Lipid chemistry.pdf lipid for example shows how to make us

chemistry lipid Congenital and Developmental Anomalies of Permanent and Deciduous Posterior Teeth
Introduction
Congenital and developmental anomalies of teeth refer to variations in tooth number, size, form, and structure that occur during tooth development. These anomalies can affect both permanent and deciduous (primary) teeth. In this assignment, we will explore some common anomalies related to posterior teeth.

1. Congenital Anomalies of Teeth Number
Hypodontia
Hypodontia is characterized by the congenital absence of one or more permanent teeth.
It occurs when a permanent tooth fails to develop and emerge within the expected timeframe.
Patients with hypodontia may have missing incisors, premolars, or molars.
Early diagnosis and management are essential for proper treatment planning.
Hyperdontia
Hyperdontia refers to the presence of extra teeth beyond the normal dentition.
Supernumerary teeth can occur in various locations, including the posterior region.
These additional teeth may cause crowding, impaction, or other complications.
2. Congenital Anomalies of Teeth Size
Microdontia
Microdontia refers to abnormally small teeth.
It can affect single teeth or entire dentitions.
Microdontia may lead to functional and aesthetic challenges.
Macrodontia
Macrodontia involves abnormally large teeth.
It can result from genetic factors or localized disturbances during tooth development.
Macrodontia may cause occlusal problems and esthetic concerns.
3. Congenital Anomalies of Teeth Form and Structure
Localized Processes
Gemination
Gemination occurs when a single tooth bud partially splits into two teeth.
The fused tooth appears larger than normal and has a unique shape.
Commonly affects incisors and canines.
Fusion
Fusion results from the union of two adjacent tooth buds.
The fused teeth share a common pulp chamber and root canal.
May lead to altered occlusion and hygiene challenges.
Taurodontism
Taurodontism involves an enlarged pulp chamber and elongated roots.
The pulpal floor is displaced apically.
Seen in molars, especially in patients with certain genetic conditions.
Dens Invaginatus
Dens invaginatus (also called “dens in dente”) is a malformation where enamel invaginates into the pulp chamber.
Predisposes the tooth to caries and pulpal infections.
Dens Evaginatus
Dens evaginatus is an accessory cusp on the occlusal surface.
More common in premolars.
Requires careful restoration to prevent fracture.
Dilaceration
Dilaceration refers to a sharp bend or curve in the root of a tooth.
May result from trauma during tooth development.
Can complicate extraction or orthodontic treatment.
Enamel Pearl
Enamel pearls are small, spherical enamel projections on the root surface.
Often found near furcation areas.
May contribute to periodontal problems.
Turner’s Hypoplasia
Localized enamel hypoplasia due to trauma or infection during tooth development.
Results in pits or grooves on the enamel surface.
4. Radiographic Examinations
Radiographs (such as cone-beam compu

1. FieldofMedicine
MedicineAndSurgery Program
Lecture:Lipidchemistry
Date:19/3/2024Dr:MoatazMaherand Abeer Eid

2. LipidChemistry

3. Objectives:
Bytheendofthislecture,thestudentwillbeable to:
1.DefineLipidsandenumeratetheirfunctions.
2.Recognizethegeneralclassificationoflipids
3.Describethegeneralstructureandcharactersoffattyacids.
4.Recognizeimportantformsof lipids&theirroleinthehumanbody

4. 1a.NatureofLipids
Lipidsarea collectionof organicmolecules,having the following properties:
Theyarehydrophobicduetothepresenceofapolyhydrocarbon chain
(—CH
2)
nintheirstructure.
Theyareinsolubleor poorlysolubleinwater,butreadilysolublein
nonpolarsolventssuchasetherandbenzene.

5. 1b.BiologicalFunctionofLipids
1.Importantdietaryconstituent:
-They are used as a source and storage form of energy ( in adipose
tissue).1g offatprovides9kcal.
-Lipid-solublevitamins(A,D,E, andK) aresuppliedbydiet
-It’stheonly sourceofessentialfattyacids neededbythehumanbody.
2.Theyserveascellularconstituentsinthecellmembrane&
mitochondria
3.Protectionand supportof the internal organs as fat acts as shock
absorber
4.Source of hormones(e.g., Steroidhormones).
5.Thermalinsulators.

6. 2.LipidClassification
1.Simple
-Estersoffattyacids(FA)with
variousalcohols
1.Fats–estersofFAwith
glycerol(liquid stateis-OIL)
2.Waxes –esters of fatty acids
withhighermolecularweight
alcohol
2.Compound (Conjugated)
-EstersofFAscontainingothergroups
inadditiontoanalcoholandaFA
1.Phospholipids
2.Glycolipids
3.Lipoproteins are complexes of
proteins and lipids e.gVLDL, LDL and
HDL
3.DerivedLipids
Theyaresubstancederivedfromhydrolysis oftheprevious2 groups(simple and
complex) or produced from a lipid compound. They include fatty acids, glycerol,
cholesterol,andhormones (Steroidhormones)

7. 3.GeneralFeaturesof Fatty acids
I.Theyarelong-chainmonocarboxylicacids
II.Theyusuallycontainanevennumberofcarbonatomsand fatty acid has
amphipathic nature (i.e. having both a hydrophilic and a hydrophobic region).
O
RCOH
Non-polarEnd-HydrophobicEnd
(Fat-solubletail)
PolarEnd-HydrophilicEnd

8. 3.GeneralFeaturesof Fatty acids
III.Fattyacidsnumbering:
-Carbon atoms are numbered
from the carboxyl carbon
(C1).
-Carbon atom adjacent to C1
(C2)isα-carbon.
-C3andC4are theβ-andγ
carbons.
-Terminalcarbonis
ω-carbonorn-carbon.

