Examining the peri-implant tissues
Oral hygiene
Inadequate oral hygiene around an implant and its restoration can contribute to inflammation and peri-implant problems.115 Some fixed restorations are extremely challenging to assess and to clean for both clinician and patient. Reduced manual dexterity in older patients may also contribute to increased plaque retention around a restoration. In these cases, personalised oral hygiene instruction will be required and increased frequency of maintenance support to counter the increased risk should be considered.
Probing
The tissues surrounding implants are not connected to the implant surface in the same way as those surrounding teeth and are less resistant to probing (see figure: Anatomical differences between tooth and implant). In addition, the depth of the crevice around implants is variable and dependent on the depth of placement of an implant and the thickness of the overlying tissues. Therefore, the probing depth around healthy implants can be variable.
The EFP Prevention and treatment of peri-implant diseases guideline10 recommends assessment of peri-implant health at each clinical examination, including assessment of probing depths and bleeding on probing (see figure: Probing around implants).
Clinical image showing healthy peri-implant tissue around the implant at 11 and bleeding on probing around the implant at 21.
When examining the peri-implant tissues, gentle probing pressure is advised and probing depth, if recorded, should be measured from a fixed landmark. A marked increase in probing depth from baseline fixed points, together with suppuration and bleeding, suggests the presence of peri-implant inflammation and infection. In the absence of progressive bone loss, these signs indicate peri-implant mucositis. If progressive bone loss is present, then a diagnosis of peri-implantitis can be made.
Although plastic probes are available (see figure: Implant probe), there is no evidence that the use of metal probes is detrimental to the tissues around the superstructure or implant.
It is not appropriate to apply the Basic Periodontal Examination (BPE) for the assessment of implants.
Plastic graduated probe suitable for probing around dental implants.
Calculus
Supramucosal calculus is more common around implants than submucosal calculus and this is generally easier to remove than the calculus attached to teeth. However, if the implant threads are exposed, plaque biofilm and calculus removal from them can be difficult. Soft supramucosal deposits can be removed using a rubber cup and an implant-specific prophylactic paste or an air polisher and glycine powder. Calculus should be removed using standard techniques while making every effort to minimise damage to the restoration and implant surface.
Although non-metal curettes and tips for sonic and/or ultrasonic instruments are available, the use of metallic instruments or tips is not contra-indicated and their use is not detrimental to the tissues around the superstructures or implants when used correctly.
Radiographs
The clinical team placing the implant should provide a radiograph which shows bone levels around the implant at the time the superstructure is connected. The clinical team responsible for maintenance should take a new periapical radiograph, using the long cone paralleling technique, showing the bone crest around the implant one year later. This radiograph obtained at one year, when compared to the radiograph at superstructure connection, will show the degree of adaptive remodelling. A stable landmark, such as the implant shoulder or implant threads, on the one year radiograph becomes the baseline from which bone loss around the implant can be monitored in the long term.
If a patient presents to a new clinical team with no radiographic record, the clinical team should initially try to obtain baseline radiographs, with the patient’s consent. If this is not possible, then radiographic assessment of the implant(s) should be performed.