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Abfractions and attachment loss in teeth with premature contacts in centric relation: clinical observations.

BACKGROUND
It has been suggested that eccentric occlusal forces may be an etiologic factor for abfraction lesions. It has also been suggested that traumatic occlusal forces may have a damaging effect on the periodontal tissues. The purpose of this study was to determine whether associations were present between premature contacts in centric relation (PCCR), clinical attachment loss, and abfraction lesions.


METHODS
Forty-six subjects were examined. Within subjects, the mean attachment loss was determined for teeth with and without PCCR and for teeth with and without abfractions. In addition, teeth with PCCR (experimental group) were matched with contralateral teeth without PCCR (control group). Comparisons between groups were made with the Wilcoxon signed rank test, Wilcoxon rank sums test, and the Spearman rho correlation coefficient.


RESULTS
The results demonstrated that attachment loss increased with age. Within subjects, teeth with abfraction lesions had significantly more buccal attachment loss than teeth without abfraction lesions (P <0.01). The majority of abfractions and PCCR occurred in premolars. The presence of PCCR had no influence on the appearance of an abfraction lesion or increased attachment loss. Similarly, subjects who exhibited abfractions had similar attachment loss as those subjects without abfraction lesions.


CONCLUSIONS
Within the same patient, teeth with abfractions presented more attachment loss than those without abfractions. However, associations were not demonstrated between PCCR and the presence of abfractions or increased attachment loss. Future studies are needed to improve the knowledge regarding interactions among occlusal factors, attachment loss, and abfractions.