Factors associated with voice-related quality of life among patients with temporomandibular disorders.

BACKGROUND: Research would be important for obtaining a better understanding of voice complaints among patients with temporomandibular disorders (TMD). OBJECTIVE: The identification of predictors of voice disorders associated with TMD pain was made according to Diagnostic Criteria for TMD (DC/TMD) Axis I. METHODOLOGY: Functional limitations were measured using the Jaw Functional Limitation Scales for mastication (JFLS-M), jaw mobility (JFLS-JM), and verbal and emotional expression (JFLS-VEE). Patients also completed the Hospital Anxiety and Depression Scale (HADS). The primary outcome was social-emotional and physical functioning as indicated by scores on the Voice-Related Quality of Life (V-RQOL) questionnaire. Multiple linear regression was used to model the relationship between the domains on the V-RQOL questionnaire and scores on the HADS and JFLS after adjusting for age, gender, DC/TMD diagnosis, pain intensity, and time since pain onset. RESULTS: The HADS-D (B=-1.15; 95% CI, -1.718 to -0.587; p<.001) and JFLS-VEE (B=-0.22; 95% CI, -0.40 to -0.06; p=.008) were significant predictors of scores on the V-RQOL questionnaire. CONCLUSION: Higher scores on depression measures and limitations in verbal and emotional expression could exacerbate voice problems among TMD pain patients. Future research should promote multidisciplinary treatments for TMD pain-related voice disorders.

The Value of Surveillance Imaging of Oral Squamous Cell Carcinoma.

The evaluation of surveillance imaging of OSCC patients is a difficult task physicians have to face daily. Multiple patients experience a recurrence of this disease, which underlines the importance of regular patient monitoring programs. Our study analysed the value of surveillance imaging, such as computed tomography (CT) and nuclear magnetic resonance imaging (NMRI), as a patient monitoring programme and its effectiveness in achieving improvement in early recurrence detection. The study comprised 125 patients, out of which 56 (n = 56) showed radiological and 69 (n = 69) showed clinical and radiological conspicuous patterns in domestic follow-ups, respectively. The use of CT and NMRI showed a significant dependence on the histological result (p = 0.03). However, the different groups showed no significant dependence on the histological result (p = 0.96). The distribution of the histological biopsies, which were taken due to radiological changes, were prone to wrong positive diagnoses (false positives) in 71 percent. To conclude, imaging modalities should be chosen for each patient individually to reduce false positives, improve the early detection of recurrence, and increase the cure rate.

Rhinoresistometry as a Cost-Efficient and Time-Saving Alternative to Acoustic Rhinometry for Longitudinal Assessment of Nasal Patency in Orthognathic Surgery.

Rhinoresistometry (RRM) is implemented along with active anterior rhinomanometry (AAR) and can evaluate nasal dimensions [hydraulic diameter (HD)]. As acoustic rhinometry (AR) is time-consuming, the authors investigated if RRM can be an efficient alternative to AR in nasal dimension assessment in orthognathic surgery. In patients undergoing maxillary advancement and impaction (cases) and removal of maxillary cysts (controls), the authors evaluated RRM and AR, before and 1 year after surgery. Furthermore, the authors investigated the correlation of HD with Nasal Obstruction Symptom Evaluation score and volume by computed tomography and AAR. Lastly, the authors measured RMM reproducibility by the Bland-Altman agreement method in controls. In 14 cases, AR and RMM revealed a significant increase on both sides (all P < 0.011) and the right side, respectively (P = 0.028). The authors noted no changes in 14 controls. Hydraulic diameter correlated only with AAR (most P < 0.004). Acoustic rhinometry lasted ~4 minutes before or after decongestion. In controls, HD after surgery was as large (1.05 times larger) as before surgery (up to 39% error rates). Rhinoresistometry can reproducibly assess nasal dimension changes in orthognathic surgery in a way that is different from AR and correlates with nasal function. Rhinoresistometry can help clinicians avoid AR and save significant time, as well as financial and human resources.

