Diagnostic accuracy comparing OPT and CBCT in the detection of non-vital bone changes before tooth extractions in patients with antiresorptive intake.

OBJECTIVES: To compare the diagnostic accuracy in detecting early non-vital bone changes between orthopantomography (OPT) and cone-beam computed tomography (CBCT) in correlation with histopathological findings before tooth extractions in patients with antiresorptive (AR) intake. SUBJECTS: Patients with an indication tooth extraction who had received OPT and CBCT preoperatively while or after undergoing AR treatment were prospectively enrolled over a 24-month period in the progesterone in spontaneous miscarriage (PRISM) trial. Imaging studies were randomly analyzed by three examiners for early non-vital bone changes using specific predefined characteristics and a 5-level scale (1 definite absence of criteria to 5 definite presence of criteria). Sensitivity and specificity values were calculated in correlation with the histopathologically evaluated bone samples at the time point of tooth extraction. RESULTS: One hundred thirty patients with 237 treated extraction sites met the inclusion criteria. For all images evaluated by all examiners, CBCT (430/492; 87.4%; receiver operating characteristic [ROC]: area under the curve [AUC] = 0.88; p < 0.001) was more likely to detect histopathologically confirmed non-vital bone than the OPT (132/492; 26.8%; ROC: AUC = 0.562; p = 0.115). CONCLUSIONS: In the detection of non-vital bone changes, CBCT is superior to OPT in both sensitivity and specificity. Specific imaging characteristics allow for the prediction of early non-vital bone changes already at the time before tooth extractions.

Infants With Trigonocephaly Treated With Fronto-Orbital Remodelling and Endocortical Positioning of Resorbable Plates-A Retrospective Cohort Study Including 101 Patients.

PURPOSE: Fronto-orbital remodeling is the gold standard for surgical treatment of metopic synostosis in many craniofacial centers. For fixation, resorbable materials are widely used. Because of swelling during resorption, the positioning of the plates can be relevant. Therefore, the goal of this study was to investigate whether there are limitations to endocortical positioning of resorbable plates. METHODS: In this retrospective study, all patients with metopic craniosynostosis resulting in trigonocephaly, who were treated with a standardized fronto-orbital remodeling and endocortical positioning of resorbable plates, between February 2012 and December 2019 were included. The endpoint of this study was the postoperative complications that can be attributed to the material used. RESULTS: A total of 101 patients, who were treated at our unit, could be included with a male predominance, 81 (80.2%) boys versus 20 (19.8%) girls. Surgery was performed at a median age of 9 months (±2.56). No complications were seen related to resorbable plates. All patients of our study population were categorized as Whitaker classification I and II. CONCLUSION: This study shows that the risk level in using endocortical resorbable plates positioned on the inner surface of the bone is low. From an aesthetic point of view, we could not detect any disadvantage.

Comparing the Influence of Surgical and Conservative Therapy on Quality of Life in Patients with Early-Stage Medication-Related Osteonecrosis of the Jaw-A Prospective Longitudinal Study.

Background and Objectives: The purpose of this study was to evaluate the impact of surgical and conservative, non-surgical treatment on general health-related (QoL) and oral health-related quality of life (OHRQoL) in patients suffering from AAOMS stage I MRONJ. Materials and Methods: In the course of this prospective clinical study, QoL and OHRQoL using QLQ-C30 and QHIP G14 questionnaire were longitudinally assessed in N = 174 prospectively enrolled patients with indication of treatment of MRONJ stage I over a period of 12 months. Patients received conservative or surgical treatment. The measurement time points were preoperatively (T0), 12 weeks (T1), 6 months (T2) and 1 year after operation (T3). Results: For OHRQoL, no significant (p > 0.05) differences were found between both treatment groups for all timepoints (T0-T3). In the surgical treatment group, OHIP scores of T1, T2 and T3 were significantly lower than baseline measures (T0) (T0-T1 (2.99, p = 0.024), T0-T2 (5.20, p < 0.001), T0-T3 (7.44, p < 0.001)). For conservative treatment group OHIP, scores of T2 and T3 were significantly lower than baseline measures (T0) (T0-T2 (9.09, p = 0.013), T0-T3 (12.79, p < 0.001)). There was no statistically significant effect of time on QLQ-C30 scores in both groups (surgical treatment: F(3, 174) = 1.542, p < 0.205, partial η2 = 0.026; conservative treatment: F(3, 30) = 0.528, p = 0.667, partial η2 = 0.050). QLQ-C30 scores turned out to be significantly lower in the non-surgical group at T1 (p = 0.036) and T3 (p = 0.047) compared to the surgical treatment group. Conclusions: Surgical and conservative treatment of MRONJ stage I significantly improves patients' OHRQoL. Surgical treatment is superior to conservative treatment of MRONJ stage I regarding general QoL. Therefore, surgical treatment of MRONJ stage I should not be omitted for QoL reasons.

