Dependence of odontogenic abscess on meteorological parameters: truth or myth?

OBJECTIVES: It is still a common belief among dental practitioners that odontogenic abscesses are somehow linked to meteorological parameters. We investigated the influence of different meteorological parameters on the type of surgical abscess treatment (intra- versus extraoral incision) as a measure of the weather-dependent severity of infection. MATERIALS AND METHODS: In this retrospective cohort study, we analyzed 841 patients who presented at our outpatient clinic with an odontogenic abscess between 2004 and 2013. RESULTS: We found no statistical dependence between intra- versus extraoral abscess incision with regard to temperature, atmospheric pressure, or relative air humidity. The annual distribution of abscesses was even, and the number of abscesses with greater or lesser mean values of each meteorological parameter did not differ significantly. CONCLUSIONS: Our results showed no statistical relationship between meteorological parameters and intra- or extraoral abscess incisions. CLINICAL RELEVANCE: Our analysis supports the assumption that the theorized relationship between odontogenic abscesses and meteorological parameters remains a myth.

Cleft lip and palate: the psychological burden of affected parents during the first three years of their children's lives.

The surgical treatment of cleft lip and palate (CLP) has been well described in the literature. Nevertheless, little is known about the psychological burden of affected parents. The aim of this study was to investigate the psychological burden in parents of children with CLP within the first 3 years of the children's lives. A standardized questionnaire (Parenting Stress Index, PSI) was administered to 33 parents of children with CLP to evaluate their psychological burden. The corresponding interview was conducted independent of any operative procedure during the yearly routine CLP consultation. Each participant's stress profile was assessed and compared with the average values of parents with non-cleft children. Psychological stress was substantially increased in all participants when compared to the parents of healthy children. This result was highly significant (P < 0.001). Parent depression (P < 0.001) and child-related requirements (P < 0.001) were the most critical subscales in the stress profile. Overall, the child-related burden was greater than the parent-related burden. These results indicate that parents of children with CLP have a higher level of psychological stress than parents of non-cleft children. This psychological stress might be reduced if addressed by specialist clinical psychologists in cleft-treating centres.

Reduction in perioperative blood loss using ultrasound-activated scissors during tumour surgery.

The aim of this study was to compare the effectiveness of Harmonic Focus+ scissors with the conventional surgical method regarding surgical blood loss and transfusion of blood products in the surgical treatment of head and neck tumours. In a retrospective study, the intraoperative blood loss, number of units of transfusion products given, operating time, and inpatient length of stay of 74 patients with squamous cell carcinoma were compared. Patients who underwent classic tumour surgery were compared with a group treated with Harmonic Focus+ scissors. A significantly lower intraoperative blood loss (496.15⬰ml vs 1096.0⬰ml, respectively; P⬰=⬰0.002) and shorter operation time (436.89 minutes vs 493.13 minutes, respectively; P⬰=⬰0.030) were achieved using the Harmonic Focus+ scissors when compared to the classic tumour surgery. Additionally, fewer units of blood products needed to be transfused (administration of red cell concentrates, P⬰<⬰0.001) and the length of stay in the intensive care unit was shorter for patients treated with the Harmonic Focus+ scissors (P⬰=⬰0.009). The study results indicate that the use of Harmonic Focus+ scissors during surgery for cancer of the oral cavity and pharynx is a safe and cost-effective method. This is of paramount importance during a pandemic when medical resources are scarce, including access to blood reserves.

[Reconstruction of complex midfacial defects with individualized titanium implants]. / Rekonstruktion komplexer Mittelgesichtsdefekte durch individualisierte Titanimplantate.

BACKGROUND: Loss of hard and soft tissue structures of the midface due to resection or trauma is associated with substancial functional and aesthetic deficits. Besides reconstruction of bony contours for preservation of orbit position and facial symmetry, reconstruction often requires simultaneous transplantation of soft tissue flaps for separation of nasal and oral cavities and refilling of soft tissue volume deficits. PATIENTS AND METHODS: A well-established procedure of our institution will be demonstrated in 10 exemplary patients, in which titanium meshes are customized for individual defect situations using computer-assisted techniques in combination with soft tissue transfer if required. RESULTS: According to our experience, this procedure provides satisfactory results in functional as well as in aesthetic respects. Especially in patients with loss of bony structures of the orbit and preservation of orbital contents, this procedure forms optimal preconditions for prevention of enophthalmos and diplopia by preservation of the original orbital volume. CONCLUSION: Individualized titanium implants should be used more frequently in clinical routine for reconstruction of complex midfacial defects.

