Impact of antithrombotic therapy on acute and delayed intracranial haemorrhage and evaluation of the need of short-term hospitalisation based on CT findings after mild traumatic brain injury: experience from an oral and maxillofacial surgery unit.

PURPOSE: The primary aim was to compare the prevalence of acute and delayed intracranial haemorrhage (ICH) following mild traumatic brain injury (mTBI) in patients on antithrombotic medication referred to a clinic for oral and plastic maxillofacial surgery. The secondary aim was to evaluate the need for short-term hospitalisation based on initial radiological and clinical findings. METHODS: This was an observational retrospective single-centre study of all patients on antithrombotic medication who were admitted to our department of oral and plastic maxillofacial surgery with mTBI over a 5 year period. Demographic and anamnesis data, injury characteristics, antithrombotic medication, radiological findings, treatment, and outcome were analysed. Patients were divided into the following four groups based on their antithrombotic medication: (1) single antiplatelet users, (2) vitamin K antagonist users, (3) direct oral anticoagulant users, and (4) double antithrombotic users. All patients underwent an emergency cranial CT (CT0) at admission. Based on clinical and radiological evaluation, different treatment protocols were applied. Patients with positive CT0 findings and patients with secondary neurological deterioration received a control CT (CT1) before discharge. Acute and delayed ICH and patient's outcome during hospitalisation were evaluated using descriptive statistical analysis. RESULTS: A total of 696 patients (mean age, 71.6 years) on antithrombotic medication who presented at our department with mTBI were included in the analysis. Most injuries were caused by a ground-level fall (76.9%). Thirty-six patients (5.1%) developed an acute traumatic ICH, and 47 intracerebral lesions were detected by radiology-most of these in patients taking acetylsalicylic acid. No association was detected between ICH and antithrombotic medication (p = 0.4353). In total, 258 (37.1%) patients were admitted for 48 h in-hospital observation. The prevalence of delayed ICH was 0.1%, and the mortality rate was 0.1%. Multivariable analysis identified a Glasgow Coma Scale (GCS) of < 15, loss of consciousness, amnesia, headache, dizziness, and nausea as clinical characteristics significantly associated with an increased risk of acute ICH, whereas age, sex, and trauma mechanism were not associated with ICH prevalence. Of the 39 patients who underwent a control CT1, most had a decreasing or at least constant intracranial lesion; in three patients, intracranial bleeding increased but was not clinically relevant. CONCLUSION: According to our experience, antithrombotic therapy does not increase the rate of ICH after mTBI. A GCS of < 15, loss of consciousness, amnesia, headache, dizziness, and nausea are indicators of higher ICH risk. A second CT scan is more effective in patients with secondary neurological deterioration. Initial CT findings were not clinically relevant and should not indicate in-hospital observation.

Evaluation of Different Patterns of Zygomaticoorbital Complex Fractures.

