Presentation on theme: "General Dentistry/ Matrix Systems"— Presentation transcript:
1 General Dentistry/ Matrix Systems Chapters48 & 49
2 Restorative Dentistry Indicated when teeth must be restored to their original structure by the use of direct or indirect restorative materials.Conditions that determine the need for restorative dentistry:Initial or recurring decayReplacement of failed restorationsAbrasion or wearing away of tooth structuresErosion of tooth structure
3 Esthetic DentistryPrimarily devoted to improving the appearance of teeth by either restoring imperfections with direct or indirect restorative materialsSpecific conditions that initiate a need for esthetic treatment include the followingDiscoloration due to extrinsic or intrinsic stainingAnomalies caused by developmental distrubancesAbnormal spacing between teethtrauma
4 Cavity PreparationProcess of removing unhealthy tooth structure while leaving a limited amount of healthy tooth structure for the tooth to maintain a restorationTwo stages:Initial preparationAccess to decayOutline formPrimary resistance form
5 Final preparation Remove any remaining enamel in the prep Additional resistance and retentionPlace protective materials
6 Terminology Cavity Wall: Internal wall: External wall: Internal surface of tooth prepared for the restorationInternal wall:Cavity wall/surface that does not extend to the external tooth surfaceExternal wall:Surface of the tooth preparation that extends to the external tooth surface, named according to the tooth surface involved; distal, mesial, facial, lingual, gingival
7 Axial wall: Pulpal wall: Internal wall/surface of the prepared tooth that runs parallel to the long axis of the toothPulpal wall:Internal wall/surface of a prepared tooth that is perpendicular to the long axis of the tooth; also known as the pulpal floor
8 Line angle:Angle formed by the junction of two walls/surface in a cavity preparation (such as a corner)The names of the two walls are combined and form a new angle. Such as mesial and lingual, and becomes mesiolingual angle.
9 Classifications Class I Class II Class III Small and involves the pits and fissures of teethClass IIExtension of Class I, into the proximal surface(s) of premolars and molarsClass IIIAffects the interproximal surface (mesial or distal) of incisors and canines
10 Class IVInvolves larger surface area, that includes the incisal edge and the interproximal surface of incisors and caninesClass VSmooth surface restorationsGingival third of the facial or lingual surfaces of any tooth
11 Complex RestorationsWhen the loss of the tooth structure becomes greater than the remaining natural tooth that is left.Decision has to be made whether to restore with a crown or direct restoration (such as amalgam or composite)If a direct restoration is decided upon, Retention Pins may be needed. Pins provide stronger system for retaining and supporting the restoration other than retentive grooves or bonding materials
12 Retention PinsMay be required when tooth decay has extended into the distolingual cusp, undermining the enamel and dentin.One pin would be placed for each missing cusp
13 VeneersA thin layer of tooth colored material that is applied to the facial surface of a prepared tooth.Can be used for more than one toothImproves appearance, (such as)Slightly abradedErodedDicolored (intrinsic stains or after endo treatment)Alignment (diastema)
14 Tooth Whitening Also known as Vital bleaching Noninvasive method of lightening of teethIn office and at-home methodsThree primary indications for useExtrinsic stains from foods, smoking, coffee or teaAged teethIntrinsic stains (tetracycline stains and mild fluorosis
17 Matrix SystemsCreates a temporary wall for amalgam, composite resin or IRM materialPosterior Matrix systemsTofflemire retainerKnow the parts of the retainer and their functionBandMade of thin flexible stainless steelCenter of the band must be contoured(shaped) in the proximal surfaces for contact
18 Matrix Cont. Wedges Class II restoration require wedges Placed on lingual embrasureVarious sizes and forms, wood or plastic
19 Anterior Matrix Clear plastic Used with composite resin or glass ionomerStainless steel matrix can scratch or mark the composite resin materialAlso referred to as celluloid strip or Mylar strip.
20 Automatrix System Alternative to the use of Tofflemire system Does not use retainer to hold in placeBands are already formed
21 Matrix Systems for Primary Teeth T-bandsCopper band in shape of a TWhen formed the top of the band allows the straight portion to adjust and fit the circumference of the primary molar.