Results of a 20-year oral hygiene and prevention programme on caries and periodontal disease in children attended at a private periodontal practice

To cite this article:
Int J Dent Hygiene 9 , 2011; 155–158
DOI: 10.1111/j.1601‐5037.2010.00455.x
Chambrone LA, Chambrone L. Results of a 20‐year oral hygiene and prevention programme on caries and periodontal disease in children attended at a private periodontal practice. Abstract: Objectives: The objective of this study was to evaluate the long‐term effect of an oral hygiene and prevention programme on caries and periodontal disease in a group of children attended at a private periodontal practice. Methods: A total of 50 systemically healthy children, 25 males and 25 females, 03–13 years old, were invited to join a long‐term plaque control programme. All children had no caries and had no evidence of clinical bone loss. The participants were selected amongst children whose parents (mother, father or both) were treated of gingivitis, aggressive periodontitis or chronic periodontitis in a private periodontal practice. Subjects were separated in groups according to their parents’ periodontal diagnosis, i.e., gingivitis, aggressive periodontitis or chronic periodontitis. The following outcomes were evaluated: a) probing depth, b) plaque (PI) and gingival (GI) indexes. The plaque control programme applied consisted of a regular maintenance regime at 6‐to 12‐month interval with an experienced periodontist. Results: In total 30 subjects fulfilled the 20‐year period of maintenance. The mean recall frequency was 6.4 (± 3.1) months, and the mean PI and GI were 0.4 (± 0.3) and 0.3 (± 0.3) respectively. The average rate of caries lesions was 1.0 (± 1.4). None of the patients exhibited clinical or radiographic evidences of alveolar bone loss, and no tooth was lost by caries. In addition, there were no statistically significant differences between groups (P > 0.05). Conclusions: Adequate oral hygiene measures and periodic professional plaque control led to low levels of dental plaque, gingivitis and caries lesions.     

Salivary nitric oxide levels in inflammatory periodontal disease - a case-control and interventional study

To cite this article: Int J Dent Hygiene 10 , 2012; 67–73
DOI: 10.1111/j.1601‐5037.2011.00508.x
Parwani SR, Chitnis PJ, Parwani RN. Salivary nitric oxide levels in inflammatory periodontal disease – A case‐control and interventional study. Abstract: Background: Biochemical markers of inflammatory periodontal disease present in saliva can partially determine the extent of periodontal disease. Furthermore, collection of salivary constituents is a simple and non‐invasive procedure. Nitric oxide (NO) has been linked to etiopathogenesis of inflammatory periodontal disease and is expressed in saliva. This study was conducted with the objective of estimating salivary NO levels in inflammatory periodontal diseases (gingivitis and periodontitis) and comparing these levels with control subjects. A re‐assessment of these levels was also made after providing appropriate treatment with a view to ascertain its diagnostic and prognostic values. Methods: This was a case–control as well as an interventional study including a total of 90 (30 control, 30 gingivitis and 30 periodontitis) subjects. Saliva samples were collected from each subject, and NO levels were assayed by Griess reaction. Results: NO levels were increased significantly in gingivitis and periodontitis subjects as compared with controls. There was a statistically significant decrease in the NO levels in each study group after the healing period (corresponding to the reduced clinical signs of inflammation). Our study also correlated probing pocket depths with salivary NO levels in periodontitis group where we found a positive correlation between the two. Conclusion: Salivary NO levels can be utilized as a good indicator of the inflammatory status of the periodontium, and evaluating its levels in saliva by Griess reaction on a photoelectric colorimeter is a reliable, accurate and faster method to estimate the level of inflammation in periodontal tissues.     

