Uncommon sublingual ulceration in an infant

Sir, An eight-month-old girl was referred to our department with an extensive lingual ulceration. The parents noted that she had habitually bitten her tongue since the release of her first teeth at the age of six months. She was a poor feeder and did not sleep well because of the painful lingual ulceration. There was no family history of developmental disorders or congenital syndromes. Intraoral examination revealed a deep, circular, and extensive ulceration of the whole ventral surface of the tongue with intermittent bleeding in the tongue (Figs. 1a – c). An examination of the rest of the intraoral mucosa revealed that the lower central incisors had recently erupted. However, there were two other ulcerations of the palmar surface of the second and third fingers caused by nocturnal finger biting. Neurological examination noted a lack of pain sensitivity related to peripheral neuropathy diagnosed as congenital insensitivity to pain. Based on the clinical features and the particular site on the ventral surface of the tongue against the lower central incisors and ulcerative lesions of the fingers due to self-biting, the lesion was diagnosed as Riga–Fede disease. Because of the size of the ulceration, significant pain during feeding led to inadequate nutrient intake associated with permanent sleep disturbances. Radical treatment was chosen and the lower central incisors were extracted. Topical corticosteroids were prescribed to help with healing. The term Riga–Fede disease has been used to describe a traumatic ulceration that has occurred on the ventral surface of the tongue in newborn babies and infants. It is most commonly related to neonatal or natal teeth but may also occur in infants after the eruption of the primary lower incisors [1]. This benign ulceration occurs as a result of repetitive mechanical trauma caused to the oral mucosal surfaces by the teeth and is most commonly located on the ventral surface of the tongue against the teeth [1,2]. Riga–Fede disease may reveal an underlying developmental or neurologic disorder, including congenital insensitivities to pain [3]. The case of our patient was associated with congenital insensitivity to pain. Failure to diagnose may lead to dehydration and inadequate nutrient intake in the infant because of the significant pain during feeding. No biopsy is needed. The diagnosis of Riga–Fede disease is based on clinical characteristics [1,2]. Treatment should focus on eliminating the source of trauma. Conservative treatment is attempted at first by grinding the sharp edges of the teeth and placing composite resin in a dome shape or by placing a protective ring. If conservative treatment fails to heal the wounds, radical treatment may be necessary, such as extraction of the teeth [2,3]. We believe that Riga–Fede disease must be recognized by clinicians to avoid misdiagnosis and delayed treatment.

Histomorphometrical study of the tongue epithelium of the peregrine falcon (Falco peregrinus)

The aim of this study is to examine the dorsal lingual epithelium of the peregrine falcon (Falco peregrinus) of the family Falconidae. The tongue in its dorsal, lateral and ventral surfaces is covered with a non-keratinized multilayered stratified squamous epithelium. Lamina propria is present beneath the epithelial layers. Morphometrically, thickness of the apex tongue epithelium is more than that in the tongue body. Thickness of the ventral surface of the tongue is less than that in the dorsal one. Thickness of the lateral surface of the tongue was thicker than that in the ventral one and tongue body. Large and small conical papillae appeared on the posterior dorsal surface of the lingual body. There are lingual glands in certain areas of tongue body with numerous openings through the dorsal surface.

Geographic Stomatitis with Multiple Areas Involvement of Oral Cavity: A Case Report and Review of Literatures

Background: Geographic stomatitis is an uncommon migratory benign lesion of oral mucosa with unknown etiology. It can affect all the areas of the oral mucosa, but the dorsum and lateral borders of the tongue are the most commonly involved areas called geographic tongue. The clinical appearance of this condition is the oval or circular erythematous areas with irregular elevated keratotic borders. These characteristic features of geographic stomatitis are diagnostic for all clinicians when appearing on the dorsum of the tongue, despite other affected areas of oral mucosa that can confuse clinicians. This condition may be associated with some diseases such as psoriasis, Reiter’s syndrome, and atopic conditions, so the clinicians should rule out these diseases and diagnose the geographic stomatitis. Case Report: A 17-year-old male attended to our department for a routine dentistry checkup. During the intraoral examination, we found multiple erythematous areas surrounded by a thin white border on different surfaces of his oral cavity. His extraoral examinations were completely normal. Conclusion: Due to the rarity of this lesion on the other sites of oral mucosa rather than dorsum and lateral borders of the tongue such as labial mucosa, buccal mucosa, the floor of the mouth, ventral surface of the tongue, and palate, it is necessary to report, study and evaluate each case of this condition that clinicopathologic findings have confirmed this diagnosis, to treat and advice these patients on the best approach. [GMJ.2021;10:e2071]

New species of bristletails of the family Machilidae (Archaeognatha) from Kazakhstan

