Effects of lower third molar extraction on attachment level and alveolar bone height of the adjacent second molar.

Several conflicting findings have been published in previous literature regarding the effects of impacted third molar extraction on the periodontal health of the adjacent second molar; some authors have shown improvement of periodontal health distal to the adjacent second molar, whilst others have demonstrated loss of attachment and reduction of alveolar bone height. The purpose of this controlled clinical and radiographic study is to evaluate the long-term changes in periodontal health and alveolar bone height distal to the adjacent second molar following extraction of an impacted third molar. This split-mouth design study included 25 patients who underwent extraction of one mandibular impacted third molar (test), whereas the opposite tooth remained intact (control). Pre-operative and current-state panoramic radiographs were than scanned, and alveolar bone height was digitally measured on the distal aspect of the second molar on the test and control sides. Current-state clinical measurements were performed on both sides, and consisted of plaque index, gingival index, periodontal pocket depth, gingival margin position and clinical attachment level. Student's t-test for paired observations was used in order to examine the statistical significance of the differences in clinical parameters between the test and control sides and the differences in alveolar bone height pre- and post-operatively on both sides. Extraction of an impacted third molar resulted in a significant gain of alveolar bone height on the distal aspect of the adjacent second molar on the test side, whereas slight bone loss was noted on the control side. Even though the difference in plaque index between the test and control sides approached statistical significance following extraction, all clinical parameters seem to be unchanged. Further follow-up on clinical and radiological parameters is required for a more profound understanding of the long-term effects of third molar extraction on the periodontal health of the adjacent second molar.

[Parapharyngeal and peritonsillar infection following mandibular third molar extraction].

Numerous complications following impacted third molar extractions have been described previously. Among these are swelling, infection, subdermal hematomas, nerve injuries, injuries to adjacent teeth and mandibular fractures. The parapharyngeal space is a funnel-shaped space with its base located at the base of the skull and its apex near the hyoid bone. It is bounded medially by the superior constrictor muscle and the tonsillar fossa and laterally by the medial pterygoid muscle, the mandibular ramus, the deep lobe of the parotid gland and the posterior belly of the digastric muscle. The junction of the buccinator and superior constrictor muscles at the pterygomandibular raphe forms the anterior border. The posterior border is formed by the vertebral column and the prevertebral muscles. Infratemporal and peritonsillar space infections following third molar extractions are relatively rare because of anatomical barriers that exist in that area, but complications of such infections are considered to be highly severe and sometimes even life threatening. These complications include septic thrombophlebitis of the internal jugular vein, septic aneurysms of the internal carotid artery and mediastinitis. This article presents a parapharyngeal and peritonsillar space abscess resulting from a third molar extraction. Several articles reviewed in this paper revealed similar signs and symptoms in parapharyngeal abscesses. The main radiological finding was soft tissue swelling in the prevertebral area. Cultures have demonstrated Klebsiella pneumoniae as the dominant microorganism in these infections. Early identification and correct diagnosis of parapharyngeal and peritonsillar abscesses are necessary to avoid life-threatening complications that may accompany such infections. Airway control should receive top priority in treatment, followed by extensive surgical drainage and administration of high dose organism-specific antibiotics as well as removal of the source of infection.

Adherence of periodontopathic bacteria to bioabsorbable and non-absorbable barrier membranes in vitro.

Guided tissue regeneration (GTR) techniques are increasingly used for the treatment of periodontal defects, or in conjunction with dental implant procedures. As adhesion of bacteria to barrier membranes used in these techniques may lead to failure, a prerequisite for treatment success is an infection-free healing process. The present study examined the adhesion of 3 periodontal pathogenic bacteria: Actinobacillus actinomycetemcomitans, Treponema denticola and Porphyromonas gingivalis, to 3 barrier membranes: Collagen, (Biomend) PTFE, (TefGen-FD) and e-PTFE, (Gore-Tex). The membranes were incubated with 3[H]-thymidine labeled bacteria, and the number of adherent bacteria was calculated using a scintillation counter. The effect of albumin coating on bacterial adherence to the membranes was also studied. Bacterial adherence to the membranes was further examined by scanning electron microscopy (SEM). The results show that the adherence of all bacterial strains to collagen membranes was significantly higher than to the other membranes tested. Precoating of the membranes with albumin did not change the bacterial adherence significantly. These findings are of importance in evaluating the ability of periodontal bacteria to colonize and infect different types of barrier membranes.