Deproteinized bovine bone mineral in marginal defects at implants installed immediately into extraction sockets: an experimental study in dogs

Aim: To evaluate the influence of deproteinized bovine bone mineral (DBBM) particles concomitant with the placement of a collagen membrane on alveolar ridge preservation and on osseointegration of implants placed into alveolar sockets immediately after tooth extraction. Material and methods: The pulp tissue of the mesial roots of ₃P₃ was removed in six Labrador dogs and the root canals were filled. Flaps were elevated in the right side of the mandible, and the buccal and lingual alveolar bony plates were exposed. The third premolar was hemi‐sectioned and the distal root was removed. A recipient site was prepared and an implant was placed lingually. After implant installation, defects of about 0.6 mm wide and 3.1 mm depth resulted at the buccal aspects of the implant, both at the test and at the control sites. The same surgical procedures and measurements were performed on the left side of the mandible. However, DBBM particles with a size of 0.25–1 mm were placed into the remaining defect concomitant with the placement of a collagen membrane. Results: All implants were integrated into mature bone. No residual DBBM particles were detected at the test sites after 4 months of healing. Both the test and the control sites showed buccal alveolar bone resorption, 1.8±1.1 and 2.1±1 mm, respectively. The most coronal bone‐to‐implant contact at the buccal aspect was 2±1.1 an 2.8±1.3 mm, at the test and the control sites, respectively. This difference in the distance was statistically significant. Conclusion: The application of DBBM concomitant with a collagen membrane to fill the marginal defects around implants placed into the alveolus immediately after tooth extraction contributed to improved bone regeneration in the defects. However, with regard to buccal bony crest preservation, a limited contribution of DBBM particles was achieved. To cite this article:
Caneva M, Botticelli D, Pantani F, Baffone GM, Rangel IG Jr, Lang NP. Deproteinized bovine bone mineral in marginal defects at implants installed immediately into extraction sockets: an experimental study in dogs.
Clin. Oral Impl. Res. 23 , 2012; 106–112.
doi: 10.1111/j.1600‐0501.2011.02202.x     

The alveolar process of the edentulous maxilla in periodontitis and non-periodontitis subjects

Background: Early implant failures may document that the bone tissue or the wound‐healing process following installation surgery was compromised. Subjects who have lost teeth for periodontal reasons exhibit more earlier implant failures than subjects who had experienced tooth loss for other reasons. Aim: To describe the tissue of the fully healed extraction sites in subjects who had lost teeth as a result of periodontitis or for other reasons. Material and methods: Thirty‐six otherwise healthy, partially dentate subjects with fully healed edentulous portions in the posterior maxilla were included. Nineteen of these subjects had lost teeth because of advanced periodontitis (group P) and 17 for other reasons (group NP). Using a trephine drill, a 4–6 mm long hard tissue specimen was harvested. The biopsies were decalcified, embedded in paraffin, sectioned, stained and examined. Results: The edentulous posterior maxilla was comprised of 47.1 ± 11% lamellar bone, 8.1 ± 7.1% woven bone, 4.3 ± 3.1% osteoid and 16.5 ± 10.4% bone marrow. There were no significant differences in the tissue composition of post‐extraction sites of (i) P and NP subjects and (ii) premolar and molar sites. Conclusion: More than 50% of the edentulous maxilla was comprised of mineralized bone (lamellar and woven bone). The bone trabeculae frequently appeared to have a random orientation. The direction of the trabeculae rather than the lack of mineralized bone tissue may explain the clinical impression that the bone in the posterior maxilla provides limited resistance to mechanical instrumentation. To cite this article: Lindhe J, Cecchinato D, Bressan EA, Toia M, Araújo M, Liljenberg B. The alveolar process of the edentulous maxilla in periodontitis and non‐periodontitis subjects. Clin. Oral Impl. Res. 23 , 2012; 5–11
doi: 10.1111/j.1600‐0501.2011.02205.x     

Magnesium-enriched hydroxyapatite at immediate implants: a histomorphometric study in dogs

Aim: To evaluate the influence of magnesium‐enriched hydroxyapatite (MHA) (SintLife^®) on bone contour preservation and osseointegration at implants placed immediately into extraction sockets. Material and methods: In the mandibular pre‐molar region, implants were installed immediately into extraction sockets of six Labrador dogs. MHA was placed at test sites, while the control sites did not receive augmentation materials. Implants were intended to heal in a submerged mode. After 4 months of healing, the animals were sacrificed, and ground sections were obtained for histomorphometric evaluation. Results: After 4 months of healing, one control implant was not integrated leaving n=5 test and control implants for evaluation. Both at the test and the control sites, bone resorption occurred. While the most coronal bone‐to‐implant contact was similar between test and control sites, the alveolar bony crest outline was maintained to a higher degree at the buccal aspect of the test sites (loss: 0.7 mm) compared with the control sites (loss: 1.2 mm), even though this difference did not reach statistical significance. Conclusions: The use of MHA to fill the defect around implants placed into the alveolus immediately after tooth extraction did not contribute significantly to the maintenance of the contours of the buccal alveolar bone crest. To cite this article:
Caneva M, Botticelli D, Stellini E, Souza SLS, Salata LA, Lang NP. Magnesium‐enriched hydroxyapatite at immediate implants: a histomorphometric study in dogs.
Clin. Oral Impl. Res. 22 , 2011; 512–517
doi: 10.1111/j.1600‐0501.2010.02040.x     