[Competence and communication in the implementation of computer-assisted surgical planning]. / Kompetenz und Kommunikation bei der Umsetzung computergestützter chirurgischer Planung.

In the past the planning of surgical interventions in oral and maxillofacial surgery was based on the clinical picture with the assistance of conventional 2­dimensional X­ray images. In cases in which the occlusion was affected, plaster cast models of the jaws were included as a planning aid. With introduction of computed tomography (CT) and the possibility to obtain a 3-dimensional picture of bony structures, it was possible for the first time to construct a virtual image of bony structures and therefore of traumatic, iatrogenic and congenital deformities. Using stereolithographic models, these 3­dimensional relationships were easily "understandable". Risks could be better classified in the planning of an operative intervention and these models could be used as a basis for communication. It was also possible to use the data acquired by CT for design and construction of so-called CAD/CAM patient-specific implants and to implant them; however, the resolution of the data sets and thus the level of detail did not yet correspond to the current standard, so that "delicate" structures could not be constructed. With the improvement of the resolution of CT and the possibility of additive construction processes, such as the selective laser melting (SLM) process or the 3D printing process, the improvement of precision and shaping of the implant practically without limits became reality. Through the bundling of competencies on both sides, engineer and physician, complex computer-aided planning has now become possible. The basis for this is precise communication to avoid errors in the planning process, which in particular needs individual patient information, e.g. about the structure and quality of the overlying soft tissues.

Intraorbital volume augmentation with patient-specific titanium spacers.

INTRODUCTION: Estimating the needed overcorrection of the globe position depends mainly on the clinical evaluation during an operation to correct hypo- and enophthalmos in primary and secondary orbital reconstruction for which several autogenous and alloplastic materials can be used. However, donor-side morbidity and time loss in obtaining autogenous materials are problematic. We developed a novel technique using titanium spacers that minimizes these factors. METHODS: We conducted a retrospective study of all patients treated with titanium spacers for orbital reconstruction at our department between 2014 and 2018. The primary predictor variable was a change in the deformity. The outcome variable was visual appearance, measured on a scale from 0 to 3. Other study variables included binocular vision and complications. Descriptive statistics and the Mann-Whitney rank sum test were used to check for statistical significances. The P-value was set at 0.05. RESULTS: The study sample was composed of 29 patients. Postoperative results were comparable to the results of other methods described in the literature with approximately 25% of our patients experiencing residual visual deformity. The overall visual deformity decreased in our study, and visual appearance improved significantly (P<0.001). Complication rates were also comparable to those reported by other investigators. CONCLUSION: Our method is an effective and safe procedure for correcting hypo- and enophthalmos while minimizing donor-side morbidity and treatment time.

Prelamination of the latissimus dorsi flap for reconstruction in head and neck surgery.

Free microsurgical tissue transfer of the latissimus dorsi flap may be indicated for the restoration of intra- and extraoral defects, especially when a large-sized skin island flap is required. In many cases, use of the latissimus dorsi flap for coverage of large-sized intraoral defects results in bulkiness due to the proportion of subcutaneous fat. Prelamination of free flaps appears to be a promising technique to overcome this flap bulkiness. This modification in flap design could improve the postoperative functional outcome, as well as reduce donor site morbidity. This article presents four novel clinical cases, in which the patients underwent prelamination of the latissimus dorsi flap with local skin grafts during oral cancer treatment in order to reduce the thickness of the free flap and allow tension-free primary closure of the donor site. These attempts successfully covered large-sized intraoral defects, achieving good functional outcomes with minimal donor site morbidity.

Heat-shock protein expression and topical treatment with tacrolimus in oral lichen planus: an immunohistochemical study.

Oral lichen planus (OLP) is a chronic inflammatory mucosal disease of unknown etiology. Usually asymptomatic, the disorder is occasionally complicated by extensive painful erosions. Topical corticosteroids are the mainstay of treatment, but a new topical therapy with tacrolimus has been described previously. The aim of the current study was to examine the expression of heat-shock protein 70 (HSP70) in biopsy specimens from 11 OLP lesions before and after topical treatment with tacrolimus. Immunostaining was performed with anti-HSP70 antibody as the primary layer. Clinically, there was a rapid improvement with topical tacrolimus treatment in 10 out of the 11 patients. The moderate increase in HSP70 expression after treatment with tacrolimus was not significant. It was concluded that topical tacrolimus has no effect on the expression of HSP70 in OLP.

