Kobra Surgery Simulator-A Possibility to Improve Digital Teaching? A Case-Control Study.

Computer-aided simulations have long been of great importance in university teaching; however, to date, there is limited use of such simulations in the dental surgical sector. For this purpose, an oral surgery simulator, "Kobra", was implemented in student training and was evaluated for dental education. Dental students (group 1, third-year and group 2, fourth-year) and dentists of the faculty (control group) were trained to use the simulator. The outcomes for group 1 (apicoectomy of an upper lateral incisor with Kobra), group 2 (removal of an impacted lower wisdom tooth with Kobra) and the control group (both procedures with Kobra) were evaluated. For evaluation purposes, subjective parameters (improvement of practical skills, comparison between conventional training and Kobra simulation, and implementation of simulation-based teaching) and objective parameters (removal of bone, tooth substance and soft tissue measured while performing the Kobra simulation) were assessed using questionnaires with a scale ranging from 1-5. A total of 49 students (third-year n = 29, with 22 women and 7 men; fourth-year n = 20, with 17 women and 3 men) and 10 dentists (women n = 5 and men n = 5) participated. Compared to the Kobra simulation, the conventional training method with plastic models was still favored (the difference was non-significant). Compared to the dentists, the simulation data showed a less precise surgical performance of the students (the difference was not significant). The Kobra simulation may offer an additional method to conventional surgery training using plastic models, with benefits for students and faculty staff.

Lineage-associated connexin 43 expression in bisphosphonate-exposed rat bones.

Expression of signaling proteins in bone cells depends on their embryological mesoderm-derived (e.g. tibia) or cranial neural crest (CNC)-derived (e.g. jaw) origin. Connexin 43 (Cx43) is a gap junction protein that plays an essential role in the mode of action of bisphosphonates (BP). This study aimed to investigate Cx43 expression and the influence of BP application on mesoderm- and CNC-derived bone. Using a rat model, molar extraction and tibia osteotomy with (Group 4) or without (Group 3) previous BP application was performed. Untreated (Group 1) and animals selectively treated with BPs (Group 2) served as controls. Cx43 expression was immunohistochemically determined 12 and 16 weeks postoperatively via a labeling index. Cx43 expression in CNC-derived bone was significantly higher compared with mesodermal bone. BP application decreased Cx43 expression; however, detected expression levels were still higher in jawbone (Group 2 tibia vs jaw: 5.83 ± 5.06 vs 23.52 ± 6.42; p = 0.007). During bone healing after surgical intervention (Group 3) there were no expression differences between tibia and jawbone. BP treatment prior to surgery resulted in significantly lower Cx43 expression in CNC-derived compared with tibia bone (Group 4 tibia vs jaw: 56.84 ± 15.57 vs 16.40 ± 5.66; p < 0.01). Increased Cx43 expression in jaw compared with tibia bone is in line with their embryological origins. A significant Cx43 suppression in jawbone after BP application and surgery might contribute to the selectively altered osseous turnover and development of MRONJ in CNC-derived bone.

Endothelial inflammatory and thrombogenic expression changes in microvascular anastomoses - An immunohistochemical analysis.

The aim of this study was to investigate intraluminal vessel diameters and endothelial expression levels of pro-inflammatory and -thrombotic mediators in patent and non-patent microvascular anastomoses. Endothelial expression of CD31, VCAM-1, E- and P-Selectin, eNOS, iNOS and PAI-1 was evaluated by immunohistochemistry and compared to non-anastomosed arteries as controls. Intraluminal diameters were determined via H.E.-staining. In 20 human anastomoses (8 patent, 12 non-patent) neither the analysis of endoluminal de-endothelialization (p = 0.966) nor luminal narrowing (p = 0.750) revealed any significant differences between patent and non-patent microanastomoses. Expressions of pro-inflammatory mediators were significantly higher in patent anastomoses compared to controls but did not show any difference compared to non-patent anastomoses (p > 0.050). iNOS was higher in non-patent compared to patent anastomoses (p = 0.030) and controls (p = 0.001), whereas eNOS did not reveal any differences between these groups (p = 0.611 and p = 0.130). In non-patent anastomoses PAI-1 was expressed higher compared to patent anastomoses and controls (p = 0.021 and p < 0.001). Irrespective of their patency, anastomoses are characterized by endothelial dysfunction with a pro-inflammatory and pro-thrombotic milieu. Avoiding endothelial trauma during suturing is essential in order not to aggravate existing endothelial dysfunction in microanastomoses. Additionally, the influence of medication-related changes on anastomoses should be investigated as this is still an indistinctive topic.

