The Incidence of Dental Needs During Isolated Missions Compared to Non-isolated Missions: A Systematic Review and Implications for Future Prevention Strategies

INTRODUCTION

Dental emergencies in isolated groups have always been difficult to treat. Especially in people or groups who cannot be evacuated and who need urgent dental assistance: long-term submarine missions, long-term spaceship trips, military or non-governmental organizations deployments in conflict areas, military maneuvers, etc. The dental and evacuation problems could put the success of the mission at risk, with relevant associated economic and strategic costs. Our study summarizes current evidence about dental problems in isolated personnel (submarines and Antarctic missions) compared to other non-isolation conditions (military deployment in conflict area, military maneuvers) with the objective to assess the need for specific dental equipment in special long-term isolation conditions.

MATERIALS AND METHODS

We searched Medline, Cochrane Library, and Dentalgate between 1960 and 2017 for studies reporting dental disease in long-term isolation conditions (minimum 1 month) versus non-isolation conditions. We conducted the systematic review with all studies fitting the inclusion criteria. The comparison of the incidence rate was performed fitting a Poisson regression model to see the effect of the individual's condition on the incidence of dental event.

RESULTS

Thirty-eight studies were included in the systematic review. Antarctic missions showed a higher dental incidence rate compared to non-isolation conditions, but submarine missions showed the lowest dental incidence rate. In the sub-analysis of acute dental events, those with great impact on unit effectiveness, the incidence rates were higher. Caries and secondary decay events were the most prevalent dental problem in all conditions, followed by periodontal pathology and fractures of teeth or tooth problems not due to tooth decay in isolation conditions, and then by molar problems and endodontic problems in non-isolation conditions. The most common acute dental events were third molar problems and endodontic problems in all conditions.

CONCLUSION

This systematic review shows that the incidence of dental pathology in long-term isolation conditions may seem relatively infrequent but it exists and is relevant. Dental events are unpredictable, unrelated to trauma, and caused mainly by poor dental status. Preventive measures considerably reduce dental prevalence.

The lateral ankle ligaments are interconnected: the medial connecting fibres between the anterior talofibular, calcaneofibular and posterior talofibular ligaments

PURPOSE

A deep knowledge of lateral ankle ligaments is necessary to understand its function, pathophysiology and treatment options. The ankle lateral collateral ligament is formed by the anterior talofibular ligament (ATFL), the calcaneofibular (CFL) and the posterior talofibular ligament (PTFL). Although previous studies have reported connections between these ligaments on its lateral side, no studies have specifically assessed connections on the medial side. The aim of this study was to assess the morphology and consistency of the medial connections between the components of the lateral collateral ligament complex of the ankle.

METHODS

Forty fresh-frozen ankle specimens were dissected to look for connections between the three lateral ankle ligaments. After visualization of the lateral ligaments was achieved, the fibula was amputated and ligament insertions were released at the talar and calcaneal insertion points. Observation of the connections and video analysis of the dynamic relationships of ligament connections were performed.

RESULTS

Connections were found in all cases between the ATFL and PTFL, the ATFL and CFL, and the CFL and PTFL. Connections between ATFL and PTFL were not homogeneous. Although connections between the ATFLif and PTFL were noted in all cases (40), only 17 ankles (42.5%) had connections between the ATFLsf and PTFL. The amount of fibres of connection was also variable.

CONCLUSION

Connections between the three components of the lateral collateral ligament of the ankle may be observed from the medial aspect of the ankle, and this may have important implications for arthroscopic lateral ligament repair.

The anterior tibiofibular ligament has a constant distal fascicle that contacts the anterolateral part of the talus

PURPOSE

The anterior tibiofibular ligament (ATiFL) and its distal fascicle have been the subject of numerous studies, mainly due to the involvement of this ligament in anterolateral soft-tissue impingement of the ankle. There is currently no firm evidence related to the incidence of the distal fascicle or the frequency with which it is in contact with the talus, or whether this is a constant anatomic finding. In addition, the terminology used to refer to this structure is not accurate and varies widely in previous studies. The purpose of this study was to perform an anatomic study on a large number of specimens to clarify the anatomy of the anterior tibiofibular ligament, and specifically its distal fascicle, and its possible role in anterior ankle impingement syndrome.

METHODS

During a 7-year period (2010-2016), cadaveric ankle specimens dissected at our Anatomy Department were included in this study, accounting for a total of 154 ankles. The incidence of the distal fascicle and its contact with the talus were documented.

