The Manifestations of Covid-19 Infection. Manifestations in Patients with Temporomandibular Joint Disorders

The authors present a group of patients who were treated for exacerbation of temporomandibular joint disorders (TMD) following Covid-19 infection and who in the past had successfully undergone surgery of the temporomandibular joint (TMJ). The group consisted in total of 21 patients who relapsed after contracting Covid-19. There were 4 men and 17 women, the average age was 45.6 years (28-63). The most common complaint was pain. In all cases, the pain was located in the preauricular area, 4 patients had pain in the lateral side of the neck, 1 patient had pain of the nasal alae. During clinical examination, pain was present on palpation of the masseter muscle (19 patients), temporal muscle (4 patients) and the TMJ area (4 patients). In 4 cases, pain on palpation was present in the area of the nape and sternocleidomastoid muscles. Treatment in all cases was the same: thermotherapy, muscle relaxation massage and non-steroidal anti-inflammatory drugs. Symptoms subsided in all cases within 2 weeks. In light of the Covid-19 pandemic, it is also necessary to expect an increased number of patients with TMD. The authors recommend targeted patient histories regarding Covid-19 infection when examining patients with TMD symptoms - this will certainly facilitate determining the etiology of the pain.

Evaluating the Effect of Conservative Therapy in Patients with Wilkes Stage III Temporomandibular Joint Derangement

The authors evaluated effects of physiotherapy in patients experiencing Wilkes III temporomandibular joint (TMJ) derangement with clinically limited joint mobility, but no pain. The group consisted of 31 patients with unilateral temporomandibular joint involvement, 3 men and 28 women (average age was 30.93, ranging from age 12 to 61). None of the patients in the group had experienced any previous TMJ therapy. The patients underwent conservative therapy in the form of home exercise (mobilisation and isometric exercises) as the first step in treatment. The authors evaluated the improvement in jaw movement (maximal interincisal opening - MIO) and the patients' subjective assessments of their condition. Disc position before and after two months of exercise was also evaluated using ultrasound examination. The average MIO value in patients before starting the exercises was 33.5 mm, and after two months of exercises, 42.4 mm. Subjective assessment by patients: 26 patients (83%) described their condition as completely satisfactory, not requiring further therapy. Of these patients, ultrasound examination showed 10 patients with complete disc reduction, 9 patients with a change in disc displacement with reduction, and 7 patients with a continuing (unchanged) state of disc displacement. Results of our study show the effect of conservative therapy in patients with painless TMJ due to disc displacement (WIII). Effect of home exercises which were easy to perform, simple and acceptable to the patient were demonstrated.

A Complex Evaluation of the In-Vivo Biocompatibility and Degradation of an Extruded ZnMgSr Absorbable Alloy Implanted into Rabbit Bones for 360 Days

The increasing incidence of trauma in medicine brings with it new demands on the materials used for the surgical treatment of bone fractures. Titanium, its alloys, and steel are used worldwide in the treatment of skeletal injuries. These metallic materials, although inert, are often removed after the injured bone has healed. The second-stage procedure—the removal of the plates and screws—can overwhelm patients and overload healthcare systems. The development of suitable absorbable metallic materials would help us to overcome these issues. In this experimental study, we analyzed an extruded Zn-0.8Mg-0.2Sr (wt.%) alloy on a rabbit model. From this alloy we developed screws which were implanted into the rabbit tibia. After 120, 240, and 360 days, we tested the toxicity at the site of implantation and also within the vital organs: the liver, kidneys, and brain. The results were compared with a control group, implanted with a Ti-based screw and sacrificed after 360 days. The samples were analyzed using X-ray, micro-CT, and a scanning electron microscope. Chemical analysis revealed only small concentrations of zinc, strontium, and magnesium in the liver, kidneys, and brain. Histologically, the alloy was verified to possess very good biocompatibility after 360 days, without any signs of toxicity at the site of implantation. We did not observe raised levels of Sr, Zn, or Mg in any of the vital organs when compared with the Ti group at 360 days. The material was found to slowly degrade in vivo, forming solid corrosion products on its surface.

Zn-0.8Mg-0.2Sr (wt.%) Absorbable Screws-An In-Vivo Biocompatibility and Degradation Pilot Study on a Rabbit Model

In this pilot study, we investigated the biocompatibility and degradation rate of an extruded Zn-0.8Mg-0.2Sr (wt.%) alloy on a rabbit model. An alloy screw was implanted into one of the tibiae of New Zealand White rabbits. After 120 days, the animals were euthanized. Evaluation included clinical assessment, microCT, histological examination of implants, analyses of the adjacent bone, and assessment of zinc, magnesium, and strontium in vital organs (liver, kidneys, brain). The bone sections with the implanted screw were examined via scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS). This method showed that the implant was covered by a thin layer of phosphate-based solid corrosion products with a thickness ranging between 4 and 5 µm. Only negligible changes of the implant volume and area were observed. The degradation was not connected with gas evolution. The screws were fibrointegrated, partially osseointegrated histologically. We observed no inflammatory reaction or bone resorption. Periosteal apposition and formation of new bone with a regular structure were frequently observed near the implant surface. The histological evaluation of the liver, kidneys, and brain showed no toxic changes. The levels of Zn, Mg, and Sr after 120 days in the liver, kidneys, and brain did not exceed the reference values for these elements. The alloy was safe, biocompatible, and well-tolerated.