Perioperative anticoagulation in head and neck free flap reconstructions: Experience of an anticoagulative scheme and its modification.

OBJECTIVES: Microvascular anastomoses in microvascular reconstructions induce rheological changes in the anastomosed vessels and are usually counteracted by anticoagulative medication. There is no regimen commonly agreed on. This study provides an easy to use anticoagulative regimen. PATIENTS AND METHODS: Consecutive cases of either anticoagulative regimen between 2013 and 2018 that underwent microvascular reconstruction in the head and neck area were included in this retrospective study, resulting in 400 cases in total. Two different anticoagulative regimens were applied to 200 patients in each group: (a) intraoperatively administered unfractionated 5000 I.U. high molecular weight heparin (HMWH) and postoperatively low molecular weight heparin (LMWH, Enoxaparin) 1 mg/kg/body weight postoperatively and (b) intraoperatively LMWH 0.5 mg/kg/body weight as well as 12 h later and 1 mg/kg/body weight postoperatively. RESULTS: The LMWH cohort showed fewer overall thromboembolic (8.5% vs. 11%; p = .40) and peripheral thrombotic events (1% vs. 3.5%; p = .18) and lung embolisms (3% vs. 4%; p = .59). The number of thromboses at the site of the anastomosis was equally distributed. In regard to flap-specific complications, LMWH was associated with a positive effect, in particular with respect to total flap losses (5% vs. 7%; p = .40) and wound-healing disorders (14.5% vs. 20%; p = .145). CONCLUSION: Findings indicate that intra- and postoperatively administered LMWH as the only anticoagulative medication seems reliable in our clinical routine of head and neck free flap reconstructions.

Factors associated with voice-related quality of life among patients with temporomandibular disorders

Abstract Research would be important for obtaining a better understanding of voice complaints among patients with temporomandibular disorders (TMD). Objective The identification of predictors of voice disorders associated with TMD pain was made according to Diagnostic Criteria for TMD (DC/TMD) Axis I. Methodology Functional limitations were measured using the Jaw Functional Limitation Scales for mastication (JFLS-M), jaw mobility (JFLS-JM), and verbal and emotional expression (JFLS-VEE). Patients also completed the Hospital Anxiety and Depression Scale (HADS). The primary outcome was social-emotional and physical functioning as indicated by scores on the Voice-Related Quality of Life (V-RQOL) questionnaire. Multiple linear regression was used to model the relationship between the domains on the V-RQOL questionnaire and scores on the HADS and JFLS after adjusting for age, gender, DC/TMD diagnosis, pain intensity, and time since pain onset. Results The HADS-D (B=-1.15; 95% CI, -1.718 to -0.587; p<.001) and JFLS-VEE (B=-0.22; 95% CI, -0.40 to -0.06; p=.008) were significant predictors of scores on the V-RQOL questionnaire. Conclusion Higher scores on depression measures and limitations in verbal and emotional expression could exacerbate voice problems among TMD pain patients. Future research should promote multidisciplinary treatments for TMD pain-related voice disorders.

Clinical Experience with Autofluorescence Guided Oral Squamous Cell Carcinoma Surgery.

In our study, the effect of the use of autofluorescence (Visually Enhanced Lesion Scope-VELscope) on increasing the success rate of surgical treatment in oral squamous carcinoma (OSCC) was investigated. Our hypothesis was tested on a group of 122 patients suffering from OSCC, randomized into a study and a control group enrolled in our study after meeting the inclusion criteria. The preoperative checkup via VELscope, accompanied by the marking of the range of a loss of fluorescence in the study group, was performed before the surgery. We developed a unique mucosal tattoo marking technique for this purpose. The histopathological results after surgical treatment, i.e., the margin status, were then compared. In the study group, we achieved pathological free margin (pFM) in 55 patients, pathological close margin (pCM) in 6 cases, and we encountered no cases of pathological positive margin (pPM) in the mucosal layer. In comparison, the control group results revealed pPM in 7 cases, pCM in 14 cases, and pFM in 40 of all cases in the mucosal layer. This study demonstrated that preoperative autofluorescence assessment of the mucosal surroundings of OSCC increased the ability to achieve pFM resection 4.8 times in terms of lateral margins.