Pilot pathfinder survey of oral hygiene and periodontal conditions in the rural population of The Gambia (West Africa)

To cite this article:
Int J Dent Hygiene 9 , 2011; 53–59
DOI: 10.1111/j.1601‐5037.2009.00435.x
Jordan RA, Lucaciu A, Fotouhi K, Markovic L, Gaengler P, Zimmer S. Pilot pathfinder survey of oral hygiene and periodontal conditions in the rural population of The Gambia (West Africa). Abstract: Objective: To document oral hygiene and periodontal conditions in the rural population of The Gambia. Basic research design: Cross‐sectional study according to the recommendations of the WHO for oral health surveys. Clinical setting: Examination by two calibrated investigators in the health centres of rural communities after a public radio call. Patients were randomly allocated to the investigators. Participants: 162 patients (20–54 years old; 52.5% female, 47.5% male). Interventions: Patients were interviewed for personal information and examined in a full‐mouth recording. Main outcome measures: Oral Hygiene Index (OHI), Gingival Index (GI), Community Periodontal Index (CPI), and the Gingivitis‐Periodontitis‐Missing/Teeth Index (GPM/T). Statistical analysis was performed using the Wilcoxon‐rank‐sum test and Kruskal–Wallis test with statistical significance at P < 0.05. Results: OHI increased by age from 6.9 to 9.2 (P < 0.05) and showed in tendency higher levels in men (P = 0.07), while the GI remained stable at 1.2. Community Periodontal Index codes increased by age (P < 0.05) and showed a fourfold higher prevalence for severe periodontitis in males (P < 0.05). Likewise, an age‐related increase in GPM/T was evident (20.5 versus 25.4), significantly in the number of moderate periodontitis and missing teeth (P < 0.05). In GPM/T, males again demonstrated significantly more teeth affected by periodontitis than women. No statistical associations were found between ethnic groups or for different oral hygiene methods concerning CPI or GPM/T. Conclusions: Prevalence of predominantly mild to moderate periodontal disease indicates treatment needs that should be considered when developing a national oral health care plan in The Gambia (West Africa).     

Periodontal risk assessment model in a sample of regular and irregular compliers under maintenance therapy: a 3-year prospective study

Background: The purpose of this study is to investigate the association of the periodontal risk assessment (PRA) model with the recurrence of periodontitis and tooth loss during periodontal maintenance therapy (PMT). Methods: In a prospective PMT program, 75 regular complier (RC) and 89 erratic complier (EC) patients were selected. A periodontal examination and PRA were performed after active periodontal therapy and after 3 years of PMT. Risk profiles (low, moderate, or high) of participants were evaluated, and the recurrence of periodontitis and tooth loss were analyzed using univariate and multivariate analyses. Results: RCs showed less recurrence of periodontitis and tooth loss than ECs (P <0.05). Rates of periodontitis recurrence in RCs and ECs were 2.7% and 3.4%, respectively, for the moderate‐risk profile and 6.7% and 11.2%, respectively, for the high‐risk profile. During PMT, 49 teeth (0.65 ± 1.4 teeth per participant) were lost in the RC group, and 70 teeth (0.78 ± 2.1 teeth per participant) were lost in the EC group. High‐risk profile participants showed more recurrence of periodontitis and lost significantly more teeth than did participants with moderate‐ or low‐risk profiles in RC and EC groups (P <0.05). Conclusion: The risk profile influenced the recurrence of periodontitis and tooth loss. RCs had less recurrence of periodontitis and less tooth loss. The PRA model can be useful in particularizing the risk of patients and adjusting recall intervals.     