Study Design: Very few studies exist regarding the fracture pattern variability of the zygomaticoorbital (ZMO) complex. The retrospective evaluation of a large series of surgically treated unilateral ZMO fractures would in certain circumstances help intraoperative predictability and define sensitive indicators for open reduction and internal fixation. Objective: The aim of this study was to investigate the different fracture patterns after ZMO complex injury regarding the 5 anatomic sutures of the zygoma as well as the concomitance of the paranasal buttress and maxillary sinus wall fracture. Methods: The medical records of all patients with unilateral ZMO fractures who underwent surgical intervention in a single trauma center department between April 2015 and June 2020 were retrospectively reviewed. Demographic and anamnesis data, radiologic findings, and surgical reports were evaluated. According to the preoperative radiologic evaluation, ZMO fractures were classified as unisutural, bisutural, trisutural, tetrasutural, and complete based on the number of zygomatic sutures. The prevalence of various fracture patterns was analyzed. The impact of patient's age and trauma etiology on the fracture pattern was evaluated using descriptive statistical analysis. Results: The study included 492 patients with unilateral ZMO fractures, with a mean age of 49.93 years (SD = 20.66) and a male:female ratio of 2.23:1. The most affected age group was 19-44 years (41.67%) and tripping falls were the most common etiology (27.24%). Trisutural (57.32%) and unisutural fractures (23.17%) were the most common, followed by tetrasutural (8.94%), bisutural (8.54%), and complete fractures (2.03%). A trisutural fracture involving the zygomaticomaxillary suture, the infraorbital rim, and the zygomaticosphenoidal suture was the most common fracture pattern (52.03%). Most fractures were observed in the zygomaticosphenoidal suture (86.99%), followed by the infraorbital rim (74.59%) and the zygomaticomaxillary suture (68.29%). Fractures of the maxillary sinus wall and the paranasal buttress co-existed in 9.55% and 31.30% of all cases, respectively. No correlation was detected between age and fracture pattern (P = .4111). Tripping falls and bicycle accidents significantly influenced the fracture pattern (P < .0001). Conclusions: According to the results, knowledge of the fracture pattern variability of the ZMO complex could in certain circumstances designate CT or CBCT as mandatory before operating on ZMO fractures. Consequently, unnecessary incisions could be avoided. The high concomitance of paranasal buttress fracture also suggests its intraoperative surgical exploration. Further studies should correlate the clinical findings with indication for surgery and postoperative outcome for the different fracture patterns described.

Airway Management of Orofacial Infections Originating in the Mandible.

The primary aim of this study was to assess the incidence of a difficult airway and emergency tracheostomy in patients with orofacial infections originating in the mandible, and a secondary aim was to determine the potential predictors of difficult intubation. This retrospective single-center study included all patients who were referred between 2015 and 2022 with an orofacial infection originating in the mandible and who were surgically drained under intubation anesthesia. The incidence of a difficult airway regarding ventilation, laryngoscopy, and intubation was analyzed descriptively. Associations between potential influencing factors and difficult intubation were examined via multivariable analysis. A total of 361 patients (mean age: 47.7 years) were included in the analysis. A difficult airway was present in 121/361 (33.5%) patients. Difficult intubation was most common in patients with infections of the massetericomandibular space (42.6%), followed by infections of the mouth floor (40%) and pterygomandibular space (23.5%). Dyspnea and stridor were not associated with the localization of infection (p = 0.6486/p = 0.4418). Multivariable analysis revealed increased age, restricted mouth opening, higher Mallampati scores, and higher Cormack-Lehane classification grades as significant predictors of difficult intubation. Higher BMI, dysphagia, dyspnea, stridor and a non-palpable mandibular rim did not influence the airway management. Patients with a difficult airway were more likely to be admitted to the ICU after surgery than patients with regular airway were (p = 0.0001). To conclude, the incidence of a difficult airway was high in patients with orofacial infections originating in the mandible. Older age, limited mouth opening, a higher Mallampati score, and a higher Cormack-Lehane grade were reliable predictors of difficult intubation.

Clinical Indicators for Primary Cranial CT Imaging after Mild Traumatic Brain Injury-A Retrospective Analysis.

The primary aim was to determine the clinical indicators for primary cranial CT imaging in patients after mild traumatic brain injury (mTBI). The secondary aim was to evaluate the need for post-traumatic short-term hospitalization based on primary clinical and CT findings. This was an observational retrospective single-centre study of all the patients who were admitted with mTBI over a five-year period. Demographic and anamnesis data, the clinical and radiological findings, and the outcome were analyzed. An initial cranial CT (CT0) was performed at admission. Repeat CT scans (CT1) were performed after positive CT0 findings and in cases with in-hospital secondary neurological deterioration. Intracranial hemorrhage (ICH) and the patient's outcome were evaluated using descriptive statistical analysis. A multivariable analysis was performed to find associations between the clinical variables and the pathologic CT findings. A total of 1837 patients (mean age: 70.7 years) with mTBI were included. Acute ICH was detected in 102 patients (5.5%), with a total of 123 intracerebral lesions. In total, 707 (38.4%) patients were admitted for 48 h for in-hospital observation and six patients underwent an immediate neurosurgical intervention. The prevalence of delayed ICH was 0.05%. A Glasgow Coma Scale (GCS) of <15, loss of consciousness, amnesia, seizures, cephalgia, somnolence, dizziness, nausea, and clinical signs of fracture were identified as clinical factors with significantly higher risk of acute ICH. None of the 110 CT1 presented clinical relevance. A GCS of <15, loss of consciousness, amnesia, seizures, cephalgia, somnolence, dizziness, nausea, and clinical signs of cranial fractures should be considered absolute indicators for primary cranial CT imaging. The reported incidence of immediate and delayed traumatic ICH was very low and hospitalization should be decided individually considering both the clinical and CT findings.

