Bisphenol A release from CAD/CAM splint materials.

This study aimed to investigate the bisphenol A (BPA) release from four CAD/CAM splint materials: three polycarbonate-based (DD BioSplint C, Splint Plus Biostar, Temp Premium Flexible) and one polymethylmethacrylate-based (Temp Basic) material. From each material, ten cylindrical samples (n = 40) were immersed in high-performance liquid chromatography (HPLC) grade water following ISO 10993-12 and incubated for 24 h in an incubation shaker at 37°C and 112 rpm. Following BPA derivatization, analysis was performed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). After 24 h of incubation, all investigated materials released significant amounts of BPA compared to water blanks. The material-dependent elution increased in the following order: DD BioSplint C < Splint Plus Biostar < Temp Basic < Temp Premium Flexible. Subtracting extraneous BPA, the concentrations ranged between 2.27 ng/mL and 12.65 ng/mL. After extrapolating the concentrations in relation to the average surface area of occlusal splints, the amount of BPA per mL exceeded the Tolerable Daily Intake (TDI) set by the European Union for a person weighing 70 kg by 1.32-6.16 times. Contrary to the release from previously investigated materials, BPA elution from CAD/CAM splint materials was highly elevated. Considering the increasing adaptation of CAD/CAM techniques, elution from them may represent a relevant BPA source in daily dental practice.

Hand eczema symptoms, exposures and skin care in orthodontics : A national, cross-sectional questionnaire-based survey.

OBJECTIVES: Occupational hand eczema is a common inflammatory skin condition among healthcare professionals. Orthodontists are frequently exposed to a variety of irritating and allergenic substances, and therefore they belong to a predisposed group to develop hand eczema. However, current data on the prevalence and predisposing factors among orthodontists to provide adequate prophylaxis are lacking. METHODS: An anonymous online survey was conducted in Germany between January and February 2023 and distributed to 2402 orthodontists. The questionnaire addressed general information on current skin status, as well as occupational skin exposure and skin care. RESULTS: A total of 209 orthodontists responded to the survey. Seventy-four percent reported experiencing hand eczema-specific symptoms within the last 12 months, with 24% describing moderate and 10% describing severe symptoms. The average daily glove wearing time was stated to be 6 ± 2 h. The most frequently reported triggers at work were frequent hand washing (62.7%) and hand disinfection (59.1%). Among all the respondents, 22.6% stated not using either barrier cream or moisturizer. CONCLUSIONS: This study showed a high prevalence of hand eczema symptoms among orthodontists, which is probably due to frequent disinfection, hand washing, and contact with allergens such as acrylates. In this professional group especially, against a background of future increasing acrylate and epoxy resin exposures due to in-office three-dimensional printing processes, timely education and skin protection could decisively counteract the pathogenesis of hand eczema.

How to register static occlusion - Correlation of contemporary techniques.

Statement of problem: A working knowledge of the analytical capacities of contemporary registration methods is essential for prosthetic treatment; however, there is a paucity of studies which coherently investigate the capabilities and limitations of the various diagnostic procedures utilized for prosthetic occlusion. Purpose: The present prospective clinical study aimed to evaluate the similarities and differences among contemporary registration methods through comparative analysis. Material and methods: The habitual static occlusion of 19 healthy individuals (14 women; mean age ± standard deviation, 30.8 ± 4.8 years) was analyzed 3 times a day, using shimstock foil, occlusal foil, wax registration, silicone registration, and computerized registration. The procedures were repeated after 14 days. Statistical analyses included all registrations referencing the first measurement point to assess the mean values of antagonistic contacts and the differences between these measurements. Pearson's and Kendall's correlation analyses were performed as part of the coherent mixed logistic regression model, and marginal probabilities were calculated using the registration technique and repeated measurements. Results: Strong correlations were found among the various registration techniques. The largest effect sizes were observed among the wax, silicone, occlusion foil, and computerized registrations (r = 0.95, P < 0.001 to r = 0.62, P < 0.001), while the lowest effect sizes were found for shimstock correlations (τ = 0.41, P < 0.001 to τ = 0.27, P < 0.001). Occlusal changes per maxillary arch were observed referencing the first measurement time with wax registration (P < 0.001; 7.4%), shimstock foil (P < 0.001; 13.8%), computerized registration (P < 0.001; 20.3%), silicone registration (P = 0.009; 66.3%), and occlusion foil (P < 0.001; 98.8%). Occlusal changes per maxillary tooth were observed from the first incisor (P < 0.001; 5.7%) to the third molar (P < 0.001; 18.1%). Conclusions: The results of the present study revealed that there are strong overall correlations among the various contemporary registration techniques. The different affinities of the techniques used to register occlusal changes, however, showed differences in the measurement techniques, which should be neither over- nor underestimated. The differential tendencies of teeth to change should be considered, even if a hypervariable system is assumed.