Neuralgia-inducing cavitational osteonecrosis - A systematic review.

OBJECTIVE: To assess the aetiologic factors, proposed diagnostic means and treatment strategies for neuralgia-inducing cavitational osteonecrosis. METHODS: A search of the literature published up to June 2020 was conducted using Medline, the Cochrane Library, PsycINFO, CINAHL and Web of Science. The scientific quality of the evidence was rated according to NIH Quality Assessment Tools. RESULTS: 4,051 articles were found, 59 were reviewed in full text, and 29 studies were included. With the exception of hereditary coagulopathies, which were identified as potential risk factors in five studies, suggestions concerning the aetiology varied widely. No gold standard diagnostic mean could be identified. Treatment was most often performed by surgical curettage of the affected bone. Surgical treatment outcomes were equally varied: significant facial pain remission was reported in 66%-100% for periods varying between 2 months to 18 years, whereas no or little relief and recurrences were reported in up to ⅓ of cases. All studies were observational in their design. All investigations were rated as poor quality because of high risk of bias and non-transparent reporting. CONCLUSIONS: Evidence concerning the aetiology, diagnosis and treatment of NICO is poor. Prospective diagnostic and therapeutic studies are needed before the usefulness of invasive therapeutic procedures can be evaluated.

Orthodontic shear bond strength and ultimate load tests of CAD/CAM produced artificial teeth.

OBJECTIVES: To investigate whether artificial CAD/CAM processed (computer-aided design/manufacturing) teeth could be a feasible option for the production of dental in vitro models for biomechanical testing. MATERIAL AND METHODS: Disks (n = 10 per group) made from two different CAD/CAM-materials, one fiber-reinforced composite (FRC; Trinia, Bicon) and one polymethylmethacrylate-based resin (PMMA; Telio CAD, Ivoclar Vivadent), as well as bovine teeth (n = 10), were tested for their shear bond strength (SBS) and scored according to the adhesive remnant index (ARI). In addition, CAD/CAM-manufactured lower incisor teeth were tested for their ultimate load (Fu). RESULTS: With regard to SBS, both PMMA (17.4 ± 2.2 MPa) and FRC (18.0 ± 2.4 MPa) disks showed no significant difference (p = 0.968) compared to bovine disks (18.0 ± 5.4 MPa). However, the samples differed with regard to their failure mode (PMMA: ARI 4, delamination failure; FRC: ARI 0 and bovine: ARI 1.6, both adhesive failure). With regard to Fu, FRC-based teeth could withstand significantly higher loads (708 ± 126 N) than PMMA-based teeth (345 ± 109 N) (p < 0.01). CONCLUSION: Unlike PMMA-based teeth, teeth made from FRC showed sufficiently high fracture resistance and comparable SBS. Thus, FRC teeth could be a promising alternative for the production of dental in vitro models for orthodontic testing. CLINICAL RELEVANCE: CAD/CAM-processed teeth made from FRC enable the use of standardized geometry and constant material properties. Using FRC teeth in dental in vitro studies has therefore the potential to identify differences between various treatment options with rather small sample sizes, while remaining close to the clinical situation.