Controversial Aspects of Diagnostics and Therapy of Idiopathic Condylar Resorption: An Analysis of Evidence- and Consensus-Based Recommendations Based on an Interdisciplinary Guideline Project.

Idiopathic condylar resorption (ICR), though a rare event, is associated with severe detrimental sequelae for the patient. To date, the etiology remains unknown, and treatment strategies are highly controversial. Therefore, the aim of this study is to present an analysis of the consensus- and evidence-based approach to ICR by a German interdisciplinary guideline project of the AWMF (Association of the Scientific Medical Societies in Germany). Following a systematic literature search, including 56 (out of an initial 97) publications, with a predominantly low level of evidence (LoE), two independent working groups (oral and maxillofacial surgery and interdisciplinary, respectively) voted on a draft comprising 25 recommendations in a standardized anonymized and blinded Delphi procedure. While the results of the votes were relatively homogeneous, the interdisciplinary phase required a significantly higher number of rounds (p < 0.001). Most of the controversial recommendations were related to initial imaging (with consensus on CT/CBCT as the current diagnostic standard for imaging), pharmacotherapy (no recommendation due to lack of evidence), discopexy (no recommendation possible due to low LoE) and timing of orthognathic surgery (with consensus on two-staged procedures after invasive TMJ surgery, except for single-stage procedures if combined with total joint reconstruction). Overall, the Delphi procedure resulted in an interdisciplinary guideline offering the best possible evidence- and consensus-based expertise to date in the diagnosis and treatment of ICR.

The long-term effect of maxillary advancement and impaction on subjective and objective nasal patency: A retrospective case-control study.

The aim of this study was to investigate the change of nasal patency after maxillary advancement and impaction (MAXADV + IMP) in subjects with skeletal class III malocclusion (cases) and after removal of maxillary cysts in close proximity to the nasal floor in subjects that served as controls. NOSE score, volume derived by computed tomography (VOL), and acoustic rhinometry and rhinomanometry were retrospectively evaluated, before and one year after surgery. The movement of specific landmarks was also measured. NOSE score did not change after surgery, neither in 17 cases (p = 0.10) nor in 17 controls (p = 0.14). In cases, VOLpostop (10088 ± 4200 mm3) was significantly higher than VOLpreop (7807 ± 3721 mm3; p = 0.036). Maxillary advancement and inferior displacement of the ventral maxilla were noted by the movement of incisive foramen in the coronal (3.9 ± 5.4; p = 0.011) and Frankfurt Horizontal plane (2.2 ± 2.0; p = 0.001), respectively. In controls, VOLpostop (9749 ± 3654 mm3) was also significantly higher than VOLpreop (8473 ± 2624 mm3; p = 0.050). Cross-sectional areas, nasal flow and nasal resistance changed significantly after surgery in cases (6/30 pairs; p < 0.018), but not in controls (all p > 0.066). MAXADV + IMP increased nasal patency, but did not change the feeling of nasal breathing. Physicians should proceed with caution when informing patients about improvement of nasal breathing after MAXADV + IMP.

Modeling the effect of bilateral sagittal split osteotomy on posterior, superior and medial space dimensions of the temporomandibular joint: a retrospective controlled cohort study.

