Review of the Class V amalgam - Dr. Mann

What are 2 non-invasive treatments of white spot lesions?

- ICON (infiltration of demineralized areas coupled with microabrasion) - MI paste (provides bioavailable Ca and PO4 to the white spot lesions to strengthen enamel) (have fluoridated and non-fluoridated options; but be careful if allergic to milk)

Where should class V retention grooves be placed?

- inciso-axial (occluso-axial) line angles - gingivo-axial line angles

What are two acceptable isolation techniques to provide better visibility and access?

- local anesthesia with 212 clamp and rubber dam isolation - local anesthesia with cotton roll and retraction cord (Most practical and often used method)

Which type of class V lesions would be restored with amalgam? (6)

- non-esthetic areas - patients with high caries rate (less expensive procedure) - access/visibility are limited - moisture control is difficult - deep subgingival areas - if the tooth is an abutment for an RPD

What are the steps for using a retraction cord?

- place cotton roles and dry area - cut retraction cord 1/4 inch longer than gingival margin (so you have something to grab to remove) - wet cord in dappen dish with hemodent - twist cord - 12L blunt instrument to pack cord (backward movement)

What are 3 major etiologies of the class V lesion?

- poor homecare and caries-inducing diet - gingival recession (exposed cementum/dentin increases opportunity for lesions) - medical conditions (such as sjogren's syndrome, medications, and head and neck radiation therapy)

Explain the 212 clamp placement technique

- use rubber dam forceps to expand clamp opening - position lingual jaw of clamp first - apical to height of contour - stretch facial rubber dam apical to lesion - position facial jaw of clamp .5-1 mm apical of lesion

The axial wall of a class V prep is approximately _____ mm depth at gingival and _______ mm depth at occlusal

.75; 1-1.25

When placing class V retention grooves, the depth of the grooves should be ____________________

0.25 mm (1/2 bur diameter of a quarter round bur -- slow speed! -- if there is limited access you can use a hand instrument to add retentive grooves)

Axial wall should be _______ beyond DEJ

0.2mm

When placing a class V amalgam you should maintain a minimal pulpal depth of _______ inside the DEJ or ___________ inside the CEJ

0.5 mm; 0.75 mm

If you see a class V outline form that approaches an existing class II alloy, what would be the best option? A. leave a thin section of tooth structure between the 2 restorations to separate them B. extend prep into existing class II

B

The axial wall of a class V prep is deeper at the ______________ surface A. gingival B. occlusal/incisal

B (due to contour of facial tooth surface)

The axial wall of a class V prep should be: A. straight B. convex C. concave

B (follow the natural outline shape of the tooth)

The axial wall of a class V prep should parallel ______________

DEJ and external tooth structure

Class _____ lesions are caused by the chronic presence of acidogenic plaque located in the non-self-cleansing area just below the height of contour of the tooth

V

True or false: class V retention grooves should bisect the line angle while marring the axial wall

false (shouldn't distort the axial wall)

Greater convexity is seen in the axial wall of a (larger/smaller) class V preparation

larger

Class V lesions tend to spread in a ________________ direction

mesial-distal (lateral)

An undercontoured class V amalgam restoration is a flattened facial surface often caused by _____________

overcarving

All mesial, distal, gingival, and incisal (occlusal) walls should be ____________ to the external tooth surface when prepping a class V amalgam restoration

perpendicular

What is the best method of isolation of the class V lesion?

rubber dam with appropriate clamp

True or false: braided or woven cord won't unravel during placement

true

True or false: the size of the class V restoration is determined primarily by size and location of caries

true

True or false: you should leave the retraction cord in place during tooth prep and insertion/carving

true

True or false: sometimes it is best to offer a full crown for teeth with extensive cervical decay

true (Dr. Mann especially does this on teeth #2 and #15 because it is hard to make sure you have removed all of the decay so problem will come back!)

True or false: incipient class V lesions without cavitation can be remineralized

true (minimally caveated surfaces can be smoothed with a sandpaper disc, polished, and treated with fluoride)

True or false: proper isolation of the class V lesion will enhance asepsis

true (will also prevent moisture contamination and facilitate access and visibility)

Overcontouring is typically caused by _______________ and results in a bulky restoration that cannot be cleansed well

undercarving

If you see significant blanching of tissue when placing a retraction cord what should you do?

use a cord with a smaller diameter

What would you do to remove deep caries on the axial wall of a class V lesion?

use a large round bur at slow speed (just as you would for pulpal floor of class I lesion)

Are retention grooves recommended for bonded alloys?

yes

One tip rubber dam isolation for a class V lesion would be to punch the hole for the affected tooth _______________ to normal arch alignment

1/4 inch facial (prevents bunching of rubber dam in cervical area)

____________ or _______________ is used for cord placement

12L plastic instrument; blunt bladed instrument

A rubber dam is used with the ______ clamp

212

How long should you wait to polish an amalgam restoration

24 hours

When using a rubber dam for a class V lesion you should isolate a minimum of _____ teeth

5

Amalgam restorations require ______ degree cavosurface margin

90 (this can be a disadvantage)

Which is strongest? A. amalgam B. composite C. glass ionomer

A

When preparing a class V amalgam preparation, what should be included in the prep?

all areas of decay and decalcification (white, chalky enamel)

What is the main difference between amalgam and composite class V preparations?

angulation of the enamel cavosurface margins (composite margins are beveled)

Place retraction cord in the sulcus (before/after) tooth preparation

before (cord will deflect gingiva and help with visibility)

What does the incipient class V lesion look like?

chalky white line just occlusal/incisal to the crest of the marginal gingiva

Class V preps should have a ____________ axial wall

curved

Local anesthesia (increases/decreases) salivary flow

decreases (this is beneficial for completing restorations)

Axial wall should be placed in sound (enamel/dentin)

dentin

All external walls of a class V amalgam restoration should (converge/diverge) facially

diverge (due to inclination of enamel rods)

Class V preps should have slightly (convergent/divergent) external walls

divergent

What should you remember about retraction cords and patients with heart conditions?

do not use the cord with epinephrine

Incipient class V lesions are usually on the (facial/lingual) surface of the tooth

facial

True or false: retentive grooves are not necessary for a class V amalgam restoration

false (recommended -- even for bonded alloys)