Head & Face Medicine最新文献

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.

Objectives: This study aimed to evaluate the antibacterial and antifungal efficacy, as well as postoperative pain levels, following non-surgical retreatment of single-rooted teeth using tricalcium silicate- or calcium hydroxide-based intracanal dressings.

Materials and methods: Forty-nine patients diagnosed with apical periodontitis were randomly assigned to two groups: tricalcium silicate (n = 25) and calcium hydroxide (n = 24). Microbiological samples were obtained before instrumentation (S1), after chemo-mechanical preparation (S2), and 10 days post-medication (S3). Total bacterial load and Candida albicans levels were quantified using qPCR. Postoperative pain was assessed on days 1, 3, 5, 7, and 10.

Results: No significant differences were found between the groups in demographic variables. The calcium hydroxide group showed a significantly greater reduction in total bacterial load in S3 samples. No significant differences were observed between groups regarding C. albicans levels or postoperative pain at any time point. However, a significant reduction in pain was noted on day 1 compared to baseline in the calcium hydroxide group.

Conclusions: Both materials were effective in reducing microbial load; however, calcium hydroxide demonstrated superior antibacterial efficacy. Antifungal activity and postoperative pain outcomes were comparable between the groups.

Trial registration: This trial was registered at Clinicaltrials.gov on 15/01/2025 (NCT06779370).

Objectives: We aimed to compare the intra- and interobserver agreements of postgraduate students in selecting tooth color using various conventional or digital tools.

Methods: Color selection was performed by four postgraduate students. Prior to the study, the students attended a lecture for calibration. Tooth color was assessed on the maxillary central incisors of 32 healthy patients. Visual color selection was performed using VITA Classical (VC) and VITA 3D (V3D) color scales. Digital color selection was performed using VITA Easyshade V and Canon D80 digital camera. The enamel (incisal) and dentin (cervical) from an anterior composite resin set were temporarily adhered to the facial surface of the incisor using the button technique. Digital photographs were captured and color selection was performed. Enamel (E1) and dentin (D1) colors were created based on the original photographs. The enamel color (E2) was selected by converting the photographs to black and white. The dentin colors (D2) were chosen by increasing the contrast of the images. Data were statistically analyzed using the intraclass correlation coefficient (ICC) test.

Results: Poor or moderate agreement was observed between the VC-V3D, VC-VE, and V3D-VE in terms of intraobserver agreements. Conversely, the intraobserver agreements between E1 and E2 were good for all four observers. The ICC results for the interobserver agreement were good for evaluations of photographs alone, whereas the agreement was poor for the other methods.

Conclusions: Color selection in the aesthetic region can be safely performed using the button technique based on original digital photographs.

Clinical relevance: Digital dental photography is important in improving the accuracy of clinical tooth color selection.

Study objectives: Functional orthopedics induces mandibular advancement caused by neuromuscular adaptations. These adaptations can affect the position of the hyoid bone and may contribute to the amount of skeletal outcomes. The skeletal response is triggered by the quality and quantity of growth as well as muscular reactions. The aim of this clinical trial was to evaluate the hyoid bone position before and after functional orthodontic treatment.

Methods: This prospective cohort study included 31 patients (mean age: 12.3 ± 0.9 years) with skeletal class II meeting the following inclusion criteria: ANB > 4°, > ½ Class II molar relationship, overjet > 6 mm, neutral/horizontal growth pattern, and CVMS II-III. All patients were treated with the Sander Bite Jumping Appliance (BJA) with wear time monitored through microsensors. Lateral cephalograms were taken at baseline (t0) and after 1 year (t1). Linear and angular hyoid measurements were analyzed. Statistical analysis was performed using IBM SPSS (v29.0.2.0), employing paired t-tests and an exploratory post hoc grouping based on total mandibular length changes (Δco-pg), with significance set at p < 0.05.

