Which factor contributes to the development of bone diseases in patients with Chronic Kidney Disease (CKD) due to retention?

Correct Answer: D

Rationale: The correct answer is phosphorus. Retention of phosphorus in patients with Chronic Kidney Disease (CKD) contributes to the development of bone disorders, including osteodystrophy, because it disrupts the balance of calcium and phosphorus in the body. This imbalance leads to a variety of bone diseases. The other options - iron, sodium, and potassium - while important in the overall metabolic function, are not directly linked to the development of bone diseases in CKD patients due to retention.

Correct Answer: D

Rationale: The first statement is incorrect because dental caries are not solely caused by sucrose. They are the result of a complex interaction of multiple factors, including the type of bacteria in the mouth, the host's diet, oral hygiene, and salivary flow. The second statement is correct as consuming sugar in moderation and limiting the frequency of sugar exposure are indeed effective strategies to prevent dental caries. Therefore, the answer is option D: The first statement is false; the second is true.

Correct Answer: B

Rationale: All the statements above are accurate about oral exposure to fermentable carbohydrates, except for option B. In fact, longer exposure to these carbohydrates decreases the opportunity for remineralization. This is because the process of demineralization, in which minerals are lost from the tooth enamel, is sped up by the presence of fermentable carbohydrates. The Stephan curve (option C) is a graph that demonstrates how the pH of dental plaque changes after a sugar rinse, usually dropping (becoming more acidic), which can lead to enamel decalcification. Option D is also accurate, as a pH of 5.5 or lower is the critical point at which enamel starts to decalcify.

Correct Answer: D

Rationale: MI Paste is contraindicated in children under six and in individuals with a milk casein allergy. The reason is that MI Paste contains casein phosphopeptide, which is derived from milk. Therefore, it may cause allergic reactions in those who are sensitive to milk proteins. Pregnant women (Choice C) are not contraindicated for using MI Paste unless they have a known allergy to milk casein. Hence, the correct answer is 'D: Both A and B'.

Correct Answer: C

Rationale: Adolescence is the most critical stage for building bone mass, which plays a significant role in preventing osteoporosis in later life. During adolescence, approximately 45% of adult bone mass is formed. Although bone mass can be built during infancy, early childhood, and young adulthood, it is not as significant as during adolescence, making choices A, B, and D incorrect. Therefore, focusing on adequate nutrition and physical activity during adolescence is vital for long-term bone health.