Dental Implants

Definition

A Dental Implant (also known as an endosseous implant or fixture) is a surgical device used to replace missing teeth by providing a stable foundation for fixed or removable replacements. Unlike traditional bridges, implants do not require the alteration of adjacent teeth.

Biological Principles

The fundamental principle of modern dental implants is Osseointegration.

Discovery: Discovered by Per-Ingvar Brånemark, who observed that bone would bond nearly permanently to titanium.
Process: Following surgical placement, osteoblasts (bone-forming cells) grow directly onto the microscopic roughness of the implant surface.
Stability:
- Primary Stability: The mechanical "grip" of the implant in the bone immediately after surgery.
- Secondary Stability: The biological bond formed through healing.

Components

A complete implant restoration consists of:

Implant Body: The portion that resides in the bone. Most are made of Grade 4 Titanium or Titanium Alloy (Ti-6Al-4V).
Abutment: The interface that connects the internal screw of the implant to the oral environment.
Restoration: The Crown, Bridge, or Denture that is either screwed or cemented to the abutment.

Surgical Procedure

The treatment is typically divided into phases:

Treatment Planning: Utilization of CBCT and digital scans to assess bone volume and vital structures.
Implant Placement: A hole is prepared in the bone (osteotomy) using sequential drills under irrigation, and the implant is inserted.
Healing (Stage I): A period of 3–6 months for osseointegration.
Restoration (Stage II): Placement of the abutment and the final prosthetic.

Clinical Indications

Single Tooth Replacement: To restore a gap without "sacrificing" healthy neighboring teeth.
Multiple Teeth Replacement: Supporting an implant-supported bridge.
Full Arch Rehabilitation: Concepts such as All-on-4®, where a full set of teeth is supported by four strategically placed implants.

Contraindications and Risks

Absolute: Recent myocardial infarction, active high-dose bisphosphonate therapy (IV), or uncontrolled systemic disease.
Relative: Heavy smoking, uncontrolled diabetes, and bruxism.
Failure: May occur due to infection (Peri-implantitis) or lack of primary stability.