Antibacterial coating of orthodontic elastomeric ligatures with silver and bismuth nanofilms by magnetron sputtering: A feasibility study.

OBJECTIVES: Magnetron sputtering was evaluated to equip surfaces of orthodontic elastomeric ligatures with silver and bismuth nanofilms. MATERIAL AND METHODS: Antibacterial properties were evaluated by the adhesion of Streptococcus mutans. Polyurethane-based elastomeric ligatures were coated with silver and bismuth nanofilms via direct current magnetron sputtering. Surface roughness (Ra ) and surface-free energy (SFE) were assessed. Coated specimens were incubated with S. mutans for 2 h. Adhering bacteria were visualized by Hoechst staining and quantified by an ATP-based luminescence assay. One-way analysis of variance with Tukey post hoc testing and Pearson correlation analysis were performed (p < .05) to relate bacterial adhesion to surface roughness and surface-free energy. RESULTS: Elastomeric ligatures were successfully coated with silver and bismuth nanofilms. Ra was significantly reduced by silver coating. Silver and bismuth coatings showed significantly higher SFE than controls. Adhesion of S. mutans was significantly decreased by silver coating. No correlation between bacterial adhesion and SFE was found. Correlation between bacterial adhesion and Ra was positive but not statistically significant. CONCLUSIONS: Magnetron sputtering proved to be a feasible method to equip orthodontic elastomeric ligatures with silver and bismuth nanofilms. Silver coatings of elastomeric ligatures may reduce white spots and carious lesions in orthodontic patients. Future research is required to stabilize coatings.

Reliability of landmark identification for analysis of the temporomandibular joint in real-time MRI.

BACKGROUND: Real-time magnetic resonance imaging (rtMRI) is essential for diagnosing and comprehending temporomandibular joint (TMJ) movements. Current methods for tracking and analysis require manual landmark placement on each acquisition frame. Therefore, our study aimed to assess the inter- and intra-rater reliability of placing cephalometric landmarks in frames from a dynamic real-time TMJ MRI. MATERIAL AND METHODS: Four real-time MRIs of the right TMJ were taken during mandibular movement at ten frames per second. Seven dentists identified ten landmarks on two frames (intercuspal position-ICP-and maximum mouth opening-MMO) twice at a two-week interval, yielding 112 tracings. Six typical cephalometric measurements (angles and distances) were derived from these landmarks. The reliabilities of landmarks and measurements were evaluated using distance-based (dbICC), linear mixed effect model intraclass correlation (lmeICC), and standard ICC. RESULTS: The average inter-rater reliability for the landmarks stood at 0.92 (dbICC) and 0.93 (lmeICC). The intra-rater reliability scores were 0.97 and 0.98. Over 80% of the landmarks showed an ICC greater than 0.98 (inter-rater) and over 0.99 (intra-rater). The lowest landmark ICC was observed for the orbitale and the oblique ridge of the mandibular ramus. However, the cephalometric angle and distance measurements derived from these landmarks showed only moderate to good reliability, whereas the reliability in the frames with ICP was better than those with MMO. Measurements performed in the ICP frame were more reliable than measurements in the MMO frame. CONCLUSION: While dentists reliably localize isolated landmarks in real-time MRIs, the cephalometric measurements derived from them remain inconsistent. The better results in ICP than MMO are probably due to a more familiar jaw position. The higher error rate of the TMJ measurements in MMO could be associated with a lack of training in real-time MRI analysis in dentistry.

Assessment of oropharyngeal respiratory volume and sleep apnoea scores using peripheral arterial tonometry may improve diagnosis and treatment planning of combined dysgnathia therapy approaches.