Justification of Indication for Cranial CT Imaging after Mild Traumatic Brain Injury According to the Current National Guidelines.

The primary aim was to evaluate the compliance of cranial CT indication with the national guideline-based decision rules in patients after mTBI. The secondary aim was to determine the incidence of CT pathologies among justified and unjustified CT scans and to investigate the diagnostic value of these decision rules. This is a retrospective, single-center study on 1837 patients (mean age = 70.7 years) referred to a clinic of oral and maxillofacial surgery following mTBI over a five-year period. The current national clinical decision rules and recommendations for mTBI were retrospectively applied to calculate the incidence of unjustified CT imaging. The intracranial pathologies among the justified and unjustified CT scans were presented using descriptive statistical analysis. The performance of the decision rules was ascertained by calculating the sensitivity, specificity, and predictive values. A total of 123 intracerebral lesions were radiologically detected in 102 (5.5%) of the study patients. Most (62.1%) of the CT scans strictly complied with the guideline recommendations, and 37.8% were not justified and likely avoidable. A significantly higher incidence of intracranial pathology was observed in patients with justified CT scans compared with patients with unjustified CT scans (7.9% vs. 2.5%, p < 0.0001). Patients with loss of consciousness, amnesia, seizures, cephalgia, somnolence, dizziness, nausea, and clinical signs of cranial fractures presented pathologic CT findings more frequently (p < 0.05). The decision rules identified CT pathologies with 92.28% sensitivity and 39.08% specificity. To conclude, compliance with the national decision rules for mTBI was low, and more than a third of the CT scans performed were identified as "likely avoidable". A higher incidence of pathologic CT findings was detected in patients with justified cranial CT imaging. The investigated decision rules showed a high sensitivity but low specificity for predicting CT pathologies.

Factors Influencing Recurrence after Surgical Treatment of Odontogenic Maxillary Sinusitis: An Analysis from the Oral and Maxillofacial Surgery Point of View.

The aim of the study was to determine the factors influencing the development of recurrence after the surgical treatment of odontogenic maxillary sinusitis in an oral and maxillofacial surgery clinic over a 7-year period. Demographic and anamnesis data, clinical and radiological findings, treatment and outcome were analyzed. A multivariable analysis was performed to find associations between patient age, causative focus, surgical access for sinus revision, multilayer closure with a buccal fat pad, inferior meatal antrostomy (IMA) for temporary sinus drainage and sinusitis recurrence. A total of 164 patients with a mean age of 51.7 years were included. Sinusitis recurrence was observed in nine patients (5.48%) within 6 months after primary surgery. No significant correlation was detected between patient age, causative focus, surgical access for sinus revision, multilayer closure with a buccal fat pad, IMA for sinus drainage and the development of recurrence (p > 0.05). Patients with a history of antiresorptive-related osteonecrosis of the jaw showed a significant tendency toward disease recurrence (p = 0.0375). In conclusion, except for antiresorptive administration, none of the investigated variables were related to a higher risk of sinusitis recurrence. We encourage a combined approach of intraoral removal of the infective focus and sinus drainage via FESS, as well as an individual treatment decision in a multidisciplinary setting with collaboration between dentistry, maxillofacial surgery and otorhinolaryngology to avoid sinusitis recurrence.

