Type Clasp Indications Contraindications Advantages Disadvantages Akers' Clasp I. Tooth born partial denture

(removable bridge). II. On free-end extensions where undercut is so small that longer clasp arms will not be retentive.

I. Good support and bracing . II. Simple design . III. Dose not distort easily . IV. Easy to adjust . V. Contacts minimal area of the tooth . VI. Good esthetics.

May traumatize abutments when used incorrectly on free-end extension.

Ring Clasp Use on isolated lower molar with undercut located meso-lingually due to lingually tilted tooth.

It covers large area of the tooth making it unaesthetic, so it used only in posterior teeth.

Back Action Clasp (modification of ring clasp)

I. Premolar and canine abutments on free-end extension . II. On short teeth with small mesiofacial and distal undercut.

Not used on molars because of length of clasp arm.

I. Can use small undercut areas II. Length of clasp produces resiliency and "stress-breaking" effect on abutments for free-end extension partial denture.

I. Easily distorted because of length. II. Difficult to adjust. III. Large tooth area covered. IV. Design produces "food trap" between lingual arm and major connector.

Reverse Back Action Clasps (joining of a bar & back action clasps with all their disadvantages)

Premolar abutment with lingual inclination on free-end extension partial denture.

I. Maxillary partial denture for esthetic reasons. II. When there is a severe soft-tissue undercut inferior to marginal gingiva

Has "stress-breaking" action similar to "back action clasp".

I. Crosses soft tissue. II. Excessively long clasp, easily distorted, difficult to adjust. III. Poor esthetics. IV. Contacts large areas of tooth.

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Half & Half Clasp "Split Clasp"

I. Premolar and molar abutment for free-end extension P.D. and removable bridges . II. Isolated teeth.

I. Good support and bracing . II. Easy to adjust . III. Contacts minimal area of the tooth . IV. Good esthetics.

Food trap may be introduced between lingual arm and major connector if not constructed properly.

Type Clasp Indications Contraindications Advantages Disadvantages Reverse Action Clasp (Hairpin, C-Clasp, & Fishhook)

I. When a proximal undercut must be used to a posterior teeth and high tissue undercut prevents the use of a bar clasp. II. Distofacial undercut on canines and premolars when a sharp tissue undercut prevent use of bar-type clasp. III. Undercut near minor connector on molars.

On maxillary teeth where the metal is objectionable.

I. Undercut adjacent to edentulous area may be utilized without having minor connector cross soft tissue . II. Good bracing and support . III. May be used on free-end extension P.D. or removable bridges.

I. Poor esthetics . II. Large area of the tooth surface is covered . III. Possible food trap.

Embrasure Clasp (Butterfly Clasp or Double Akers' Clasp)

I. To utilize multiple abutments and distribute occlusal support and retention to several teeth . II. When insufficient undercuts are present on a single abutment . III. Specially used for the purpose of a bilateral bracing in a unilateral edentulous arch, to utilize a retentive undercut.

I. Not to be used where clasp would traumatize abutment teeth. II. Cannot be used where there is insufficient space for the minor connector to cross the occlusal surface.

I. Good support and bracing. II. Distributes support, bracing and retention to several teeth.

I. Minor connector usually too thin on occlusal surface resulting in excessive breakage. II. Retention may be excessive.

Multiple Clasps Two opposing circumferential clasps joined at the terminal end of the two reciprocal arms, used when multiple clasping is needed.

Mesiodistal Clasp On maxillary lateral incisors which are abutments for a removable bridge (tooth born partial denture) or tooth borne side of a unilateral free-end extension.

I. Good esthetic. II. Good support and bracing.

Tooth must be prepared by dentist so that proximal surfaces of the tooth are parallel or have slight convergence incisally.

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I. Small shallow undercut present in the cervical ⅓ of anterior teeth. II. Approaches the undercut is an inconspicuous (hidden) way; serve esthetically.

Type Clasp Indications Contraindications Advantages Disadvantages Round Wrought Wire Clasp

Canine & premolar abutments for free-end extension partial dentures.

Removable bridges. I. More flexible than cast arm. II. Easy to adjust. III. Good esthetics. IV. Minimal tooth surface contacted (line contact).

I. Easily distorted by careless handling by patient. II. Fabrication more time consuming.

Combination Clasp (Wrought wire retentive clasp arm + Cast reciprocal arm)

I. Flexibility II. Adjustability III. Esthetics

I. Fabrication . II. Distorted with careless handling.