BACKGROUND: Increased daytime sleepiness is a frequently reported symptom in patients with pronounced dysgnathia. OBJECTIVES: This study investigated possible correlations using home peripheral arterial tonometry (PAT) and oropharyngeal airway volume determination in patients with dysgnathia and daytime sleepiness. METHODS: Twenty patients (13 male, median age 27.6 ± 6.8 years) with abnormal sleep history and 10 skeletal neutral configured controls (6 male, median age 29.5 ± 4.2 years) with normal sleep history were examined. Patients and controls were evaluated for apnoea-hypopnoea index (AHI), respiratory disturbance index (RDI), oxygen desaturation index (ODI), snoring volume (dB), total sleep time (TST) and REM-percentage (REM). Airway volumetry was measured via CBCT. Individual user experience for PAT was assessed using the User Experience Questionnaire (UEQ). RESULTS: Patients had significantly higher respiratory scores than controls. AHI increased 4.6-fold (p = .006), RDI 2.5-fold (p = .008) and ODI 6.4-fold (p < .001). Oropharyngeal volumes showed a 30% decrease (p = .003). dB, TST and REM showed no significant differences. AHI (r = -.51; p = .005), ODI (r = -.60; p < .001) and RDI (r = -.45; p = .016) correlated negatively with pharyngeal volume. Wits appraisal correlated negatively with oropharyngeal volume (r = -.47; p = .010) and positively with AHI (r = .41; p = .03) and ODI (r = .49; p = .007). dB and TST (r = -.49; p = .008) and REM and RDI (r = -.43; p = .02) correlated negatively. UEQ-KPI (2.17 ± 0.24) confirmed excellent usability of PAT. CONCLUSION: Patients with mandibular retrognathia and abnormal sleep history showed significantly higher respiratory indices and smaller oropharyngeal volumes than neutrally configured controls. The dygnathia severity directly influenced the risk of obstructive sleep apnoea.

Postoperative facial appearance of patients with extensive oral squamous cell carcinoma can be adequately preserved with in­house virtually planned mandibular reconstruction.

The present study aimed to assess the concordance of preoperative and postoperative hard and soft tissues in patients with advanced oral squamous cell carcinoma (OSCC) following virtual surgical planning (VSP) mandibular reconstruction. In the present study, a cohort of 32 patients with OSCC underwent in-house VSP, followed by guided mandibular reconstruction utilizing vascularized free tissue grafts sourced from the fibula or scapula. A morphometric analysis was conducted comparing preoperative and postoperative three-dimensional virtual models to evaluate discrepancies and identify potential risk factors associated with poor reconstruction outcomes. The outcome variables were the differences in root mean square (RMS) and mean surface distance (MSD) resulting from the application of an iterative closest point algorithm to the virtual data. The validity of soft tissue comparison data is limited due to its susceptibility to various confounding variables. The present study conducted a comprehensive re-evaluation of these variables. High tumor stage, positive N status and the use of adjuvant therapy contributed to more noticeable differences in preoperative and postoperative facial soft tissue appearance. The accuracy of postoperative bone reconstruction results was higher in patients who underwent neomandibular formation using a fibular graft compared with those who received a scapular graft. Preoperative and postoperative soft tissue analyses were conducted for comparison. The MSD showed a deviation of 3.2 mm (± 2.0 mm SD; range 1.3-9.5 mm), whereas the RMS was 5.3 (± 2.9 SD; range 2.1-14). In conclusion, in-house VSP and guided mandibular reconstructions can yield clinically accurate results, preserving patient appearance and offering the advantage of rapid feasibility.

Radiodiagnostics of standard orthodontic radiographs-dental and extradental incidental findings : Do we see everything we should see?