RESULTS

One hundred and seventeen ankles were included [78 men, 39 women, with a median age of 79.3 years (range 51-100 years)]. The ATiFL was found to have a distal fascicle in 100% of ankles, contacting the anterolateral part of the talus in all cases. The contact was increased in plantarflexion and reduced in dorsiflexion and finally disappeared completely in maximum dorsiflexion.

CONCLUSIONS

The ATiFL has a constant distal fascicle that is in contact with the talus in the neutral position and in plantar flexion. Contact disappears in maximum dorsiflexion.

X-shaped inferior extensor retinaculum and its doubtful use in the Bröstrom-Gould procedure

PURPOSE

The inferior extensor retinaculum (IER) is an aponeurotic structure located in the anterior aspect of the ankle. According to the literature, it can be used to reinforce a repair of the anterior talofibular ligament in ankle instability. Despite its usual description as an Y-shaped structure, it is still unclear which part of the retinaculum is used for this purpose, or if it is instead the crural fascia that is being used. The purpose of this study is to define the anatomical characteristics of the IER to better understand its role in the Broström-Gould procedure.

METHODS

Twenty-one ankles were dissected. The morphology of the IER and its relationship with neighbouring structures were recorded.

RESULTS

Seventeen (81%) of the IER in this study had an X-shaped morphology, with the presence of an additional oblique superolateral band. This band, by far the thinnest of the retinaculum, is supposed to be used to reinforce the repair of the anterior talofibular ligament. The intermediate dorsal cutaneous nerve (lateral branch of the superficial peroneal nerve) was found to cross the retinaculum in all cases.

CONCLUSIONS

The IER is most commonly seen as an X-shaped structure, but the fact that the oblique superolateral band is a thin band of tissue probably indicates that it may not add significant strength to ankle stability. Furthermore, the close relationship of the retinaculum with the superficial peroneal nerve is another factor to consider before deciding to perform a Broström-Gould procedure. These anatomical findings advise against the use of the Gould augmentation.

External Cervical Resorption: A New Oral Manifestation of Systemic Sclerosis

Systemic sclerosis (SSc) is a complex, chronic, and progressive autoimmune disease. SSc causes bone resorption of mandible and distal phalanges of fingers through a known mechanism, and it has also been pointed out as a possible cause of apical root resorption of teeth, because tooth resorption is regulated by similar mechanisms to those controlling bone resorption. The objective of this article was to report the first case in the literature of external cervical resorption (ECR) as an oral manifestation of SSc. A 66-year-old female patient with a 35-year history of SSc was diagnosed with multiple ECRs through a computerized axial tomography and clinical examination. All known causes of ECR were discarded after a detailed anamnesis and clinical examination. This report details SSc as a possible cause of ECR and discusses the pathogenesis of ECR in relation with SSc. The systemic alterations provoked by SSc can be related to the etiopathogenesis of cervical root resorption. It is extremely relevant that dental care providers be aware that external cervical resorptions could be present in patients suffering from SSc, consciously look for these lesions, treat them early in case they are present, and advise the patient with SSc of the importance of continuous dental controls.

Perception of dental aesthetics in paediatric dentistry

AIM

Assessing the perception of the aesthetic components of the oral health by paediatric patients at different stages of the child psychological development of Piaget.

MATERIALS AND METHODS

Twenty children aged between 21 months and 11 years, of both sexes, patients of a private clinic, were selected. The present study group consisted of patients treated for oral pathologies. A set of similar supplies was given to all children and they were asked to do a drawing, whose theme was "beautiful teeth and ugly teeth". The drawings were evaluated according to the classification of the cognitive development of Piaget.

RESULTS

Children of all ages clearly represent their perception of what "beautiful teeth" and "ugly teeth" are. These representations provide the dental professional a clear vision of the child's feeling about dental aesthetics.

CONCLUSION

The drawings are a useful source of information for assessing the aesthetic perception of paediatric patients. The knowledge of the children's aesthetic perception is relevant to paediatric dentists because children are conscious about their dental aesthetic appearance and that of the other children.