[Selective cervical lymph node dissection for primary, node-negative, oral squamous cell carcinoma: oncologic assessment and clinical relevance of prognostic factors for secondary local metastasis]. / Selektive Halslymphknotenausräumung beim primär klinisch und histopathologisch metastasenfreien Plattenepithelkarzinom der Mundhöhle: Onkologische Wertigkeit und Analyse prognostischer Faktoren und ihrer klinischen Relevanz.

BACKGROUND: The aim of this retrospective study was to evaluate prognostic factors for the development of secondary local lymph node metastases in patients with oral squamous cell carcinoma who had undergone selective neck dissection for primary node-negative disease. PATIENTS AND METHODS: The study included 331 patients with primary squamous cell carcinoma of the oral cavity who underwent 431 selective neck dissections between January 1986 and December 2002 in Germany at the Hannover Medical School's Department of Oral and Maxillofacial Surgery. Several potential prognostic factors were evaluated for their influence on the development of secondary metastases following primary neck dissection. RESULTS: No statistically significant relationship to the appearance of secondary local metastasis following selective neck dissection was detected concerning: patient age or sex, histopathologic tumor stage, primary tumor grade, or adjuvant therapies such as pre- or postoperative radiotherapy and radiochemotherapy. The only study factor with a statistically significant influence was the extent of lymphadenectomy, in which particularly the region of the carotid bifurcation played a decisive role. CONCLUSION: Significantly fewer secondary metastases occurred following neck dissections that included the carotid trigone. In light of these results, we recommend that neck dissection for primary oral squamous cell cancer always include the region of the carotid bifurcation, regardless of the above mentioned associated patient and tumor factors.

In vivo tissue engineered bone versus autologous bone: stability and structure.

This pilot study investigated the biomechanical properties of prefabricated, vascularized bioartificial bone grafts, which may provide an alternative bone source for the restoration of segmental osseous defects. Vascularized bioartificial bone grafts comprise an artificial customized scaffold made of beta-tricalcium phosphate. Bone formation along the prefabricated scaffold is induced by autogenous cancellous bone. Vascularization of the bone graft is provided by the host's vascular system. Within 6 months, a mammalian bioreactor (sheep were used in the present study) creates heterotopic vascularized bioartificial bone grafts of a predetermined anatomical shape, which can be harvested for reconstructing osseous defects. The bioartificial bone grafts in this study contained up to 25% bone tissue, as shown by histomorphometric analysis and computed tomography. Moreover, unconfined compression tests revealed that the constructs had mechanical characteristics similar to those of ovine cancellous bone. Therefore, this method could be applied to generate vascularized prefabricated bone substitutes for critical-size defects.

Piezoelectric surgery and navigation: a safe approach for complex cases of Eagle syndrome.

Eagle syndrome was first described by Eagle in 1937. It is associated with an elongated styloid process and/or calcification of the stylohyoid ligament, mainly resulting in pain in the orofacial region. The treatment of Eagle syndrome includes conservative treatment with physical therapy supported by medication, or surgical removal of the styloid process. Two different surgical approaches are described in the literature: the transoral and transcervical approaches. Both have their limitations and specific intraoperative risks. A modification of the transcervical approach that adds an extra security measure to the treatment of complex cases of Eagle syndrome is presented herein. The styloid process was removed by combining piezoelectric surgery, preoperative digital planning, and surgical navigation. No complication was noted, and the patient recovered quickly after surgery. A follow-up visit 2 months later showed no remaining symptoms of Eagle syndrome on the treated side. Therefore, digital planning and surgical navigation could add valuable safety measures to the treatment of complex cases of Eagle syndrome.

En bloc prefabrication of vascularized bioartificial bone grafts in sheep and complete workflow for custom-made transplants.