OBJECTIVES: The extent of undetected incidental findings in routine orthodontic radiographs is still unknown. However, incidental findings that are not in the primary focus of orthodontic diagnostics may be of high medical relevance. Therefore, this study aimed to analyse whether incidental findings are reliably detected and which parameters influence the orthodontist's assessment. METHODS: In a clinical cross-sectional study 134 orthodontists evaluated two orthopantomogram (OPT) and two lateral cephalogram (LC) radiographs each via a standardised online survey. The radiographs were previously examined by three dentists and one radiologist-in a pilot phase-regarding the number of incidental findings and subsequently defining as gold standard in a consensus procedure. The radiographs were presented consecutively, the number of incidental findings detected were noted and the individual findings could be described in free text form. RESULTS: Overall, 39.1% of the incidental findings were detected. The orthodontists' focus was primarily on the dental region. Here, 57.9% of incidental findings were detected, while 20.3% were detected in extradental regions (p < 0.001). A highly relevant finding of suspected arteriosclerotic plaque was detected in 7.5% of cases (OPT). Significantly more incidental findings were detected on OPTs than on LCs (OPT 42.1%, LC 36.0%, p < 0.001). As participants' length of professional experience increased, significantly more time was spent on the assessment (p < 0.001), correlating positively with the detection of incidental findings. CONCLUSIONS: Even in daily routine practice, attention must be paid to a thorough assessment of all radiographed regions. The factors time and professional experience can prevent practitioners from overlooking findings outside the orthodontic focus.

The Role of Augmented Reality in the Advancement of Minimally Invasive Surgery Procedures: A Scoping Review.

The purpose of this review was to analyze the evidence on the role of augmented reality (AR) in the improvement of minimally invasive surgical (MIS) procedures. A scoping literature search of the PubMed and ScienceDirect databases was performed to identify articles published in the last five years that addressed the direct impact of AR technology on MIS procedures or that addressed an area of education or clinical care that could potentially be used for MIS development. A total of 359 studies were screened and 31 articles were reviewed in depth and categorized into three main groups: Navigation, education and training, and user-environment interfaces. A comparison of studies within the different application groups showed that AR technology can be useful in various disciplines to advance the development of MIS. Although AR-guided navigation systems do not yet offer a precision advantage, benefits include improved ergonomics and visualization, as well as reduced surgical time and blood loss. Benefits can also be seen in improved education and training conditions and improved user-environment interfaces that can indirectly influence MIS procedures. However, there are still technical challenges that need to be addressed to demonstrate added value to patient care and should be evaluated in clinical trials with sufficient patient numbers or even in systematic reviews or meta-analyses.

Is CCL2 an Important Mediator of Mast Cell-Tumor Cell Interactions in Oral Squamous Cell Carcinoma?

In this study, we aimed to evaluate the influence of interactions between mast cells (MCs) and oral squamous cell carcinoma (OSCC) tumor cells on tumor proliferation and invasion rates and identify soluble factors mediating this crosstalk. To this end, MC/OSCC interactions were characterized using the human MC cell line LUVA and the human OSCC cell line PCI-13. The influence of an MC-conditioned (MCM) medium and MC/OSCC co-cultures on the proliferative and invasive properties of the tumor cells was investigated, and the most interesting soluble factors were identified by multiplex ELISA analysis. LUVA/PCI-13 co-cultures increased tumor cell proliferation significantly (p = 0.0164). MCM reduced PCI-13 cell invasion significantly (p = 0.0010). CC chemokine ligand 2 (CCL2) secretion could be detected in PCI-13 monocultures and be significantly (p = 0.0161) increased by LUVA/PCI-13 co-cultures. In summary, the MC/OSCC interaction influences tumor cell characteristics, and CCL2 could be identified as a possible mediator.

In Vivo Biofilm Formation on Novel PEEK, Titanium, and Zirconia Implant Abutment Materials.

The formation of biofilms on the surface of dental implants and abutment materials may lead to peri-implantitis and subsequent implant failure. Recently, innovative materials such as polyether-ether-ketone (PEEK) and its modifications have been used as abutment materials. However, there is limited knowledge on microbial adhesion to PEEK materials. The aim of this in vivo study was to investigate biofilm formation on the surface of conventional (titanium and zirconia) and PEEK implant abutment materials. Split specimens of titanium, zirconia, PEEK, and modified PEEK (PEEK-BioHPP) were manufactured, mounted in individual removable acrylic upper jaw splints, and worn by 20 healthy volunteers for 24 h. The surface roughness was determined using widefield confocal microscopy. Biofilm accumulation was investigated by fluorescence microscopy and quantified by imaging software. The surface roughness of the investigated materials was <0.2 µm and showed no significant differences between the materials. Zirconia showed the lowest biofilm formation, followed by titanium, PEEK, and PEEK-BioHPP. Differences were significant (p < 0.001) between the investigated materials, except for the polyether-ether-ketones. Generally, biofilm formation was significantly higher (p < 0.05) in the posterior region of the oral cavity than in the anterior region. The results of the present study show a material-dependent susceptibility to biofilm formation. The risk of developing peri-implantitis may be reduced by a specific choice of abutment material.