The effect of polyethylenglycol gel on the delivery and osteogenic differentiation of homologous tooth germ-derived stem cells in a porcine model.

OBJECTIVES: The aim of this study was to investigate if bone regeneration can be promoted by homologous transplantation of STRO-1 sorted (STRO-1+) porcine tooth germ mesenchymal stem cells (TGSCs) with the combination of polyethylenglycol (PEG)-based hydrogel and biphasic calcium phosphate (BCP) scaffolds. MATERIAL AND METHODS: TGSCs were isolated from impacted third molars of domestic pigs. Nine critical-sized defects were created as (1) untreated defect; filled with (2) autogenous bone; (3) BCP + PEG; (4) BCP + PEG + unsorted TGSCs; (5) BCP + unsorted TGSCs; (6) BCP + PEG + STRO-1-sorted TGSCs; (7) BCP + STRO-1-sorted TGSCs; (8) BCP + PEG + osteogenic induced unsorted TGSCs; and (9) BCP + PEG + osteogenic induced STRO-1-sorted TGSCs in 20 domestic pigs. CM-DiI labelling was used to track cells in vivo. Histomorphometric assessment of new bone formation was achieved by toluidine blue O staining and microradiography after 1, 2, 4 and 12 weeks posttransplantation. RESULTS: Complete healing was achieved in all defects although defects with PEG hydrogel presented better bone formation while STRO-1+ and unsorted TGSCs showed similar ability to form new bone after 12 weeks. Transplanted cells were seen in defects where PEG hydrogel was used as carriers in contrast to defects treated with cells and only bone grafts. CONCLUSIONS: PEG hydrogel is an efficient carrier for homologous stem cell transplantation. TGSCs are capable of promoting bone healing in critical-sized defects in combination with bone graft and PEG hydrogel. CLINICAL RELEVANCE: This study provides information about the importance of the delivery vehicle for future translational stem cell delivery approaches.

Long-Term Influence of Platelet-Rich Plasma (PRP) on Dental Implants after Maxillary Augmentation: Implant Survival and Success Rates.

The atrophic maxilla often requires bone augmentation before implant placement to ensure long-term implant success. A previous prospective clinical trial examined the use of platelet-rich plasma (PRP) during maxillary augmentation. The short-term results showed no positive effect of PRP. The aim of this study was to evaluate the same patient collective of the previous study regarding the PRP long-term impact on the survival and success of dental implants. Fifty-three patients from the previous study diagnosed with maxillary atrophy and augmented with autologous bone grafts from the iliac crest and dental implants, were included in this study. Treatment was carried out on both sides in 34 patients with a split-mouth-design in which one randomly chosen side was treated additionally with PRP, the other side was the control-side. Nineteen patients were treated only on one side and were assigned to the PRP-or the control group randomly. Implant follow-up of the patients from the previous study was performed after an average time of 13 years. Implant success was evaluated using two different success criteria. Thitry-seven patients (25 women and 12 men) were investigated in this study. Seventeen patients (12 female, 5 male) were included in the PRP group, while 20 patients (13 female, 7 male) participated in the control group. A total of 210 implants were inserted. Of these, 102 implants (48.57%) were placed in the PRP group and 108 implants (51.42%) in the control group. Out of 102 investigated implants in the PRP group, 6 were removed (survival rate 94.1%). While two of the 108 implants in the control group were loss (survival rate 98.1%). In the PRP group, the cumulative probability of survival after 15.1 years was 94.1% and in the control group, was 98.1%, with no significant difference between the two groups. Higher significant difference for the control group was found in the cumulative success probability using Albrektson criteria (p = 0.05). Positive impact of PRP on long-term implant survival and success could not be found.