The fauna of bristletails of the family Machilidae in Kazakhstan currently includes one species of the genus Silvestrichiloides Mendes, 1990 and 13 species of the genus Allopsontus Silvestri, 1911. The present study describes one new species of the genus Silvestrichiloides (S. berkarensis Kaplin, sp. nov. from South Kazakhstan) and two new species of the genus Allopsontus (A. (Kaplinilis) nigrostriatus Kaplin, sp. nov. and A. (Machilanus) perfectus Kaplin, sp. nov. from Southeastern Kazakhstan). Silvestrichiloides berkarensis sp. nov. differs from the other species of this genus in the structure of antennal flagellum, apical palpomere of labial palp and ovipositor. Among species of the subgenus Kaplinilis Mendes, 1990, A. nigrostriatus sp. nov. belongs to a group of species characterized by numerous short chaetae on the ventral surface of the 5–7th palpomeres of the male maxillary palp and by the absence on the labial palp. This group includes two species: A. volgensis Kaplin, 1999 from Samara Region and A. smelyanskii Kaplin, 1999 from Orenbourg Region (both Russia). The new species differs from A. volgensis and A. smelyanskii in the length of the body and antenna, color of scales on the upper surface of the body, shape of the compound eye and paired ocellus, structure of the flagellum and apical palpomere of the male labial palp. The subgenus Machilanus Silvestri, 1934 is represented only by A. bitschi Wygodzinsky, 1962 from Afghanistan and A. perfectus sp. nov., which are characterized by numerous short chaetae on the ventral surface of the 2nd–7th palpomeres of the male maxillary palp. Allopsontus perfectus sp. nov. differs from A. bitschi in the shape of compound eyes, paired ocellus, structure of male labial palp and genitalia.

Extreme suction attachment performance from specialised insects living in mountain streams (Diptera: Blephariceridae)

Suction is widely used by animals for strong controllable underwater adhesion but is less well understood than adhesion of terrestrial climbing animals. Here we investigate the attachment of aquatic insect larvae (Blephariceridae), which cling to rocks in torrential streams using the only known muscle-actuated suction organs in insects. We measured their attachment forces on well-defined rough substrates and found that their adhesion was less reduced by micro-roughness than that of terrestrial climbing insects. In vivo visualisation of the suction organs in contact with microstructured substrates revealed that they can mould around large asperities to form a seal. We have shown that the ventral surface of the suction disc is covered by dense arrays of microtrichia, which are stiff spine-like cuticular structures that only make tip contact. Our results demonstrate the impressive performance and versatility of blepharicerid suction organs and highlight their potential as a study system to explore biological suction mechanisms.

Direct comparison of contralateral bias and face/scene selectivity in human occipitotemporal cortex

Human visual cortex is organised broadly according to two major principles: retinotopy (the spatial mapping of the retina in cortex) and category-selectivity (preferential responses to specific categories of stimuli). Historically, these principles were considered anatomically separate, with retinotopy restricted to the occipital cortex and category-selectivity emerging in the lateral-occipital and ventral-temporal cortex. However, recent studies show that category-selective regions exhibit systematic retinotopic biases, for example exhibiting stronger activation for stimuli presented in the contra- compared to the ipsilateral visual field. It is unclear, however, whether responses within category-selective regions are more strongly driven by retinotopic location or by category preference, and if there are systematic differences between category-selective regions in the relative strengths of these preferences. Here, we directly compare contralateral and category preferences by measuring fMRI responses to scene and face stimuli presented in the left or right visual field and computing two bias indices: a contralateral bias (response to the contralateral minus ipsilateral visual field) and a face/scene bias (preferred response to scenes compared to faces, or vice versa). We compare these biases within and between scene- and face-selective regions and across the lateral and ventral surfaces of the visual cortex more broadly. We find an interaction between surface and bias: lateral surface regions show a stronger contralateral than face/scene bias, whilst ventral surface regions show the opposite. These effects are robust across and within subjects, and appear to reflect large-scale, smoothly varying gradients. Together, these findings support distinct functional roles for the lateral and ventral visual cortex in terms of the relative importance of the spatial location of stimuli during visual information processing.

Uremic Stomatitis: A Case Report

Uremic stomatitis is a rarely reported oral mucosal disorder associated with renal disorder. It is mostly seen in cases of end stage renal disease or undiagnosed or untreated chronic renal failure. Its frequency has diminished due to the advent of renal dialysis. Clinically uremic stomatitis is characterised by the presence of painful plaques and crusts that are usually distributed on the buccal and labial mucosa, dorsal or ventral surface of the tongue, gingiva and the floor of the mouth. Ultimate treatment consists of improvement of blood urea concentration and underlying renal failure is supported by enhancement of oral hygiene with antiseptic mouthwashes and antimicrobial/ antifungal agents, if necessary. Here we report a case of a 50 year old Male patient who reported to the department with the complaint of inability to open mouth due to ulcers present intra-orally, who was a kidney patient undergoing dialysis, who was then treated with topical steroid and antifungal medications with follow up made once in a week.

Interclavicularis anticus digastricus muscle in a female body donor: a case report

Background and objectives Muscular variations of the ventral thoracic wall are generally common and of great clinical interest. Materials and methods An unusual muscular variation of the ventral thoracic wall was observed and dissected in a West-European female body donor. Results An interclavicularis anticus digastricus muscle was observed and studied. It originated from the manubrium sterni and inserted bilaterally to the clavicles. Both muscle bellies were interconnected by a tendon on the ventral surface of the manubrium sterni. The muscle was innervated by branches of the lateral pectoral nerve. Conclusions The interclavicularis anticus digastricus muscle is a muscular variation of the ventral thoracic wall of unknown prevalence. This variation might be of clinical interest in orthopaedics and thoracic surgery. It is also a vulnerable structure during infraclavicular insertion of a subclavian vein catheter or fractures of the clavicle.