Evaluation of occlusal function during orthognathic therapy : A prospective clinical trial using a digital registration method.

OBJECTIVES: Reduced occlusal function is a main characteristic of orthognathic patients. The present study aimed to investigate the extent of therapy-induced functional improvements in occlusal function using a digital diagnostic method. METHODS: This prospective clinical study included 41 orthognathic patients (24 women and 17 men, median age 27.26 ± 8.2 years) and 10 control patients (5 women and 5 men, median age 29.8 ± 13.5 years) with neutral skeletal and dental configurations. The patients were divided into classes I, II and III based on their cephalometry. Digital occlusal registrations in habitual occlusion in an upright sitting position were taken before (T1) and after (T2) therapy using the T­Scan Novus (Tekscan, South Boston, MA, USA) application. RESULTS: Class II and III patients showed a significantly less efficient occlusal pattern than the untreated controls regarding total antagonism (p < 0.001), time of occlusion (p = 0.004), occlusal asymmetry (p = 0.001), anterior antagonism (p < 0.001) and posterior antagonism (p < 0.001). After therapy, the occlusal pattern increased in both therapy groups, where class III patients became indistinguishable from the controls, and class II patients differed only in posterior antagonism (p = 0.035). CONCLUSIONS: The digital occlusal registration method proved to be a useful diagnostic tool and provided new insights into therapeutic effects in orthognathic patients. By precisely adjusting the occlusal function, masticatory performance improved significantly. CLINICAL RELEVANCE: Severe malocclusion leads to a significantly lower masticatory performance for patients, which can be improved by orthognathic therapy and captured by digital occlusal registration.

A Pilot Study on Monomer and Bisphenol A (BPA) Release from UDMA-Based and Conventional Indirect Veneering Composites.

This study aimed to investigate the release of common monomers from conventional (Dialog Vario, Enamel Plus HFO) and UDMA-based indirect veneering composites (VITA VM LC, GC Gradia). Ten cylindrical samples of each material were prepared (n = 40), immersed in HPLC grade water, and incubated for 24 h in an incubation shaker at 37 °C and 112 rpm. Extraction was performed following ISO 10993-12 and monomers were detected and quantified by HPLC-MS/MS. In all the samples, urethane dimethacrylate (UDMA) and bisphenol A (BPA) were quantifiable. Compared to water blanks, BPA levels were only elevated in the eluates from conventional composites. In all other samples, concentrations were in the range of extraneous BPA and were therefore clinically irrelevant. Low concentrations of Bisphenol A-glycidyl methacrylate (BisGMA) were found in one BPA-free composite and in both conventional materials. Statistical analyses showed that BPA-free materials released significantly less BisGMA and no BPA, while UDMA elution was comparable to elution from conventional materials. All measured concentrations were below reported effective cytotoxic concentrations. Considering these results, the substitution of BPA-derivatives with UDMA might be beneficial since BPA-associated adverse effects are ruled out. Further studies should be enrolled to test the biocompatibility of UDMA on cells of the oral environment.

Diagnostic value of routine dental radiographs for predicting the mandibular canal localization validated by cone-beam computed tomogram measurements.

