control study included 613 adult inpatients with SSNHL treated between January 2020 and December 2024 and 850 healthy individuals undergoing routine health examination during the same period. Hearing loss severity was classified into mild, moderate, severe, and profound categories according to the baseline pure-tone average (PTA)-based audiological assessment. Continuous variables were summarized as median (interquartile range) and compared using non-parametric tests. Associations with PTA-defined severity were evaluated using ordinal logistic regression, with sequential adjustment for demographic and metabolic covariates. Collinearity, model fit, proportional odds assumption, missingness, and sensitivity analyses were assessed. Compared with controls, patients with SSNHL had higher total cholesterol, LDL-C, glucose, neutrophil count, NLR, platelet count, PLR, MPV, and ApoA1, and lower lymphocyte count and triglycerides. Among patients with SSNHL, the severity distribution was mild in 320 patients (52.2
Abstract Background This study aimed to evaluate the association between single nucleotide polymorphisms (SNPs) in endochondral development-related genes and cranial base 3D phenotypes. Methods CBCT scans and the genomic DNA of 118 individuals were evaluated (age range: 15–66 years; 82 females). Data from eleven 3D landmarks identified at the cranial base were subjected to geometric morphometric analysis, including Procrustes fit, principal component (PC) analyses, and estimation of centroid sizes and fluctuating asymmetry scores. Seven SNPs within BMP2 , BMP4 , RUNX2 , and SMAD6 were genotyped by real-time PCR. General linear models (GLM) were fitted to assess the effect of SNPs on cranial base shape, size, and symmetry quantitative traits. Results Seven PCs were identified for each shape variation aspect (i.e., symmetric and asymmetric components). These explained 81.9% and 84.6% of the total variation, respectively. GLM did not evidence strong associations between cranial base shape aspects and the studied SNPs. GLM including age, sex and BMP2 rs1005464 as predictor variables, showed a strong explanatory power of the variation in the size of the cranial base (adjusted R 2 = 0.50). Individuals carrying at least one A allele for rs1005464 had larger cranial bases than common GG homozygotes (β = 0.015; 95% CI: 0.003, 0.027; P = 0.016). Fluctuating asymmetry scores were not associated with any of the evaluated SNPs. Conclusions The results suggest that BMP2 rs1005464 could be associated with variations in the cranial base size.
To evaluate the association of symptoms of myofascial pain and dysfunction with the presence of tinnitus in adults. A case-control study involving 80 cases presenting tinnitus and 160 controls without this condition was designed. Sociodemographic variables as well as symptoms of myofascial pain and dysfunction measured using the Brux-Screen, psychopathological symptoms obtained from the Symptom Checklist Revised (SCL-90-R) and Perceived Stress Scale (PSS-10), stressful life events score quantified through the Social Readjustment Rating Scale (SRRS) and presence of tinnitus supported by items of the Tinnitus Handicap Inventory (THI) were collected. A directed acyclic graphs (DAG) analysis was performed to identify potential relationships, and multivariable logistic regression used to assess associations. Exposure to high levels of noise (OR = 2.29; 95
Abstract Background This cross-sectional study aimed to evaluate occlusal characteristics and masticatory performance in patients with skeletal Class II and Class III malocclusions. Both digital occlusal analysis and standardized bolus analysis were employed to assess functional outcomes in non-surgically treated, surgically treated, and control patients. Methods A total of 133 orthognathic patients (71 female; median age 29.8 years) and 20 controls (9 female; median age 30.0 years) were included. Skeletal malocclusions were categorized as compensated, decompensated, and a separate surgically treated cohort assessed at 5-year postoperative follow-up. Digital occlusal parameters (total tooth contact (TTC), time of occlusion (TOC), occlusal asymmetry (OAS), anterior and posterior tooth contact (ATC, PTC)) were recorded and masticatory performance was assessed using a standardized two-color bolus analysis. Results Non-surgically treated Class II and Class III patients showed significantly reduced TTC, ATC, PTC, and prolonged TOC as well as lower bolus mixing scores compared with controls (p < 0.05). Surgically treated patients at 5-year follow-up exhibited occlusal parameters and bolus mixing scores comparable to controls, indicating normalization of occlusal parameters and masticatory efficiency. Conclusion Skeletal Class II and Class III malocclusions are associated with impaired occlusal function and reduced masticatory efficiency. Orthognathic therapy effectively restores occlusal parameters as well as functional chewing ability in the long term. Combining digital occlusal analysis with bolus analysis provides a comprehensive and objective evaluation of masticatory rehabilitation in orthognathic patients. Trial registration DRKS00025729
