FILLING OF CAVITIES

Classification by Black
Class I cavity preparations (pits and fissures) are one-surface preparations which involve the occlusal surfaces or the occlusal two-thirds of the facial or lingual surfaces of a posterior tooth or the lingual pits of maxillary anteriors.
Class II cavity preparations are those that involve the proximal surfaces of posterior teeth.
Class III cavity preparations are one-surface preparations that involve the proximal surfaces of anterior teeth.
Class IV cavity preparations are those that involve the proximal surfaces and the incisal angle of anterior teeth.
Class V cavity preparations are one-surface preparations that involve the gingival third of the labial, buccal, or lingual surfaces of any teeth.
Class VI cavity preparations are those that involve areas not normally affected by dental caries such as the incisal edges of anterior teeth and the cuspal tips of posterior teeth. This class is in addition to Dr. G. V. Black's original five classes.

First class preparation

Fifth class preparation

Preparation

Restoration
A dental restoration or dental filling is a dental restorative material is a dental restorative material used to restore the function, integrity and morphology is a dental restorative material used to restore the function, integrity and morphology of missing tooth structure. The structural loss typically results from caries is a dental restorative material used to restore the function, integrity and morphology of missing tooth structure. The structural loss typically results from caries or external trauma. It is also lost intentionally during tooth preparation is a dental restorative material used to restore the function, integrity and morphology of missing tooth structure. The structural loss typically results from caries or external trauma. It is also lost intentionally during tooth preparation to improve the aesthetics or the physical integrity of the intended restorative material. Dental restoration also refers to the replacement of missing tooth structure which is supported by dental implants.
Dental restorations can be divided into two broad types: direct restorations and indirect restorations. All dental restorations can be further classified by their location and size.

Dental restorative materials
AMALGAM
COMPOSITES Direct and Indirect
GLASS IONOMERS RESIN-
IONOMERS

FACTORS AMALGAM
General Description
A mixture of mercury and silver alloy powder that forms a hard solid metal filling. Self-hardening at mouth temperature.
Principal Uses
Dental fillings and heavily loaded back tooth restorations.
Leakage and Recurrent Decay
Leakage is moderate, but recurrent decay is no more prevalent than other materials.
Overall Durability
Good to excellent in large load-bearing restorations.
Cavity Preparation Considerations
Requires removal of tooth structure for adequate retention and thickness of the filling. Clinical Considerations
Tolerant to a wide range of clinical placement conditions, moderately tolerant to the presence of moisture during placement.
Resistance to Wear Highly resistant to wear.
Resistance to Fracture
Brittle, subject to chipping on filling edges, but good bulk strength in larger high- load restorations.

Metals and metallic alloys
Amalgam is widely used for direct fillings, and done in single appointment.

Dental composites
General Description
A mixture of submicron glass filler and acrylic that forms a solid tooth-colored restoration. Self- or light-hardening at mouth temperature.
Principal Uses
Esthetic dental fillings and veneers.
Leakage and Recurrent Decay
Leakage low when properly bonded to underlying tooth; recurrent decay depends on maintenance of the tooth-material bond
Overall Durability
Good in small-to-moderate size restorations.
Cavity Preparation Considerations
Adhesive bonding permits removing less tooth structure.
Clinical Considerations
Must be placed in a well-controlled field of operation; very little
tolerance to presence of moisture during placement.
Resistance to Wear
Moderately resistant, but less so than amalgam.
Resistance to Fracture
Moderate resistance to fracture in high-load restorations.
Post-Placement Sensitivity
Occurrence of sensitivity highly dependent on ability to adequately bond the restoration to the underlying tooth.
Esthetics
Mimics natural tooth color and translucency, but can be subject to staining and discoloration over time.

Composite restoration