INBDE Operative Exam 2025
Questions and Answers
what are enamel and dentin mainly composed of? - ANSWER✔✔-carbonate substituted
hydroxyapatite
teeth are made of CHA ___% by volume and ____% by weight - ANSWER✔✔-85
95
what three minerals make up enamel - ANSWER✔✔-hydroxyapatite
fluorapatite
chlorapatite
· Bacteria secretes _________ and that's what causes decay or demineralization. It pulls
phosphate and calcium out of the tooth. - ANSWER✔✔-lactic acid
what is the critical pH for teeth - ANSWER✔✔-5.5
enamel and dentin begin to demineralize ____ mins after exposure - ANSWER✔✔-10
, - ANSWER✔✔-Saliva HCO3- grabs the H of sugars and acids and protects our teeth by
neutralizing the pH (buffer)
how long does it take saliva to differ the pH back to normal - ANSWER✔✔-30 min
fluoride lowers the critical pH to what? - ANSWER✔✔-4.5
what sugar most commonly causes caries - ANSWER✔✔-sucrose
how does fluoride work? - ANSWER✔✔-o Decreases enamel solubility (lowers critical
pH)
o Interferes with metabolic activity of cariogenic bacteria
what is the critical pH of dentin and cementum - ANSWER✔✔-6.2-6.7
what four things are needed for caries to form - ANSWER✔✔-o Host
o Time
o Biofilm
o Carbohydrates
what does the lesion look like in pits and fissures - ANSWER✔✔-starts small and gets
big
what do smooth surface lesions look like - ANSWER✔✔-starts big and gets small
what do root surface lesions look like - ANSWER✔✔-
Questions and Answers
what are enamel and dentin mainly composed of? - ANSWER✔✔-carbonate substituted
hydroxyapatite
teeth are made of CHA ___% by volume and ____% by weight - ANSWER✔✔-85
95
what three minerals make up enamel - ANSWER✔✔-hydroxyapatite
fluorapatite
chlorapatite
· Bacteria secretes _________ and that's what causes decay or demineralization. It pulls
phosphate and calcium out of the tooth. - ANSWER✔✔-lactic acid
what is the critical pH for teeth - ANSWER✔✔-5.5
enamel and dentin begin to demineralize ____ mins after exposure - ANSWER✔✔-10
, - ANSWER✔✔-Saliva HCO3- grabs the H of sugars and acids and protects our teeth by
neutralizing the pH (buffer)
how long does it take saliva to differ the pH back to normal - ANSWER✔✔-30 min
fluoride lowers the critical pH to what? - ANSWER✔✔-4.5
what sugar most commonly causes caries - ANSWER✔✔-sucrose
how does fluoride work? - ANSWER✔✔-o Decreases enamel solubility (lowers critical
pH)
o Interferes with metabolic activity of cariogenic bacteria
what is the critical pH of dentin and cementum - ANSWER✔✔-6.2-6.7
what four things are needed for caries to form - ANSWER✔✔-o Host
o Time
o Biofilm
o Carbohydrates
what does the lesion look like in pits and fissures - ANSWER✔✔-starts small and gets
big
what do smooth surface lesions look like - ANSWER✔✔-starts big and gets small
what do root surface lesions look like - ANSWER✔✔-