Wound closure and alveoplasty after preventive tooth extractions in patients with antiresorptive intake-A randomized pilot trial.

OBJECTIVES: To compare success rates between the sub-periosteal prepared (SPP) muco-periosteal flap and the epi-periosteal prepared (EPP) mucosa flap and the feasibility of alveoplasty after surgical tooth extractions in patients undergoing/after antiresorptive treatment. SUBJECTS: Patients with an indication for preventive tooth extraction undergoing/after antiresorptive treatment were enrolled over a 24-month period in a parallel-group randomized clinical pilot trial and randomly assigned for primary wound closure to either the SPP or the EPP group. The primary outcome was treatment failure 8 weeks after surgery. To assess the feasibility of alveoplasty, necrotic bone changes at the time point of tooth extraction were evaluated. RESULTS: One hundred and sixty patients were randomized to the SSP (n = 82) or the EPP (n = 78) group. One hundred and fifty-seven patients met the primary endpoint 8 weeks after surgery with five treatment failures for the SPP group (6.3%) and 18 (23.4%) for the EPP group (p = .004). A significant relationship (p < .0001) was observed between symptomatic teeth and non-vital bone found in 54.8% of all biopsies. CONCLUSIONS: The strong superiority of the muco-periosteal flap as primary wound closure revealed the feasibility and effectiveness of the study. The large number of necrotic biopsies emphasizes the importance of alveoplasty as a preventive measure.

Impact of Salvage Surgery on Health-Related Quality of Life in Oral Squamous Cell Carcinoma: A Prospective Multi-Center Study.

BACKGROUND: Patients with recurrent oral squamous cell carcinoma (OSCC) have limited treatment options. Salvage surgery offers potential curative therapy. The need for extensive ablative surgery together with microvascular reconstruction implies invasive and painful treatment with questionable functional outcome. To address the impact of salvage surgery on the health-related quality of life (HRQoL) of patients suffering from recurrent OSCC, a multi-center prospective analysis was initiated. MATERIAL AND METHODS: Patients with recurrent OSCC from 2015 to 2022 at two German cancer centers were included. Interdisciplinary tumor board decisions determined surgery as the only curative treatment modality. HRQoL, was assessed via a EORTC questionnaire (European Organization for Research and Treatment of Cancer-EORTC: QLQ-C30 and QLQ-H&N35) in dependence of the recurrent tumor stage. Patients completed the questionnaires once before surgery (baseline) and then every 3 months during follow-up or up to the end of treatment. RESULTS: In total, 55 patients were included. The mean follow-up period was 26.7 ± 19.3 months. Global health status showed superior mean scores after 12 months (60.83 ± 22.58) compared to baseline (53.33 ± 26.41) in stage 1 and 2 recurrent tumors. In advanced recurrent tumors' mean scores for global health showed only minor positive differences after 12 months (55.13 ± 22.7) compared to baseline (53.2 ± 25.58). In terms of the mouth pain, mean scores were lower after salvage surgery in small recurrent tumors after 12 months (20.37 ± 17.73) compared to baseline (41.67 ± 33.07; Wilcoxon two-sample signed-rank test p = 0.028). In advanced recurrent tumors, a significant reduction in mean scores was detected 3 months after salvage surgery (29.7 ± 22.94) compared to baseline (47.76 ± 25.77; Wilcoxon two-sample signed-rank test p = 0.003). Up to 12 months, swallowing function was evaluated inferior compared to baseline independent of tumor stage (Mean score recurrent stage I/II: 12-months 48.15 ± 27.57, baseline 28.7 ± 22.87; stage III/IV: 12-months 49.36.42 ± 27.53; baseline 30.13 ± 26.25). CONCLUSION: Improved HRQoL could be obtained in advanced recurrent OSCC after salvage surgery despite reduced swallowing function. In small recurrent tumors, overall, HRQoL was superior to baseline. Salvage surgery positively affected pain burden. For advanced recurrent tumors, important pain relieve could be observed as soon as 3 months after surgery.