OBJECTIVES: To test the hypothesis that routine dental radiographs can be used to draw conclusions regarding the mandibular canal (MC) localization. MATERIAL AND METHODS: A total of 108 radiographs (36 orthopantomograms [OPTs], 36 lateral cephalograms [LCs], and 36 cone-beam computed tomograms [CBCTs]) of 36 patients were analyzed. Statistical analysis included all cephalometric parameters obtained by OPTs, LCs, and CBCTs. Potential influencing parameters were calculated using linear and logistic regression with a backward removal algorithm. For predictability of MC localization, parameters were correlated using Pearson's correlation. RESULTS: The MC ran along the lingual half (n = 24) twice as often as in the buccal half (n = 12) in the population studied. The position was always symmetrical contralaterally. No sex-specific influence was observed (p = .34). Lingual and buccal MC courses were statistically significantly correlated to increased and decreased jaw angles (LC/OPT), respectively (p = .003; r = -.48/p = .010; r = -.42). An increased jaw angle was significantly correlated with a more cranial MC position (p = .013; r = -.41); a deep and distal bite position was significantly correlated with a caudal and buccal MC position (p = .004; r = -.47/p = .001; r = .57). Moreover, an increase of 1 point in the Hasund score predicted an increased probability of a buccal MC position by 18.6%. The jaw angle analyzed in OPT and LC images were positively correlated (r = .89, p < .001). CONCLUSIONS: Routine dental radiographs provide informative guidance on the location of the MC in the vertical and transverse levels. This finding could be used in the initial consultation and treatment planning to consider more invasive diagnostic methods further down the line.

Time of day-dependent deviations in dynamic and static occlusion: A prospective clinical study.

STATEMENT OF PROBLEM: The registration of dental occlusion is essential for prosthodontic treatment. However, studies on time-dependent changes of static and dynamic occlusion that may affect definitive restorations are lacking. PURPOSE: The purpose of this prospective clinical study was to use conventional and digital occlusal registration techniques to evaluate time-dependent fluctuations in static and dynamic occlusion. MATERIAL AND METHODS: The static and dynamic occlusion of 19 healthy individuals (14 women and 5 men with a mean ±standard deviation age of 30.8 ±4.8 years) was examined 3 times a day using occlusal foil (12-µm occlusion foil) and a digital sensor (T-Scan III). The procedure was repeated after 14 days. The statistical analysis covered all registrations referencing the first measurement point to assess occurring differences, and changes per tooth and arch were determined (α=.05). Potential influencing factors were calculated by using mixed logistic regression. Marginal probabilities were calculated considering the registration technique and the time of measurement. RESULTS: Significant differences were found between registered occlusal patterns and the different registration techniques. Occlusal changes per maxillary dental arch were observed with static foil registration (P<.001; 98.8%), left laterotrusion foil registration (P=.001; 29.6%), right laterotrusion foil registration (P=.001; 29.6%), static sensor registration (P<.001; 20.3%), left laterotrusion sensor registration (P=.001; 71.7%), and right laterotrusion sensor registration (P=.005; 67.7%). None of the techniques showed higher probabilities of occlusal changes at a given time of day with respect to time-dependent changes. CONCLUSIONS: The study revealed that occlusion cannot be considered constant and that the topography and intensity of the contact points vary. Circadian occlusion variance can be assumed without preferring a specific time of the day. This differentiated view of occlusion as a changing system helps to clarify the challenge of dental restorations for both the patient and the practitioner.

Informational content of two-dimensional panoramic radiographs and lateral cephalometric radiographs with respect to the bone volume of intraoral donor regions considering CBCT imaging.

BACKGROUND: To test the hypothesis that cephalometric parameters in two-dimensional routine dental radiographs correlate with the bone volume of intraoral bone donor sites. METHODS: One-hundred and eight radiographs [36 panoramic radiographs (PRs), 36 lateral cephalometric radiographs (LCRs), and 36 cone-beam computed tomography scans (CBCT)] of 36 patients (all three imaging techniques applied according to the needs of treatment planning), were analyzed individually. Cephalometric parameters (PR and LCR) were correlated with the bone volume measurement in three-dimensional CBCT scans in three intraoral donor sites (chin, mandibular retromolar region, and zygomatic alveolar crest). RESULTS: The mean bone volumes measured for the chin were (3.10 ± 1.11 cm³ SD), the mandibular retromolar region (1.66 ± 0.54 cm³ SD), and the zygomatic alveolar crest (0.17 ± 0.04 cm³ SD). Cephalometric parameters were significantly correlated (all p-values < 0.05) with the bone volume in the chin and the mandibular retromolar region. The bone volume of the zygomatic alveolar crest exhibited no correlations (p > 0.05) with cephalometric parameters. However, it was significantly correlated (p < 0.01) with the mandibular retromolar bone volume. No gender-specific differences (p > 0.05) were observed concerning bone volumes in all bone harvesting regions. Nevertheless, the male population's interforaminal distance in the chin region was significantly higher (p = 0.001). CONCLUSIONS: PRs and LCRs can be used at the initial stage of peri-implant augmentation planning to deduce conclusions about the bone volume in different intraoral bone donor sites. It can help describe indications and justify additional diagnostic options, such as three-dimensional radiologic techniques.