Long-Term Influence of Platelet-Rich Plasma (PRP) on Dental Implants after Maxillary Augmentation: Retrospective Clinical and Radiological Outcomes of a Randomized Controlled Clinical Trial.

: The long-term clinical and radiological outcomes of dental implants inserted in augmented bone treated with platelet-rich plasma (PRP) has not been well addressed in the literature yet. This study is based on a collection of patients from a randomized controlled trial (RCT) that did not report any short-term positive effects of PRP on bone healing after sinus lift surgery using autologous iliac crest bone graft. This study aimed to evaluate the long-term impact of PRP regarding clinical and radiological outcomes on the inserted implants in the previous RCT. For this evaluation, we considered the following variables: plaque index, probing depth, bleeding index, mobility grade, Periotest® values, and radiological bone loss. Out of 53 patients (n = 306 implants) included in the previous study we were able to reinvestigate 37 patients (n = 210 implants) in two centers (31 in Giessen, Germany and 6 in Erlangen, Germany). Clinical and radiographic parameters suggested overall healthy conditions of the peri-implant tissue. The PRP-group and the control group did not differ significantly in the majority of the parameters. The overall evaluation showed that result data of the PRP-group was inferior to the control group in 64 percent of the evaluated parameters. The present study cannot provide evidence of a positive effect of PRP on the long-term implant clinical and radiological outcomes. In fact, a tendency towards inferior long-term results in the PRP-group was detected without reaching a significant threshold. Further controlled trials need to be conducted to investigate this correlation.

Correction to: Long-term endothelial dysfunction in irradiated vessels: an immunohistochemical analysis.

Correction to: Strahlenther Onkol 2018 https://doi.org/10.1007/s00066-018-1382-3 The original version of this article unfortunately contained a mistake. The correct version of the Acknowledgements is given ….

Fluorescence-guided bone resection: A histological analysis in medication-related osteonecrosis of the jaw.

PURPOSE: Surgical treatment of medication-related osteonecrosis of the jaw (MRONJ) consists of necrotic bone removal followed by dense mucosal closure. Fluorescence-guided surgery has become a promising tool to intraoperatively distinguish between healthy and necrotic bone. Until now, there has been a lack of histopathological studies correlating the intraoperative fluorescence situation to histopathological analyses of the respective bone areas in order to further validate this method. MATERIALS AND METHODS: Histopathological sections from intraoperatively detected fluorescence- and non-fluorescence-labeled bone were analyzed detecting osteocyte and collagen content, RANK(L) and TRAP expression as well as proportion of immature bone regeneration. Samples were compared with viable-looking bone areas according to the intraoperative clinical situation. RESULTS: Staining revealed a significant decrease of osteocytes and collagen type-I fibers in necrotic, non-fluorescing areas compared to fluorescing bone (R/RGB [%]: 0.56 ± 0.38 (fluorescence positive) vs. 3.18 ± 2.22 (fluorescence negative), p = 0.041). Furthermore, the number of osteocytes was higher in fluorescing, clinically viable bone samples (cell/mm2: 151.26 ± 95.77 (fluorescence positive) vs. 0.56 ± 0.38 (fluorescence negative), p = 0.028). Additionally, the amount of immature bone was substantially increased in luminescent jaw bone (proportion of red [%]: 6.78 ± 7.00 (fluorescence positive) vs. 2.24 ± 1.36 (fluorescence negative), p = 0.442). RANK(L) and TRAP expression did not differ between the investigated areas, resembling a generalized decrease in osteocyte-osteoclast function all over the jaw (RANK(L) -positive cells per mm2: 8.97 ± 7.85 (fluorescence positive) vs. 7.76 ± 6.41 (fluorescence negative), p = 0.793; TRAP-positive cells per mm2: 0.36 ± 0.38 (fluorescence positive) vs. 0.33 ± 0.41 (fluorescence negative), p = 0.887). CONCLUSION: Intraoperative fluorescence-guided surgery might be more precise in identifying and resecting the necrotic bone compared to previous indicators like bone bleeding, which could be useful to further improve surgical therapy in MRONJ patients.

