5-year follow up of periodontal intraosseous defects treated by root planing or flap surgery

Intraosseous, periodontal defects in 12 subjects initially treated by root planing alone (21 defects) or by flap surgery (21 defects) were monitored during a 5-year postoperative interval. Maintenance therapy during this interval was limited to reinforcement of oral hygiene and tooth polishing every 6 months. No subgingival instrumentation was performed at the defect sites. Longitudinal clinical measurements demonstrated that surgically-treated lesions responded with somewhat more reduction of probing depth and more gain of probing bone level than root-planed lesions. Mean gains of probing attachment level were similar for the 2 treatments. Some relapse of the clinical conditions could be observed towards the end of the 5-year observation interval compared to the results at year 1 and year 2. However, the majority of defects subjected to either treatment showed 60-month recordings of probing attachment and probing bone levels equal to or slightly improved compared to those at baseline. Counts from cultures of subgingival, microbial samples were obtained at 42, 48 and 60 months. No significant difference between the 2 therapies was observed for the investigated groups of micro-organisms.     

On the inability of root debridement and periodontal surgery to eliminate Actinobacillus actinomycetemcomitans from periodontal pockets

In a previous study, we observed that root debridement was inefficient in eliminating Actinobacillus actinomycetemcomitans from adult periodontitis lesions. The present report describes the effects on A. actinomycetemcomitans of subsequent treatments of 6 patients that had at least 2 separate sites still harboring A. actinomycetemcomitans 6 months following debridement. 1 site or more in each individual was treated with renewed root debridement and at least 1 other site was treated by surgical excision of the gingival tissue. The results indicated that retreatment with either repeated root debridement or with surgical excision of the gingival tissue was not more effective in eliminating A. actinomycetemcomitans than initial debridement. The possible reasons for this limited therapeutic effect on the subgingival presence of A. actinomycetemcomitans are discussed.     

Healing after treatment of periodontal intraosseous defects

84 periodontal intraosseous defects treated with mucoperiosteal replaced flap surgery and citric acid root conditioning were used to study the relationships between various defect characteristics and the healing response as expressed by change of probing attachment level, change of probing bone level and residual probing depth. More gains in probing attachment and probing bone levels were observed in deep defects than in shallower lesions. Other defect characteristics showed weak or no correlations to defect fill. The findings of this study seem to indicate that the outcome of treatment of intraosseous defects may be difficult to predict based upon evaluation of defect characteristics.     

Comparison between the Klemetti index and heel DXA BMD measurements in the diagnosis of reduced skeletal bone mineral density in the elderly

Osteopenia/osteoporosis affect many elderly people and might not be detected until symptoms of fractures occur. Early detection of osteopenia/osteoporosis is important and would allow preventive measures and treatment. Access to screening for osteopenia/osteoporosis is often limited, whereas panoramic radiography is commonly used in dentistry. The aim of this study was to determine the validity of the Klemetti index (KI), measured on panoramic radiographs, in the diagnosis of osteopenia/osteoporosis as defined by a bone mineral density (BMD) measurement below –1.5 standard deviations (SDs) of a community based sample. In total, 211 consecutive participants (102 men and 109 women) 60–96 years in the SNAC–Blekinge study (Swedish National Study on Ageing and Care) underwent bone densitometry [by dual-energy X-ray absorptiometry (DXA)] of both heels. A panoramic radiograph was taken of each participant, and mandibular cortex on a panoramic radiograph was classified as 0 or normal (even and sharp endosteal margin), 1, moderately eroded (evidence of lacunar resorption or endosteal cortical residues), or 2, severely eroded (unequivocal porosity). From logistic regression, the odds ratio of having a BMD measurement below –1.5 SD was 8.04 (95% CI 2.39 to 27.12, P<0.001) in the osteopenic (KI category 2), compared with the normal group (KI categories 0 and 1). Receiver operating characteristic (ROC) curve analysis was used to measure the validity of the KI indicating osteopenia (KI category 2) in predicting reduced BMD. This point provided a sensitivity of 50% and a specificity of 89%. Positive and negative predictive values were 21% and 97%, respectively. There were 87% correctly classified subjects. The area under the ROC curve was 0.64. The present study demonstrated that a negative finding (KI category <2) is highly predictive of the absence of osteopenia/osteoporosis as defined by the DXA measurements.     

Modification of cystatin C activity by bacterial proteinases and neutrophil elastase in periodontitis.

AIM: To study the interaction between the human cysteine proteinase inhibitor, cystatin C, and proteinases of periodontitis associated bacteria. METHODS: Gingival crevicular fluid samples were collected from discrete periodontitis sites and their cystatin C content was estimated by enzyme linked immunosorbent assay (ELISA). The interaction between cystatin C and proteolytic enzymes from cultured strains of the gingival bacteria Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans was studied by measuring inhibition of enzyme activity against peptidyl substrates, by detection of break down patterns of solid phase coupled and soluble cystatin C, and by N-terminal sequence analysis of cystatin C products resulting from the interactions. RESULTS: Gingival crevicular fluid contained cystatin C at a concentration of approximately 15 nM. Cystatin C did not inhibit the principal thiol stimulated proteinase activity of P gingivalis. Instead, strains of P gingivalis and P intermedia, but not A actinomycetemcomitans, released cystatin C modifying proteinases. Extracts of five P gingivalis and five P intermedia strains all hydrolysed bonds in the N-terminal region of cystatin C at physiological pH values. The modified cystatin C resulting from incubation with one P gingivalis strain was isolated and found to lack the eight most N-terminal residues. The affinity of the modified inhibitor for cathepsin B was 20-fold lower (Ki 5 nM) than that of full length cystatin C. A 50 kDa thiol stimulated proteinase, gingipain R, was isolated from P gingivalis and shown to be responsible for the Arg8-bond hydrolysis in cystatin C. The cathepsin B inhibitory activity of cystatin C incubated with gingival crevicular fluid was rapidly abolished after Val10-bond cleavage by elastase from exudate neutrophils, but cleavage at the gingipain specific Arg8-bond was also demonstrated. CONCLUSIONS: The physiological control of cathepsin B activity is impeded in periodontitis, owing to the release of proteinases from infecting P gingivalis and neutrophils, with a contribution to the tissue destruction seen in periodontitis as a probable consequence.     

Clinical approaches to treat peri‐implant mucositis and peri‐implantitis

Therapies proposed for the treatment of peri‐implant diseases are primarily based on the evidence available from treating periodontitis. The primary objective is elimination of the biofilm from the implant surface, and nonsurgical therapy is a commonly used treatment. A number of adjunctive therapies have been introduced to overcome accessibility problems or difficulties with decontamination of implant surfaces as a result of specific surface characteristics. It is now accepted that following successful decontamination, clinicians can attempt to regenerate the bone that was lost as a result of infection. The ultimate goal is re‐osseointegration, and a number of regenerative techniques have been introduced. By reviewing the existing evidence, it seems that peri‐implant mucositis is reversible when appropriately treated. Additionally, a combined therapy (mechanical therapy with local antimicrobials as adjuncts) can serve as an alternative to surgical intervention when treating peri‐implantits in cases not suitable for surgery. Surgical therapy is an effective method for treating peri‐implantitis, and various degrees of success of the use of regenerative procedures have been reported, regardless of whether or not radiographic evidence of defect fill has been achieved. Finally, no matter which therapy is employed, a prerequisite for the long‐term stability of treatment results obtained is the ability of the patient to maintain good oral hygiene.