BACKGROUND: To model the effect of isolated bilateral sagittal split osteotomy (BSSO) on changes in posterior (PSD), superior (SSD), and medial space dimensions (MSD) of the temporomandibular joint. METHODS: Using a retrospective cohort study design, pre- and postoperative (immediately after surgery; 1 year follow-up) cone-beam computed tomography measurements of 36 patients who had undergone BSSO for mandibular advancement were compared with a control group of 25 subjects from whom a mandibular odontogenic cyst was removed under general anesthesia. Generalized estimation equation (GEE) models were used to examine the independent effects of study group, preoperative condylar position, and time points on PSD, SSD, and MSD adjusting for covariates (age, sex, and mandibular advancement). RESULTS: No significant differences were found regarding changes in PSD (p = 0.144), SSD (p = 0.607), or MSD (p = 0.565) between the BSSO and control groups. However, the preoperative posterior condylar position showed significant effects on PSD (p < 0.001) and MSD (p = 0.043), while the preoperative central condylar position demonstrated a significant effect on PSD (p < 0.001). CONCLUSION: The data suggest that preoperative posterior condylar position is a significant effect modifier of PSD and MSD over time in this cohort.

Targeting Cell Cycle Facilitates E1A-Independent Adenoviral Replication.

DNA replication of E1-deleted first-generation adenoviruses (AdV) in cultured cancer cells has been reported repeatedly and it was suggested that certain cellular proteins could functionally compensate for E1A, leading to the expression of the early region 2 (E2)-encoded proteins and subsequently virus replication. Referring to this, the observation was named E1A-like activity. In this study, we investigated different cell cycle inhibitors with respect to their ability to increase viral DNA replication of dl70-3, an E1-deleted adenovirus. Our analyses of this issue revealed that in particular inhibition of cyclin-dependent kinases 4/6 (CDK4/6i) increased E1-independent adenovirus E2-expression and viral DNA replication. Detailed analysis of the E2-expression in dl70-3 infected cells by RT-qPCR showed that the increase in E2-expression originated from the E2-early promoter. Mutations of the two E2F-binding sites in the E2-early promoter (pE2early-LucM) caused a significant reduction in E2-early promoter activity in trans-activation assays. Accordingly, mutations of the E2F-binding sites in the E2-early promoter in a virus named dl70-3/E2Fm completely abolished CDK4/6i induced viral DNA replication. Thus, our data show that E2F-binding sites in the E2-early promoter are crucial for E1A independent adenoviral DNA replication of E1-deleted vectors in cancer cells. IMPORTANCE E1-deleted AdV vectors are considered replication deficient and are important tools for the study of virus biology, gene therapy, and large-scale vaccine development. However, deletion of the E1 genes does not completely abolish viral DNA replication in cancer cells. Here, we report, that the two E2F-binding sites in the adenoviral E2-early promoter contribute substantially to the so-called E1A-like activity in tumor cells. With this finding, on the one hand, the safety profile of viral vaccine vectors can be increased and, on the other hand, the oncolytic property for cancer therapy might be improved through targeted manipulation of the host cell.

The Oncolytic Adenovirus XVir-N-31 Joins Forces with CDK4/6 Inhibition Augmenting Innate and Adaptive Antitumor Immunity in Ewing Sarcoma.

PURPOSE: Ewing sarcoma (EwS) is a highly malignant pediatric tumor characterized by a non-T-cell-inflamed immune-evasive phenotype. When relapsed or metastasized, survival is poor, emphasizing the need for novel treatment strategies. Here, we analyze the novel combination approach using the YB-1-driven oncolytic adenovirus XVir-N-31 and CDK4/6 inhibition to augment EwS immunogenicity. EXPERIMENTAL DESIGN: In vitro, viral toxicity, replication, and immunogenicity were studied in several EwS cell lines. In vivo tumor xenograft models with transient humanization were applied to evaluate tumor control, viral replication, immunogenicity, and dynamics of innate as well as human T cells after treatment with XVir-N-31 combined with CDK4/6 inhibition. Furthermore, immunologic features of dendritic cell maturation and T-cell-stimulating capacities were assessed. RESULTS: The combination approach significantly increased viral replication and oncolysis in vitro, induced HLA-I upregulation, and IFNγ-induced protein 10 expression and enhanced maturation of monocytic dendritic cells with superior capacities to stimulate tumor antigen-specific T cells. These findings were confirmed in vivo showing tumor infiltration by (i) monocytes with antigen-presenting capacities and M1 macrophage marker genes, (ii) TReg suppression in spite of adenovirus infection, (iii) superior engraftment, and (iv) tumor infiltration by human T cells. Consequently, survival was improved over controls with signs of an abscopal effect after combination treatment. CONCLUSIONS: The joint forces of the YB-1-driven oncolytic adenovirus XVir-N-31 and CDK4/6 inhibition induce therapeutically relevant local and systemic antitumor effects. Innate as well as adaptive immunity against EwS is boosted in this preclinical setting, pointing toward high therapeutic potential in the clinic.

