The technique for insertion of the implant depends largely upon the system being used. In general, the final bone preparation site diameter is slightly smaller than the implant. The size of the site can be adjusted according to bone quality or
density. In poor quality bone the site can be made relatively smaller to produce compression of the surrounding bone on implant insertion which will improve the initial stability. In dense bone the site has to more closely match the size of the implant. In bone with relatively poor medullary quality, where initial stability may be difficult to achieve, it is often advisable to secure the implant at each end in cortical bone (bicortical stabilisation) providing anatomical structures, length of implants and ability to provide adequate cooling allow this.
The implant is supplied in a sterile container, either already mounted on a special adapter or unmounted necessitating the use of an adapter from the implant surgical kit. In either case the implant should not touch anything (other than a sterile titanium surface) before its delivery to the prepared bone site. Screw shaped implants are either self tapped into the prepared site or inserted following tapping of the bone with a screw tap. Cylindrical implants are either pushed or gently knocked into place. The installation of the implants should be done with the same care as the preparation of the site by maintaining the cooling irrigation and placing the implant at slow speeds. Screw shaped implants and tapping of sites are performed at speeds of less than 25 rpm and a torque limit of up to 40 N cm (Fig). Following placement the head and inner screw thread of the implant is protected with a 'cover' or closure screw (Fig.).
density. In poor quality bone the site can be made relatively smaller to produce compression of the surrounding bone on implant insertion which will improve the initial stability. In dense bone the site has to more closely match the size of the implant. In bone with relatively poor medullary quality, where initial stability may be difficult to achieve, it is often advisable to secure the implant at each end in cortical bone (bicortical stabilisation) providing anatomical structures, length of implants and ability to provide adequate cooling allow this.
The implant is supplied in a sterile container, either already mounted on a special adapter or unmounted necessitating the use of an adapter from the implant surgical kit. In either case the implant should not touch anything (other than a sterile titanium surface) before its delivery to the prepared bone site. Screw shaped implants are either self tapped into the prepared site or inserted following tapping of the bone with a screw tap. Cylindrical implants are either pushed or gently knocked into place. The installation of the implants should be done with the same care as the preparation of the site by maintaining the cooling irrigation and placing the implant at slow speeds. Screw shaped implants and tapping of sites are performed at speeds of less than 25 rpm and a torque limit of up to 40 N cm (Fig). Following placement the head and inner screw thread of the implant is protected with a 'cover' or closure screw (Fig.).
Fig.: Mylohyoid muscle will maintain bone along its attachment on the lingual aspect of the mandible. There is frequently a significant depression just below this, and,if implant position and angulation do not compensate, lingual perforation may result. a+b apparent bone height on radiograph; a, actual bone height.
The mucoperiosteal flaps are carefully closed with multiple sutures either to bury the implant completely or around the neck of the implant in non-submerged systems. Silk sutures are satisfactory and others such as PTFE or resorbables (e.g., vicryl) are good alternatives.
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