Head & Face Medicine最新文献

Objective: Excessive intake of electrolyte sports drinks (ESDs) among adolescents and athletes is associated with dental erosion due to their low pH, while their sugar content increases the risk of dental caries. This study aimed to evaluate and compare the protective effects of incorporating either L-arginine or Salvadora persica (Miswak) extract into an ESD on enamel surface properties.

Materials and methods: Extracted human premolars were randomly assigned to three groups (n = 6): (1) plain ESD, (2) ESD with 1% L-arginine (Arg-ESD), and (3) ESD with 10% Salvadora persica extract (Mis-ESD). Each specimen was immersed in its respective solution for 5 min daily over 7 days. Post-treatment assessments included enamel microhardness (VHN), surface roughness (Sa), colour change (ΔE), Ca/P ratio, and scanning electron microscopy (SEM) for surface morphology. A taste acceptability survey was conducted in adult volunteers. Statistical analysis used one-way ANOVA (α = 0.05). In addition, a small panel of adult volunteers (n = 20) evaluated the taste acceptability of the modified formulations after providing informed consent.

Results: Both Arg-ESD and Mis-ESD significantly increased enamel microhardness and reduced surface roughness compared to plain ESD (P < 0.01), with Mis-ESD showing the greatest improvements. Mis-ESD also enhanced colour stability (P < 0.001). SEM images confirmed preservation of enamel structure, particularly in Mis-ESD specimens. Taste testing indicated good palatability for both modified formulations.

Conclusion: Incorporating Salvadora persica extract into ESDs significantly improved enamel resistance to erosion and enhanced aesthetic properties. Miswak-enriched ESDs could serve as a preventive option for dental erosion.

Clinical relevance: Formulating ESDs with Salvadora persica may reduce their erosive potential while preserving taste acceptability, offering a novel, consumer-friendly strategy to protect enamel in high-risk populations.

Objectives: This work aimed to investigate the impact of folic acid or multivitamin containing folic acid supplementation during pregnancy on morphology and mineral content of enamel structure in deciduous teeth.

Materials and methods: 54 exfoliating deciduous upper central incisors were extracted from children between the ages of 6 and 8. Teeth were divided according to the maternal use of micronutrients into three groups (n = 18), group I: no use; group II: folic acid; and group III: multivitamin containing folic acid. Specimens' ultrastructure was examined by scanning electron microscope (SEM). Elemental analysis was done using energy-dispersive X-ray spectroscopy (EDX), then statistical evaluation was conducted.

Results: SEM analysis revealed a uniform enamel surface morphology, indicating a level of resistance to normal physiological enamel wear in groups II and III in contrast to group I. These findings were affirmed by EDX assessment where enamel surface revealed statistically significant higher values for calcium, and phosphorus in groups II and III relative to group I. Additionally, carbon content revealed statistically significant higher values in group I than those of groups II and III, suggesting more susceptibility of hydroxyapatite crystals to dissolution in group Ι.

Conclusion: Maternal micronutrients supplementation was linked with the preservation of enamel structure in primary teeth. This indicates enhanced enamel resistance to mineral loss during normal physiological dental wear. The findings of this preliminary study highlighted the importance of prenatal multivitamin supplementation as a strategy in preventive dentistry.

Study design: We conducted a prospective cohort study comparing interobserver reliability of 2 different 3D scanning measurement methods following dermal filler therapy in oral cleft patients.

Objective of the study: The objective of the study was to compare the interobserver reliability of 2 different assessment methods of 3D facial scan data.

Methods: We studied 10 oral-cleft patients prospectively who underwent dermal filler therapy in the oral region by a single oral-surgeon using a modified injecting technique with 27 gauge 25 mm micro-cannula between 2021 and 2023. 3D facial scans were made before the treatment procedure and during follow-up visits and were used for analysis. The interbody fusion was scored on these 3D images using the 2 classification systems (Method 1, Method 2) by 3 experienced orthodontic specialists all of whom were blinded to clinical data and outcome.

Results: Of the 2 classifications included in the current study, all classifications had a high interobserver agreement.

Conclusion: The 2 assessment methods used in this study showed high interobserver reliability so we can conclude that, the applied methods may provide as a validation in the outcome of dermal filler therapy. However, we suggest that further refinements may be required to achieve a reliable and consistent assessment of 3D facial scan analysis after dermal filler therapy in oral cleft patients.

Background: To develop a deep learning-based model that is capable of automatically segmenting teeth in cone-beam computed tomography (CBCT) images and generating auxiliary diagnostic reports.

