Operative tips 287

Fig. 7-73. An internal clip bar arrangement. A, The palateless denture with semicircular clip attachments, which is fitted over the dolder bar supporting the screw type implant (B). C, The arrangement permits a suitable palateless denture.

vertical return to passive position. They also require only a simple crown preparation (Fig. 7-69). The Crismani attachments allow vertical resilience, hinge action, bilateral balance, a complete return to passive position, and snap lock retention (Fig. 7-70).

Resilient Gerber attachments are also often used as stress-breakers (Fig. 7-71). These may be combined with any type of abutment instead of only distal extensions. These Gerber attachments are used for tissue-supported cases and are often used with the dolder bar (Fig. 7-72). Another useful attachment is the internal clip bar (Fig. 7-73).

SUTURING

The implantologist must be skilled in suturing because a great many implant procedures require opening and closing the tissues. The way in which the tissues have been closed over an implant site or secured around an implant post plays a major role in healing. Choosing the correct materials and the most advantageous suturing technique is a basic skill in implantology, a skill that can only be improved with practice.

Suture materials

The basic suturing materials are surgical ligature material and suturing needles. There are two kinds of ligature material, absorbable and nonabsorbable.

Absorbable ligature materials. These ligature materials are absorbed or digested by the body cells and fluids during healing and are most frequently used for suturing bleeding areas or for closing muscle or fascia. Absorbable ligature materials include ribbon gut, kangaroo tendons, kangaroo bands, fascia lata, and catgut, which is by far the most popular.

The catgut used today is actually derived from the small intestines, or casings, of sheep. The suture material is made from only the intestinal submucosa, which is a thin strong network of microscopic collagenous fibers. The submucosa is stripped out and rolled into a strand. Processing increases in orientation of the fibers, strengthening the strand. The strand is then stretched and spun with from one to four other strands under controlled tension. The more strands twisted together, the larger the diameter and the greater the number of twists per inch of the material.