Collagen Matrix Vascularization in a Peri-Implant Vestibuloplasty Situation Proceeds Within the First Postoperative Week.

PURPOSE: Vestibuloplasty is a frequently performed surgical procedure to create or increase soft tissue mucosal sealing around dental restorations. Collagen matrices have exhibited comparable clinical results as free gingival grafts in the context of intraoral tissue augmentation. However, the process of matrix vascularization, the basic requirement for local healing, is incompletely understood. Therefore, this study investigated collagen matrix perfusion in a clinical intraoral setting. MATERIALS AND METHODS: In a prospective cohort study, vestibuloplasty was performed during implant exposure using prefabricated collagen matrices. Matric perfusion was determined intraoperatively and at days 2, 5, 7, 14, 30, and 90 using a laser Doppler spectrophotometer measuring oxygen saturation, relative amount of hemoglobin, blood flow, and blood velocity as primary outcome variables. These parameters were compared with perfusion of the oral mucosa surrounding the matrices. Statistical analysis was performed by applying variance and regression models. RESULTS: In 10 patients (average age, 60.9 yr), vestibuloplasty was performed exclusively in the anterior mandible. Blood flow and tissue oxygen saturation in the augmented zones markedly increased until postoperative day 5 and approximated perfusion values of the adjacent mucosa at the following 2 time points. Likewise, matrix oxygen saturation markedly increased until day 7 and subsequently converged to perfusion parameters of the surrounding mucosa at the following time points. CONCLUSION: Flow signals in incorporated collagen matrices occurred on day 2 after vestibuloplasty and further increased until days 5 to 7. Therefore, matrix perfusion mainly occurs within the first postoperative week, converging to perfusion levels of the surrounding mucosa with minimal alterations during the following course.

Papilla-Crown Height Dimensions around Zirconium Dioxide Implants in the Esthetic Area: A 3-Year Follow-Up Study.

PURPOSE: Soft tissue interactions with ceramic dental implants have previously been shown to have favorable esthetic outcomes. This study aimed to evaluate the papilla-crown proportion around zirconia implants in a 3-year follow-up study and the correlation between the gingival biotype and changes in papillary height. MATERIALS AND METHODS: This was a prospective study of 39 patients with 40 single-gap implants (Straumann PURE Ceramic ZLA Implant). The papilla-crown proportion was assessed after 3 months, 1 year, and 3 years. In addition, correlations between the peri-implant biotypes and changes in papillary heights were evaluated. RESULTS: The papilla-crown proportion improved from 35.5% after 3 months to 41.7% after 3 years. The gingival biotype was correlated very weakly to papilla height alterations. Significant papillary fill was observed in the interdental space between 3 months and 3 years (p < 0.001). CONCLUSIONS: An ideal papilla-crown proportion of 40% around single implants was observed after 3 years. A thin or thick gingival biotype showed a very weak correlation with soft tissue alterations.

Long-term endothelial dysfunction in irradiated vessels: an immunohistochemical analysis.

