Oral and maxillofacial surgery最新文献

{"title":"Anterior oblique osteotomy for mandibular advancements: highlighting a minimally invasive solution.","authors":"Jonathas Daniel Paggi Claus, Matheus Spinella Almeida, Hugo José Correia Lopes","doi":"10.1007/s10006-025-01397-5","DOIUrl":"10.1007/s10006-025-01397-5","url":null,"abstract":"<p><strong>Objective: </strong>Bilateral sagittal split osteotomy (BSSO) is widely used for mandibular advancements but is often associated with complications such as nerve disturbances, limited angle projection, and mandibular notching. This study describes a modification, the anterior oblique osteotomy (AOO), within the minimally invasive orthognathic surgery (MIOS) concept, addressing these challenges.</p><p><strong>Methods: </strong>A single-center retrospective study was conducted involving 30 patients who underwent bimaxillary surgery using AOO. Pre- and postoperative computed tomography scans were analyzed to measure the increase in posterior mandibular height.</p><p><strong>Results: </strong>The mean mandibular advancement was 7.8 mm, with no unfavorable splits or nerve injuries. All patients achieved full recovery of the inferior alveolar nerve by two weeks postoperatively. Significant improvements in posterior mandibular height were observed, increasing from 58.3 mm preoperatively to 67.2 mm postoperatively (p < 0.001). No cases of non-union, malunion, malocclusion, or relapse were reported during follow-up.</p><p><strong>Conclusions: </strong>The AOO technique, when applied within the MIOS framework, presents a viable alternative to traditional BSSO, it offers reduced morbidity and enhanced aesthetic results. Further studies, including control groups, are recommended to confirm the long-term stability of the vertical increase and clinical outcomes.</p>","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":"29 1","pages":"105"},"PeriodicalIF":0.0,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144113116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of timing of soft tissue augmentation on the width of keratinized mucosa around the dental implant.","authors":"Mohamed Ahmed Hafez El-Sayed, Wafaa Saleh, Samah ElMeadawy, Mohamed A Al-Shahat","doi":"10.1007/s10006-025-01401-y","DOIUrl":"10.1007/s10006-025-01401-y","url":null,"abstract":"<p><strong>Purpose: </strong>This study measures the impact of timing of free gingival graft (FGG) in improving aesthetics, function, and long-term stability of dental implants by measuring keratinized mucosa width (KMW), soft tissue thickness (STT), and graft shrinkage after implant treatment.</p><p><strong>Methods: </strong>The current randomized clinical trial included 20 patients with inadequate KMW and requiring placement of dental implant. The participants were randomly distributed into two groups. Group 1 received FGG 2 months before placing the dental implant while group 2 received the FGG at the second stage of implant surgery. The following parameters were evaluated and statistically analyzed at baseline, day 7, as well as 1, 3, 6, and 9 months postoperatively, KMW, STT and shrinkage percentage of the FGG.</p><p><strong>Results: </strong>Twenty patients with ages ranging from 30 to 55 years with reduced KMW were included in the current study. Both groups showed a significant increase in KMW and STT on day7, 1, 3, 6, and 9 months postoperatively while the intergroup comparison showed no significant differences in KWM, STT, and shrinkage percentage between both groups at the same point of time.</p><p><strong>Conclusion: </strong>The two study groups' outcomes demonstrated that the FGG can be placed either before or after dental implants to improve the soft tissue augmentation surrounding the implants. However, the implantologist should take patient preferences and long-term stability into consideration.</p>","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":"29 1","pages":"104"},"PeriodicalIF":0.0,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12092525/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144113119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Are tongue flaps effective in the closure of palatal fistulas? A systematic review and meta-analysis.","authors":"Feras AlMofreh AlQahtani, Sam Kuriadom, Michalis Mastrogeorgiou, Abubaker Abualgasim, Hanan Mr Shokier, Shadia A ElSayed","doi":"10.1007/s10006-025-01392-w","DOIUrl":"10.1007/s10006-025-01392-w","url":null,"abstract":"<p><strong>Purpose: </strong>Is to Sytematically review the available evidence on the effectiveness of tongue flaps in the Closure of Palatal Fisutlas.</p><p><strong>Methods: </strong>The study protocol was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols, and it was registered with the International Prospective Register of Systematic Reviews under registration number CRD42023397034.</p><p><strong>Results: </strong>Our search strategy yielded 587 articles. Of these, 150 were duplicate studies, and 437 were screened. Of these studies, 392 studies were excluded based on their titles and abstracts. 45 records were assessed for eligibility in which 29 were excluded as they did not meet the inclusion criteria. Finally, 16 studies met the criteria for inclusion, and they were critically reviewed.