General Dentistry and Matrix Systems Flashcards
Restorative Vs Esthetic Dentistry
The general dentistry consists of restorative and esthetic dentistry.
What are the conditions for restorative and esthetic work?
- conditions for restorative:
- Initial or recurring decay
*Replacement of failed restorations. - abrasion or the wearing away of tooth structures
- Erosion of the teeth structure.
- conditions for esthetic:
- Discoloration due to extrinsic or intrinsic staining
*Anomalies due to development disturbances
*Abnormal spacing between teeth - Trauma
Cavity preparation
two steps for Cavity preparation:
- Initial cavity preparation: first of two stages of cavity preparation. It has a set of number of steps that the dentist follow in an exact order. The process is performed to gain access to the decay or defect:
- outline form: design and initial depth of sound tooth structure
*Resistance form: shape and placement of cavity wall
* Retention form: to resist displacement or removal
*Convenience form: provides accessibility in preparing and restoring the teeth.
- Final cavity preparation: Is the second stage of cavity preparation . It consists of the steps:
- removal of decayed dentin or old restorative material
- insertion of resistance and retention with use of hand cutting instruments and burs.
*placement of protective materials.
Restorative procedures
dental assistants have responsibilities during restorative procedure.
- Preparing the setup for procedures
- knowing and anticipation the dentist’s needs.
- providing moisture control
- transferring dental instruments and accessories
- mixing and transferring dental materials.
6.maintaining patient comfort
Preparing the patient for the restorative procedure:
1. Inform the patient what to expect throughout the procedure.
- position the patient correctly for the dentist and type of procedure.
- Explain each steps to the patient as the procedure progresses
Restorative procedures steps
After the patient is prepared, the restorative procedure proceeds steps by steps:
step 1: dentist evaluates the tooth to be restored
step 2. Dentist administers local anesthesia
step 3. Assistant readies the chosen means of moisture control.
step 4.Dentist prepares the tooth
step 5. Dentist determines the type of dental materials
step 6: assistant mixes and transfers the dental materials.
step7: dentist burnishes, carves, or finishes the dental materials.
step 8: dentist checks the occlusion of the restoration:
step 9: dentist finishes and polishes the restoration.
classification of lesions
cavities also are referred to as lesions. Lesions are identified as being in one of six classes. It is important to recognize the class of lesions because the preparation of the affected tooth depend in what class of lesion is involved.
Class I: includes caries that affect the pit and fissures of the teeth.
The location of class I caries and restoration include:
A- Occlusal pit and fissures of posterior teeth
B- Buccal pits and fissures of posterior teeth
C- lingual pits and fissures of maxillary molars
D- lingual pits of the maxillary incisors.
Class II: included caries that are an extension of a class I lesion into proximal surfaces of the posterior teeth. Class II lesions affect two or three surface restorations of posterior teeth.
Class III: refers to a carious lesion that involves the inter-proximal surface of incisors and canines.
class IV: refers to carious lesion that involves a larger surface area, including the incisors edges and inter-proximal surface of the incisors and canines.
Class V: refers to carious lesion involving the ginival third of. the facial or lingual surface of any tooth, or the toot of tooth near the cementoenamel junction.
Class VI: refers to carious lesion found along the incisal adage of the anterior teeth or on the occlusal cusps on a posterior tooth.
complex restorations: are required when decay has extended beyond the normal size or shape.
Retention pins: are used when decay has extended into the cusp of tooth and undermined the enamel and dentin. Commonly are used in tooth or retaining and supporting a restoration.
A drill is used to place the pin a prepared tooth. No cementation of the pin is required. The extended portion of the retention pin is open to adhere to restorative materials that will be placed.
Intermediate restorations
some restoration are intended to be placed for just a short time. Intermediate restorations are temporary and are not to serve as permanent solutions.
Principal reasons for placement f an Intermediate restorations:
1. The health of tooth need be determined
2. there is a wait for a permanent restoration
3. patient’s financial situation required the use of an intermediate restoration.
Direct Bonded veneers
The veneer is a thin layer of tooth colored materials applied to facial surface of the prepared tooth.
Direct veneers are made of resin composite material. Direct veneers are not fabricated by dental laboratory technician
Veneers are commonly used for teeth that have been
-Abraded
-Eroded
-Discolored with intrinsic stains
- darkened after endodontic treatment.
Tooth whitening
Tooth whitening is a noninvasive method of lightening dark or discolored teeth. Tooth whitening is performed on teeth that are “vital” or have live nerves is referred to as vital beaching.
vital beaching.: tooth whitening that is performed on teeth that are vital are vital or have live nerves.
Indication for tooth whiting include:
- Aged or discolored teeth
- Extrinsic stains: stains on the surface of tooth caused by food, coffee or tea
- Intrinsic stains such as mlid tetracycline stains and mild fluorosis.
Tooth whiteners have the chemical makeup described there
- Active ingredient: carbamide peroxide or hydrogen peroxide.
- Gel base: one or a mixture of following items:
- propylene glycol
- glycerin
- water
-Thickener: carbopol
Tooth whitening methods and potential issues
several tooth whitening are available that patients can use at home.
Tooth whiting strips also are available. These are thin flexible strips coated with an adhesive hydrogen peroxide whitening gel.
The patient peels off the paper backing and presses the strips of the facial anterior teeth. The remaining portion of the strip is folded onto the lingual surface.
Complication from tooth whitening:
- Thermal hypersensitivity: patient might experience sensitivity to heat and cold after remove of the tray and material. The use of tooth of toothpaste for sensitive teeth is recommend.
- Tissue irritation: gingival tissue exposed to excess gel as a result of improper tray fit might become irritated. The patient should be instructed to not overfill the tray with material and to remove any excess after excess the tray.
Tooth whitening and dental assistant
-Aids in recording the medical and dental history
- assists in making shade selection
- Takes intraoral photographs before and after whitening
-Takes and pours up preliminary impressions for tray.
- Fabricates and trims the tray
- provides postoperative instruction
- assists in weekly or biweekly clinical visits.
Instructions for tooth whiting procedure
- Brush and floss before tray placement
- place equal amount of gel in tray
- seat the tray
- do not eat or drink while wearing the tray
- wear the tray for the recommended time
posterior matrix system
Class II, III, IV restorations require the use of matrix system in order to restore the proper form, contour and contact to the tooth surface.
matrix system: provides a temporary wall for the restoration process in class I,III< IV preparations.
-Universal retainer: holds the matrix band in position. It also referred to as Tofflemire retainer. The Universal retainer is most commonly positioned from the buccal surface of the tooth being restored.
Matrix bands are used to prevent restorative materil from bonding to other teeth. matrix bands are made of thin, flexible stainless steel. They comes in two common design: Universal retainer. Larger circumference matrix ands are placed on occlusal edge of tooth. Smaller circumference bands are placed on gingival edge.
Cavity preparation
wedges are positioned into lingual embrasure of a class II preparation after band placement to slightly pry apart teeth if the caries is between two teeth.
Wedges are available in various:
- Size
- shapes (triangular or round)
-materials (wood or plastic)
During transfer ask the dentist what size wedge is appropriate
Anterior metric systems
Anterior metric systems is plastic matrix that does not use retainers. Metal bands are not used because the resin/composite material can be scraped or marked by the stainless steel. An anterior matrix also is referred to as a celluloid matrix or a mylar strip. they are used in class III and IV restorations.
AN anterior matrix is placed inter proximally before the etching and bonding of tooth. After the placement of composite material, a matrix is pulled tightly around the tooth to help reconstruct its natural contour. The clear plastic matrix allows curing light to penetrate the material and complete the curing process.