The cerebellum contributes to sensory, cognitive, emotional, and pain-modulatory processes beyond motor coordination. In temporomandibular disorders (TMD), alterations in spontaneous cerebellar neural activity and strengthened functional connectivity with limbic structures have been reported, suggesting involvement of central neuroplastic mechanisms. Mandibular displacement and occlusal imbalance may further modulate brain networks related to motor regulation, sensory integration, and pain-related emotional processing. In this study, magnetic resonance imaging(MRI) and diffusion tensor imaging(DTI) was used to examine cerebellar connectivity across different mandibular positions in a patient with painful TMD. Functional MRI and diffusion tensor imaging were acquired in three conditions: centric occlusion, centric relation, and stabilization splint. Cerebellar regions of interest were defined using SUIT parcellation, and position-dependent structural-functional connectivity was assessed using diffusion-based tractography and Δ-metrics computed as the difference between the two tractography-derived matrices (Δ = MNI_NORM − COUNT_NORM); scale-invariant similarity metrics were used for between-condition comparisons. Under centric occlusion (CO), the Δ-derived connectivity pattern was sparse and included ROIs with zero-variance profiles, yielding mathematically undefined correlation entries; these were treated as missing values. In contrast, centric relation and stabilization splint conditions demonstrated heterogeneous Δ patterns and structured ROI-wise correlation profiles. In contrast, both centric relation and stabilization splint conditions showed moderate effect sizes in summary metrics. Pairwise comparison of vectorized Δ matrices (upper triangle; N = 378 ROI pairs) demonstrated a moderate association between CR and splint (Pearson r = 0.452, 95
Segmental Le Fort I osteotomy has traditionally been regarded as less predictable and stable, a perception largely based on two-dimensional evaluation methods. Despite existing systematic reviews on clinical outcomes, a dedicated synthesis of three-dimensional assessments of surgical accuracy and postoperative stability is lacking. This systematic review evaluated three-dimensional (3D) assessment methods and outcome of planning accuracy and postoperative stability in segmented Le Fort I osteotomies. The aim was to determine the reliability of 3D methods in capturing surgical accuracy and long-term skeletal stability. Medline, Embase, Web of Science, and Cochrane were searched up to October 25, 2024. Eligible studies included randomized controlled trials, prospective or retrospective studies, or case series with > 5 patients reporting 3D evaluation of planning accuracy or stability. Exclusion criteria were systematic reviews, meta-analyses, single case reports, ex-vivo or animal studies, and studies involving syndromic patients, facial trauma, or prior maxillofacial surgery. Risk of bias and quality of evidence were assessed using the GRADE approach. Twenty-two studies met inclusion criteria: three randomized and nineteen non-randomized controlled trials. Fourteen assessed planning accuracy, five evaluated stability, and three examined both. Twenty-two studies met the inclusion criteria and were included in the qualitative synthesis. Considerable methodological heterogeneity limited direct comparison and precluded meta-analysis. Overall, segmented Le Fort I osteotomy demonstrated clinically acceptable accuracy; however, certain movements—particularly transverse widening, advancement, and pitch—were more prone to underachievement, with discrepancies ranging from 0.77 to 1.41 mm, 0.55 to 2.69 mm, and 0.12° to 5.22°, respectively. During follow-up, transverse relapse was more pronounced at the dental level (0.39–1.41 mm) compared to skeletal changes (0.05–0.86 mm). Segmented Le Fort I osteotomy shows reliable outcomes in 3D evaluations, but some maxillary movements remain difficult to achieve and maintain such as advancement and pitch. Standardized, voxel-based 3D assessment protocols are recommended to improve comparability and strengthen the evidence base. (PROSPERO registration: CRD42018111854).