BACKGROUND: Microvascular free flap reconstruction has become a standard technique in head and neck reconstructive surgery. Pre-operative radiotherapy is associated with a higher incidence of free flap malperfusion and the need for operative revision. Irradiated vessels present characteristic histomorphological and structural changes. Alterations in endothelial cells of irradiated arteries remain incompletely investigated especially with regard to long-term changes in endothelial dysfunction supporting an intraluminal pro-thrombotic and pro-inflammatory milieu. METHODS: Endothelial expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E­ and P­selectin, endothelial NO-synthase (eNOS), thrombomodulin and plasminogen activator inhibitor-1 (PAI-1) in irradiated and non-irradiated arteries was analysed using immunohistochemistry and Remmele scale grading. The average radiation dose was 58.7 ± 7.0 Gy; the time interval between end of radiation and tissue sampling was 106.0 ± 86.8 months. RESULTS: Endothelial expression of ICAM-1, VCAM-1, E­ and P­selectin as well as PAI-1 was significantly increased in previously irradiated arteries compared with non-irradiated controls, whereas thrombomodulin and eNOS expression did not show any differences. However, when comparing non-irradiated free flap arteries with irradiated arteries from the head and neck area in respective individuals, eNOS expression was significantly lower in irradiated vessels whereas ICAM-1, VCAM-1, E­/p-Selectin and PAI-1 showed significantly higher expression levels. CONCLUSION: There is ongoing endothelial dysfunction in terms of increased expression of pro-thrombotic and pro-inflammatory markers in irradiated arteries even years after radiotherapy. Treating this endothelial dysfunction might reduce the complication rates associated with microvascular free flap reconstructions in irradiated patients.

The fitting accuracy of pre-bend reconstruction plates and their impact on the temporomandibular joint.

BACKGROUND: Various causes for bone defects of the lower jaw have been described. As a result, patients often suffer from compromised aesthetics and a loss of, or reduction in, important physiological functions, such as swallowing, breathing, and speaking. A change in the shape of the lower jaw can impair the natural occlusion and leads to an atypical or modified position of the temporomandibular joint. Titanium reconstruction plates are the standard approach to jaw reconstruction, and are used for temporary bridging of a jaw defect or fixation of a bone graft. Conventionally these plates are intraoperatively adjusted to the mandible by the surgeon. Computer-aided manufacturing, computer-aided design, and rapid prototyping have gained increasing importance in the field of medicine, as they allow the production of individual models of the lower jaw, with the possibility of preoperatively bending the reconstruction plates. In this retrospective study, the accuracy of pre-bent titanium plates and their effect on the temporomandibular joint situation in comparison with intraoperatively curved plates will be discussed. MATERIALS AND METHODS: Patients who attended our department for lower jaw reconstruction between March 2013 and February 2015 were included in this retrospective study. Within that time 20 patients were treated with pre-bent reconstruction plates (group 1). 20 comparable patients were selected with reconstruction and conventional intraoperative bending (group 2). To evaluate the accuracy of the plates and the condylar position, postoperative cone beam computed tomograms and computed tomograms were used to assess the bone-plate distance at 12 defined points and four angles in axial reconstruction. The results were compared, statistically evaluated, and discussed. RESULTS: Regarding the maximum bone-plate distances and the sum of distances, there was a significant difference between the accuracy of the pre-bent and the conventionally bent reconstruction plates (p = 0.022, p = 0.048). Regarding the condylar position, there was no significant difference between both methods (p = 0.867). CONCLUSION: The results of this study show that a better fitting accuracy can be achieved using pre-bent plates. Preparation of the plates proves to be advantageous and meaningful, especially in complex bone defects and deformations of the lower jaw. Nevertheless, concerning the position of the temporomandibular joint, no significant difference could be ascertained between the shown methods, contradicting several studies.

Correction to: Anatomical locations in the oral cavity where surgical resections of oral squamous cell carcinomas are associated with a close or positive margin-a retrospective study.

The following note was inadvertently omitted from the published paper: This work was performed in (partial) fulfillment of the requirements for the first author's obtaining the degree Dr. med. dent.

Galectin 3 expression in regional lymph nodes and lymph node metastases of oral squamous cell carcinomas.

