Local contributing factors play a role by increasing the risk for developing a periodontal condition or increase the severity of an existing condition in a variety of ways. One way is they contribute to an increase in plaque/biofilm retention. An example of this would be an over hanging margin on a Class II restoration or a Class IV composite restoration at or below the gingival margin. Another way they contribute is to cause direct damage to the periodontium. An example of this would be a partial denture impinging on the periodontium or trauma from misuse of oral health aids (Nield‐Gehrig and Willmann 2016).

Biologically sound and functioning dentition as an unmet human need may be caused by restorations that are poorly contoured, have open margins, or overhanging margins. Following are more detailed examples of local contributing factors:

• Figure 2.6.1 shows plaque accumulation around a crown margin. Note the inflammation around the gingival margin. The crown could be bulky or have an open margin. After dental hygiene therapy a re‐evaluation appointment to determine the need for further care is recommended.
• Figure 2.6.2 shows calculus accumulation on the root surface of anterior crowns. Note the crowns are fused leading to difficulty in completing oral hygiene self‐care. The distal margin of the lateral incisor may have an open and overhanging margin. These restorations contain many of the contributing factors for plaque retention and difficulty in cleaning.
• Figure 2.6.3 shows gingival inflammation around anterior crown margins. It appears there is minimal plaque accumulation. The margins could be bulky or it could be a tissue reaction to the dental biomaterials used in the fabrication of the crowns.
• Figure 2.6.4 shows a broken tooth/restoration with plaque accumulation. Planned interventions would include dental care to replace the restoration. Pain should also be a consideration when developing a dental hygiene diagnosis and care plan.
• Figure 2.6.5 shows crowding on the mandibular incisors. Crowding is a local contributing factor in different ways. One way is difficulty for the patient to conduct self‐care and plaque removal. Another way is root proximity contributing to difficulty in root debridement procedures.

Plaque accumulates for many reasons. One reason may be the patient’s ability to effectively perform self‐care. Another may be the specific dental material used such as a large fill composite that is rough and difficult to polish. Margins that are bulky or have overhangs provide a nexus for plaque accumulation. Broken teeth or restorations have rough margins and lead to plaque accumulation. Realistic goals of educating the patient as to the reason further dental treatment are required as well as oral hygiene care around the restoration. The clinician can use both biologically sound and functioning dentition due to the crown margins being bulky or ill‐fitting or skin and mucous membrane integrity due to gingival inflammation. Dental hygienists can perform margination techniques to remove overhangs on Class II restorations and polish restorations that are rough and plaque retentive. Other than these adjunct interventions a referral for dental services to address concerns must be included.

A dental hygiene diagnosis of integrity of skin and mucous membrane is used to plan for dental hygiene care related to inflammation and calculus accumulation. The evidence of plaque or calculus accumulation accompanied by bleeding, reddened, and edematous gingiva allows for a care plan of nonsurgical periodontal therapy. Examples of these are shown in Figures 2.6.4 and 2.6.5.

• Figure 2.6.6 shows calculus accumulation on the lingual of the mandibular incisors with associated edematous papilla and rolled margins. Calculus as a local contributing factor is a plaque retentive factor.
• Figure 2.6.7 shows heavy subgingival calculus leading to plaque retention and difficulty performing oral hygiene self‐care.

Although calculus is not the cause of periodontal disease, it plays a significant role in increasing the risk for development or exacerbation of an existing condition. Plaque accumulation is associated with calculus. Mature plaque that covers calculus can increase the pathogenicity. Interventions include patient education regarding the removal of the deposits and disease progression. Oral hygiene instructions to reduce plaque accumulation and address the patient’s self‐care behaviors can also be employed. Nonsurgical periodontal therapy and adjunctive therapies tailored to the individual patient should also be included.

The American Academy of Periodontists added the addition of a category on “Developmental or Acquired Deformities and Conditions” to address localized tooth‐related factors. Tooth anatomic factors, dental restorations/appliances, root fractures, and cervical root resorption are specifically listed. They have been included as important modifiers of the susceptibility to periodontal diseases. Addressing these tooth‐related factors can affect the outcomes of treatment (Armitage 1999).

Recognizing the risk factors and addressing the patient’s unmet human needs are the initial steps in the process of care. Developing a dental hygiene care plan and interventions that include dental referrals is essential to the outcomes of treatment when dealing with local contributing factors.