Management of older adults after mild head trauma in an oral and maxillofacial surgery clinic.

PURPOSE: The primary aim was to determine the incidence of intracranial hemorrhage (ICH) after mild traumatic brain injury (mTBI) in patients aged ≥ 65 years. The secondary aim was to identify risk factors for intracranial lesions and evaluate the need for in-hospital observation in this age group. METHODS: This observational retrospective single-center study included all patients aged ≥ 65 years who were referred to our clinic for oral and plastic maxillofacial surgery following mTBI over a five-year period. Demographic and anamnesis data, clinical and radiological findings, and treatment were analyzed. Acute and delayed ICH and patient outcomes during hospitalization were evaluated using descriptive statistical analysis. A multivariable analysis was performed to find associations between CT findings and clinical data. RESULTS: A total of 1,062 patients (55.7% male, 44.2% female) with a mean age of 86.3 years were included in the analysis. Ground-level fall was the most frequent cause of trauma (52.3%). Fifty-nine patients (5.5%) developed an acute traumatic ICH, and 73 intracerebral lesions were radiologically observed. No association was detected between ICH rate and antithrombotic medication (p = 0.4353). The delayed ICH rate was 0.09% and the mortality rate was 0.09%. Significant risk factors for increased ICH were a Glasgow Coma Scale score of < 15, loss of consciousness, amnesia, cephalgia, somnolence, dizziness, and nausea according to multivariable analysis. CONCLUSION: Our study showed a low prevalence of acute and delayed ICH in older adults with mTBI. The ICH risk factors identified here should be considered when revising guidelines and developing a valid screening tool. Repeat CT imaging is recommended in patients with secondary neurological deterioration. In-hospital observation should be based on an assessment of frailty and comorbidities and not on CT findings alone.

Massive macroglossia after palatoplasty: case report and review of the literature.

UNLABELLED: Cleft palates are among the most common birth defects. Serious complications in perioperative airway management after palatoplasty are rare and mostly described in children with preexisting compromise of airway due to craniofacial anomalies. A very uncommon but typical and frightening complication is postoperative extreme, very rapid emergence, and life-threatening macroglossia. While macroglossia usually has its peak within 24-48 h after palatoplasty and resolves spontaneously, we report a patient with massive lingual swelling with complete obstruction of the upper airway on the fifth postoperative day requiring tracheotomy. Swelling only resolved after removing the endotracheal tube after tracheotomy. Next to the description of our case, we discuss standard care procedure in perioperative management of patients with cleft palate to prevent this life-threatening complication after palatoplasty. CONCLUSION: Macroglossia can occur even 3-5 days after surgery and can be maintained by the pressure of the endotracheal tube to the tongue ground. Knowledge and avoidance of these risk factors are as important as early treatment of respiratory compromise.

CBCT device dependency on the transfer accuracy from computer-aided implantology procedures.

OBJECTIVES: To evaluate the potential influence of different cone-beam computed tomography (CBCT) devices on the transfer accuracy of an open-source system for computer-aided implantology (CAI). MATERIAL AND METHODS: A total of 108 implants in 18 partially edentulous patient-equivalent models were planned and fully guided implants were inserted using an open-source CAI system with three different CBCT devices. After follow-up CBCT and fiducial marker-matching procedure, linear horizontal, vertical, and maximal three-dimensional deviations, as well as angle deviations between the virtual planning data and the surgical results were calculated. Variance analysis was carried out to prove whether or not the observed differences between the CBCT devices were statistically significant. RESULTS: The observed mean three-dimensional deviation rates between virtually planned and achieved implant positions varied by around 400 µm (45%) at the implant's base and around 540 µm (50%) at the implant's tip in dependence to the applied CBCT device. Mean vertical deviations varied around 370 µm (76%) at the implant's base and 350 µm (69%) at the implant's tip, whereas axes deviations varied around 0.81° (40%) between the three investigated CBCT devices. Except for the axes deviations and the horizontal linear deviations at the implants base, observed differences reached significance level between the CBCT devices. CONCLUSIONS: Until now, the potential influence from different CBCT devices on the transfer accuracy of CAI systems has not yet been investigated. Data from the present study confirm for the first time the in vitro CBCT device dependency on the transfer accuracy of CAI systems reaching up to axes deviations of 0.6 angle degree and linear deviations around half a millimeter.