BACKGROUND: Neck dissection is standard in surgical management of oral squamous cell carcinomas (oscc). However, the immunologic link between primary tumor and lymph nodes is insufficiently understood. Galectin 3 (Gal3) promotes M2 polarization of macrophages and contributes to immunosuppression. The current study analyzes the association between Gal3 expression in regional lymph nodes of oscc with histomorphologic parameters (T-, N-, L- Pn-stage, grading) of the primary tumor. Additionally, Gal3 expression is correlated with markers of macrophage polarization (M1 vs. M2). METHODS: Preoperative diagnostic biopsies (n = 26), tumor resection specimens (n = 34), tumor-free lymph nodes (n = 28) and lymph node metastases (n = 10) of T1/T2 oscc patients were immunohistochemically analyzed for Gal3 and macrophage marker (CD68, CD11c, CD163 and MRC1) expression. The number of positive cells and the expression ratios were quantitatively assessed. RESULTS: High Gal3 expression in tumor-free regional lymph nodes was significantly (p < 0.05) associated with increased tumor size. The epithelial compartment of lymph node metastases showed a significantly (p < 0.05) increased Gal3 expression compared to biopsies and tumor resection specimens. Cell density of M2 macrophages was significantly (p < 0.05) and positively correlated with the number of Gal3 expressing cells in lymph nodes and tumor specimens. CONCLUSION: Gal3 expression in regional lymph nodes might be associated with oscc progression. The increased Gal3 expression in regional lymph nodes of larger tumors underlines the need of immunomodulatory treatment concepts in early-stage oscc. Blocking of Gal3 might be a therapeutic option in oral cancer.

Diagnosis, avoidance and management of complications of implant-based treatments.

This review provides an overview of review and consensus articles of the past 5 years regarding surgical complications in implant dentistry. The focus in this article is on surgical complications occurring after implant insertion and on risk factors that compromise oral implant osseointegration.

Oral implant survival in patients with bisphosphonate (BP)/antiresorptive and radiation therapy and their impact on osteonecrosis of the jaws. A systematic review.

AIM: In this systematic review, we aimed to assess the impact of endosseous implants on the formation of an osteonecrosis of the jaw, as well as implant survival rates for patients under bisphosphonate (BP), antiresorptive and radiation therapy. MATERIALS AND METHODS: An electronic search was performed using PubMed, Embase, and Medline databases with the logical operators: "dental implant", "antiresorptive", "bisphosphonate", "irradiation", "radiotherapy", "radiation", "necrosis" and "survival". The search was limited to articles published up to 15 December 2016. Recent publications were also searched manually to find any relevant studies that might have been missed using the search criteria noted above. The outcome variables were the implant survival rate and the frequency of osteonecrosis of the jaws. RESULTS: In total, 18 studies addressing oral implants in patients with BP or antiresorptive therapy and 23 with radiation therapy met the inclusion criteria and were included in this systematic review. Most of the studies had a retrospective design with a level of evidence (LoE) of III (moderately high risk of bias). Implant survival rate ranged from 92.86% to 100% in patients with BP/antiresorptive therapy (all due to osteoporosis) and 38.5% to 97.9% in patients with radiation therapy. For BP patients, osteonecrosis in relation to oral implants more frequently occurred in patients taking BPs due to malignant diseases. In patients with radiation therapy, an "implant triggered" necrosis is also a potential complication. The lack of data in the current literature concerning this issue does not allow a proper risk assessment to date. CONCLUSIONS: Within the limits of this systematic review, implant treatment concepts seem to be a valuable approach in patients with radiation therapy and patients with BP therapy due to an osteoporosis. In patients taking BPs due to a malignant disease, implant treatments are not recommended due to the high number of reported implant-related necrosis in this patient cohort. Outcomes of this review should, however, be regarded with caution due to the low level of evidence of the currently existing data.

Correlation between pain and MRI findings in TMD patients.

