Dental Implant Care and Oral Hygiene Practices

First, a trained clinical research dental assistant interviewed the participants and showed them pictures of oral hygiene aids so that the participants could answer the survey questions accurately. Subsequently, a periodontal examination, dental prophylaxis, and oral hygiene education were performed. Participants with active diseases e.g. caries, periodontitis, or peri-implantitis were referred for further management. The following clinical parameters were recorded during the examination:

• Probing depths at 6 sites around the implant (mesiobuccal, midbuccal, distobuccal, distolingual, midlingual and mesiolingual)
• Plaque index (Silness & Loe 1964) at 4 sites around the implant (mesial, buccal, distal and lingual)
• Amount of keratinized mucosa at the implant site
• Characteristics of the implant crown:

• Type of implant crown (screw- or cement-retained) and
• Position of crown margins (supra-, equi- or sub-gingival)
• Reason(s) for tooth loss
• Diagnosis of peri-implant health

• Normal
• Mucositis, defined as 3 or more bleeding points per implant
• Peri-implantitis, defined as implant thread exposure that was either clinically visible or detectable with a periodontal probe.

Inclusion criteria

• English speaking patient
• Aged 21 years old or above
• Received at least 1 implant-supported single crown from NUH in the year 2007-2011 (in functional loading for at least 5 years)

Exclusion criteria

• Implant is used to restore overdentures or multi-unit restorations such as splinted crowns, fixed partial dentures, and cantilevers.
• Pregnant/lactating women
• Parkinson's disease or any other debilitating diseases
• Physical or mental disabilities that may impair oral hygiene practices
• Poorly controlled diabetes
• Heavy smoker (10 or more cigarettes per day)
• Radiation therapy in head and neck region
• HIV, TB, hepatitis or other infectious diseases
• Drug and alcohol abuse