Читать книгу Periodontics - Fernando Suarez - Страница 115

Tooth crowding, crossbite, extreme overjet/overbite, and malposition are very common forms of malocclusion^235,236 and often associated with worsened periodontal conditions.^237–239 Studies evaluating the prevalence of crowding and periodontal diseases had reported values ranging between 58% and 95%, and their presence is seemingly influenced by age.^240–243

Different definitions and grading scores have been proposed to assess crowding for periodontal purposes.^226,244,245 Van Kirk developed a scoring index to examine malalignment.²⁴⁴ Score 0 was given to an ideal alignment with no deviation from the ideal arch line projected through contact areas. Minor and major malalignment conditions were also assessed by the degree of rotation and displacement. Score 1 includes situations where rotation is less then 45 degrees and malalignment less 1.5 mm. Score 2 includes situations of rotation exceeding 45 degrees and displacement equal to or more than 1.5 mm.

To date, it remains controversial whether tooth position–related factors exert a significant impact on the periodontium using oral hygiene as a confounding factor.^{226,246–255} Early studies showed a correlation between crowding and increased loss of clinical attachment, plaque accumulation, and gingival inflammation.^{241,256–258} On the other hand, other studies reported that crowding has no effect on periodontal health.^{226,235,240,259–261}

Results from a cross-sectional study among 154 army recruits concluded that tooth malposition does not enhance periodontal breakdown; however, it decreases the ability for optimal oral hygiene habits.²⁴² Ultimately, Ingervall et al demonstrated that crowding did not favor plaque accumulation or extent of gingival inflammation in an experimental gingivitis model.²⁴⁵

Because tooth crowding is not a causal agent for the initiation of periodontal disease, it must be considered in conjunction with biofilm as a contributing factor for periodontal breakdown.²⁶² Hence, individuals with poor plaque control and crowding might be more susceptible to attachment loss.