In vivo assessment of artefacts in MRI images caused by conventional twistflex and various fixed orthodontic CAD/CAM retainers.

PURPOSE: To assess magnetic resonance imaging (MRI) artefacts caused by different computer-aided design/computer-aided manufacturing (CAD/CAM) retainers in comparison with conventional hand bent stainless steel twistflex retainers in vivo. MATERIALS AND METHODS: MRI scans (3 Tesla) were performed on a male volunteer with different CAD/CAM retainers (cobalt-chromium, CoCr; nickel-titanium, NiTi; grade 5 titanium, Ti5) and twistflex retainers inserted. A total of 126 landmarks inside and outside the retainer area (RA; from canine to canine) were evaluated by two blinded radiologists using an established five-point visibility scoring (1: excellent, 2: good, 3: moderate, 4: poor, 5: not visible). Friedman and two-tailed Wilcoxon tests were used for statistical analysis (significance level: p < 0.05). RESULTS: Twistflex retainers had the strongest impact on the visibility of all landmarks inside (4.0 ± 1.5) and outside the RA (1.7 ± 1.2). In contrast, artefacts caused by CAD/CAM retainers were limited to the dental area inside the RA (CoCr: 2.2 ± 1.2) or did not impair MRI-based diagnostics in a clinically relevant way (NiTi: 1.0 ± 0.1; Ti5: 1.4 ± 0.6). CONCLUSION: The present study on a single test person demonstrates that conventional stainless steel twistflex retainers can severely impair the diagnostic value in head/neck and dental MRI. By contrast, CoCr CAD/CAM retainers can cause artefacts which only slightly impair dental MRI but not head/neck MRI, whereas NiTi and Ti5 CAD/CAM might be fully compatible with both head/neck and dental MRI.

Comparison of Different Antibiotic Regimes for Preventive Tooth Extractions in Patients with Antiresorptive Intake-A Retrospective Cohort Study.

In the present study, the impacts on success rates between three different antibiotic regimes in patients receiving preventive tooth extraction during/after antiresorptive treatment were compared. For the retrospective analysis, we enrolled patients who had undergone tooth extraction from 2009 to 2019 according to the specified preventive conditions under antiresorptive therapy. Three antibiotic regimens were distinguished: (Group 1) intravenous for 7 days, (Group 2) oral for 14 days, and (Group 3) oral for 7 days of application. The primary endpoint was the occurrence of medication-related osteonecrosis of the jaw at 12 weeks after surgery. A total of 760 patients and 1143 extraction regions were evaluated (Group 1 n = 719; Group 2 n = 126; Group 3 n = 298). The primary endpoint showed no significant difference in the development of medication-related osteonecrosis of the jaw between the groups studied (Group 1 n = 50/669 (7%); Group 2 n = 9/117 (7%); Group 3 n = 17/281 (6%); p = 0.746). Overall, the success rate was 93% after intervention when preventive measures were followed. With the same success rate, a reduced, oral administration of antibiotics seems to be sufficient regarding the possible spectrum of side effects, the development of resistance and the health economic point of view.

Osteoradionecrosis of the Jaw-Comparison between Bone and Soft Tissue Injury and Their Influence on Surgical Outcomes-A Retrospective Cohort Study.

Surgical therapy of osteoradionecrosis of the jaw (ORN) is challenging and requires treatment of the affected hard and soft tissue. To understand how tissue injury after irradiation influences surgical outcomes, the objective of this study was to find out whether (a) bone-related, (b) soft tissue-related, and (c) treatment-related parameters influence the surgical success of patients with ORN. A total of 175 patients (324 lesions) were included in this retrospective, single-center study. All patients were diagnosed with ORN and underwent surgical therapy. The primary outcome was complete soft tissue recovery (mucosa/skin) and the absence of symptoms 3 months after surgery. At the time of follow-up, 58% of patients (189 of 324 lesions) had intact intraoral or extraoral soft tissue. The extent of bone destruction had no effect on treatment success, whereas soft tissue injury due to fibrosis (OR: 0.344; CI 0.142-0.834; p = 0.01818) and xerostomia (OR: 0.163; CI 0.064-0.419; p = 0.00016) increased the probability of treatment failure. Soft tissue reconstruction with a microvascular graft improved therapeutic success compared to local wound closure (OR: 2.998; CI 1.371-6.555; p = 0.006). Thus, for the treatment of ORN, it is extremely important to pay attention not only to the extent of bone destruction but especially to soft tissue defects. Because the extent of soft tissue injury is a predictor for therapeutic success, it should influence the choice of surgical treatment.