To evaluate the effect of build orientation on the fracture load and surface roughness of three-unit provisional fixed partial dentures (FPDs) fabricated by digital light processing (DLP). In this in vitro study, standardized three-unit FPDs were designed and fabricated using a DLP 3D printer at three buccolingual angulations (150°, 180°, and 210°) and three mesiodistal angulations (0°, 15°, and 45°) (n = 12 per group). Surface roughness (Ra, µm) was measured using a profilometer, and fracture load (N) was determined using a universal testing machine. Surface roughness data were analyzed using three-way repeated-measures ANOVA, while fracture load data were analyzed using two-way ANOVA, followed by Tukey post hoc tests (α = 0.05). Buccolingual and mesiodistal angulations significantly affected surface roughness (p < 0.001) and fracture load (p < 0.001). The lowest surface roughness was observed at 210° buccolingual and 45° mesiodistal angulation, whereas the highest fracture load was recorded at 210° buccolingual and 0° mesiodistal angulation. The effect of location on surface roughness was not significant (p = 0.309). Build orientation significantly influences the surface and mechanical performance of 3D-printed provisional FPDs. The 210-degree buccolingual angulation showed favorable outcomes under specific mesiodistal conditions; however, the optimal mesiodistal angulation depended on the desired outcome, with 45 degrees improving surface smoothness and 0 degrees enhancing fracture resistance.
To evaluate the antibacterial activity of leaf extracts derived from Spathodea campanulata as an endodontic irrigant in both in vitro and ex vivo models against Enterococcus faecalis. Aqueous (AQESC), methanolic (MESC), ethanolic (EESC), acetonic (AESC), chloroformic (CESC), and hexanic (HESC) extracts derived from Spathodea campanulata were prepared. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined. A well diffusion assay was employed to compare these extracts against Enterococcus faecalis ATCC 29,212. Human single-rooted teeth were collected, standardized, and inoculated to facilitate the development of a four-week biofilm. These teeth were subsequently divided into three experimental groups, each receiving positive pressure irrigation with 1 mL of one of the following solutions: phosphate-buffered saline (PBS), 2.5
Dentin–cement interface can be considered a critical point in fiber post cementation. Post-space preparation may leave a smear layer and sodium hypochlorite remnants on root dentin, which can compromise bonding between fiber posts and self-adhesive resin cement. This study evaluated the effect of different post-space dentin pretreatment modalities on dentin surface characteristics and push-out bond strength of fiber posts. Forty-five extracted single-rooted mandibular second premolars were endodontically treated and assigned to five groups according to post-space dentin pretreatment (n = 9): 2.5
Botulinum toxin type A (BoNT-A) has been increasingly investigated as a therapeutic option for myogenous temporomandibular disorders (TMD), yet uncertainties remain regarding the duration of its clinical effects and the relevance of dosing parameters. Objective: To systematically evaluate the clinical effects, duration of action, and dosage parameters of BoNT-A in the management of myogenous temporomandibular disorders. Methods: This systematic review followed PRISMA 2020 guidelines and was registered in PROSPERO. Electronic searches were conducted in PubMed/MEDLINE, Embase, Scopus, Web of Science, and LILACS. Randomized clinical trials evaluating BoNT-A for myogenous TMD were included. Study selection, data extraction, and risk of bias assessment using the Cochrane Risk of Bias 2 (RoB-2) tool were performed independently. Due to methodological heterogeneity, a qualitative synthesis was conducted. Results: Ten randomized clinical trials were included. Pain was assessed using validated instruments, including the Visual Analog Scale, Characteristic Pain Intensity, and Numeric Rating Scale. Pain reduction over time was reported in both BoNT-A and control groups, including placebo and conservative therapies. In placebo-controlled trials, BoNT-A did not consistently demonstrate superiority over saline injections. Greater pain reductions were reported in studies involving refractory myofascial pain. Improvements in mandibular function were observed in both intervention and control groups. Clinical effects were generally reported to persist for 8 to 24 weeks. Current evidence is insufficient to determine whether a clinically relevant dose–response relationship exists across the evaluated regimens. Adverse events were mostly mild to moderate and transient. Conclusions: Current evidence does not support the routine use of BoNT-A as a first-line treatment for myogenous temporomandibular disorders. Its use may be considered in selected refractory cases after failure of conservative therapies.