The aim of this pilot study was to determine, in a new experimental model, whether complex bioartificial monoblocs of relevant size and stability can be prefabricated in a defined three-dimensional design, in which the latissimus dorsi muscle serves as a natural bioreactor and the thoracodorsal vessel tree is prepared for axial construct perfusion. Eighteen sheep were included in the study, with six animals in each of three experimental groups. Vitalization of the ß-tricalcium phosphate-based constructs was performed by direct application of unmodified osteogenic material from the iliac crest (group A), in vivo application of nucleated cell concentrate (NCC) from bone marrow aspirate (group B), and in vitro cultivation of bone marrow stromal cells (BMSC) in a perfusion bioreactor system (group C). The contours of the constructs were designed digitally and transferred onto the bioartificial bone grafts using a titanium cage, which was bent over a stereolithographic model of the defined subvolume intraoperatively. At the end of the prefabrication process, only the axial vascularized constructs of group A demonstrated vital bone formation with considerable stability. In groups B and C, the applied techniques were not able to induce ectopic bone formation. The presented computer-assisted workflow allows the prefabrication of custom-made bioartificial transplants.

Elongated coronoid process: CT-based quantitative analysis of the coronoid process and review of literature.

Impingement of the enlarged coronoid processes against the medial surfaces of the zygomatic arches and posterior surfaces of the body of the zygomatic bones results in mechanical restriction of the mouth opening. The authors introduce a helpful tool for easy assessment and estimatation of the length of the coronoid process, measured on the CT scans of 40 patients (20 adults, 20 adolescents) and report a case of a 13-year-old boy suffering from restricted mouth opening caused by bilateral hyperplasia of the coronoid process. The CT based analysis resulted in a mean length of the coronoid process of 13.02mm in adults and 12.43mm in adolescents. The 13-year-old boy had a length of nearly 2cm. For comparison, a coronoid/condyle ratio was developed. This ratio showed a value of 0.78 for all patients compared with a value of about 2.0 for the boy. The literature review revealed comparable results to the reported case. Most of the patients were adolescent, male and presented a median history of 2 years until correct diagnosis.

Prefabrication of vascularized bioartificial bone grafts in vivo for segmental mandibular reconstruction: experimental pilot study in sheep and first clinical application.

The key elements for bioartificial bone formation in 3D matrices are large numbers of osteogenic cells and supplies of oxygen and nutrition. Vascularization becomes more important with the increasing size and complexity of seeded scaffolds required for clinical application in reconstructive craniomaxillofacial surgery. Prefabrication of vascularized bioartificial bone grafts in vivo might be an alternative to in vitro tissue engineering techniques. Two cylindrical beta-TCP-scaffolds (25 mm long) were intraoperatively filled with autogenous bone marrow from the iliac crest for cell loading and implanted into the latissimus dorsi muscle in 12 sheep. To determine the effect of axial perfusion, one scaffold in each sheep was surgically supplied with a central vascular bundle. Sheep were killed 3 months after surgery. Histomorphometric analysis showed autogenous bone marrow from the iliac crest was an effective source of osteogenic cells and growth factors, inducing considerable ectopic bone growth in all implanted scaffolds. Bone growth, ceramic resorption and angiogenesis increased significantly with axial perfusion. The results encourage the application of prefabricated bioartificial bone for segmental mandibular reconstruction in man. In clinical practice, vascularized bioartificial bone grafts could change the principles of bone transplantation with minimal donor site morbidity and no shape or volume limitations.

Surface quality achieved by polishing and by varnishing of temporary crown and fixed partial denture resins.

STATEMENT OF PROBLEM: Studies have suggested that coating a temporary restoration with varnish material could replace time-consuming polishing procedures needed for achieving an optimally smooth surface. PURPOSE: This study examined the surface roughness of acrylic resins after having been polished or coated with different varnish materials. MATERIAL AND METHODS: A total of 360 cylindrical specimens were fabricated from 9 brands of resin. One surface on each specimen was machined flat and subsequently either polished with rubber polishers or coated with 1 of 9 varnishes. Selected specimens were subjected to thermal cycling (5 degrees C to 55 degrees C, 2000 cycles). Surface quality was assessed by means of a profilometer and by SEM examination. RESULTS: Polished specimens had average surface roughness values (Ra) of 0.8 microm; differences in roughness between materials were small, but statistically significant. Type of coating had a significant influence on surface quality. Depending on the combination of materials used, the coating produced both smoother and rougher surfaces than polishing (0.4 microm < Ra < 4.6 microm). Five coatings were deemed not to be clinically applicable because of poor wetting properties. Thermal cycling did not significantly influence surface quality, but caused minute cracks in the cyanoacrylate coating. CONCLUSION: In regard to surface quality and applicability, the use of varnishes on temporary restorations is not advisable.