Changes in Maximum Mandibular Mobility Due to Splint Therapy in Patients with Temporomandibular Disorders.

Splint therapy is widely used in the treatment of myofascial pain, but valid studies on the efficacy of this therapy are rare. The purpose of the present study was to investigate which qualifiable and quantifiable effects of splint therapy are detectable. For this purpose, 29 patients (21 women, mean age 44.6 ± 16 years) diagnosed with myofascial pain (RDC/TMD) were investigated in this prospective clinical trial (10/6/14An). Patients were treated with Michigan splints applied overnight for three months. Before (T1) and after three months of treatment (T2), patients were registered with an electronic ultrasound device with qualitative and quantitative evaluation of the registrations and a qualitative assessment of pain symptoms using a verbal analog scale. Significant differences were found between maximum mouth opening (MMP) (p < 0.001) and right condylar movement (CM) at MMP (p = 0.045). Qualitative assessment revealed that 24 of 29 patients experienced an improvement in pain symptoms, 17 of whom experienced complete remission. The results of the qualitative and quantitative analysis provide indications of the effectiveness of the splint therapy. In addition to quantitative measurements, the ultrasound facebow technique was also able to provide qualitative information.

Force delivery modification of removable thermoplastic appliances using Hilliard precision thermopliers for tipping an upper central incisor.

OBJECTIVES: To evaluate the force delivered by removable thermoplastic appliances (RTAs, aligners), altered with Hilliard precision thermopliers, on an upper central incisor to tip it in the palatal and vestibular directions. MATERIALS AND METHODS: A total of 10 aligners made from Ideal Clear® (polyethylene terephthalate glycol copolyester, PET-G) with a thickness of 1 mm were used in force analysis. Different-sized spot-thermoformed protuberances (bumps) were generated by activating the thermoplier (thin and thick) up to 30°, 60° and 90° in the centre of the palatal and vestibular surfaces of the aligner in 15° steps. The tipping (Fx) and intrusive (Fz) force components were measured on the isolated upper central incisor as part of a standardized resin model, with or without vertical loading by a weight equivalent. RESULTS: Thermoplier activation at 30°, 60° and 90° resulted in different bump heights. The analysis revealed significantly higher Fx and Fz values with increasing bump heights for every activation step in all cases (p < 0.0001, respectively). Overall, the values of the Fx force component were higher than those observed for Fz. Significant differences between the palatal and vestibular tipping procedures were found depending on the resulting force components when the thin thermoplier was used; in contrast, the thick thermoplier resulted in a larger dispersion of the force magnitudes. CONCLUSIONS: Aligners modified with Hilliard precision thermopliers showed altered biomechanical parameters. This approach could be an option for treatment modification. CLINICAL RELEVANCE: The instrumental examination provided informative results for daily practice, as activation, force dosage and different force values under chewing pressure can be estimated more precisely based on the determined force levels.

Combined quality of life and posttraumatic growth evaluation during follow-up care of patients suffering from oral squamous cell carcinoma.

Oral cancer therapy is associated with a loss in health-related quality of life (HRQOL) and can also lead to post-traumatic growth (PTG). The current study analyzed the relationship between HRQOL, PTG and influencing clinical factors after treatment. The coherent clinical data of 15 patients were retrospectively analyzed over a 1-year study period. HRQOL and PTG were studied using the University of Washington Quality of Life Version 4 (UW-QOL v4) and Posttraumatic Growth Inventory (PTGI) questionnaires. The results revealed that HRQOL was significantly decreased in a pre- to postoperative manner (P=0.011). Sex demonstrated a nearly significant effect on HRQOL (P=0.058). PTG was experienced the most after surgery, and continuously decreased over the 1-year study period. Patient age had a significant effect on PTG (P=0.040). A significant correlation was also established between HRQOL and PTG (P<0.05). HRQOL and PTG are important influencing factors during postoperative tumor follow-up care and should be simultaneously recorded to address individual patient needs and improve quality of treatment.