Tocilizumab: Another medication related to osteonecrosis of the jaws? A case report and literature review.

Introduction: Medication-related osteonecrosis of the jaw (MRONJ) is a serious complication in patients receiving antiresorptive medication, such as bisphosphonates and denosumab, for different oncologic and non-oncologic diseases. Here, we report a case of MRONJ in a patient treated with tocilizumab, a humanized anti-interleukin-6 receptor antibody that effectively treats moderate to severe rheumatoid arthritis in adults. Case description: A 45-year-old female patient diagnosed with severe rheumatoid arthritis, who had been undergoing intravenous tocilizumab therapy for three years without history of bisphosphonate use, was referred to our department. Four weeks previously, several teeth in the maxilla and mandible were removed under local anesthesia by her dentist. Two weeks after the extractions, she felt pain in both jaws. We diagnosed wound dehiscence and delayed healing of the alveolar bone after the tooth extractions. Digital volume tomography showed persistent dry alveolar sockets. The patient underwent surgical debridement of necrotic bone, and intravenous antibiotics were administered in hospital. Five months later, wound dehiscence reoccurred in the same regions. Histopathological analysis of bone biopsies revealed a diagnosis of MRONJ. Four months later, wound dehiscence occurred in the left maxillary alveolar ridge, and local bone resection was performed under antibiotic treatment. Twenty-four months after the last surgery, wound dehiscence had healed completely without signs of recurrence. Discussion: Osteomyelitis of the jaw in patients treated with tocilizumab has not been reported often. This case confirms the potential role of this interleukin-6 receptor inhibitor in the pathogenesis of MRONJ and shows that patients who receive tocilizumab with MRONJ-like symptoms should be closely monitored. The pathomechanism of MRONJ under tocilizumab therapy remains unclear, so dental practitioners, maxillofacial surgeons, and rheumatologists should look for signs of MRONJ in patients receiving tocilizumab to prevent MRONJ onset.

Eggerthia catenaformis infection originating from a dental abscess causes severe intestinal complications and osteomyelitis of the jaw.

Introduction: Odontogenic foci may result to generalized infections spreading the bacteria through contiguous anatomic cavities or hematogenous spread. The most reported secondary infections caused by oral pathogens are intracranial abscesses. Although, few reports in the literature describe the bacterial spread to extracranial locations. Case description: We describe the case of a 52-year-old male Caucasian patient who was admitted to our hospital suffering from severe sepsis caused by a submandibular abscess. Eggerthia catenaformis was detected in blood and abscess material (confirmed by MALDI-TOF mass spectrometry). The patient subsequently developed a perihepatic abscess and colon perforation, and was stabilized after several surgical interventions. He remained hospitalized for 66 days receiving intravenous antibiotics. Five months later, jaw osteonecrosis with Actinomyces contamination was detected in the left mandible, which also had to be treated surgically. Three years after the last surgery, no signs of recurrence have been detected. Discussion: Oral and maxillofacial surgeons should understand the characteristics of systemic infections, in which the potentially causal intraoral odontogenic foci often lack acute symptoms. If other origins of infection are not detected, elimination of the potentially causal odontogenic foci should be performed. However, the decision making criteria to eliminate suspected causal teeth is needed to be elucidated through more studies.

Evaluation of maxillary sinus anatomy by cone-beam CT prior to sinus floor elevation.

