Maintenance of dental implants for the hygienist

Hygienist are now seeing more of their patients with dental implant and this is only going to increase in the future as implant therapy become cheaper. The role of the hygienist has increased in many ways with regards to dental implants. It is important for a hygienist to be able to diagnose peri-implantitis and to be have the knowledge to treat simple to moderate peri-implantitis and to monitor the health of dental implants in the long term as part of the patients regular maintenance.

How do you know when an implant has problems?
It is essential to be methodical when monitoring the peri-implant tissues at review appointments to spot the early signs of peri-implantitis. The clinical markers that are used to assess the presence and severity of inflammation around the implant are:

• plaque and calculus accumulation;
• inflammation of the peri-implant tissues;
• increase in peri-implant probing depths;
• bleeding on probing;
• suppuration from the peri-implant pocket;
• implant mobility;
• radiographic changes.

When probing peri-implant tissues it is essential that a light force is used (0.25 Ncm) to avoid trauma to the tissues. There is a parallel attachment of the junctional epithelium around the implant surface, therefore there is less resistance when probing around the implant. This will result in deeper peri-implant probing depths compared to probing around natural teeth. Peri-implant probing depths of implants placed in sites excluding the aesthetic zone range between 2-4 mm under healthy conditions. In the aesthetic zone where the implant is usually placed deeper, the probing depths are greater than the normal range. It is important to note that most implant systems show evidence of a small amount of marginal bone loss within the first year of function. Smoking has been shown to be a risk factor to affect the long-term prognosis of dental implants therefore it is essential to assess the health of the peri-implant tissues regularly in smokers.

 

What to do if there is bone loss?
If there is on-going bone loss it is important to ascertain the cause. The causes of bone loss are:

• Occlusal overload;
• Bacterial induced inflammation.

Any occlusal overloading needs to be corrected by the implant dentist.
Plaque induced inflammation is initially treated non-surgically but depends on the initial clinical presentation. This involves the removal of dental plaque with or without the use of locally delivered or systemic adjuncts. Lesions with probing depth of 5 mm or more and bone loss of greater than 2 mm would need surgical intervention as recommended by the International Team for Implantology (ITI) consensus report Figure1.

A common cause of plaque induced peri-implantitis is excess cement which has been forced into the tissue when the crown is cemented. If the excess cement is not thoroughly removed by the implant dentist this will induce inflammation of the tissue and possible bone loss.

How to maintain dental implants?
It is important that good oral hygiene is performed to maintain healthy peri-implant tissues. The use of toothbrushes either manual or electric helps to reduce the amount of plaque biofilm. Floss including superfloss and interdental brushes is essential for access interproximally. It is very important that oral hygiene for the patient is not made too complicated thereby prolonging the time required by using too many oral hygiene aids. In the aesthetic zone, a cross over flossing technique can be used (Figs. 2a-f).

A poor flossing technique or no flossing at all can lead to subgingival inflammation of the peri-implant tissues. It is essential that if a cement retained crown is placed that all the cement is removed as subgingival irritants such as excess cement can provoke an acute peri-implantitis which can cause soreness, swelling, bleeding on probing and eventual bone loss (Figs. 3 & 4).

In premolar and molar areas the use of floss or intedental brushes can be easier for the patient in the case of single unit implant, and in fixed bridgework.

Calculus formation on dental implants is very similar to that found on teeth the only difference is that the abutment and the porcelain are very highly polished therefore the calculus is not as tenacious as on a natural tooth. When removing supragingival calculus from the implant crowns it is very important not to use stainless steel scalers as this will damage the titanium surfaces. Therefore it is recommended that one uses a material that is softer than titanium either gold plated or reinforced plastic instruments (Fig. 5). It is very important that an ultrasonic is never used on an implant as this will heat up the implant and could kill the bone that helps integrate the implant.

When pocketing has been noted then using the CIST protocol will help treat the majority of peri-implantitis cases. Below is an example of an UR2 with 8 mm pocketing, the site was treated non-surgically with local delivery antimicrobials and with the patient using chorhexidine gel with the largest interdental brush (Figs. 6a-c). At the 2 week review the pocketing associated with the UR2 has reduced to 5 mm with simple non-surgical therapy any further intervention will need to reviewed by the implant dentist.

Conclusion
Good oral hygiene performed by the patient has a significant affect on the stability of the marginal bone around dental implants. Therefore regular hygienist appointments are necessary to ensure that your patients are maintaining a high standard of oral hygiene around their dental implants.