A critical assessment of the medication-related osteonecrosis of the jaw classification in stage I patients: a retrospective analysis.

OBJECTIVES: It is unclear whether the extent of intraoral mucosa defects in patients with medication-related osteonecrosis of the jaw indicates disease severity. Therefore, this study investigated whether mucosal lesions correlate with the true extent of osseous defects in stage I patients. MATERIALS AND METHODS: Retrospectively, all patients with stage I medication-related osteonecrosis of the jaw who underwent surgical treatment between April 2018 and April 2019 were enrolled. Preoperatively, the extent of their mucosal lesions was measured in clinical evaluations, and patients were assigned to either the visible or the probeable bone group. Intraoperatively, the extent of necrosis was measured manually and with fluorescence. RESULTS: Fifty-five patients (36 female, 19 male) with 86 lesions (46 visible bone, 40 probeable bone) were enrolled. Intraoperatively, the necrotic le-sions were significantly larger (P<0.001) than the preoperative mucosal lesions in both groups. A significant (P<0.05) but very weak (R2<0.2) relation-ship was noted between the extent of the mucosal lesions and the necrotic bone area. CONCLUSION: Preoperative mucosal defects (visible or probeable) in patients with medication-related osteonecrosis of the jaw do not indicate the extent of bone necrosis or disease severity.

Influence of Preventive Tooth Extractions on Quality of Life in Patients with Antiresorptive Intake-A Prospective Longitudinal Study.

BACKGROUND: To find out whether preventive tooth extractions in patients on antiresorptive therapy have a direct impact on the patients' overall quality of life (QoL); Methods: QoL using the five-level version of the EuroQol Group's EQ-5D instrument (EQ-5D-5L) was longitudinally assessed in N = 114 prospectively enrolled patients with indication of preventive tooth extraction over a period of 12 months. Patients were stratified as high-risk (malignant disease with bone metastasis or multiple myeloma, with monthly high-dose antiresorptive therapy delivered intravenously [bisphosphonate] or subcutaneously [denosumab]) and low-risk/osteoporosis patients (weekly low-dose antiresorptive therapy administered orally [bisphosphonate] or half-yearly subcutaneously [denosumab]). The measurement time points were 4 weeks preoperatively (T0), 2 months (T1) and 1 year postoperatively (T2), respectively. RESULTS: EQ-5D-5L index scores fell in a range from -0.21 to 1.00 in the low-risk group to 0.15 to 1.00 in the high-risk group. The t-test comparing the baseline index scores of both groups showed EQ-5D-5L index score in the low-risk group (0.708 ± 0.292) to be significantly smaller (p = 0.037) than in the high-risk group (0.807 ± 0.19). ANCOVA showed no significant differences in EQ-5D-5L index scores between the groups at T1 and T2. CONCLUSIONS: Preventive tooth extractions in patients undergoing antiresorptive treatment have no negative effect on QoL. Therefore, if indicated, preventive tooth extraction should not be omitted. Patient-oriented outcome measures are important to obtain a good risk-benefit balance for patient-specific treatment.

Head motion during cone-beam computed tomography: Analysis of frequency and influence on image quality.