Effect of silver and fluoride ions on enamel demineralization: a quantitative study using micro-computed tomography

Background: This study aimed to investigate the effect of silver and fluoride ions on demineralization of enamel. Methods: The coronal parts of 40 extracted sound premolars were prepared into tooth blocks. An unvarnished occlusal surface window (OW) and a flat buccal/lingual surface window (FW) were created for each tooth by covering all other surfaces with an acid‐resistant varnish. These blocks were randomly allocated into four groups of 10 blocks each and immersed in respective solutions for 5 minutes: Group 1 – 2.36 M silver fluoride; Group 2 – 2.36 M potassium fluoride; Group 3 – 2.36 M silver nitrate; and Group 4 – deionized water. After 7‐day immersion in a buffered demineralization solution at pH 4.4, micro‐CT scans were taken. Results: Mean lesion depth in the FW area for tooth blocks in AgF, KF, AgNO₃ and control groups were 0 μm, 3.3 ± 10.3 μm, 156.3 ± 30.8 μm, and 173.6 ± 48.6 μm, respectively (p < 0.001). The difference in mean lesion depth between the AgNO₃ and control groups was not statistically significant (p > 0.05). Similar OW and FW lesions were observed in tooth blocks in the AgNO₃ and control groups. Conclusions: Topical application of a 2.36 M fluoride solution can inhibit demineralization of enamel while topical application of silver ions has little effect.     

Complication and failure rates of fixed dental prostheses in patients treated for periodontal disease

Objectives: To evaluate the biological and technical complication rates of fixed dental prostheses (FDP) with end abutments or cantilever extensions on teeth (FDP‐tt/cFDP‐tt) on implants (FDP‐ii/cFDP‐ii) and tooth‐implant‐supported (FDP‐ti/cFDP‐ti) in patients treated for chronic periodontitis. Material and methods: From a cohort of 392 patients treated between 1978 and 2002 by graduate students, 199 were re‐examined in 2005. Of these, 84 patients had received ceramo‐metal FDPs (six groups). Results: At the re‐evaluation, the mean age of the patients was 62 years (36.2–83.4). One hundred and seventy‐five FDPs were seated (82 FDP‐tt, 9 FDP‐ii, 20 FDP‐ti, 39 cFDP‐tt, 15 cFDP‐ii, 10 cFDP‐ti). The mean observation time was 11.3 years; 21 FDPs were lost, and 46 technical and 50 biological complications occurred. Chances for the survival of the three groups of FDPs with end abutments were very high (risk for failure 2.8%, 0%, 5.6%). The probability to remain without complications and/or failure was 70.3%, 88.9% and 74.7% in FDPs with end abutments, but 49.8–25% only in FDPs with extensions at 10 years. Conclusions: In patients treated for chronic periodontitis and provided with ceramo‐metal FDPs, high survival rates, especially for FDPs with end abutments, can be expected. The incidence rates of any negative events were increased drastically in the three groups with extension cFDPs (tt, ii, ti). Strategic decisions in the choice of a particular FDP design and the choice of teeth/implants as abutments appear to influence the risks for complications to be expected with fixed reconstruction. If possible, extensions on tooth abutments should be avoided or used only after a cautious clinical evaluation of all options. To cite this article:
Brägger U, Hirt‐Steiner S, Schnell N, Schmidlin K, Salvi GE, Pjetursson B, Matuliene G, Zwahlen M, Lang NP. Complication and failure rates of fixed dental prostheses in patients treated for periodontal disease.
Clin. Oral Impl. Res. 22 , 2011; 70–77.
doi: 10.1111/j.1600‐0501.2010.02095.x     

Effect of socket preservation therapies following tooth extraction in non-molar regions in humans: a systematic review

