Pinledge Preparations

A pinledge (Fig. 10-34) is occasionally used as a single restoration, generally to reestablish anterior guidance, in which case only the lingual surface is prepared. More commonly, however, it is used as a retainer for a fixed partial denture (Fig. 10-35) or to splint periodontally compromised teeth (Fig. 10-36). In these cases, one or more of the proximal surfaces are included in the preparation design to accommodate the required connector(s). Retention and resistance are provided primarily by pins that extend to a depth of 2 mm into dentin. Compared to other retainers, the pinledge preparation is very conservative of tooth structure.

The preparation steps themselves are not difficult, but advance planning and a thorough understanding of the various steps are prerequisites to success. Diagnostic preparation on an accurate cast is particularly useful during the planning phase. Preparation of a number of parallel pinholes with a common path of withdrawal can be intimidating. With some practice, however, this can be accomplished freehand by most operators, especially when a tapered bur is used. Paralleling devices are available for practitioners who do not feel comfortable preparing multiple pinholes. Generally, pinledges are highly esthetic restorations. Plaque control after treatment is easier because of short margin length and largely supragingival margin location.

Indications. The pinledge is indicated for undamaged anterior teeth in dentitions with a low caries experience. The presence of a small proximal carious lesion, however, does not preclude its use. If a high esthetic requirement exists, the advantage of this restoration is that the labial tooth surface

*The twist drills supplied with threaded pin kits for amalgam retention are suitable.

Pinledge Retainer

Fig. 10-33. A, Completed three-quarter crown preparation on a maxillary canine. B, The contralateral canine. C, A three-quarter crown serves as the anterior retainer for a three-unit FPD; its female intracoro-nal RPD rest is incorporated in the mesial box. D, Note the connector and the open embrasures on the contralateral side. E to G, Labial views of the cemented FPDs. H, The definitive RPD.

Fig. 10-33. A, Completed three-quarter crown preparation on a maxillary canine. B, The contralateral canine. C, A three-quarter crown serves as the anterior retainer for a three-unit FPD; its female intracoro-nal RPD rest is incorporated in the mesial box. D, Note the connector and the open embrasures on the contralateral side. E to G, Labial views of the cemented FPDs. H, The definitive RPD.

Pinledge Crown

Fig. 10-34. The pinledge preparation on a maxillary central incisor. A, Guiding grooves placed for lingual reduction. B, The lingual reduction completed and an incisal bevel placed. C, Incisal and cervical ledges prepared. D, Indentations have been made. Note the spacing of the ledges relative to each other and to the pulp. All pinholes will be in sound dentin. E, Pinholes prepared to a depth of 2 mm. The junction between the ledge and the pinholes has been countersunk.

Fig. 10-34. The pinledge preparation on a maxillary central incisor. A, Guiding grooves placed for lingual reduction. B, The lingual reduction completed and an incisal bevel placed. C, Incisal and cervical ledges prepared. D, Indentations have been made. Note the spacing of the ledges relative to each other and to the pulp. All pinholes will be in sound dentin. E, Pinholes prepared to a depth of 2 mm. The junction between the ledge and the pinholes has been countersunk.

Pinledge Retainer

Fig. 10-35. A, Modified pinledge serving as a retainer for a four-unit FPD. An additional pinhole was placed in the cingulum and in the cervical aspect of the proximal groove; in the latter instance, this was done because insufficient tooth structure remained to provide resistance against lingual displacement. B, The FPD on the master cast. C, A four-unit FPD consisting of a modified pinledge, two metal-ceramic pontics, and a metal-ceramic crown.

Fig. 10-35. A, Modified pinledge serving as a retainer for a four-unit FPD. An additional pinhole was placed in the cingulum and in the cervical aspect of the proximal groove; in the latter instance, this was done because insufficient tooth structure remained to provide resistance against lingual displacement. B, The FPD on the master cast. C, A four-unit FPD consisting of a modified pinledge, two metal-ceramic pontics, and a metal-ceramic crown.

Pinledge Retainer

Fig. 10-36. A, Periodontally compromised but caries-free teeth of adequate buccolingual width are excellent candidates for a pinledge retained fixed splint. B, The master cast. C, Pinledge splint consisting of six separate castings that were soldered together and seated. D, A minimum display of metal results. The pinledge preparations permit retention of the intact labial enamel of all six anterior teeth.

Fig. 10-36. A, Periodontally compromised but caries-free teeth of adequate buccolingual width are excellent candidates for a pinledge retained fixed splint. B, The master cast. C, Pinledge splint consisting of six separate castings that were soldered together and seated. D, A minimum display of metal results. The pinledge preparations permit retention of the intact labial enamel of all six anterior teeth.

remains intact, although this is sometimes offset by the display of a slight amount of metal along the incisal edge. Pinledges can be prepared on bulbous teeth that are unsuitable for three-quarter crowns, which would result in a significant amount of unsupported enamel interproximally. The lingual concavity of a maxillary anterior tooth can be modified successfully with a pinledge restoration (see Fig. 10-22) to establish the desired anterior guidance.

Contraindications. Patients with poor oral hygiene or a high caries rate are not good candidates for this type of restoration. Young patients with large pulps generally are better served by a resin-retained FPD (see Chapter 26). Often it is not possible to place pinholes of adequate size and length in teeth that are thin labiolingually (Fig. 10-37). Pinledges are con-traindicated on nonvital teeth and when the alignment of the abutment will conflict with the proposed path of withdrawal of the fixed partial denture. Because less surface area is involved in the preparation, pinledges are not as retentive as their less conservative counterparts. Therefore they should not be used when optimum retention is needed.

Maxillary Central Incisor Pinledge. Three designs of pinledge preparations are discussed here: the conventional pinledge (see Fig. 10-34), involving only the lingual surface of the tooth; the pinledge

Pinledge Preparation
Fig. 10-37. Where incisors are thin labiolingually and insufficient dentin remains facial to the casting, appearance is compromised by a pinledge restoration.
Pin Ledge Crown
Fig. 10-38. Pinledge preparation with a proximal slice. The slice provides room for an FPD connector. Sufficient tooth structure should remain between the slice and the pinhole adjacent to it. Note that the junction between pinhole and ledge has been beveled or countersunk.

with a proximal slice (Fig. 10-38); and the pinledge with a proximal groove (Fig. 10-39, A). The latter two can serve equally well as retainers for an FPD; choosing one over the other depends primarily on tooth configuration and the presence or absence of caries. A tooth with a slight proximal convexity can often be prepared successfully with a proximal slice, whereas one with a small carious lesion often lends itself better to the proximal groove variation. The pinledge preparation with proximal slice is described first.

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Responses

  • hannes
    Can FPD be used in opertapered teeth?
    8 years ago
  • fulvus goldworthy
    Where are pinholes placed fpd?
    8 years ago
  • theodoric
    How to splint a tooth with a pin?
    8 years ago
  • Bildad
    What is tooth retainer?
    7 years ago
  • Francesca Cunningham
    What is a pin ledge retainer?
    6 years ago
  • ahti
    What is a pinledge crown?
    3 years ago
  • dina
    How to do crown cutting of central incisor?
    2 years ago
  • NICOLE
    How does pin extend into dentien in pinledge?
    1 year ago

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