Chondrogenic differentiation of mouse CD105+ stem/progenitor cells on amino-group-functionalized biosilica-hydrogel scaffolds.

OBJECTIVES: Mesenchymal stem/progenitor cells (MSPCs) are critical for tissue regeneration. Moreover, the CD105 antigen identifies early MSPCs with increased chondrogenic differentiation ability. We hypothesized that amine-(NH2)-functionalized biosilica incorporating hydrogel scaffolds, seeded with mCoSPCs105+ would contribute to creating tissue-engineered scaffolds, capable of de novo cartilage synthesis. MATERIALS AND METHODS: Scaffolds were characterized by water uptake, lysozyme degradation, axial compression, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Differentiation stimulus of scaffold functionalization was evaluated using Alcian blue staining. Cartilage-forming abilities of mCoSPCs105+ were evaluated using Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. RESULTS: Biosilica particle incorporation into scaffolds resulted in increased water uptake capacity and compression force withstanding abilities. Amine-(NH2)-group functionalization of biosilica led to significantly increased stem cell differentiation potential, by Alcian blue staining, in the first 3 weeks. Scaffold attachment and viable cell proliferation were observed for 6 weeks under chondrogenic differentiation. Downregulation of Runx2, an increase of Col10a1, Ihh, and maintenance of Sox9, was seen under these culture conditions. mCoSPCs105+ gene expression pattern was defined by the significant upregulation of Col1a1, Col2a1, Prg4, and Agc-1 over 6 weeks of incubation compared to the unsorted control. Immunostaining of cell-seeded scaffolds revealed significantly higher secretion of proteins relevant to cartilage extracellular matrix. CONCLUSION: The preselecting of CD105+ phenotype in MSPCs may enhance tissue regeneration of fibrocartilage and biosilica nanoparticles may be a beneficial additive in tissue engineering of scaffolds.

Temporal Tendinitis in Craniomandibular Dysfunction (CMD) - Does it Really Exist? A Temporomandibular MRI Investigation.

OBJECTIVES: The aim of the study was to analyze the role of temporal muscle and particularly tendon pathology in patients suffering from craniomandibular dysfunction (CMD) using magnetic resonance imaging. MATERIALS AND METHODS: Retrospective analysis of MRI examinations was carried out with regard to temporal muscle fibrosis and fatty degeneration and particularly temporal tendon rupture, thickening, and degenerative signal alterations. Descriptive statistics and the Mann-Whitney U-test were used for statistical evaluation. RESULTS: Structural lesions of temporal muscle parenchyma were the absolute exception. PD hyperintensity, pronounced contrast enhancement, or peritendinous fluid collections along the temporal tendon were found only to a small extent, and a (partial) rupture occurred in only one case. The tendon diameter showed only slight variability. The Mann-Whitney U-test provided no results indicating a causal connection between degenerative joint or disc disease and temporal tendon pathology. CONCLUSION: A large sample of 128 magnetic resonance imaging examinations provided no evidence of a major role of temporal tendinitis in clinical CMD syndrome. KEY POINTS: · Retrospective analysis of temporal tendon in CMD patients.. · Abnormal structural findings along the tendon seen only rarely.. · Obviously no crucial role of temporal tendon lesions in CMD syndrome.. CITATION FORMAT: · Stimmer H, Grill F, Waschulzik B et al. Temporal Tendinitis in Craniomandibular Dysfunction (CMD) - Does it Really Exist? A Temporomandibular MRI Investigation. Fortschr Röntgenstr 2022; 194: 1242 - 1249.

