**1. Introduction**

Ascorbic acid (vitamin C) plays the key role of a cofactor in several metabolic reactions involved in tissue growth, development and healing [1]. In fact, ascorbic acid enables collagen's hydroxylation [2]; then, it empowers the biosynthesis of carnitine and norepinephrine, and is also involved in the metabolism of tyrosine and the amidation of peptide hormones [3]. Vitamin C performs an important function in the immune system too: scorbutic individuals usually develop a higher incidence of infections, and vitamin C auxiliary therapy is actually considered for sepsis treatment support [4]. Generally, signs of ascorbic acid deficiency begin to show after about 30 to 90 days of insufficient vitamin C intake [5]; clinical findings are directly related to the various metabolic pathway which ascorbic acid is involved in [6]. Most of characteristic disorders of vitamin C deficiency can overlap with rheumatological, infectious or hematological diseases, showing a wide range of musculoskeletal and mucocutaneous manifestations, thus mimicking other pediatric conditions [7]. Scurvy is a well-known but uncommon disease, and nowadays is considered a rare condition in developed nations [8]. Despite its low frequency in the population, cases of scurvy still occur in people at risk, including elderly populations, patients affected by malabsorption syndromes and eating disorders, and, above all, pediatric

**Citation:** Gicchino, M.F.; Romano, A.; Cioffi, S.; Fiori, F.; Miraglia del Giudice, E.; Lucchese, A.; Olivieri, A.N.; Serpico, R. Oral Manifestations in Scurvy Pediatric Patients: A Systematic Review and a Case Report. *Appl. Sci.* **2021**, *11*, 8323. https:// doi.org/10.3390/app11188323

Academic Editor: Bruno Chrcanovic

Received: 26 July 2021 Accepted: 6 September 2021 Published: 8 September 2021

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patients with restricted or selective feeding [9]. These categories of people have chronically low levels of vitamin C, which cannot be intrinsically produced within the human body and therefore must be obtained via dietary intake [10]. The most common clinical features are hypertrophy, swelling and bleeding of the gums, follicular hyperkeratosis, lower limbs swelling and tenderness, poor wound healing [11,12]. Oral cavity signs represent peculiar characteristics in patients affected by scurvy; nevertheless, gingival overgrowth stands out as a typical manifestation of several diseases, resulting in differential diagnosis for idiopathic enlargement, drug-induced enlargement, enlargement associated with systemic diseases (such as Leukemia or Granulomatous diseases) and neoplastic enlargement (gingival tumors) [13,14]. Serological measurement of vitamin C is a readily available and widely used laboratory test; despite generally ascorbic acid serum levels accounts for the most recent food intake, they may be related to the level of reserves and predict the possibility of developing clinical signs [15]. Dietary restrictions and poor compliance with taking oral supplements appears to have brought scurvy back to the fore in the pediatric population, particularly in patients with neurodevelopmental disorders linked to highly selective diets [16]. Despite scurvy's return to clinical practice, the extreme heterogeneity of the clinical signs makes the identification of patients suffering from scurvy a very demanding challenge for the pediatric dentist [17]. The purpose of this study is to provide pediatric dentists with the means to identify clinical parameters and diagnostic tools useful for detecting patients suffering from scurvy. Here we present a case report of a patient with scurvy and a systematic review of the literature on scurvy in pediatric population.