</p><p><strong>Conclusion: </strong>This study highlights that tongue flaps, particularly dorsal tongue flaps (DTF) and posterior tongue flaps (PTF), are effective options for palatal fistula closure, demonstrating high success rates and a favorable complication profile. Nonetheless, additional research is necessary to explore the potential of these techniques for closing oroantral fistulas (OAF). Further investigations should employ randomized controlled trials with larger patient cohorts and extended follow-up periods to comprehensively evaluate the efficacy, complication rates, and long-term outcomes of DTF and PTF in OAF treatment.</p>","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":"29 1","pages":"103"},"PeriodicalIF":0.0,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12089183/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144096825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Blood pressure and microvascular free flap perfusion in head and neck reconstruction- a retrospective analysis.","authors":"Mark Ooms, Philipp Winnand, Marius Heitzer, Nils Vohl, Marie Sophie Katz, Johannes Bickenbach, Frank Hölzle, Ali Modabber","doi":"10.1007/s10006-025-01378-8","DOIUrl":"10.1007/s10006-025-01378-8","url":null,"abstract":"<p><strong>Purpose: </strong>The influence of blood pressure on microvascular free flap perfusion is not fully understood and remains an ongoing topic of debate, as flap perfusion is both a prerequisite for flap viability and a parameter frequently used for postoperative flap monitoring. The aim of this study was to investigate the influence of blood pressure on microvascular free flap perfusion.</p><p><strong>Methods: </strong>Perfusion measurement data obtained with the Oxygen-2-see (O2C) analysis system intraoperatively and postoperatively in 244 patients who underwent microvascular reconstruction of the head and neck region with a fasciocutaneous free flap (FFF) or perforator free flap (PFF) between 2011 and 2020 were analyzed retrospectively. Blood pressure values (i.e., systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MBP)) and perfusion parameters (i.e., flap blood flow, hemoglobin concentration, and hemoglobin oxygen saturation) were evaluated to reveal potential associations.</p><p><strong>Results: </strong>Postoperative flap blood flow was associated with SBP, DBP, and MBP in PFFs (r = 0.245, p = 0.006; r = 0.239, p = 0.008; r = 0.295, p < 0.001, respectively). These associations also persisted in multivariable analysis (p = 0.036; p = 0.024; p = 0.004, respectively). Postoperative hemoglobin oxygen saturation was associated with SBP and MBP in PFFs (r = 0.253, p = 0.005; r = 0.189, p = 0.036, respectively). The association with SBP also persisted in multivariable analysis (p = 0.005).</p><p><strong>Conclusion: </strong>Microvascular free flap perfusion in PFFs, specifically postoperative flap blood flow and hemoglobin oxygen saturation, is influenced by blood pressure. This suggests that blood pressure might be an adjustable variable for the control of flap perfusion and should be considered as a confounding variable for flap monitoring based on flap perfusion in PFFs.</p>","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":"29 1","pages":"85"},"PeriodicalIF":0.0,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12102101/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144130030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Articaine use does not routinely eliminate the need for palatal injections for primary maxillary molar extractions: a randomized cross-over clinical trial.","authors":"Zahra Bahrololoomi,&nbsp;Nahid Maghsoudi","doi":"10.1007/s10006-021-01021-2","DOIUrl":"https://doi.org/10.1007/s10006-021-01021-2","url":null,"abstract":"<p><strong>Purpose: </strong>The aim of this study was to compare single buccal infiltration of 4% articaine versus routine buccal and palatal injections of 2% lidocaine during bilateral extraction of maxillary primary molars.</p><p><strong>Methods: </strong>Thirty healthy children aged 6-9 years old requiring bilateral extraction of maxillary primary molars were enrolled into the trial. Randomization was performed in two steps. Routine buccal and palatal infiltrations were administered using 2% lidocaine in the control side. Four percent articaine was used for single buccal infiltration in the intervention side. WBFP scale (Wong-Baker FACES Pain scale) was employed for subjective assessment of pain. For objective evaluation of pain, FLACC scale (Face, Legs, Activity, Cry, Consolability) and physiological parameters of blood pressure and pulse rate were recorded.</p><p><strong>Results: </strong>Analyses did not show any significant differences in blood pressure, pulse rate, and FLACC scale between groups (P value > 0.05). However, statistically lower WBFP scores were observed in articaine group as compared to lidocaine group (P value < 0.05); the difference was less than one unit which is not clinically considerable.