Collagen metabolism in pericoronitis.

Abstract

Abstract. Collagen metabolism of the operculum overlying the crown of the mandibular third molar was studied in patients with and without pericoronitis. The tissues were classified as (J) overlying unerupted lower 3rd molars, (II) the operculum overlying partially erupted lower 3rd molars, (III) same as (II) except in patients having a positive past history of pericoronitis, and (IV) same as (II) except in patients exhibiting signs and symptoms of active infection. All classes of tissue were found to contain 81–82 % water. The total protein recovered in these tissues increased progressively from class I to class IV due to an effect on the acid‐soluble fraction. The total collagen levels, on the other hand, decreased. This decrease was similar for class II and III tissues, while the greatest loss of collagen was demonstrated in class IV tissues. All four classes of tissue contained essentially the same concentration of acid‐soluble collagen. The loss of collagen appeared to parallel an increased collagenolytic activity of these tissues in culture. Collagenolytic activity of class II and HI tissues was increased and class IV tissues exhibited the greatest increase. The overall changes in protein and collagen metabolism in these tissues due to partial tooth eruption and subsequent infection appeared similar to those observed by others in extra‐oral connective tissues subjected lo injury and inflammation. Changes in collagen metabolism could not be correlated with the reported increased susceptibility to pericoronitis of previously infected tissues. The only change observed in these tissues was a higher proportion of acid‐soluble protein.