Immunohistochemical identification of TGF-beta1 at the maxillaries in growing Sprague-Dawley rats and after muscle section

Growth factors are currently being extensively studied in the literature to ascertain their role during maxillofacial development. Taking into account that few investigations refer to the functions of growth in the maxillaries, our aim was to identify the TGF-beta1 immunohistochemical expression pattern in the maxillaries of growing rats. A secondary aim was to identify this pattern after orofacial function inhibition by muscle section. In the palate and the mandibular symphysis and body, we found that bone was formed through an endomembranous pathway with intense TGF-beta1 staining inside chondroid cells during the maximum development stages. At the midpalatal suture and the mandibular symphysis and condyle, endochondral ossification was detected with an intense expression of TGF-beta1 inside the chondrocytes when major growth occurred. After the muscle had been sectioned, at the mandible the maturation process was accelerated, this change being transitory until muscular function was recovered. However, at the palate, the intervention caused a greater disturbance of the growing pattern, which did not recover normality.

BS-SEM evaluation of the tissular interactions between cortical bone and calcium-phosphate covered titanium implants

The improvement of the reliability of the contact between the osseous tissues and the implant materials has been tested by recovering the metallic implants with ceramic materials, usually calcium phosphates. In our study, the calcium phosphate recovering layers were deposited by means of a pulsed-laser deposition technique. Our aim was to to evaluate the tissue interactions established between cortical bone and titanium implants covered by five different layers, ranging from amorphous calcium phosphate to crystalline hydroxyapatite, obtained by altering the parameters of the laser ablation process. The surgical protocol of the study consisted in the simultaneous implantation of the five types of implants in both the tibial dyaphisis of three Beagle dogs, sacrificed respectively one, two and three months after the last surgical procedures. After the sacrifice, the samples were submitted to a scheduled procedure of embedding in plastic polymers without prior decalcification, in order to perform the ultrastructural studies: scanning microscopy with secondary and backscattered electrons (BS-SEM). Our observations show that both in terms of the calcified tissues appearing as a response to the presence of the different coatings and of time of recovering, the implants coated with crystalline calcium phosphate layers by laser ablation present a better result than the amorphous-calcium-phosphate-coated implants. Moreover, the constant presence of chondroid tissue, related with the mechanical induction by forces applied on the recovering area, strongly suggests that the mechanisms implied in osteointegration are related to endomembranous, rather than endochondral ossification processes.

Back-scattered electron imaging of a non-vertebral case of hypervitaminosis A in a cat

We describe a clinical case of hypervitaminosis A in a cat. The main lesions were bony fusions of both the hip and stifle joints, without spinal involvement. A post-mortem study using back-scattered scanning electron microscopy (BEI-SEM) revealed that exostoses had formed around the joints without articular surface involvement. The more recently formed areas of bony proliferation were composed mainly of chondroid tissue surrounded by different degrees of woven bone. As the bony reaction occurred, remodelling of the trabeculae was observed which lead to progressive substitution of chondroid tissue by woven bone surrounded by apposition of lamellar bone. No traces of calcified cartilage were observed in any of the bone sections evaluated.

Skeletal growth and chondroid tissue

Membranous and endochondral ossification processes are insufficient to describe all the aspects observed in the growing skeleton. The presence of chondroid tissue that we have identified by means of all modern histological techniques, including those able to detect the different types of collagen, has also to be explained. Present in the mandibular symphysis of either the human or cat fetuses, chondroid tissue has also been observed in the other parts of the mandible, in the sutural areas of the skull and in all the bones of both axial and appendicular skeleton. The differentiation of the mesenchyme into chondroid tissue could probably be related with mechanical forces exerted simultaneously in opposite directions or with a transient ischemia.

Metopic sutural closure in the human skull

The present study reveals the presence in the sutural area of secondary cartilage, assuring the passive growth of the bones and undergoing an endochondral ossification, but without playing a direct role in the synostosis. The chondroid tissue is responsible for the growth of each frontal bone towards the other and constitutes the first bridge of union between the two bones. It is the most important finding in this study, which provides a description of the closure of the metopic suture and of the maintenance of an open sutural space by a process of active resorption. This new knowledge will help to understand better the whole process of suture closure and its pathology.

Calcified tissues involved in the ontogenesis of the human cranial vault

The cranial vault of fifteen human subjects varying in age from 20th week of gestational life to 9th month post-matum were submitted to microradiographic and histological analysis. Different phenomena such as cortical drift, bone cavitation and progressive substitution of different calcified tissues by lamellar bone are illustrated. Moreover, this study reveals in several areas the presence of chondroid tissue; it constitutes the edges of the sutures and is responsible for their growth till the post-natal period. Therefore, it can be supported that the role of chondroid tissue is essential for the harmonious development of the cranial vault.