-
What did McKay do?
- observed "CO brown stain" (90% fluorosis)
- consulted GV Black
- 1916: Mottled enamel: developmental imperfection
- other reports seemed geograpically localized
- McKay suspected H20
- Oakley, Idaho - new pipeline coincided w/ fluorosis (1908), 1923 McKay suggest new H2O source 10 years later no more fluorosis (still didn't know it was Floride though)
-
What was the initial dilemna of mottled enamel?
Hypocalcified yet not susceptible to decay
-
What happened in Bauxite, Arizona?
- ALCOA, Bauxite kids w/ mottled enamel, 5 miles away normal
- ALCOA chemist-> HIGH FLORIDE CONTENT (seemed normal to McKay)
-
What did Dean do?
- recorded prevalence and severity of mottled enamel relative to [F] in H2O
- discovered dose-response relationship
- [F] up to 1ppm, mottling isn't a concern
-
What did they do in Grand Rapids, MI?
1945: adjust it's water supply [F]
-
What are some dental controversies?
- Fluoridated H2O
- Hg in amalgam
- Bis-Phenol A in sealants
- X-rays
-
What does scientific evidence say about Floridated water?
- safe & effective
- single most effective public health measure to prevent decay
- benefits everyone espicially w/o access
-
What is optimal Fluoride range?
- 0.7 ppm
- ok for environment and people
- mild to very mild fluorosis, cosmetic concern
- severe and moderate is rare (well water, outside US)
-
What is fluorosis prevalence in 6-49 yr olds?
- less than 1/4
- prevelence in younger is higher(multiple F sources) yet still mild/very mild
-
What are the issues with Fluoridated Water?
- Ethics, safety, efficacy
- compulsory mass meds
- potent poison
- brain damage/ reduced IQ
- inc fracture, bone CA
- thyroid activity
- topical not systemic
-
What is the pathogenesis of fluorosis?
- Normal pre-eruption enamel:
- 1. protein rich, 20% mineralized, seeded w HA crystals
- 2. matrix proteins break down->replaced by Ca & PO4
- 3. Matures slowly into highly (96%) mineralized tissue via crystalization (years)
- Excess Fluoride:
- 1. slows breakdown of matrix proteins or removal of proteins by by-products
- 2. Retards crystal growth
- 3. Hypomineralized enamel (normal ameloblasts & proteins)
- 4. NO HYPOPLASTIC CHANGES (pitting occurs post-eruption)
- Porosity in outer zones of enamel
-
How does hypomineralized enamel resist decay?
- Post-eruption maturation: enamel takes up additional Ca & PO4 fromsaliva
- Fluoroapatite is more resistant to dissolution than HA
-
Why is Fluorisis brown?
exogenous (foods/porous enamel stain prior to post-eruption maturation)
-
What is the difference between fluorosis and white spot caries lesions?
NOT limited to areas of plaque accumulation
-
What is the THylstrup Fejerskov (TF) index?
ID the spectrum of mildest(TF1) to most severe(TF9) fluorosis.
-
What are the CDC descriptors?
- Very mild & mild: scattered white flecks, occasional white spots, frosty edges, barely noticeable
- Moderate: large white spots
- Severe: roug, pitted(brown) spots
-
What are some treatments for Fluorosis?
- Enamel Microabrasion
- Remineralization (CPP-ACP)
-
What is the enamel Microabrasion process?
- Dr. Croll
- Abrasive paste: pumice & HCL
- controlled removal of outer enamel
- Products: Opalustre (Ultradent), Prema (Practicon)
- technique: patient eye protection, rubber dam, prophy cup (low RPM), 60 sec, rinse, assess contour, repeat
- Zacatecas Mx patient
- (brighter when dehydrated)
-
How does demineralization affect optical properties of enamel?
less transluscent & more reflective = white spot
-
What is MI paste?
- Amorphous Calcium Phospate stabilized by Casein Phosphopeptides (CPP-ACP)
- drives minerals deep into white spot to regain natural coloring/optical properties
- NON-invasive
- may be used with microabrasion
|
|