Controversial Aspects of Diagnostics and Therapy of Arthritis of the Temporomandibular Joint in Rheumatoid and Juvenile Idiopathic Arthritis-An Analysis of Evidence- and Consensus-Based Recommendations Based on an Interdisciplinary Guideline Project.

Introduction: Due to potentially severe sequelae (impaired growth, condylar resorption, and ankylosis) early diagnosis of chronic rheumatic arthritis of the temporomandibular joint (TMJ) and timely onset of therapy are essential. Aim: Owing to very limited evidence the aim of the study was to identify and discuss controversial topics in the guideline development to promote further focused research. Methods: Through a systematic literature search, 394 out of 3771 publications were included in a German interdisciplinary guideline draft. Two workgroups (1: oral and maxillofacial surgery, 2: interdisciplinary) voted on 77 recommendations/statements, in 2 independent anonymized and blinded consensus phases (Delphi process). Results: The voting results were relatively homogenous, except for a greater proportion of abstentions amongst the interdisciplinary group (p < 0.001). Eighty-four percent of recommendations/statements were approved in the first round, 89% with strong consensus. Fourteen recommendations/statements (18.2%) required a prolonged consensus phase and further discussion. Discussion: Contrast-enhanced MRI was confirmed as the method of choice for the diagnosis of TMJ arthritis. Intraarticular corticosteroid injection is to be limited to therapy-refractory cases and single injection only. In adults, alloplastic joint replacement is preferable to autologous replacement. In children/adolescents, autologous reconstruction may be performed lacking viable alternatives. Alloplastic options are currently still considered experimental.

Does molar distalization by the Beneslider have skeletal and dental impacts? A prospective 3D analysis.

OBJECTIVE: The study aimed to clarify (1) the effect of the Beneslider distalization appliance on maxillary molars (M1+2), (2) the type of tooth movement, and (3) changes in skeletal parameters. STUDY DESIGN: Dental distalization paths and transversal changes were measured according to the distance of the pterygoid vertical as well as on the virtualized 3D plaster model. RESULTS: Distalization of the second premolar (P2; T1 - T2) was 2.51 mm (±1.81 mm; P < .001) combined with a distal tipping of 6.50° (±5.09°; P < .001), whereas for M1 a distalization of 3.49 mm (±1.10 mm) occurred with negligible tipping (0.73° ± 5.04°). No significant differences (T1 - T2) on sagittal and vertical skeletal variables were found within or between G1+2. In contrast, a significant increase in N-Sp' in G2 and in Sp'-Gn in G1+2 with consecutive Hasund index reduction was shown. Comparing T1 and T2, the device had an effect on the transversal development. CONCLUSION: The Beneslider distalization appliance causes an effective distalization of M1+2, with slight second premolar tipping. No modification of skeletal parameters was recorded, but a relevant effect on Hasund index and the transverse was found.

Factors Associated With Postoperative Delirium in Patients Undergoing Complex Head and Neck Flap Surgery.

