Ten Key Points for Clinical Follow-Up of Dental Implants

Dental implants serve as artificial roots to replace missing teeth. Their stability and health are crucial for chewing function and oral aesthetics. However, mechanical or biological complications can lead to implant failure. To ensure long-term stability, following up every 3-4 months in the first year after implant treatment is recommended. An annual check-up is advised if the implants are stable and free of inflammation and complications. Regular follow-ups allow dental professionals to effectively manage the health of implants, address issues promptly, and enhance the long-term stability and success rate of implants.

This article briefly outlines ten key points for implant follow-up examinations, helping you understand how to check implants and detect potential problems, thus improving early detection of peri-implant mucositis, peri-implantitis, and long-term prognosis.

Ⅰ Patient Satisfaction

The clinical evaluation by doctors and patients' subjective feelings may not always align. Therefore, it is necessary to record whether the patient is satisfied with the prosthesis and if there are any symptoms or discomfort. Factors affecting patient satisfaction include the prosthesis itself (shape, color, and cleaning ability) and the aesthetics of the soft tissues (gingival recession, black triangles, metal exposure, etc.).

Ⅱ Peri-Implant Tissue Inflammation

Any signs of inflammation and pain around the alveolar tissue of the implant indicate the presence of peri-implant mucositis or peri-implantitis, requiring further examination.

Diagnosis of Peri-Implant Mucositis

Redness, swelling, and bleeding around the implant mucosa, with or without suppuration upon probing.

Diagnosis of Peri-Implantitis

• In the presence of baseline radiographs (taken during initial implantation and loading) and periodontal pocket depth measurements, a positive BOP (Bleeding on Probing) and/or abscess accompanied by increased pocket depth and bone loss can diagnose peri-implantitis.
• In the absence of baseline radiographs, the following clinical findings suggest possible peri-implantitis:

1. Bleeding on probing and/or suppuration;
2. Probing depth ≥6 mm;
3. Bone level decrease ≥3 mm compared to the implant neck.

Ⅲ Oral Hygiene

Poor oral hygiene is a significant indicator of potential future peri-implant inflammation. The accumulation of dental plaque on the implant surface can lead to peri-implant mucositis, which, if untreated, can progress to peri-implantitis.

Ⅳ Bleeding on Probing

Probing with light force (0.20-0.25 N) will not damage the peri-implant tissues. It is recommended to check at least once a year. Use a plastic or metal probe to gently probe six points or around the implant (Figure 1).

Figure 1: Shows BOP around an implant crown on the upper right central incisor after gentle probing

Ⅴ Probing Depth

The pocket depth around a healthy implant is typically less than 5 mm. Recording the baseline probing depth at the time of prosthesis placement is crucial for future comparison and diagnosis of implant diseases.

Ⅵ Occlusion

Implants lack the periodontal ligament and the buffering capacity of natural teeth, making occlusal function assessment critical for evaluating implant prostheses. Occlusal evaluation should include static and dynamic functions. Static occlusion refers to the relationship of the implant prosthesis in maximum intercuspation, while dynamic function includes protrusive and lateral movements. For single-tooth implants, avoid occlusal contacts in lateral movements; for full-mouth restorations, ensure balanced and stable occlusal contacts.

When assessing the occlusion between the implant crown and opposing natural teeth, Shimstock foil can be used. First, have the patient bite lightly; the foil should pass between the implant prosthesis and the opposing natural tooth. Then, have the patient bite firmly; the Shimstock foil should maintain contact. In cases of occlusal overload, an occlusal guard may be necessary. Additionally, check natural teeth for signs of wear and changes.

Figure 2: Shimstock foil passing through the contact between the upper right central incisor implant crown and the opposing natural tooth in maximum intercuspation

Ⅶ Mobility

Mobility can indicate looseness of the implant itself or its components (e.g., connecting screw, crown, or bridge). Use a mouth mirror handle to gently press on the implant crown or lightly feel with your fingers (Figure 3). Implant mobility usually causes discomfort in surrounding tissues, while loosening of components might be asymptomatic.

Figure 3: Checking the mobility of the upper right central incisor crown with a mouth mirror and probe handle

Ⅷ Interproximal Contacts

Poor interproximal contacts can lead to food impaction, caries, gingivitis, peri-implant mucositis, and peri-implantitis in adjacent natural teeth. Check contact points using clinical photos and dental floss or 12μm occlusal paper between contact points.

Ⅸ Integrity and Emergence Profile of Prosthesis

The integrity of the prosthesis is crucial, with porcelain chipping being the most common complication, occurring in 13.5% of cases. For screw-retained dentures, the incidence of screw hole repair material falling out is 5.4%. An emergence angle greater than 30° increases the risk of peri-implantitis.

Figure 4: Poor emergence profile of the implant crown (red arrow) makes cleaning difficult, preventing complete tissue assessment, BOP detection, and pocket depth measurement. A smooth emergence profile (black arrow) is relatively easy to clean and assess

Figure 5:

(a) An X-ray taken during a follow-up visit shows the poor morphology of the implant crown, leading to bacterial accumulation.

(b) An X-ray confirming the correct position of the adjusted implant crown to prevent peri-implant diseases.

Ⅹ Radiographic Examination

Radiographic examinations are recommended immediately after implantation and annually thereafter to diagnose peri-implant diseases. Parallel imaging is preferred, typically recording the distance from the mesial and distal points of the implant top to the bottom of bone resorption.

Ⅺ Conclusion

As implant restorations become an increasingly common choice for dental defects/missing teeth, implant follow-up and maintenance have become essential parts of a dentist's daily work. Through convenient, quick, and comprehensive examinations and diagnoses, early detection and timely treatment of problems can maximize the long-term success of implants, improve patient satisfaction, and enhance the professional image and reputation of the dentist.