PURPOSE: Surgical complications during sinus floor elevation are frequently caused by septa in the maxillary sinus. In this study, the prevalence of septa was retrospectively determined via three-dimensional imaging to assess the necessity for appropriate imaging prior to sinus floor elevation. MATERIALS AND METHODS: The cone-beam computed tomography scans of 1,029 consecutive patients were evaluated to assess the prevalence of septa, taking into account patient age and sex as well as the number and orientation of septa and their locations. If septa were present, the height was measured and the orientation was determined. RESULTS: Septa were found in 47% of patients and 33.2% of sinuses. There was no statistical difference in prevalence with respect to age, sex, or side. Most patients with septa showed one septum in one sinus (24.6%); 13.7% showed one septum in each sinus. Other combinations (up to three septa per sinus) were found in 8.7% of patients. Septa were most commonly located in the first molar region (256 septa), followed by the second molar region (225 septa), the third molar region (144), second premolar region (136), the first premolar region (44), and the canine region (5). The mean septal height was 11.7 +/- 6.08 mm for septa in a sagittal orientation (n = 206, 25.3%; maximum height of 37 mm) and 7.3 +/- 5.08 mm for those oriented transversely (n = 608, 74.7%; maximum height of 36 mm). The variance was larger for the sagittal orientation group (37.03 mm) than for transversely oriented septa (25.9 mm). CONCLUSION: Septa were found in 47% of the patients in this sample. Appropriate imaging prior to performing sinus surgery seems justified, since complications and the success rate of sinus floor elevation are clearly related to the presence of septa. Int J Oral Maxillofac Implants 2010;25:258-265.

Accuracy of a newly developed integrated system for dental implant planning.

OBJECTIVES: To evaluate the accuracy of the first integrated system for cone-beam CT (CBCT) imaging, dental implant planning and surgical template-aided implant placement. MATERIALS AND METHODS: On the basis of CBCT scans, a total of 54 implant positions were planned for 10 partially edentulous anatomical patient-equivalent models. Surgical guides were ordered from the manufacturer (SICAT). Two different types of guidance were assessed: for assessment of the SICAT system inherent accuracy vendor's titanium sleeves of 2 mm internal diameter and 5 mm length were utilized for pilot drills. The guide sleeves of the NobelGuide system were implemented for fully guided surgery and implant insertion. Deviations perpendicular to the implant axes at the crestal and apical end, as well as the angle deviations between the virtual planning data and the surgical results, were measured utilizing a follow-up CBCT investigation and referential marker-based registration. RESULTS: The SICAT system inherent mean deviation rates for the drilled pilot osteotomies were determined to be smaller than 500 mum even at the apical end. Mean angle deviations of 1.18 degrees were determined. Utilizing the NobelGuide sleeve-in-sleeve system for fully guided implant insertion in combination with the investigated template technology enabled to insert dental implants with the same accuracy. Crestal deviations, in general, were significantly lower than the apical deviations. CONCLUSION: Although hardly comparable due to different study designs and measurement strategies, the investigated SICAT system's inherent accuracy corresponds to the most favourable results for computer-aided surgery systems published so far. In combination with the NobelGuide surgical set for fully guided insertion, the same accuracy level could be maintained for implant positioning.

Comparison of cone-beam imaging with orthopantomography and computerized tomography for assessment in presurgical implant dentistry.