Does arthroscopic lysis and lavage in subjects with Wilkes III internal derangement reduce pain?

PURPOSE

The aim of this study was to determine the efficacy of arthroscopic lysis and lavage on pain in patients with unilateral Wilkes stage III derangement of the temporomandibular joint. Authors retrospectively evaluated whether the arthroscopic lysis and lavage has an impact on pain decrease in patients with moderate osteoarthritis.

METHODS

Patients with unilateral Wilkes III of temporomandibular joint were included in this study. All patients underwent arthroscopic lysis and lavage (ASC-L), assessed pain before and after the procedure (primary outcome variable), maximal interincisal opening (MIO) was recorded as secondary outcome variable. The patients also subjectively assessed whether they were satisfied with the outcome of the arthroscopy or whether their condition required further interventions. The disc position was evaluated by magnetic resonance imaging (MRI) 24 months after the arthroscopy and compared with the disc position on the MRI prior to the arthroscopy. The R Project for Statistical Computing 3.4.1 and the Gretl Pro programs were used for statistical analysis. In addition to the descriptive statistics methods, the Shapiro-Wilk normality test was used to verify data normality and the two sample t test used to test the hypotheses themselves.

RESULTS

The sample consisted of 62 patients who underwent arthroscopic lysis and lavage (ASC-L) in 2015 and 2016. It included 6 men and 56 women with an average age of 34.37. Pain and MIO were recorded during regular check-ups 1, 3, 6, 12, and 24 months. A therapeutic effect (MIO over 34 mm, VAS score 0-1) was recorded in 69% of cases 24 months after the ASC-L. Nonetheless, the work demonstrated the importance of subjective assessment, as 87% of patients perceived their condition as satisfactory after 24 months and not requiring further intervention, while 8 patients (13%) perceived it as unsatisfactory. Disc reposition 24 months following the ASC-L was recorded in only 44% of patients who assessed their condition as satisfactory. Patients with persistent disc dislocation 24 months after the arthroscopy were older, had a lower average maximal interincisal opening value before the ASC-L and a longer duration of mandibular movement restriction before the ASC-L (evaluated as a statistically significant difference).

CONCLUSION

In this study, the authors confirmed that ASC-L is an effective therapeutic method in patients with WIII, from both clinical and subjective perspectives. This work demonstrated that improvement in patients with Wilkes stage III is not related to disc reposition. Postoperative physiotherapy is an integral component of ASC-L and is reflected in the final results.

Discectomy with Subsequent Free Fat Flap Insertion in Disc Perforation Therapy of Temporomandibular Joint. Assessment of Results 24 Months after Operation

Discectomy with replacement of disc is one possibility for treating disc perforation where conservative, mini-invasive therapy and arthroscopy has had no effect. Allogenic or autologous materials are used to replace the disc. The authors assess the use of a free fat flap (FFF) in 19 patients who in 2015-2016 underwent a unilateral discectomy with disc replacement. In the retrospective 24-month follow-up study a total of 16 patients (84%) were free of difficulties. 24 months after the operation mouth opening was on average 39.3 mm, pain (VAS - visual analog scale (0-10) was assessed on average at 0.3). Crepitus was present after 24 months in 37.5% of patients (6 patients). An assessment of changes in joint structures on cone beam computed tomography (CBCT) for these patients 24 months after the operation showed the progression of flattening of the joint head, in one case unevenness of the joint head. In 3 cases (16%) there was a recurrence of the state within 24 months - in all cases with clinical manifestations of pain and limited mobility, for these patients on the CBCT significant unevennesses of the joint head, subchondral cysts were noted. The authors find discectomy with use of FFF to be an effective method of treatment with a minimum of complications. However, one should take into account the relatively short time of monitoring after the operation (2 years) and limited number of patients in the cohort (19 patients).

A new look at transudation: the apocrine connection

Transcellular trafficking in which various molecules are transported across the interior of a cell, is commonly classified as transcytosis. However, historically this term has been used synonymously with transudation. In both cases transcellular trafficking starts with the internalization of proteins or other compounds on the basal or basolateral side of a cell and continues by their transport across the interior to the apical pole (or vice versa) where they are subsequently released. This allows a cell to release products which are synthesized elsewhere. Here, we discuss the common features of both transcytosis and transudation, and that which differentiates them. It appears that transcytosis and transudation are identical in terms of vesicular import and endosomal sorting of cargo, but completely differ in the re-secretion process. Specialized epithelial cells re-release substantial quantities of the endocytosed material, and often also a great variety. Some recent studies indicate that this is achieved by non-canonical apocrine secretion rather than by the regular vesicular mechanism of exocytosis, and takes place only on the apical pole. This massive re-release of endocytosed proteins, and potentially other compounds via the apocrine mechanism should be considered as transudation, distinct from transcytosis.