Results: BJA therapy resulted in a significant more superior and anterior position of the hyoid in all patients. A greater increase in Δco-pg at t1 was associated with a more pronounced hyoid shift, while patients with a less Δco-pg showed a more inferior hyoid position at t0 and a greater tendency towards a vertical growth pattern.

Conclusion: A more inferior initial hyoid position was associated with limited mandibular advancement, suggesting a potential anatomical link to airway physiology, warranting further investigation into its implications for OSA risk.

Clinical trial registration: German Clinical Trials Register (DRKS); URL: http://www.germanctr.de; Identifier: DRKS00021090; registration date: 12.03.2020.

Objective: To analyse the characteristics of electrically evoked middle latency responses (EMLR) in patients with profound sensorineural hearing loss (SNHL) and tinnitus.

Methods: Thirty adults with profound SNHL and tinnitus who underwent cochlear implantation were selected as the tinnitus group, and 15 patients with profound SNHL but without tinnitus served as the control group. Preoperative data were retrospectively analysed. Electrically evoked middle latency responses were recorded intraoperatively, and the electrophysiological characteristics were compared between groups. Changes in tinnitus were assessed using the Tinnitus Handicap Inventory (THI), and correlations between EMLR parameters and THI scores were analysed.

Results: No postoperative complications occurred in any of the patients. Electroauditory responses were successfully elicited in all 45 patients. Intraoperative EMLR showed increased Na-Pa amplitude and delayed Pa latency, with significant differences observed between the tinnitus and control groups (P < 0.05). One year after cochlear implantation, the average comfort level (C value) and the EMLR threshold showed a significant linear correlation (r = 0.915, P < 0.01). Postoperative THI scores showed a significant decrease (P < 0.05) compared with preoperative scores. A significant correlation was found between the intraoperative EMLR Na-Pa wave amplitude and THI change at 1 year (r = 0.815, P < 0.05), with an area under the ROC curve of 0.673 (P = 0.002).

Conclusion: The intraoperative EMLR waveform of patients with profound SNHL and tinnitus is significantly different from that of patients without tinnitus. Cochlear stimulation effectively inhibits tinnitus, and EMLR provides an objective tool for evaluating tinnitus and optimising its management. However, further studies with larger sample sizes are needed to validate these preliminary findings.

Background: This cohort study aimed to evaluate the relationship between sella turcica (ST) morphology and dentofacial anomalies three-dimensionally (3D).

Methods: Cone beam computed tomograms (CBCTs) and computed tomography scans (CTs) of 90 adults (46 women; age 28.1 ± 11.3 years) were analyzed. Dentofacial anomalies were evaluated (1) sagittally regarding skeletal classes (Wits appraisal), (2) vertically regarding the inclination of the jaws (maxillomandibular plane angle), and (3) transversally regarding skeletal symmetry (menton deviation from midsagittal plane). Sella morphology was assessed (a) linearly by ST-length, -width, -height, -diameter, and position to nasofrontal suture (CB); and (b) volumetrically by total, anterior, and posterior volume (Vol_T, Vol-A, Vol_P). Five porcine skulls were scanned by CBCT, CT, and micro-CT for method validation.

Results: CBCT and CT both underestimated the ST volume compared to the volume measured with micro-CT. ST morphology differed significantly between the skeletal classes. Individuals with skeletal class I showed higher ST length than participants with skeletal class II (p = .024). Vol_T and Vol_A were higher in class II than in class III (p = .047; p = .019). Vol_A correlated with the Wits appraisal (r = .337, p < .001). Vertical and transversal jaw relation showed no correlation with ST variables. ST-width and CB were significantly higher in men than women (p = .004; p < .001).

Conclusion: 3D-diagnostics of ST morphology enabled conclusions about underlying dentofacial anomalies. Vol_A seemed to be a relevant marker based on its correlation and class-specific volumes. Future research could help to identify this as prognostic factor of developing anomalies.