Methods: A two-stage pipeline model comprising a segmentation module and a classification module was designed. The segmentation module integrates the 3D TransUNet model and fine-tuned nnU-Netv2 framework to predict tooth location and numbering. The classification module uses a 3D DenseNet169 model to assess tooth conditions and detect dental diseases. A total of 450 CBCT datasets were collected, preprocessed, and annotated with tooth contours, numbering, and disease status. The dataset was randomly split into training, validation, and test sets at a 3:1:1 ratio. The model's performance was then evaluated by using multiple quantitative metrics.

Results: The segmentation module achieved a Dice similarity coefficient (DSC) of 0.9409 and an average symmetric surface distance (ASSD) of 0.5011. The classification module, which is based on the 3D DenseNet169 model, achieved an accuracy of 0.9297 and an F1-score of 0.9252.

Conclusions: The two-stage pipeline model effectively integrates automated tooth segmentation and auxiliary diagnosis. The segmentation module demonstrates high accuracy, while the classification module exhibits strong diagnostic performance. The final output seamlessly combines segmentation and the diagnostic results, enabling the automated generation of structured auxiliary diagnostic reports with tooth numbering. By significantly enhancing the diagnostic efficiency, the proposed method offers substantial support for clinical decision-making in dentistry and holds great potential for real-world applications.

Background: One component of facial aesthetics is a harmonic facial profile. Orthodontic treatment and/or orthognathic surgery can affect the facial profile by influencing the underlying hard-tissue structure. The aim of this study was to improve the prediction of treatment outcomes by evaluating 3D perioral frontal and buccal soft-tissue changes after protrusion of incisors in ten young adults.

Methods: The participants had neutral occlusion and physiologic incisor inclination. 3D-printed acrylic veneers with thicknesses of 1-4 mm were bonded to the labial surfaces of the upper and lower incisors. 3D face scans with and without veneers were taken to evaluate perioral soft tissue changes using 44 landmarks. Face scans were superimposed at the forehead. Soft-tissue changes were evaluated using linear mixed-effects models.

Results: Interrelations between simulated incisor protrusion and the resulting soft-tissue changes were statistically highly significant (p < 0.005) and nearly linear. Simulated isolated upper incisor protrusion caused greatest forward positioning of the labrale superius convex [LS-con] landmark-by 0.65 mm per millimetre of veneer thickness. Lower lip displacement at the labrale inferius convex [LI-con] landmark was greatest when both upper and lower incisors were protruded (0.76 mm/mm). The vertical lip displacement rate for simulated upper and lower incisor protrusion was 0.12 mm/mm upward positioning of LS-con and 0.66 mm/mm downward positioning of LI-con. Mixed-effects models revealed that a 1-mm increase in initial lip thickness at the labrale superius reduces soft-tissue displacement by about 8% of the simulated tooth movement.

Conclusions: Anterior positioning of incisors leads to predictable, direction-specific changes in perioral soft tissues. The magnitude and pattern of soft-tissue responses vary with the combination of upper and lower incisor movement and individual lip thickness. These findings may support clinical planning in orthodontic and/or orthognathic treatments.

Background: This study aimed to assess the three-dimensional facial morphological changes and acquire quantitative relationship between facial landmarks and zygion point to analyze the overall facial soft tissue impact of extraction and non-extraction orthodontic treatment.

Methods: A total of 21 extraction (19.5 ± 9.2 years) and 21 non-extraction (26.2 ± 9.1 years) versus consecutive patients were enrolled. The pretreatment and posttreatment 3D facial scans were captured using the FaceSCAN3D optical system. After establishing the coordinate system and manually placing landmark, fourteen linear and twelve angular measurements were obtained. Additionally, sixteen projection distances between landmarks and the Zygion point were measured. Color-coded displacement maps were conducted through surface registration for visualization and qualitatively assessed facial changes.