Objective: To assess, based on the existing literature, the benefit of socket preservation therapies in patients with a tooth extraction in the anterior or premolar region as compared with no additional treatment with respect to bone level. Material and methods: MEDLINE‐PubMed and the Cochrane Central Register of controlled trials (CENTRAL) were searched till June 2010 for appropriate studies, which reported data concerning the dimensional changes in alveolar height and width after tooth extraction with or without additional treatment like bonefillers, collagen, growth factors or membranes. Results: Independent screening of the titles and abstracts of 1918 MEDLINE‐PubMed and 163 Cochrane papers resulted in nine publications that met the eligibility criteria. In natural healing after extraction, a reduction in width ranging between 2.6 and 4.6 mm and in height between 0.4 and 3.9 mm was observed. With respect to socket preservation, the freeze‐dried bone allograft group performed best with a gain in height, however, concurrent with a loss in width of 1.2 mm. Conclusion: Data concerning socket preservation therapies in humans are scarce, which does not allow any firm conclusions. Socket preservation may aid in reducing the bone dimensional changes following tooth extraction. However, they do not prevent bone resorption because, depending on the technique, on the basis of the included papers one may still expect a loss in width and in height. To cite this article:
Ten Heggeler JMAG, Slot DE, Van der Weijden GA. Effect of socket preservation therapies following tooth extraction in non‐molar regions in humans: a systematic review.
Clin. Oral Impl. Res. 22 , 2011; 779–788
doi: 10.1111/j.1600‐0501.2010.02064.x.
     

Flap vs. “flapless” surgical approach at immediate implants: a histomorphometric study in dogs

Aim: To compare the remodeling of the alveolar process at implants installed immediately into extraction sockets by applying a flap or a “flapless” surgical approach in a dog model. Material and methods: Implants were installed immediately into the distal alveoli of the second mandibular premolars of six Labrador dogs. In one side of the mandible, a full‐thickness mucoperiosteal flap was elevated (control site), while contra‐laterally, the mucosa was gently dislocated, but not elevated (test site) to disclose the alveolar crest. After 4 months of healing, the animals were sacrificed, ground sections were obtained and a histomorphometric analysis was performed. Results: After 4 months of healing, all implants were integrated (n=6). Both at the test and at the control sites, bone resorption occurred with similar outcomes. The buccal bony crest resorption was 1.7 and 1.5 mm at the control and the test sites, respectively. Conclusions: “Flapless” implant placement into extraction sockets did not result in the prevention of alveolar bone resorption and did not affect the dimensional changes of the alveolar process following tooth extraction when compared with the usual placement of implants raising mucoperiosteal flaps. To cite this article:
Caneva M, Botticelli D, Salata LA, Souza SLS, Bressan E, Lang NP. Flap vs. “flapless” surgical approach at immediate implants: a histomorphometric study in dogs.
Clin. Oral Impl. Res. 21 , 2010; 1314–1319.
doi: 10.1111/j.1600‐0501.2009.01959.x     

Do periodontopathogens disappear after full‐mouth tooth extraction?

Aim: To monitor the intra‐oral microbiological changes after full‐mouth extraction using quantitative polymerase chain reaction (qPCR). Material and Methods: Nine patients with severe, aggressive periodontitis, for whom a full‐mouth tooth extraction was the only remaining treatment option were recruited. Before and 6 months after extraction, microbial samples were obtained (tongue, saliva and subgingival plaque) and analysed by qPCR. Results: The elimination of subgingival niches, by extraction of all natural teeth, resulted in a 3‐log reduction of Porphyromonas gingivalis and Tannerella forsythia, and more modest reductions of Aggregatibacter actinomycetemcomitans and Prevotella intermedia. However, the detection frequencies of these periodontopathogens in saliva and on the tongue remained unchanged after full‐mouth tooth extraction. Conclusion: In contrast to what has been believed so far, full‐mouth tooth extraction does not result in eradication of all periodontopathogens but only in a significant reduction. The clinical consequences of this observation remain speculative.     

Persistently raised C-reactive protein levels are associated with advanced periodontal disease