PURPOSE: Image artifacts caused by patient motion cause problems in cone-beam computed tomography (CBCT) because they lead to distortion of the 3-dimensional reconstruction. This prospective study was performed to quantify patient movement during CBCT acquisition and its influence on image quality. MATERIALS AND METHODS: In total, 412 patients receiving CBCT imaging were equipped with a wireless head sensor system that detected inertial, gyroscopic, and magnetometric movements with 6 dimensions of freedom. The type and amplitude of movements during CBCT acquisition were evaluated and image quality was rated in 7 different anatomical regions of interest. For continuous variables, significance was calculated using the Student t-test. A linear regression model was applied to identify associations of the type and extent of motion with image quality scores. Kappa statistics were used to assess intra- and inter-rater agreement. Chi-square testing was used to analyze the impact of age and sex on head movement. RESULTS: All CBCT images were acquired in a 10-month period. In 24% of the investigations, movement was recorded (acceleration: >0.10 [m/s2]; angular velocity: >0.018 [°/s]). In all examined regions of interest, head motion during CBCT acquisition resulted in significant impairment of image quality (P<0.001). Movement in the horizontal and vertical axes was most relevant for image quality (R2>0.7). CONCLUSION: Relevant head motions during CBCT imaging were frequently detected, leading to image quality loss and potentially impairing diagnosis and therapy planning. The presented data illustrate the need for digital correction algorithms and hardware to minimize motion artefacts in CBCT imaging.

Accuracy of laser-melted patient-specific implants in genioplasty - A three-dimensional retrospective study.

PURPOSE: To assess the accuracy of laser-melted patient-specific implants (PSI) with regard to a preoperative virtual treatment plan for genioplasty based on a new analysis method without the use of landmarks. MATERIALS AND METHODS: A retrospective evaluation of a cohort of Class II and Class III patients who had undergone virtually planned orthognathic surgery (including genioplasty) was carried out. The preoperative virtual treatment plan and the postoperative outcome were fused to calculate the translational and rotational discrepancies between the 3D planning and the actual surgical outcome. RESULTS: The accuracy of left/right positioning was 0.25 ± 0.28 mm (p < 0.001), that of anterior/posterior positioning was 0.70 ± 0.64 mm (p < 0.001), and that of up/down-positioning was 0.45 ± 0.38 mm (p < 0.001). The rotational discrepancies were less than 2 deg. The virtually planned and postoperative positions of the chin differed significantly from each other (p < 0.001 for all rotational and translational discrepanices). CONCLUSION: The findings demonstrate that PSIs can transfer the planned virtual genioplasty into the operation theatre with small but significant deviations. However, since no conclusions can be drawn from the results regarding surgical success in terms of shaping the soft tissue profile as well as the esthetic result, no superiority of PSI over traditional plate osteosynthesis can be demonstrated.

Midface correction in patients with Crouzon syndrome is Le Fort III distraction osteogenesis with a rigid external distraction device the gold standard?