PURPOSE: To establish a basis for weighing the potential diagnostic and therapeutic benefits of three-dimensional cone-beam (CB) data sets in contrast to digital orthopantomography (OPG) and computerized tomography (CT) in implant dentistry. MATERIALS AND METHODS: Twenty-seven patients requiring implant surgery received a single presurgical CB scan. A follow-up digital OPG was taken within a maximal postsurgical period of 2 weeks. For comparison purposes, a control group of 29 patients receiving CT as well as CB diagnosis was analyzed. Image quality of the different modalities was ranked retrospectively by five experienced examiners (from excellent to insufficient) for up to 10 defined criteria, including general image quality and several specific structures. The results were analyzed statistically, and interobserver agreement was calculated using intraclass correlation coefficients (ICCs). RESULTS: The median rating for all investigated criteria was good for CB imaging and between good and insufficient for OPG in the dental implant group. Except for general image quality, statistical analysis showed that CB imaging was significantly superior to OPG imaging for all investigated anatomic structures. With a few exceptions, all investigated anatomic structures in CT and CB imaging were rated excellent in the control group. No significant difference between CT and CB imaging was detected in the control group for all investigated criteria. With a few exceptions, ICCs were higher for CB images than for OPG. In the control group, ICCs for CT and CB images were similar, with a few exceptions. CONCLUSION: The results of the present study confirm superior radiographic visualization for all important high-contrast structures in presurgical implant dentistry assessment for CB imaging in contrast to OPG and a CT-like degree of information for high-contrast structures in CB data sets. Clinically, however, the elevated radiation dosages transmitted by CB imaging must be taken into account.

Vertical ridge augmentation using xenogenous bone blocks: a histomorphometric study in dogs.

PURPOSE: Because vertical ridge augmentation with autogenous bone blocks carries with it a risk of graft resorption and donor site morbidity, the aim of the present study was to compare histologically the healing following vertical ridge augmentation using screwable, xenogenous deproteinized blocks or autologous bone blocks in dogs. MATERIALS AND METHODS: Standardized vertical mandibular defects were surgically created in edentulous ridges of six foxhounds. Two bone blocks (6 x 10 x 15 mm) were inserted on each mandibular side and fixed with both a titanium implant and an osteosynthetic screw. Three different therapies were tested: (1) xenogenous block alone; (2) xenogenous block, covered with a chemically cross-linked collagen membrane; and (3) autologous blocks, harvested during defect preparation. After 3 months of submerged healing, the miniscrews were removed and replaced by dental implants. Following an additional healing period of 3 months, the animals were sacrificed, and dissected blocks were prepared for histomorphometric analysis. RESULTS: During the primary healing period, three of 12 hemimandibles (six blocks) had to be removed because of severe inflammatory reactions (two xenogenous block sites with collagen membrane, one autologous block site). In general, histologic analysis revealed that xenogenous blocks, used alone or combined with a collagen membrane, exhibited osteoconductive properties on a level equivalent to that of autologous blocks, resulting in means of 50% to 60% of ossification of the blocks. Some parts of the xenograft were encased in soft tissue, partly surrounded by multinuclear giant cells. However, all groups showed obvious signs of bone/graft resorption. CONCLUSIONS: Within the limits of the present study, it was concluded that the examined screwable xenogenous bone block might be a useful scaffold for ridge augmentation procedures. However, the combination of xenogenous blocks with a cross-linked collagen membrane did not appear to improve outcomes.

Comparison of torque measurements and clinical handling of various surgical motors.

PURPOSE: Modern implant dentistry requires the application of torque during various treatment steps. This study investigated seven different surgical motors for the accuracy of the applied torque and their reliability. MATERIALS AND METHODS: The following surgical motors were evaluated: Chiropro 980 (Bienair), INTRAsurg 300 and INTRAsurg 500 (KaVo), Osseocare (Nobel Biocare), Surgic XT (NSK), Elcomed SA-200 C (W and H), and Osseo System (XO Dentalcare). The torque was measured during typical surgical and prosthetic procedures using a special load transfer mechanism for a torque gauge. For each setting, 30 measurements were made and means were calculated. RESULTS: The highest percentage shortfall was 20.5% at a set torque of 11.4 Ncm (absolute deviation of -2.4 Ncm). The highest percentage by which a torque was exceeded was 54.6% (absolute deviation of 5.5 Ncm). The lowest value for absolute shortfall was found to be -5.6 Ncm at a set torque of 45 Ncm. The highest absolute exceeded was 15 Ncm at a set torque of 40 Ncm. Potentially problematic torque values were identified in the low-torque-value setting, as the implant position may be changed if a machine driver applies excessive torque to the first-stage healing screw. In addition, in the indication of immediate loading in the high-set-torque group, torque values above the critical value of 50 Ncm may be unwittingly applied while working with a set torque of 40 Ncm. CONCLUSION: For most of the clinically relevant torque settings, precise values were measured, although a few devices delivered potentially problematic torque values for some of the indications.