Objective: The aim was to investigate whether there was an association between periodontitis or tooth loss in a homogeneous group of 60–70‐year‐old Western European men and either a sustained high or low level of C‐reactive protein (CRP). Material and Methods: Men enrolled in a cohort study of cardiovascular disease in Northern Ireland were screened in 1990–1994 and rescreened in 2001–2004, when a periodontal examination was completed. High‐sensitivity CRP was measured from fasting blood samples. There were 806 men with six or more teeth who had either a high level (>3 mg/l) or a lower level of CRP at both time points. Multivariate analysis was carried out using logistic regression with adjustment for possible confounders. Models were constructed with the CRP level as the outcome variable and various measures of periodontal status (low and high threshold periodontitis) or tooth loss as predictor variables. Confounders included in the analysis were known cardiovascular risk factors of age, smoking, diabetes, BMI and socioeconomic status. Results: There were 67 men who had a high value of CRP (>3 mg/l) and 739 men who had a CRP value 3 mg/l at both time points. The unadjusted odds ratio (OR) for advanced periodontitis to be associated with high CRP was 3.62, p=0.0003. The association was somewhat attenuated but remained significant (OR=2.49, p=0.02) after adjustment for confounders. A high level of tooth loss was also associated with high CRP with an adjusted OR of 2.17, p=0.008. Low threshold periodontitis was not associated with the level of CRP. Conclusion: There was an association between advanced periodontitis and elevated CRP levels as measured at two time points at a 10‐year interval in the 60–70‐year‐old European males investigated. This association was adjusted for various cardiovascular risk factors. There was also an association between high levels of tooth loss and high CRP in the men studied.     

Oral health status among hospitalized patients

To cite this article:
Int J Dent Hygiene 9 , 2011; 21–29
DOI: 10.1111/j.1601‐5037.2009.00423.x
Carrilho Neto A, De Paula Ramos S, Sant’ana ACP, Passanezi E. Oral health status among hospitalized patients. Abstract: Aim: To investigate into oral health status and its association with health status in hospitalized patients. Methods: A total of 82 patients were examined and 49 (59.7%) patients were men. The patients answered a survey and oral examinations to detect the number of teeth, oral hygiene index, prostheses hygiene, oral lesions, caries, dental plaque index (DPI), gingival inflammation index (GI), gingival bleeding index, periodontitis and periodontal index. Results: Oral hygiene was associated with age, but it was not related to physical disability. Difficulty eating was mainly associated with age and tooth loss. All full and partially dentate patients presented dental plaque, 38 (69%) poor oral hygiene, 58 (98.1%) gingival inflammation, 41 (74.5%) periodontal disease and 33 (60%) caries. Oral lesions were detected in 30 (36.5%) and candidiasis (n = 16, 19.6%) was the most frequent mucous lesion. Caries were associated with smoking and poor oral hygiene. Hospital length of stay and age were associated with increased DPI and GI. Conclusions: The majority of hospitalized patients did not present satisfactory oral hygiene. Caries and periodontal diseases are associated with health behaviours. Increased time length at hospital could increase gingival inflammation and dental plaque accumulation.     

Prospective study in periodontal maintenance therapy: comparative analysis between academic and private practices

Background: This prospective study aims to evaluate and compare the periodontal status, periodontitis progression, tooth loss, and influence of predictable risk variables of two periodontal maintenance therapy programs over a 12‐month period. Methods: A total of 288 individuals diagnosed with chronic moderate‐to‐advanced periodontitis, who had finished active periodontal treatment, were evaluated in a public academic environment (AG) (n = 138), as well as in a private clinic (PG) (n = 150). A full‐mouth periodontal examination was performed at baseline and at quadrimestral recalls, evaluating plaque index, probing depth, clinical attachment level, furcation involvement, bleeding on probing (BOP), and suppuration. Individuals’ social, demographic, and biologic data, as well as compliance with recalls, were recorded. The effect of variables of interest and confounders were tested by univariate and multivariate analysis. Results: The PG demonstrated lower rates of periodontitis progression and tooth loss than did the AG. After adjusting for confounders, the risk variables of BOP (P = 0.047), smoking (P = 0.003), and diabetes (P = 0.028) for the PG and smoking (P = 0.047) for the AG showed a negative influence on periodontal status. Conclusions: In both groups, the periodontal maintenance therapy minimized the negative effect of the risk variables. However, PG showed significantly less progression of periodontitis and tooth loss compared to AG.     