INTRODUCTION: Le Fort III distraction osteogenesis with a rigid external distraction device is a powerful procedure to correct both exorbitism and impaired airways in faciocraniosynostosis. The aim of this study was to investigate treatment effect, perioperative parameters and volumetric outcomes after Le Fort III distraction osteogenesis in patients with Crouzon syndrome in a retrospective study design and to explore potential strengths and weaknesses of this procedure. MATERIALS AND METHODS: From June 2013 to February 2015, a total of nine children with Crouzon syndrome underwent Le Fort III distraction osteogenesis with a rigid external distraction device (RED device, KLS Martin, Tuttlingen, Germany). Along with perioperative parameters, sleep study reports, traditional cephalometric analysis, three-dimensional imaging and photographs were evaluated for severity of disease and therapeutic effect and structural and functional changes of the upper airway preoperatively, after device removal and one year postoperatively. RESULTS: Surgery for Le Fort III distraction was performed at a median age of 12.5 years (SD 2.5 months) with an average weight of 43.0 kg (SD 12.9 kg). Mean estimated blood loss was 535.7 ml (SD 128.1 ml), not requiring any red blood cell transfusions. Mean duration of surgery was 240 min (SD 30.6min), average hospital stay eight days (SD 0.5 days) with a planned median ICU stay of 1.7 days (SD 0.4 days) for all patients. There were a total of five minor complications. Exorbitism and Angle class III malocclusions were corrected in all patients. No patient showed velopharyngeal problems postoperatively. The average amount of distraction was 18.4 mm (14-26 mm). Average length of the distraction period was 18.3 days (SD 0.4 days), with a total distraction plus consolidation time of three months (SD 0.25 months). In two patients, vector correction was performed during distraction. A counterclockwise movement despite vector correction, clinically resulting in an open bite, was observed in one of these two patients. Eight of the nine patients showed a frontal overbite at the end of the distraction period. Cephalometric analysis revealed a significant increase of Sella-Nasion-Point A angle (SNA) from 76.0° (+/- 2.9; T1) to 86.0° (+/- 3.4; T2) (p = 0.006) and growth-related point A-Nasion-point B angle (ANB) from -4.8° (+/-3.7) to 5.7° (+/-4.8) (p = 0.001) from preoperatively to device removal and stable results one year postoperatively. Upper airway structure and respiratory function were improved clinically after the Le Fort III DO treatment in all cases with an average posterior airway space increase from 3199 mm3 (+/- 229.6 mm3) to 8917,7 ml (+/-415.1 mm3) (T1 to T2). Surgical outcome was judged good to excellent both by patients and families and the craniofacial team. CONCLUSION: Le Fort III DO with a rigid external distraction device in patients with Crouzon syndrome is a powerful and reliable surgical procedure that reliably produces a more significant change of appearance than most other single procedures routinely performed by craniofacial surgeons. It effectively treated sleep apnea in the affected patients. In our collective, the maxilla remained stable after advancement without any relapse, but there was no subsequent anterior growth on one year follow-up. Careful vector planning was able to avoid frontal open bite in eight patients. Complication rates were acceptably low and patients' functional and esthetic outcome was high.

Is the conservative non-surgical management of medication-related osteonecrosis of the jaw an appropriate treatment option for early stages? A long-term single-center cohort study.

PURPOSE: No consensus has been reached regarding the best treatment option for early-stage lesions in medication-related osteonecrosis of the jaw (MRONJ). The purpose of the present study was to evaluate the long-time outcomes of conservative non-surgical management in stage I patients with underlying malignant disease. MATERIALS AND METHODS: We designed and implemented a retrospective cohort study and enrolled, between 2008 and 2018, a sample of patients with the indication for non-surgical conservative treatment stage I lesions. The primary outcome variable was treatment success defined as mucosal integrity without signs of infection. Secondary outcomes were: (i) worsening stage, (ii) necessity for surgical intervention over time, and (iii) discontinuation of antiresorptive therapy. RESULTS: The sample included 75 patients with 92 lesions. Eight lesions showed full mucosal coverage, whereas 84 continued with exposed jaw bone (91.3%). Of the treatment-resistent 84 lesions, 67 presented a worsening stage shift over time. Indication for surgical intervention was set in 57 lesions. Of all lesions, 28 developed highly advanced necrotic bone destruction. Antiresorptive medication was paused in all evaluated patients after the first diagnosis of MRONJ. CONCLUSION: Conservative non-surgical therapy in MRONJ stage I leads to a healing in rare cases. Conservative management might be a good option to preserve symptoms in patients either unwilling to undergo surgery or in those whose reduced general condition does not allow surgery. Early and consequent surgical advances should be performed throughout all stages of the disease to prevent the possibility of silent disease progression with the risk of large-scale bone loss.

Accuracy of patient-specific implants and additive-manufactured surgical splints in orthognathic surgery - A three-dimensional retrospective study.