</p><p><strong>Conclusion: </strong>Single buccal infiltration of 4% articaine can be administered as an alternative for conventional infiltration of 2% lidocaine to avoid fear or uncooperative behavior of the child patient. However, the assessment of palatal tissue anesthesia is quite necessary before the procedure is initiated. In case of failure in achieving palatal anesthesia, a palatal injection should be given.</p>","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":" ","pages":"603-611"},"PeriodicalIF":1.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8635313/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39683533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Do rural oral and maxillofacial surgeons prescribe more postoperative opioids?","authors":"Jack A Harris,&nbsp;Nisarg A Patel,&nbsp;David A Keith","doi":"10.1007/s10006-021-01033-y","DOIUrl":"https://doi.org/10.1007/s10006-021-01033-y","url":null,"abstract":"<p><strong>Purpose: </strong>This study assesses rural-urban differences in opioid prescription practices among oral and maxillofacial surgeons (OMSs) who treated Medicare beneficiaries in 2017.</p><p><strong>Methods: </strong>This cross-sectional study examines the 2017 Medicare Provider Utilization and Payment Dataset. The primary predictor variable was provider Rural-Urban Commuting Area code (rural versus urban). The primary outcome variable was mean opioid claims per Medicare beneficiary. Additional outcomes include total opioid claims volume, average Medicare beneficiaries and opioid cost per provider, mean days' supply of opioids per opioid claim, and average percentage of Medicare Part D claims represented by opioid claims. Mann-Whitney U tests compared continuous variables. A least-squares regression identified correlates of opioid claims volume.</p><p><strong>Results: </strong>Rural OMSs demonstrated a higher mean opioid claims per OMS and opioid cost per provider compared to urban surgeons. Urban OMSs prescribed a greater mean days' supply of opioids per opioid claim. A larger percentage of Medicare Part D claims were represented by opioid claims for rural OMSs compared to urban OMSs. There were no differences in mean opioid claims per Medicare beneficiary. Male provider gender, female Medicare beneficiary gender, total number of beneficiaries, and a higher hierarchical condition category score were correlated with increased opioid claims per Medicare beneficiary for urban providers only.</p><p><strong>Conclusion: </strong>Urban and rural OMSs prescribe a similar volume of opioids per Medicare beneficiary, with rural providers prescribing higher total volumes of opioids due to larger patient panels. This work indicates that rural and urban OMSs have similar opioid prescribing practices.</p>","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":" ","pages":"649-654"},"PeriodicalIF":1.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39949912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction to: Patients' quality of life improves after surgical intervention of stage III medication-related osteonecrosis of the jaw.","authors":"Stefan Moll,&nbsp;Steffen Mueller,&nbsp;Johannes K Meier,&nbsp;Torsten E Reichert,&nbsp;Tobias Ettl,&nbsp;Christoph Klingelhöffer","doi":"10.1007/s10006-021-01018-x","DOIUrl":"https://doi.org/10.1007/s10006-021-01018-x","url":null,"abstract":"","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":" ","pages":"681"},"PeriodicalIF":1.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9643258/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39674903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Massive macroglossia, a rare side effect of COVID-19: clinical, histologic, and genomic findings in COVID-19-positive versus COVID-19-negative patients.","authors":"Victoria A Mañón,&nbsp;David Chubb,&nbsp;Laura S Farach,&nbsp;Rachid Karam,&nbsp;Mary C Farach-Carson,&nbsp;Nadarajah Vigneswaran,&nbsp;Karan Saluja,&nbsp;Simon Young,&nbsp;Mark Wong,&nbsp;James C Melville","doi":"10.1007/s10006-021-01031-0","DOIUrl":"https://doi.org/10.1007/s10006-021-01031-0","url":null,"abstract":"<p><strong>Purpose: </strong>The primary purpose of this study is to identify if there is an underlying genetic predisposition for COVID-related macroglossia and if this susceptibility is higher among individuals of African heritage. Secondary objectives include determining if genetic testing of COVID-infected patients who are intubated and prone could identify patients with higher susceptibility to the development of macroglossia.</p><p><strong>Methods: </strong>A retrospective chart review was completed for each patient, and prospectively, genetic and histopathologic analyses were completed. Whole-exome sequencing was completed on two patients; immunohistochemistry was completed on the COVID-positive tissue samples.</p><p><strong>Results: </strong>Histopathology of the COVID-positive patient revealed significant peri-lymphocytic infiltrate, which was absent in the COVID-negative patient. Immunohistochemistry confirmed the presence of immune cells. Results from the whole-exome sequencing were inconclusive.