Tooth-related risk factors for tooth loss in community-dwelling elderly people

Hirotomi T, Yoshihara A, Ogawa H, Miyazaki H. Tooth‐related risk factors for tooth loss in community‐dwelling elderly people. Community Dent Oral Epidemiol 2012; 40: 154–163. © 2011 John Wiley & Sons A/S Abstract – Objective: To appropriately explore risk factors for tooth loss operating at the tooth‐level, subject‐related factors and a hierarchical data structure have to be considered. The purpose of this study was to evaluate tooth‐related and subject‐related risk factors affecting tooth loss. Methods: A 10‐year longitudinal survey was carried out on 286 elderly subjects. At baseline, the prosthodontic status and abutment function of the 5574 teeth were recorded. Tooth loss was defined as the main outcome variable, and a multilevel logistic regression model considering subject and tooth levels was applied. Results: Tooth loss was found in 75% of subjects and most frequently in molars. A multivariable, multilevel logistic regression revealed that the following tooth‐related variables were significantly related to tooth loss over 10 years: maxillary teeth, multirooted teeth, single crowns, abutment teeth for a fixed/removable partial denture (FPD/RPD), and periodontally involved teeth. Among them, single crowns, abutment teeth for an FPD, and teeth with severe periodontal disease at baseline had the highest odds of 5.1, 6.0, and 7.1, respectively. Conclusions: The findings of this study suggest that tooth loss is the result of complex interactions of tooth‐related factors. Several tooth‐related variables including multirooted teeth, abutments, and single crowns were found to be possible risk factors for tooth loss. Thus, these findings confirm and underline the potential benefit of minimizing prosthetic treatment of molars.     

Relationship between the prognosis of periodontitis and occlusal force during the maintenance phase – a cohort study

Takeuchi N, Ekuni D, Yamamoto T, Morita M. Relationship between the prognosis of periodontitis and occlusal force during the maintenance phase – a cohort study. J Periodont Res 2010; 45: 612–617. © 2010 John Wiley & Sons A/S Background and Objective: Few studies have longitudinally investigated the relationship between periodontal disease progression and occlusal factors in individual subjects during the maintenance phase of periodontal therapy. The aim of this cohort study was to investigate the relationship between biting ability and the progression of periodontal disease in the maintenance phase. Material and Methods: A total of 194 patients were monitored for 3 years during the maintenance phase of periodontal therapy. The subjects with disease progression (Progress group) were defined based on the presence of ≥ 2 teeth demonstrating a longitudinal loss of proximal attachment of ≥ 3 mm or tooth‐loss experience as a result of periodontal disease during the study period. The subjects with high occlusal force were diagnosed as men who showed an occlusal force of more than 500 N and women who showed an occlusal force of more than 370 N. The association between biting ability and the progression of periodontitis was investigated using logistic regression analysis. Results: There were 83 subjects in the Progress group and 111 subjects in the Non‐progress group. A backward, stepwise logistic regression model showed that the progression of periodontal disease was significantly associated with the presence of one or more teeth with a high clinical attachment level (CAL) of ≥ 7 mm (odds ratio: 2.397; 95% confidence interval: 1.306–4.399) ( p = 0.005) and low occlusal force (odds ratio: 2.352; 95% confidence interval: 1.273–4.346) ( p = 0.006). Conclusion: The presence of one or more teeth with a high CAL of ≥ 7 mm and low occlusal force might be possible risk factors for periodontal progression in the maintenance phase of periodontal therapy.     

Do elderly edentulous patients with a history of periodontitis harbor periodontal pathogens?

Objectives: The presence of periodontal pathogens in the oral cavity may impact implant survival. Therefore, this study aimed to determine the prevalence of Campylobacter rectus, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Tannerella forsythia, Treponema denticola, Eikenella corrodens and Parvimonas micra in a specific elderly population with a history of periodontitis who have never worn dentures. Material and methods: Thirty dentate subjects (mean age 61.7±7.05 years) and 30 edentulous subjects (mean age 65.8±8.05 years) were included in this cross‐sectional study. Microbiological samples of cheek mucosa and the dorsum of the tongue were taken from all subjects. In addition, sulcus samples were taken from the dentate group. All samples were analysed using a bacterial DNA‐specific polymerase chain reaction. Results: All the pathogens studied were detected in dentate and edentulous subjects. When cheek and tongue samples were combined, C. rectus, A. actinomycetemcomitans and E. corrodens presented with a similar prevalence in both groups, whereas the other species were more prevalent specifically in the dentate group (P<0.05). In dentate subjects, P. intermedia and T. denticola were present in higher frequencies in the cheek mucosa (26.67% and 66.67%, respectively), whereas P. gingivalis and T. forsythia were more prevalent in the tongue samples (26.67% and 56.67%, respectively). Conclusions: Periodontal pathogens may persist in the oral cavity of edentulous subjects who have had periodontal disease, even 1 year after the extraction of all teeth and in the absence of other hard surfaces in the mouth. To cite this article:
Fernandes CB, Aquino DR, Franco GCN, Cortelli SC, Costa FO, Cortelli JR. Do elderly edentulous patients with a history of periodontitis harbor periodontal pathogens?
Clin. Oral Impl. Res. 21 , 2010; 618–623.
doi: 10.1111/j.1600‐0501.2009.01892.x     