This study aimed to evaluate the in vitro effects of commercially available teething gels with different formulations on epithelial barrier integrity and cellular viability. Six commercially available teething gels were tested at concentrations of 0.1
Background Recurrent aphthous stomatitis (RAS) is one of the most common inflammatory ulcerative disorders that impact the oral mucosa. The etiology of aphthous ulcers is complex and multifaceted; however, emotional stress is considered one of the primary risk factors contributing to their development in younger populations. Objectives This study aimed to determine the prevalence of RAS among a sample of dental students, its correlation with their stress levels, and to identify possible risk factors linked to these oral ulcers. Methods This cross-sectional study involved 4th level dental students at King Salman International University using a standardized questionnaire evaluating medical and dental histories, personal habits, as well as oral hygiene practices including tooth brushing frequency and clinically relevant data regarding oral diseases, particularly RAS, alongside the 10- item Perceived Stress Scale. Results One hundred twenty-eight out of 150 students participated, 68.8% experienced RAS with females exhibiting a significantly lower likelihood of developing aphthous ulcers compared to males (OR = 0.233, p = 0.015). Daily toothbrushing was unexpectedly associated with a markedly increased risk (OR = 9.634, p < 0.001), suggesting a potential underlying mechanism warranting further investigation. Additionally, a family history of recurrent ulcers emerged as the strongest predictor (OR = 34.394, p < 0.001), highlighting a possible genetic predisposition. While poor oral hygiene demonstrated a high odds ratio (OR = 11.224), the association was not statistically significant (p = 0.059), possibly due to wide variability in the data. Similarly, high and moderate stress levels exhibited elevated odds ratios (OR = 8.716 and OR = 6.519, respectively), but their associations did not show statistical significance (p = 0.056 and p = 0.061). Conclusions This research underscored a notable prevalence of RAS among dental students. It also identified familial history of aphthous stomatitis, presence of other dental issues, and regular daily toothbrushing as the three primary risk factors for aphthous lesions. Stress levels did not show a significant association with RAS lesions among dental students. Given that RAS is a multifactorial condition, further investigation into additional intervening factors is warranted.