Remodeling along the bone-screw interface.

OBJECTIVE: The stability of cortical miniscrews depends on the contact between bone and implant. The aim of this study was to compare bone remodeling along the contact surface between the screw and bone with and without pre-drilling. MATERIALS AND METHODS: Twenty-four FAMI miniscrews (length 10 mm, diameter 2 mm) were inserted into the mandibular alveolar process apical to the premolars of four miniature pigs. Each pig received six screws, three on the one side with pre-drilling, three on the other side without pre-drilling. Polychrome fluorescent labels were used to assess the bone remodeling. After 12 weeks of osseointegration, all 24 screws and surrounding bone were removed. Microsections were prepared and analyzed histomorphometrically and under fluorescent microscopy. Differences between the groups were determined using the t test with a significance level of 5%. RESULTS: All the screws osseointegrated without any complications. Those without pre-drilling revealed a bone-screw contact of 64 +/- 11%, and those subjected to pre-drilling 63 +/- 12%. This difference was not significant. The mineral apposition rate, 1.6 +/- 0.4 microm/d and 1.7 +/- 0.4 microm/d, respectively, also failed to demonstrate any significant differences between the groups, while the portion of newly-formed bone in the pre-drilled group was significantly higher (59 +/- 9% vs. 27 +/- 6%). CONCLUSION: Significant differences in the bone-to-screw contact between the two groups are no longer in evidence after three months due to new bone formation. The minor extent of bone remodeling in the not pre-drilled group rules out substantial bone damage, which might have occurred during screw placement as a result of "cracks" or an excessive increase in pressure along the interface. The similar rate of new bone formation in both groups speaks against a stimulating effect of pre-drilling. Despite the absence of quantitative differences, it remains unclear whether the mechanical quality of the newly-formed bone resembles that of preexisting bone. Our findings seem to be applicable to the human mandible, however, its thinner cortical layer means less screw-to-bone contact is likely. We must reckon with less bone contact in the maxilla for the same reason.

Craniomaxillofacial patient-specific CAD/CAM implants based on cone-beam tomography data - A feasibility study.

Customized implants have simplified surgical procedures and have improved patient outcome in craniomaxillofacial surgery. Traditionally, patient-specific data is gathered by conventional computed tomography (CT). However, cone-beam CT (CBCT) can generate a 3D reconstruction of the area of interest with a lower dose of radiation at reduced cost. In this study, we investigated the feasibility of using CBCT data to design and generate customized implants for patients requiring craniomaxillofacial reconstruction. We used CBCT to generate 62 implants for 51 consecutive patients admitted to our department between January 2015 and December 2017. The indications for reconstruction and types of reconstruction were very variable. In all cases, the implants were well fitted and no implant-related complications were detected. Pre-surgical planning was faster and more efficient as we did not have to consult a radiologist. Although CBCT data is more difficult to process than conventional CT data for the implant provider, the clinical advantages are pronounced and we now use CBCT as standard in our department. In conclusion, we have shown that using CBCT to design and manufacture customized implants for reconstruction of the craniomaxillofacial area is feasible and recommend this approach to other departments.

Current concepts in cleft care: A multicenter analysis.

The current surgical techniques used in cleft repair are well established, but different centers use different approaches. To determine the best treatment for patients, a multi-center comparative study is required. In this study, we surveyed all craniofacial departments registered with the German Society of Maxillofacial Surgery to determine which cleft repair techniques are currently in use. Our findings revealed much variation in cleft repair between different centers. Although most centers did use a two-stage approach, the operative techniques and timing of lip and palate closure were different in every center. This shows that a retrospective comparative analysis of patient outcome between the participating centers is not possible and illustrates the need for prospective comparative studies to establish the optimal technique for reconstructive cleft surgery.