What is the hygienist’s role in restoratively driven implant complications?

Implants have proven to be an excellent treatment option for our patients. However, there is still some confusion that exists when it comes to the long-term assessment of these sophisticated medical devices. It is important to address this and to understand the role of the team members. The team members include the surgical dentist, restorative dentist, dental assistants, dental laboratory technician, dental hygienist, and the patient.

All members of the team should understand what to look for and how to detect potential complications. The dental hygienist will have the most important role in long-term maintenance and should be able to recognize what signs and symptoms to look for. He or she should also understand when surgical intervention is required. The other team members will depend on the dental hygienist for any information that may be pertinent to the long-term success of the implant.

The high survival rate of osseointegrated implants is well documented, but if an implant does fail it is generally due to bacterial infection, a poorly designed prosthesis, or over-extended occlusal force (occlusal overload) (1). Studies are now showing that only a small percentage of implant failures are due to occlusal overload (2), and the majority of the late failures of already integrated implants can be attributed to peri-implant infections and cement residue. Other signs of a failing implant are pain, mobility, and unacceptable bone loss.

This chapter will focus on the complications of peri-implant disease (mucositis and implantitis) (refer to Figure 7.1A) and includes a special section by Alfonso Piñeyro on cement-induced peri-implant disease; see Figure 7.1B: what it is, how it develops, and the role of the dental hygienist in detection and diagnosis.

Peri-implant disease

Research shows that the mucosal peri-implant tissues surrounding the exposed portion of a dental implant contain the same bacterial flora as the periodontium. Peri-implant tissues cascade from peri-mucositis to peri-implantitis in a similar progression of gingivitis to periodontitis around natural teeth (1) and are collectively known as peri-implant disease (i.e., mucositis and peri-implantitis) (2).

Peri-implant mucositis, similar in nature to gingivitis caused by bacteria, occurs in approximately 80% of patients who have implants placed in 50% of implant sites (3). It is manifested by redness and inflammation in the soft tissue around the implant, no bone loss, and is reversible. Improved oral hygiene and professional implant in-office maintenance prophylaxis by a hygienist can reverse mucositis to a healthy state.

Peri-implantitis, or bone loss around an implant, can be induced by stress, bacteria, or both. Stuart Froum states, “The diagnosis of peri-implantitis includes probe depths (PD) of 5 mm to 6 mm or greater, bleeding on probing, and bone loss greater than 2 mm to 3 mm around the implant. Treatment depends on the extent of PD and bone loss” (4).

Peri-implantitis is very similar to periodontitis, with significant inflammation and exu­date. With peri-implantitis, a sulcular crevice deepens around the implant to allow bacteria to migrate down, causing bone loss that can be irreversible. On a radiograph, radiolucency in a “saucer” shape around the implant can occur in 28–56% of implants after 5 years at 12–40% of implant sites (3). Risk factors include poor oral hygiene, smoking, poorly fitting restorations, retained cement from cement-retained implant restorations, and poorly controlled diabetes (5).

Peri-implantitis is generally not painful and patients may not even be aware that they have an infection or that anything is wrong with their implant. Hygienists need to take note that there is also a 28.6% increase of peri-implantitis in patients that have had chronic periodontal disease compared with healthy patients at 5.8% (6, 7). This is an excellent reason to motivate patients to continue on regularly scheduled implant maintenance appointments. Monitor your periodontal disease patients closely who have chosen implant therapy and keep these patients on a more frequent implant maintenance schedule (7).

The diagnosis of peri-implantitis is based on probing depths of 5–6 mm or greater, bleeding on probing, and bone loss greater than 2–3 mm around the implant. Treatment depends on the extent of probe depth and the radiographic bone loss. That is why it is recommended that at every implant maintenance appointment the hygienist or dentist probe around an implant (4; see Figure 7.2).

If the implant has a probing depth of 5–6 mm or greater, bleeding, and/or a presence of exudate, a radiograph(s) should be taken to assess the implant and evaluate for bone loss.

Record any signs of inflammation or bleeding upon probing surrounding a dental implant exposed to the oral environment. Also record any clinical symptoms of pain or mobility. Radiographs should also be taken if these symptoms are present to evaluate for bone loss; however, when a failing implant becomes mobile, it is considered a failure and may often need to be removed and replaced with a new implant when conditions warrant.

Check for pocket depth, inflammation, and bleeding, and/or palpate the ridge for signs of infection; see Table 7.1 and Table 7.2. Refer to Chapter 6 for more specifics on assessing, identifying, and monitoring for implants.

Cement residue complication

Contributed by Alfonso Piñeyro, DDS