9. 3.GeneralFeaturesofFatty acids
IV.Classificationof Fattyacids
1.According tothelengthoftheCarbonChain
-Short-chain(Lessthan8carbons)
-Medium-chain(8-10carbons)
-Long-chain(Morethan10 carbons)
2.Accordingtothe degree ofsaturation
-Saturated=containsno doublebonds
Palmiticacid(16:0)
-Unsaturated=Containsoneormoredoublebond(s)(MonoorPolyunsaturated)
Palmitoleicacid(16:1;9)

10. 3.GeneralFeaturesofFatty acids
V.Somefattyacids(FA)shouldbesuppliedindiet.Thesefattyacids
arecalled“essentialFA”.
1.Nonessentialfattyacidscanbesynthesizedfromproductsofglucose
and,therefore,do nothavetobe includedinthediet.
2.Essentialfattyacidsmustbeobtainedfromthediet[ω-3FA:Linolenic
acid(18:3);ω-6FA:Linoleicacid(18:2)].

11. 4.LipidsOfPhysiological Importance
4a.Triacylglycerols
They are the most important and main storage form of lipids in
man(adipocytes).
Triacylglycerol=
Glycerol+3fattyacids
(R
1,R
2,R
3)
TAG is producedbytheesterificationof
glycerolwiththreefattyacids
CH2-COO-R1
|
R2-COO-CH
|
CH2-COO-R3

12. 4.LipidsOfPhysiological Importance
4a.Triacylglycerols
Fat
Triglyceridescontaininghigh
proportionoflong-chain, saturated
fattyacids
Oil
Itisliquid fat
Containsbothunsaturated fattyacids
and saturatedfatty acids.
Hardening:
Itisthehydrogenationofoilstoform
solidfats(margarine).Thisprocess
involvesconversionofUSFAtoSFA.

13. 4.LipidsOfPhysiological Importance
•Theyaremainlipidconstituentsof membranes.
•They arederivedfromglycerol-3-phosphate
•They contain 2 long chain fatty acids at C-1 and C-2 of glycerol-
3-phosphate
•At C-3, the glycerol is esterified to
phosphategroupand
anOHcontaining
compound[X].
4b.Phospholipids
Glycerophospholipids Sphingophospholipids

14. 4.LipidsOfPhysiologicalImportance
4b.Phospholipids
Inthemembrane,thepresenceofthephosphategroupinglycerophospholipidsmakespartofitpolar
[head]whilethefattyacidisnonpolar[tail].
Examplesofglycerophospholipids
Phosphatidylcholine(lecithin):Mostabundantphospholipidsofcellmembrane
DipalmitoylLecithin: A major constituent of lung Surfactant.
•lung surfactant prevents adhesion of inner surfaces of the lungs.
Cardiolipinwhichis themajorlipid oftheinner mitochondrialmembrane.

15. 4.LipidsOfPhysiological Importance
4b.Phospholipids
Glycerophospholipids Sphingophospholipids
Sphingolipidsarecomponentsofmembranesandarepresentin
nearlyallhumantissues.
Theirstructureincludessphingosine(NOTGlycerol),an18Calcohol,
+fattyacid+phosphate+others.
Thegreatestconcentrationofsphingolipidsisfoundinthecentral
nervoussystem(CNS)andisknownasSphingomyelins.Theyactas
insulatorsof thenervefibers.

16. 4.LipidsOfPhysiological Importance
•Theyarewidelydistributedinourbodyparticularlyinthenervoustissues
•Majorglycolipidsinthebodyareglycosphingolipids=they
aresphingolipidsthatcontaincarbohydratemoieties.
Importance of Glycolipids:
1. Glycolipids are found in cell membranes, especially in myelin sheath.
2. Cell membrane receptorsare glycolipids in nature.
3. Glycolipids are important constituents of nervous tissue.

17. 4.LipidsOfPhysiological Importance
Steroidsarelipidsthatcontainfourfused carbonringsthatform aringknown asthe
“steroidnucleus”.
Examples:
-Cholesterol
-Steroid hormones
-Bileacids
-VitaminD.

18. 4.LipidsOfPhysiological Importance
Cholesterol(27C)isthemajorsteroidinthehumanbody.Itistheparent
moleculefromwhichmostofderivedlipidsaresynthesized.
Normallevel120to200mg/dL.
Importance:
-Steroid hormones
-Bileacids and bile salts.
-VitaminD.
-Present in cell membrane

19. 4.LipidsOfPhysiological Importance
Importanceofbileacidsandbilesalts:Afteringestionofafattymeal,the
presenceofbilesaltsintheintestineisimportantforthedigestionand
absorptionoffatsaswellasfat-solublevitamins.Asbilesaltshelpto
emulsifyfatsintheintestine(emulsification).

20. SUMMARY
•Lipidsarepolyhydrocarbonsthatareinsolubleinwater.
•Theyareclassifiedintosimple,complexandderivedlipids.
•Fattyacidscanbeevenor odd,saturatedor unsaturated,essential
andnon-essential.Theyhavedifferentmeltingpointsthatdependon
thenumberof carbonsandunsaturatedbonds.
•Importantlipidsinhumanincludetriacylglycerols,phospholipids,
glycolipidsandcholesterol.

21. Reference:
–Lippincott'sIllustratedReviews:Biochemistry,7thEdition.Chapter16 &17.

22. Bestwishes