Prerequisites

Prerequisites for an implantation is the exclusion of contraindications.
Contraindications include patients at risk, severe general illnesses (e.g., systemic bone diseases, osteoporosis, diabetes), lack of motivation and cooperation, lack of oral hygiene, unrefurbished remaining teeth, insufficient bone in the law jaw canal or maxillary sinus, or post-radiation condition.

Implant preexamination

A test determines whether there is sufficient bone available for the implant at the planned site. This includes the evaluation of a plaster model of the jaw, measurements of mucosa thickness as well as X-ray images or computertomographical recordings. Transparencies with various implant forms, positioned over the X-ray images to determine the optimum implant position, are available to aid X-ray based implant planning. The length and thickness of the implant can then be selected. Implants may not injure or jeopardise any important anatomical structures such as maxillary sinuses, adjacent teeth, nerves or other implants. The position of the implant bed and the alignment of the implant axis can be verified with a special template during the operation.
Imaging diagnostic procedures:

• Dental film for individual implants.
• Orthopantomogram:
  In the lower jaw: assessment of the course of the nerve canal.
  In the upper jaw: assessment of the border of maxillary sinuses and the nasal floor.
• Lateral teleradiography:
  Assessment of the height of the alveolar process in the frontal tooth region of the upper and lower jaw.
• Computer tomography:
  Digital, three-dimensional displays are possible to determine the direction, position and diameter of the implants.

After anaesthesia, a mucoperiosteal flap is folded away across the planned bone region. The implant's position is specified with a drilling template and a thin pilot drill. The bone boring is prepared with various mills which will have to be accurately coordinated with the size of the implant. Special externally and internally cooled mills are available to this effect. After the bone boring has been thoroughly rinsed with saline solution, the sterile implant is screwed or plugged into the bone, whereby the surface must not be bacterially contaminated. The mucosa is then carefully sutured back over the implant.

During the healing process of the bone, known as osseointegration, woven bone will initially accumulate at the implant surface and mature into lamelliform bone within the course of a year, while a gingival rim is formed at the passage point of the implant as it would in a natural tooth. Osseointegrated implants have no parodontium and are thus rigidly connected to the bone.

However, fibroossary healing may occur without osseointegration. These cases are assessed as failures, as implants healed in the connective tissue rapidly mobilise and are lost quickly due to marginal infection.