INTRODUCTION: Magnetic resonance imaging has been established as the gold standard for assessment of the temporomandibular joint. Apart from an excellent assessment of the soft tissues it has the advantage not to expose the patient to ionizing radiation. There is a lack of literature concerning the correlation between pain intensity and radiological findings of the temporomandibular joint. Moreover there is the question of whether a progressive degeneration of the cartilaginous components is accompanied by an increasing degeneration of the osseous parts of the mandibular joint and vice versa. Therefore, this study aims at analyzing correlations between pain and radiological findings. Furthermore, the link between osseous and cartilaginous degeneration is studied. MATERIALS AND METHODS: 91 patients who attend our outpatient clinic for temporomandibular disorders are included in this prospective study. Apart from a detailed anamnesis and clinical examination - adapted to the Research Diagnostic Criteria for Temporomandibular Disorders -magnetic resonance imaging of both mandibular joints is performed. Pain intensity is measured using the visual analog scale. To assess and grade the radiological findings a classification system is established. The evaluation of the osseous components is based on the classification of osteoarthritis by Kellgren and Lawrence whereas the rating of the cartilaginous components is adapted to the Research Diagnostic Criteria for Temporomandibular Disorders. Correlations are verified by Spearman-Rho. RESULTS: 83,5% of all patients are female. Most of the time, both sides are affected (47.25%). Women state an average pain of 5.7 (±2.4), men 3.5 (±2.5). 182 discs are examined and assessed with our classification system. Most discs (n = 71) show no pathological changes. The majority of patients show no dislocation (n = 104). The most common forms of dislocation are anterior dislocations (n = 51). The majority of patients show no changes in the osseous component (n = 115). Weak to moderate correlations are found between disc and bone degeneration. Moderate to strong correlations are found between left and right TMJ. CONCLUSIONS: The classification system which is designed and applied during the study proves to be a reliable and practical Instrument. A standardized evaluation of pathologies concerning the temporomandibular joint is possible by using this system. Numerous patients attending our outpatient clinic do not show any signs of degenerative dysfunctions in the mandibular joints. Degenerations of the osseous components tend to be connected with degenerations of the cartilaginous components and vice versa. The question remains if in the future new procedures in imaging will be able to record pathologies not yet detected.

Evaluation of Staff Satisfaction After Implementation of a Surgical Safety Checklist in the Ambulatory of an Oral and Maxillofacial Surgery Department and its Impact on Patient Safety.

PURPOSE: Safety checklists in medicine have been shown to be effective in the prevention of complications and adverse events in patients undergoing surgery. Such checklists are not as common in dentistry. The aims of this study were to propose a safety checklist for the ambulatory treatment of patients undergoing oral and implant surgery and to assess its impact on patient safety and staff satisfaction. MATERIALS AND METHODS: After implementation of a surgical safety checklist in the ambulatory treatment of patients undergoing oral and implant surgeries, a questionnaire regarding staff satisfaction and safety-related parameters was randomly administered. Incidents, complications, and adverse events were documented. Outcomes with (n = 40 surgeries) and without (n = 40 surgeries) use of the checklist were analyzed and compared. RESULTS: Staff reported high satisfaction with the use of the checklist, which demonstrably improved team communication and lowered stress levels during surgery. There was a statistically significantly higher frequency of reported incidents without the use of the checklist (n = 43) than with the use of the checklist (n = 10; P = .000). Most incidents were reported in the context of pre- and post-procedural processes. CONCLUSIONS: Safety checklists help to improve work processes, optimize communication, and lower stress levels. Their use in clinical dental practice is recommended.

Anatomical locations in the oral cavity where surgical resections of oral squamous cell carcinomas are associated with a close or positive margin-a retrospective study.

OBJECTIVES: This study aimed to identify anatomical areas where resections of oral squamous cell carcinomas (OSCC) are significantly associated with close or positive margins. MATERIALS AND METHODS: This retrospective study included 330 patients with a primary OSCC from 2010 to 2015. Patient and tumour data were categorised into three groups by R-status (R0 [clear], ≥ 5 mm, 185 patients [56.06%]; R1 [positive], < 1 mm, 24 patients [7.27%]; and R0 [close], 1-5 mm, 121 patients [36.67%]). RESULTS: Areas where resections were significantly associated with close or positive margins were the hard palate (p < 0.001), buccal mucosa (p = 0.03), floor of the mouth (p = 0.004), lower alveolar ridge (p = 0.01), retromolar triangle (p = 0.005), and dorsal tongue (p = 0.02). CONCLUSIONS: Anatomical areas were identified in the oral cavity where it is challenging to resect OSCCs with an adequate safety margin. CLINICAL RELEVANCE: These results may enable surgeons to achieve a postulated safe distance during tumour resection, leading to a survival benefit for patients.