To compare clinical, aesthetic, and patient-reported outcomes of tunnel technique (TUN) versus envelope flap technique (ENV), both combined with connective tissue graft (CTG), for the treatment of multiple mandibular anterior gingival recession defects in patients with thin gingival phenotype. Fifty-nine patients contributing 103 recession sites in teeth 33–43 were enrolled. Randomisation was performed at the patient level, and all eligible sites within the same patient received the same intervention. Thirty-four patients (59 sites) received TUN + CTG and 25 patients (44 sites) received ENV + CTG. Clinical outcomes were analysed at the site level with patient-level clustering accounted for using mixed-effects models. Root coverage percentage (RC
This study aimed to evaluate a modified posteriorly based approach of superficial temporal neurovascular bundle for temporomandibular joint (TMJ) disc repositioning and suturing in patients with anterior disc displacement without reduction (ADDWoR), and to assess its immediate clinical outcomes. A retrospective analysis was conducted on 132 patients (218 joints) treated at the Affiliated Stomatology Hospital of Guangzhou Medical University between August 2023 and April 2024. All patients were diagnosed with ADDWoR corresponding to Wilkes–Bronstein stages III–V. Open TMJ disc repositioning and suturing were performed using either a posteriorly based or anteriorly based approach relative to the neurovascular bundle. Intraoperative parameters and immediate postoperative outcomes were compared between the two groups. Postoperative MRI confirmed successful disc reduction in 211 of 218 joints. Intraoperative bleeding was significantly higher in the posterior group (25.06 ± 8.00 mL) than in the anterior group (14.52 ± 4.83 mL). Operating duration was also longer in the posterior group (103.1 ±27.64 minvs.87.85 ± 23.93 min). No skin flap perforation occurred in the posterior group, whereas 5 cases were observed in the anterior group. The posterior group exhibited a higher postoperative infection rate (9.09
Accurately estimating biological sex is a fundamental step in forensic odontology, anthropology and archaeology. Tooth volume has been recognized as a valuable feature for sex estimation. However, dental morphology exhibits population-specific variations, which remains underexplored in the northern Han Chinese population. Furthermore, manual segmentation of cone-beam computed tomography (CBCT) images is prone to subjectivity and error, and conventional modeling approaches may offer limited predictive accuracy. This study aimed to address these limitations by integrating automated artificial intelligence (AI) segmentation with multiple machine learning algorithms to enhance objectivity and predictive performance in sex prediction. A cohort of 398 CBCT images was analyzed using a fully automated deep learning system for tooth segmentation, and a final cohort of 357 samples (185 females, 172 males) was retained. Volumetric data for teeth were automatically calculated, with missing values imputed via multiple imputation by chained equations (MICE). Four machine learning algorithms were applied to build binary classification models for sex estimation. Hyperparameter optimization was achieved through nested cross-validation, and model performance was evaluated on a test set using a comprehensive set of metrics. All 16 measured teeth showed significantly differences in volume between sexes, with males consistently showing larger mean volumes across all tooth types compared to females. Nested cross-validation showed that all models exhibited promising performance for sex estimation with mean ACC above 0.77 and mean AUC values at or above 0.85. On the test set, the models achieved accuracies ranging from 0.803 to 0.859 and AUCs from 0.893 to 0.903. SHAP interpretability analysis highlighted canines as having the greatest impact on predictions. This study is the first to demonstrate the significant sexual dimorphism of tooth volumes in a north Chinese population. We utilized an AI-based automated segmentation accompanied with machine learning modeling pipeline to accurately estimate sex using tooth volume features, offering a valuable approach for forensic and anthropological applications.
The aim of this study was to adapt the NOSE instrument into the Arabic language using a cohort that reflects the linguistic and cultural diversity of Middle Eastern nationalities and dialects. Additionally, the study aimed to evaluate score distribution and propose a preliminary severity categorization using a Middle Eastern cohort. The NOSE scale was translated into Arabic using a forward–backward translation process. Adult native Arabic speakers (≥ 16 years) were recruited from Otolaryngology and Facial Plastic Surgery clinics. Participants included patients with nasal obstruction and asymptomatic controls with normal endoscopic examinations. Construct validity was assessed by correlations with patient-reported visual analog scale (VAS) scores (0–10 scale, where 0 indicates no obstruction and 10 indicates maximal obstruction). Internal consistency, test–retest reliability, responsiveness to surgical intervention, and score discrimination between groups were evaluated. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal cutoff score. A total of 235 participants completed the Arabic NOSE scale, including 182 patients with nasal obstruction and 53 normal controls. The Arabic NOSE score was significantly higher in patients with nasal obstruction than in controls (62.9 ± 22.2 vs. 7.8 ± 7.6; p < 0.001). The scale demonstrated excellent internal consistency (Cronbach’s α = 0.92) and strong test–retest reliability (r = 0.93). Arabic NOSE scores correlated strongly with patient-reported VAS severity (r = 0.90) and surgeon-assessed severity (r = 0.83). ROC analysis identified a cutoff score of < 25 as optimal for distinguishing normal from symptomatic participants (sensitivity 96.2