Results: In extraction group, inter-cheek width (2.60 ± 5.64 mm, P = 0.050) and mouth width (1.92 ± 3.89 mm, P = 0.040) increased, while upper lip fullness (-0.88 ± 1.11 mm, P = 0.003), lower lip fullness(-0.55 ± 1.21 mm, P = 0.050), and Li-N'-Pg' angle (-1.55 ± 1.09°, P < 0.001) decreased (T1-T0). As for quantitative measurements, the backward movement of landmarks in paranasal area (bilateral Al [nasal ala]: -1.14 ± 1.84 mm and -1.14 ± 1.47 mm, P = 0.010 and P = 0.002, respectively; bilateral Subal [subnasal ala]: -1.23 ± 2.18 mm and -1.25 ± 1.46 mm, P = 0.018 and P = 0.001, respectively) was observed. In the cheek area, significant changes were found in: left Ck-i [cheek-inner]: -1.40 ± 2.18 mm, P = 0.008; right Ck-m (cheek-middle): -2.32 ± 2.71 mm, P = 0.001), right Ck-o [cheek-outer]: -2.65 ± 4.05 mm, P = 0.007). In the lip area, changes were noted in: (bilateral Chp [chresta philtri]: P < 0.001, bilateral Ch [cheilion]: P < 0.001, Ls (labrale superius]: P = 0.002, Stm [stomion]: P < 0.001, and Li [labrale inferius]: P = 0.002. All changes observed were measured relative to the Zygion point in extraction group.

Conclusions: This study reveals the effects of extraction and non-extraction treatments on the lip, cheek and paranasal areas. Significant differences were found in the linear and angular measurements. The lower lip retraction was more pronounced in the extraction group. A new quantitative method for measuring facial landmarks was established. Inward and downward movement of facial landmarks was observed after extraction treatment.

Trial registration: The protocol of this study (PKUSSIRB-202392145) was registered at the Chinese Clinical Trial Registry (Chictr.org.cn) with the identifier ChiCTR2000034288 (01/07/2020).

Background: Orbital exenteration (exenteratio orbitae) is a disfiguring procedure performed with tumor resection. Rapid realization of an implant-retained craniofacial prosthesis with a secure fit for an active life is essential to restore quality of life. Osseointegrated implants are commonly used for maxillofacial rehabilitation. The precise positioning of these implants is more difficult in cases of reduced bone availability, but it enables anaplastologists to achieve an unobtrusive restoration.

Methods: After computed tomography (CT) scans of 13 cadaver heads, 104 craniomaxillofacial (CMF) implants were digitally planned. Using a split-face study design, one periorbital side was treated with customized surgical guides and one side was operated freehand. The digital evaluation of position, axis, and insertion depth compared to the digital planning was conducted for 78 periorbital implants using digital evaluation of a postoperative CT scan to measure the linear and angular deviation from preoperative planning.

Results: The linear deviation in 3D (p = 0.0105), drilling depth (p = 0.0013), and angular deviation (p = 0.0004) were significantly greater in the freehand group than in the guided computer-assisted implant surgery (CAIS) group.

Conclusion: Digital planning enables the available bone support to be preoperatively estimated. CAIS with surgical guides offers significantly more accurate results for CMF implant placement than a freehand transfer of digital planning. Guided CAIS requires a larger surgical approach and therefore fails to achieve the goal of a minimally invasive technique.

Background: Orthognathic surgery is frequently performed to correct dentofacial deformities and is known to alter the upper airway morphology. This study aimed to analyze volumetric changes in the upper airway following mono- and bimaxillary surgery using virtual surgical planning, with a specific focus on the minimal cross-sectional area (mCSA) and total upper airway volume (TUAV).

Methods: In this retrospective study, 81 patients with Angle Class II or III malocclusions underwent either mandibular advancement (MA), maxillomandibular advancement (MMA), mandibular setback, or a combination of mandibular setback with maxillary advancement. Surgical planning was performed using IPS CaseDesigner® software. Pre- and postoperative CBCT scans were analyzed to assess changes in mCSA and TUAV. Displacement distances were measured for both jaws, and statistical analysis was performed using paired t-tests and Pearson correlation.

Results: MA and MMA in Class II patients resulted in significant increases in mCSA (p = 0.0048 and p = 0.0005, respectively) and TUAV (p = 0.0346 and p = 0.01, respectively). In contrast, mandibular setback in Class III patients showed non-significant decreases in airway parameters, while bimaxillary surgery produced slight, non-significant increases. A mandibular setback of less than 4.05 mm was not associated with a relevant reduction in airway volume.

Conclusion: MA and MMA significantly increase upper airway dimensions and are effective treatment strategies for oropharyngeal airway deficiencies in Class II patients. Minor mandibular setbacks (< 4.05 mm), especially when combined with maxillary advancement, appear to preserve airway volume in Class III patients. These findings highlight the importance of individualized virtual planning to optimize both functional and aesthetic outcomes, while recognizing the limitations of using static CBCT imaging to assess dynamic airway function.