###### Abstract  
Chronic kidney disease (CKD) is an extremely widespread pathology characterized by numerous metabolic alterations, including impairments of calcium-phosphorus and of vitamin D metabolisms, which lead to a condition known as CKD-mineral and bone disorders (CKD-MBDs). In CKD children, this pathological condition induces anomalies in physiological growth processes, alterations in bone morphology, renal osteodystrophy and rickets. CKD-MBDs are not only associated with systemic complications but also show dental and maxillofacial manifestations in children. In fact, children affected by CKD-MBDs present defects in enamel development and dental anomalies when compared to healthy children. Therefore, the aims of this narrative review are to focus on the hard dental tissues and to investigate the possible correlation between the CKD-MBDs in children and the presence of developmental defects of enamel. In addition, the possible risk and protective factors of dental caries in CKD pediatric patients are analyzed. The review describes, with a multidisciplinary nephrological-dental approach, the pathogenic mechanisms that can cause anomalies in dental structure in CKD pediatric patients. chronic kidney disease; renal osteodystrophy; rickets; vitamin D deficiency; dental anomalies; maxillofacial manifestations; developmental defects of enamel; dental caries 2025151164  
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Introduction: Epidemiology of CKD in Pediatric Patients and Main Complications of CKD in Pediatric Patients  
Chronic kidney disease (CKD) is an extremely widespread pathology characterized by the progressive loss of renal function and is closely related to cardiovascular diseases, which represent its main cause of morbidity and mortality [1]. In particular, CKD is defined by \"Kidney Disease: Improving Global Outcomes\" (KDIGO) as an alteration of renal structure and/or function that persists for at least 3 months and which has implications for the individual's health [2]. The most recent epidemiological estimates suggest a global prevalence of 13.4% for CKD and it is estimated that this prevalence is destined to increase due to the growing spread of its risk factors, including arterial hypertension and diabetes mellitus and increasingly widespread unhealthy lifestyles [3]. CKD belongs to the non-communicable diseases and mainly affects the older population; in fact, CKD prevalence seems to increase proportionally together with advancing age [4], even though there are many children who are affected by this pathology. The data on CKD prevalence in children are insufficient. Its global prevalence ranges from 15 to 74.7 cases/million children [5]. In Europe, it has been estimated that its incidence in children is approximately 11-12 per million of the age-related population (pmarp) for stages 3-5, and approximately 8 pmarp for stages 4-5 [6]. The main causes of CKD in the pediatric population are congenital anomalies of the kidneys and the urinary tract. In fact, these represent up to 40-50% of all causes of CKD in children. These congenital anomalies provoke CKD, characterized by a slower progression to end-stage kidney disease (ESKD) and a higher risk of polyuria when compared to CKD in adults [5,7]. The second most common cause of CKD in children are hereditary nephropathies, which together with the congenital anomalies of the kidneys and of the urinary tract, represent 2/3 of all the CKD causes in children living in developed countries. On the other hand, the acquired causes are predominant in developing countries [6]. One of the main problems of CKD in children is that it may alter their physiological growth processes. In fact, children affected by CKD are often characterized by short stature due to substantial alterations in growth processes. The risk of growth retardation is greater the younger the child with CKD is. The causes that lead to the alteration of growth processes are various.