PURPOSE: Postoperative delirium (PD) is a common and severe complication, following extensive surgery and prolonged stays in intensive care units (ICU). The study aimed to estimate the frequency of and identify risk factors for PD in a unified sample of head and neck surgery patients. METHODS: The investigators implemented a retrospective cohort study composing of patients undergoing free flap reconstructive surgery over 1 year. The predictor variables were identified as 146 general and periprocedural parameters. The primary outcome variable was PD (+ or -). Descriptive and bivariate statistics were performed to identify existing correlations between the predictive factors and PD and the P-value was set at .05. A logistic regression model (LRM) was created to adjust for possible confounding factors and reveal possible independent prognostic factors for the onset of PD. RESULTS: Hundred patients (group 1, 18 with PD+, group 2, 82 without PD) undergoing microvascular free flap (65 males, 35 females, mean age = 65 [range 18 to 84 years]) surgery were recruited. The investigators identified 15 variables that were statistically associated with PD. In the LRM, after adjusting for age, diabetes status, and preoperative TSH, free fibula transplants (FT) as type of surgery was associated with an increased risk for PD (FT, Odds Ratio (OR) 6.3 (1.6 to 25.7, P = .01). CONCLUSION: The investigators identified 15 variables associated with an increased risk of developing PD, one of which had a statistically significant association after adjusting for other variables in a LRM. Future research efforts should be devoted to assessing the use of these variables for predicting PD further. Since the use of FT showed to be an independent prognostic parameter for the development of PD in this study, patients receiving FT should get special attention in the first days after surgery to prevent PD and associated complications such as increased mortality and prolonged hospital stays.

The ESTMJS (European Society of Temporomandibular Joint Surgeons) Consensus and Evidence-Based Recommendations on Management of Condylar Dislocation.

Although condylar dislocation is not uncommon, terminology, diagnostics, and treatment concepts vary considerably worldwide. This study aims to present a consensus recommendation based on systematically reviewed literature and approved by the European Society of TMJ Surgeons (ESTMJS). Based on the template of the evidence-based German guideline (register # 007-063) the ESTMJS members voted on 30 draft recommendations regarding terminology, diagnostics, and treatment initially via a blinded modified Delphi procedure. After unblinding, a discussion and voting followed, using a structured consensus process in 2019. An independent moderator documented and evaluated voting results and alterations from the original draft. Although the results of the preliminary voting were very heterogenous and differed significantly from the German S3 guideline (p < 0.0005), a strong consensus was achieved in the final voting on terminology, diagnostics, and treatment. In this voting, multiple alterations, including adding and discarding recommendations, led to 24 final recommendations on assessment and management of TMJ dislocation. To our knowledge, the ESTMJS condylar dislocation recommendations are the first both evidence and consensus-based international recommendations in the field of TMJ surgery. We recommend they form the basis for clinical practice guidelines for the management of dislocations of the mandibular condyle.

Panoramic prediction equations to estimate implant- to-mandibular canal dimensions in the mandibular posterior region: implications for dental implant treatment.

BACKGROUND: To develop and cross-validate site-specific panoramic radiography (PAN) analysis prediction equations of implant-to-mandibular canal dimensions (IMCD) in mandibular regions posterior to the mental foramen, and to help determine in which instances CBCT technology will be a justified adjunct in clinical practice. METHODS: IMCD by PAN (Pan-D) from implant site-specific regions (first premolar, second premolar, first molar, and second molar sites) were collected from 40- to 70-year-old adolescents. They were randomly assigned to validation (n = 144) and cross-validation (n = 148) groups. The cone-beam computed tomography (CBCT) technique was used as the criterion method for the estimation of IMCD (CBCT-D). The PAN analysis equations were developed using stepwise multiple regression analysis and cross-validated using the Bland-Altman approach. RESULTS: There was a significant relationship between PAN-D and CBCT-D for both validation (R2 = 57.8 %; p < .001) and cross-validation groups (R2 = 52.5 %; p < .001). Root means-squared error (RMSE) and pure error (PE) were highest for the first molar (RMSE = 1.116 mm, PE = 1.01 mm) and the second molar region (RMSE = 1.162 mm, PE = 1.11 mm). CONCLUSIONS: PAN-D has the potential to be developed as an indirect measure of IMCD. However, the findings suggest to exclude scoring of the first and second molars when assessing IMCD via PAN. Use of CBCT may be justified for all IMCD estimations in the first and second molars regions. TRIAL REGISTRATION: This study has been registered and approved by the Ethics Committee of the Martin-Luther University, Halle, Germany (2020-034).