INTRODUCTION: Because of the many limitations of conventional surgery planning for the treatment of orthognathic deformities, as well as advancements in computer-assisted planning, there is an urgent need for technical devices that transfer the surgical plan into the operating theatre. In this regard, additive-manufactured, patient-specific implants (PSI) and additive-manufactured interocclusal splints represent promising approaches. The aim of this retrospective study was to compare the accuracy of these two devices, with regard to preoperative virtual treatment planning for maxillary Le-Fort I advancement surgery using IPS CaseDesigner®, and based on a new analysis method without the use of landmarks. MATERIALS AND METHODS: A retrospective evaluation of 18 class III patients (n(PSI) = 9; n(splint) = 9), who had undergone virtually planned orthognathic surgery (including maxillary Le Fort I advancement), was performed. The preoperative treatment plan and the postoperative outcome were combined to calculate the translational and rotational discrepancies between the 3D planning and the actual surgical outcome. RESULTS: For the PSI and splint groups the accuracy of left/right positioning was 0.51 mm ± 0.48 and 1.11 mm ± 1.32 respectively. The accuracy of anterior/posterior positioning was 0.39 mm ± 0.26 and 1.42 mm ± 0.87, and that of up/down-positioning was 0.44 mm ± 0.31 and 0.62 mm ± 0.47. The rotational discrepancies were less than 2° in both groups. CONCLUSION: The findings demonstrate that both PSI and splint approaches can accurately transfer the virtual planning into the operating theatre. However, PSIs show an overall higher accuracy, especially for anterior/posterior translational movement (p < 0.002).

Double-layer closure techniques after bone surgery of medication-related osteonecrosis of the jaw - A single center cohort study.

INTRODUCTION: Mucosal wound closure plays a key role after surgery of manifested medication-related osteonecrosis of the jaw (MRONJ). Additional soft tissue layers promise better vascularization and mechanical stability. The objectives of this study were to examine success rates of double-layer closure techniques in MRONJ patients, namely the mylohyoideus muscle flap (MMF) for the lower jaw and the pedicled buccal fat flap (BFF) for the upper jaw. MATERIALS AND METHODS: We designed and implemented a restrospective cohort study and enrolled a sample of patients diagnosed with MRONJ that were treated between 2015 and 2017 with either the MMF or the BFF after removal of the necrotic bone areal. Success was assessed as the maintenance of full mucosal coverage without signs of residual infection at (T0) four weeks (T1), four months (T2), and eight months (T3) after operation. The occurrence of side effects was evaluated. RESULTS: A total of 87 (MMF n = 57; BFF n = 30) patients with 104 MRONJ (MMF 68 = ; BFF n = 36) lesions were included. At the time of the last follow-up, 88.0% (44 of 50) of patients in the MMF group and 93.1% (27 of 29) of patients in the BFF group showed mucosal integrity. No serious side effects were reported. Overall treatment of earlier lesions (stage I and II) showed a better outcome than more severe necrosis (stage III). CONCLUSION: Double-layer closure techniques after surgery in MRONJ patients provide a mechanically stable, well-vascularized covering of the bone defect and should be considered as an option in the standard protocol for all degrees of severity of the disease.

Short- and long-term changes of the pharyngeal airway after surgical mandibular advancement in Class II patients-a three-dimensional retrospective study.

PURPOSE: To evaluate the short- and long-term impact of mandibular-only advancement on pharyngeal airway space (PAS) changes by using cone-beam computed tomography (CBCT) and a new segmentation software. Furthermore, to determine whether a correlation exists between forward movement and PAS gain. MATERIALS AND METHODS: A retrospective evaluation of a homogeneous cohort of Class II patients who had undergone mandibular-only advancement was performed. Pre- (T0), post- (T1), and 1-year post-operative (T2) CBCT scans were obtained in each case, and the changes in PAS parameters (volume and smallest cross-sectional area) were compared with new segmentation software. Mandibular advancement was measured and correlated with PAS parameters. RESULTS: A significant postoperative gain in all airway parameters compared with baseline was shown for T1 (p = 0.02), with an additional increase for T2 (p < 0.001). No significant linear association between the movement of the measurement points and any other PAS parameters could be discerned (p > 0.05). CONCLUSION: Our findings indicate that bilateral mandibular-only advancement surgery results in a significant widening of the PAS in Class II patients. Long-term adaption of the PAS also occurs after surgery implying an additional gain of PAS over time. Sicat Air® software seems to be a sufficient and promising tool for PAS evaluation.