</p><p><strong>Conclusion: </strong>The findings of this study are consistent with others that have observed a lymphocytic infiltrate in the organs of patients infected with SARS-CoV-2. On histology, IHC highlighted a CD45 + predominance, indicating that a robust immune response is present in the tissues. The pathobiology of this phenomenon and its role in the development and/or persistence of massive macroglossia requires further study.</p>","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":" ","pages":"613-618"},"PeriodicalIF":1.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8722658/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39783744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IgG4-related sialadenitis - a rare bilateral submandibular gland enlargement: case report.","authors":"Reema Mahmoud,&nbsp;Clariel Ianculovici,&nbsp;Shlomi Kleinman,&nbsp;Oren Peleg","doi":"10.1007/s10006-021-01020-3","DOIUrl":"https://doi.org/10.1007/s10006-021-01020-3","url":null,"abstract":"<p><p>Immunoglobulin G4-related disease (IgG4-RD) is a fibroinflammatory condition of unknown etiology. Although the salivary glands are currently considered among the most commonly affected among them, oral and maxillofacial surgeons are generally not familiar with the condition. Enlargement of the major salivary glands may be the first identifiable sign of IgG4-RD. A salivary gland biopsy along with IgG4 serum level assessment may help differentiate IgG4-related sialadenitis (IgG4-RS) from malignancies, infectious diseases, and obstructive conditions. Greater knowledge and higher levels of awareness of IgG4-RS may contribute to the expansion of differential diagnostic and treatment approaches. This case report describes a patient with bilateral submandibular salivary gland swelling who was diagnosed as having IgG4-RS on the basis of the histopathologic findings of a submandibular salivary gland biopsy and subsequent IgG4 levels.</p>","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":" ","pages":"673-677"},"PeriodicalIF":1.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39910139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NSAID chronotherapy after impacted third molar extraction: a randomized controlled trial.","authors":"Zaid Tamimi,&nbsp;Mohammad Abusamak,&nbsp;Haider Al-Waeli,&nbsp;Mohammad Al-Tamimi,&nbsp;Rola Al Habashneh,&nbsp;Mohammad Ghanim,&nbsp;Mohammed Al-Nusair,&nbsp;Qiman Gao,&nbsp;Belinda Nicolau,&nbsp;Faleh Tamimi","doi":"10.1007/s10006-021-01029-8","DOIUrl":"https://doi.org/10.1007/s10006-021-01029-8","url":null,"abstract":"<p><strong>Objectives: </strong>Postoperative pain management impacts patients' quality of life and morbidity. Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen are widely used for this following a 3-doses-per-day regime. However, pain and inflammation follow a circadian rhythm, and animal models assessing the scheduling of NSAID administration (e.g., chronotherapy) have shown that while their use during the active phase of the day enhances postoperative recovery, their administration during the resting phase could have detrimental effects. This observation has led us to hypothesize that night administration of NSAID might be unnecessary in post-surgical scenarios. Therefore, a randomized clinical trial was conducted to test this hypothesis in surgical third molar extractions.</p><p><strong>Materials and methods: </strong>Seventy (18-35 years) healthy participants requiring surgical removal of impacted lower third molars were recruited and randomized into a double-blind placebo-controlled study. For three days postoperatively, the treatment group (n = 33) received ibuprofen (400 mg) at 8 AM, 1 PM, and a placebo at 8 PM, while the control group (n = 37) received ibuprofen (400 mg) at 8 AM, 1 PM, and 8 PM. Pain severity was assessed by visual analog scale (VAS) and healing indicators including facial swelling, mouth opening, and C-reactive protein blood levels were also measured.</p><p><strong>Results: </strong>Pain VAS measures showed a circadian variation peaking at night. Also, no significant differences were observed between the two groups of the study in terms of postoperative pain scores (estimate: 0.50, 95% CI = [- 0.38, 1.39]) or any other healing indicator.</p><p><strong>Conclusions: </strong>Postoperative pain follows a circadian rhythm. Moreover, night administration of ibuprofen might not provide any significant benefits in terms of pain management and control of inflammation, and two doses during the day only could be sufficient for pain management after surgical interventions.</p><p><strong>Knowledge transfer statement: </strong>Even though this study cannot rule out the possibility that a reduced regime is different than a standard regime, nocturnal doses of ibuprofen seem to have no clinical significance in the short term, and the results of this study provide evidence in favor of reducing ibuprofen administration from three doses to two doses only after third molar surgery.</p>","PeriodicalId":520733,"journal":{"name":"Oral and maxillofacial surgery","volume":" ","pages":"663-672"},"PeriodicalIF":1.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39710008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}