Reactions of periodontal ligament epithelial cell clusters and OX6-immunopositive cells to experimental tooth movement and periodontitis

Tadokoro O, Kawahara I, Vandevska‐Radunovic V. Reactions of periodontal ligament epithelial cell clusters and OX6‐immunopositive cells to experimental tooth movement and periodontitis. J Periodont Res 2011; 46: 584–591.©2011 John Wiley & Sons A/S Background and Objective: The aim of this study was to investigate reactions of periodontal ligament epithelial cell clusters and major histocompatibility complex class II (OX6)‐immunopositive cells to simultaneously induced tooth movement and periodontitis employing Waldo’s method. Material and Methods: Elastic gums were inserted between the right upper first and second molars of rats. Animals were killed by intracardiac perfusion on days 1, 3, 7 and 14 after the experimental procedures, and maxillary molars were decalcified and processed for OCT compound. Cytokeratin and OX6 antibodies to detect epithelial and immunocompetent cells were used for double‐fluorescence immunohistochemistry. Immunostained sections of rat upper molar regions were examined with a fluorescence microscope. Results: Large periodontal ligament epithelial cell clusters appeared and became contiguous with each other, and OX6‐immunopositive cells surrounded the clusters over time in the periodontal ligament near the gum insertion site. In the periodontal ligament distant from the gum insertion site, epithelial cell clusters and OX6‐immunopositive cells were scattered. After 14 d, thickened epithelium and elongated rete pegs were found close to large epithelial cell clusters in the periodontal ligament near the gum insertion site. Conclusion: These findings suggest proliferation and/or aggregation of periodontal ligament epithelial cells, and interaction between OX6‐immunopositive cells and the periodontal ligament epithelial cells, in response to tooth movement and periodontal inflammation. This method may be a useful experimental model to elucidate the relationship between rete pegs and periodontal ligament epithelial cell clusters in inflammatory conditions.     

Bio-Oss collagen in the buccal gap at immediate implants: a 6-month study in the dog

Background: Following tooth extraction and immediate implant installation, the edentulous site of the alveolar process undergoes substantial bone modeling and the ridge dimensions are reduced. Objective: The objective of the present experiment was to determine whether the process of bone modeling following tooth extraction and immediate implant placement was influenced by the placement of a xenogenic graft in the void that occurred between the implant and the walls of the fresh extraction socket. Material and methods: Five beagle dogs about 1 year old were used. The 4th premolar in both quadrants of the mandible (₄P₄) were selected and used as experimental sites. The premolars were hemi‐sected and the distal roots removed and, subsequently, implants were inserted in the distal sockets. In one side of the jaw, the marginal buccal‐approximal void that consistently occurred between the implant and the socket walls was grafted with Bio‐Oss^® Collagen while no grafting was performed in the contra‐lateral sites. After 6 months of healing, biopsies from each experimental site were obtained and prepared for histological analyses. Results: The outline of the marginal hard tissue of the control sites was markedly different from that of the grafted sites. Thus, while the buccal bone crest in the grafted sites was comparatively thick and located at or close to the SLA border, the corresponding crest at the control sites was thinner and located a varying distance below SLA border. Conclusions: It was demonstrated that the placement of Bio‐Oss^® Collagen in the void between the implant and the buccal‐approximal bone walls of fresh extraction sockets modified the process of hard tissue healing, provided additional amounts of hard tissue at the entrance of the previous socket and improved the level of marginal bone‐to‐implant contact. To cite this article:
Araújo MG, Linder E, Lindhe J. Bio‐Oss^® Collagen in the buccal gap at immediate implants: a 6‐month study in the dog.
Clin. Oral Impl. Res. 22 , 2011; 1–8.
doi: 10.1111/j.1600‐0501.2010.01920.x