The dental status of children with chronic renal failure

Resident: Hencler
Date: 01/15/2009

Article title: The dental status of children with chronic renal failure (CRF)

Author(s): Wolff, Stark, Sarnat, Binderman, Eisenstein, Drukker
Journal: The International Journal Of Pediatric Nephrology
Volume #6; Number 2; Page #127-132
Year: 1985

Major topic: Dental status and CRF

Type of Article: Clinical observation

Main Purpose:
Investigate the dental status of children with CRF to determine the prevalence and range of changes in dental structures and correlating these changes with metabolic disturbances, secondary to the uremic state, known to affect bone structure and development.

Overview of method of research:
Examined 30 children between 3-17 year old, 18 boys and 12 girls. Patients were divided into three groups according to their therapeutic regimens: (1) 15 on conservative therapy (2) 9 children on dialysis (3) 6 children who had undergone successful kidney transplantation. Eleven had primary dentition, 7 mixed, and 12 with permanent dentition. Hospital charts were reviewed for clinical and laboratory data. Every patient was evaluated for eruption age, enamel hypoplasia or hypocalcification, intrinsic staining, caries rate, gingival condition, and oral hygiene.

Findings:
• Dental Age and Eruption Age: Results demonstrate delay in both dental and eruption age for the 3 groups. Although some degree of retardation was found in both dental parameters, the delay in eruption was minimal, whereas retardation of dental age approached that in bone age.
• Enamel Defects: Location of the enamel defects clearly corresponded to the age at which renal function deteriorated and substantial biochemical disturbances occurred, namely, acidosis, hypocalcemia, hyperphosphatemia, and a rise in alkaline phosphate. There was a high incidence of enamel defects found in the CRF patients in this study.
• Intrinsic Discoloration: Found in the teeth of 9 patients. All cases of discoloration were found in parts of the teeth that developed postnatally. Discoloration was diffuse.
• Oral Hygiene and Gingival Condition: The patients in this study were compared to healthy patients with regards to OH and the gingiva. The authors found that both the OH and gingival indices were both higher for CRF patients in this study when compared to healthy patients.
• Caries: Measuring DMFT and comparing to healthy children, the results demonstrate a marked “protective” effect of CRF, especially in the younger age groups. The authors found a very low caries prevalence.
• Changes in the Jawbones: Absence of lamina dura (LD) was found in 6 and 3 showed loss of cortical borders of the mandibular canal (CBMC) and ground glass appearance of the bone structure. Radiographic changes were most frequent in the dialysis group.

Key points in the article discussion:
The 30 children with CRF clearly differed from a normal childhood population in all dental parameters examined. It appears that in CRF, development of the teeth is less sensitive to metabolic disturbances than that of bone. The degree of retardation was found to be a function of age at onset and duration of CRF and possibly also of steroid therapy in transplanted patients. The patients in this study had a very high incidence of enamel defects, in the form of hypoplasia and hypocalcification. Although the enamel defects have been attributed to hypocalcemia and Vit D deficiency, the authors were unable to relate them to any specific biochemical disturbance or therapeutic regimen. The increased incidence to staining with increasing severity of renal failure seems to be caused by pigments excreted by the kidneys. The poor condition of the gingiva in CRF patients appears to result from poor OH and high incidence of calculus. Poor OH reflects chronic ill health and tendency of parents to be more lax with these children. Reduced caries prevalence in uremic patients is surprising because to the poor OH and commonly recommended dietary regimens (low protein and high carb) for CRF patients. 4 explanations are as follows: (1) most of these patients suffer from anorexia and probably consume less food between meals reducing caries risk, (2) Recommended high fat diet reduce surface tension of the enamel that may lower plaque formation, (3) High salivary phosphate concentration found in uremia may facilitate remineralization of potential carious lesions, and (4) most importantly, the high salivary concentration of urea. Urea and it’s degradation products are both bacteriocidal and alkaline and is a highly effective agent for the prevention of caries. Radiographic changes of the jawbones are known to accompany other bone changes in CRF. Absence of the dental LD has been described in uremic patients. In dialysed patients, loss of LD was more common than loss of CBMC, whereas in transplanted patients the reverse was true because the LD is part of the liable alveolar bone whereas CBMC on the other hand belongs to the more stable basal bone. A ground glass appearance of jawbones is a finding of calcium metabolism disorders and hyperparathyroidism. The lower incidence of this finding in this study may reflect a shorter period of renal failure.

Summary of conclusions:
This study demonstrates that the metabolic defects associated with CRF do affect the development and structure of the teeth and alveolar bone. The nature and extent of these changes are a function of the age of onset of CRF and it’s duration. Despite low caries incidence, the finding of poor OH and resultant gingival changes suggests need for counseling and OHI. Antibiotic prophylaxis is very important when treating patients taking immunosuppressive treatment following kidney transplantation.

Assessment of article:
Good article, relevant to the pediatric dentist. Children with CRF will require special dental management including possible antibiotic prophylaxis and consults with PCP and nephrologists.