Differential diagnosis in clinical trials of therapy for periodontitis

Evaluation of IL6, IL10 and VDR alleles distribution in an Italian large sample of subjects affected by chronic periodontal disease

In recent decades, the role played by the immune response to bacteria in the pathogenesis of chronic periodontal disease (PD) has long been studied. Although from the clinical point of view, adequate oral hygiene is essential to ensure a satisfactory response of the host to infections, modulation of the reaction of immune system could be influenced by genetic factors. The aim of the present study was to investigate the distribution of alleles of polymorphisms relevant for chronic periodontitis in a sample of adult subjects affected by chronic PD. The present study was conducted with sample collected in Italian private practice offices from January 2013 to December 2017. The sample included 744 adult patients diagnosed with chronic periodontitis. The inclusion criteria were as follows: age > 18 years, diagnosis of chronic PD. The diagnosis of chronic periodontitis was based on the criteria established by the American Academy of Periodontology. No significant difference in allele distribution among patients from different Italian regions was found. Results, supporting absence of population heterogeneity for the investigated polymorphisms in Italy, suggest similar effect in periodontitis etiology.

A combination of clinical and microbiological management of generalized aggressive periodontitis in primary teeth. A case report

BACKGROUND

Generalized aggressive periodontitis (GAP) in primary teeth is a rare periodontal disease that occurs during or soon after eruption of the primary teeth. An association with systemic diseases is a possibility.

CASE REPORT

A 4-year-old Brazilian girl presented with GAP involving the entire primary dentition. The patient and her parents and sister were subjected to microbiological testing to identify the microorganisms involved in the disease. The patient underwent tooth extraction to eradicate the disease and received a prosthesis for the restoration of masticatory function. After the permanent teeth erupted, fixed orthodontic appliances were place to restore dental arch form and occlusion.

CONCLUSIONS

The results show the importance of an early diagnosis of GAP and of a multidisciplinary approach involving laboratory and clinical management to treat the disease and to restore masticatory function, providing a better quality of life for patients.

Effect of a Controlled-Release Chlorhexidine Chip on Clinical and Microbiological Parameters and Prostaglandin E2Levels in Gingival Crevicular Fluid

BACKGROUND

The aim of the present study was to determine the effect of a chlorhexidine chip on crevicular prostaglandin E2 (PGE2) levels and on the clinical and microbiological parameters of periodontitis when used as adjunctive therapy to scaling and root planing (SRP) in patients with chronic periodontitis.

METHODS

This randomized single-blind study was carried out in parallel design. The test group received SRP plus chlorhexidine chip, whereas the control group received SRP alone. Thirty-four subjects, aged 20 to 55 years, with chronic periodontitis were recruited. Clinical indices, microbiological samples, and gingival crevicular fluid (GCF) samples were evaluated at baseline and after 1, 3, and 6 months. Microbiological samples were evaluated under a light microscope. GCF PGE2 levels were determined using radioimmunoassay.

RESULTS

Significant improvements could be found for all clinical variables in both groups over the study period. The mean changes in probing depth obtained by SRP plus chlorhexidine chip were greater than those obtained by the SRP alone group at 3 and 6 months. In the test group, there was also significant gain in clinical attachment level at 6 months. When data were combined from all groups, significant reductions in GCF PGE2 levels and number of microorganisms were noted at all time points. However, in the test group, reduction was greater at 6 months for crevicular PGE2 level and at 3 and 6 months for proportions of spirochetes.

CONCLUSION

Based on the findings of this study, the chlorhexidine chip reduced GCF PGE2 levels and had positive effects on clinical parameters and subgingival flora when used as adjunctive therapy to SRP in patients with chronic periodontitis.

Linkage disequilibrium analysis of case-control data: an application to generalized aggressive periodontitis

Several studies have shown a role for the involvement of interleukin (IL)-1 gene cluster polymorphisms in the risk of periodontal diseases. In the present study, we tested polymorphisms, derived from genes of the IL-1 cluster, for association with generalized aggressive periodontitis (GAP) through both allelic association and by constructing a linkage disequilibrium (LD) map of the 2q13-14 disease candidate region. The IL-1RN (VNTR) genotype distribution observed was significantly different in GAP and control subjects (P=0.019). We also observed some evidence for an association between GAP and the IL-1B(+3953) polymorphism (P=0.039). The pattern of association in the region, represented as an LD map, identifies a recombination hot area between the IL-1B(+3953) and IL-1B(-511) polymorphisms. Multilocus modelling of association with disease gives a location for the peak association at the IL-1B(+3953) marker, although support for the peak is not significant. Haplotype analysis identifies a IL-1B(+3953)-IL-1B(-511) haplotype as having the lowest P-value in the region. Recognition of the presence of a recombination hot area between the IL-1B(+3953) and IL-1B(-511) polymorphisms will have an important bearing on future efforts to develop higher resolution SNP analysis in this region for both this and other diseases for which this cluster is implicated.

Association of interleukin-1 receptor antagonist gene polymorphisms with early onset periodontitis in Japanese

BACKGROUND/AIMS

Early onset periodontitis (EOP), newly 'aggressive periodontitis', is considered to have genetic basis, which have not been clearly defined. The interleukin-1 (IL-1) gene cluster polymorphism as one of genetic factors may influence the expression of several chronic inflammatory diseases. The aim of this study is to investigate the frequency of single nucleotide polymorphisms (SNPs) in the genes encoding IL-1alpha, IL-1beta and a variable number of tandem repeat (VNTR) polymorphisms in the IL-1 receptor antagonist gene (IL-1RN) in 47 generalized EOP (G-EOP) patients and 97 periodontally healthy controls.

MATERIAL AND METHODS

All subjects were of Japanese descent and systemically healthy. They were identified according to established clinical criteria. SNPs in the IL-1alpha (+ 4845) and IL-1beta (- 511, + 3954) genes were analyzed by amplifying the polymorphic region using polymerase chain reaction (PCR), followed by restriction-enzyme digestion and agarose gel electrophoresis. IL-1RN (VNTR) polymorphisms were then detected by PCR amplification and fragment size analysis.

RESULTS

There was no significant difference in the IL-alpha (+ 4845) and IL-1beta (- 511, + 3954) genotypes and allele frequencies between G-EOP patients and healthy controls. However, the frequency of IL-1RN (VNTR) polymorphic alleles was found to be significantly increased in G-EOP patients (chi2 test, P = 0.007; odds ratio = 3.40). Additionally, the carriage rate of IL-1RN (VNTR) polymorphisms was significantly higher in G-EOP patients than in healthy controls (chi2 test, P = 0.005; odds ratio = 3.81).

CONCLUSION

These findings suggest that IL-1RN (VNTR) polymorphisms are associated with G-EOP in Japanese.

5 polymorphisms in the transforming growth factor-beta 1 gene (TGF-beta 1) in adult periodontitis

OBJECTIVES

Transforming growth factor-beta (TGF-beta) represents a family of polypeptide growth factors, involved in inflammation and regulation of immune responses. The purpose of this study was to determine whether polymorphisms in the TGF-beta 1 gene may confer susceptibility to adult periodontitis.

MATERIAL AND METHODS

We studied 90 patients with adult periodontitis together with 108 unrelated subjects. 3 polymorphisms located in the 5'region at positions -988 (C/A), -800 (G/A) and -509 (C/T) and 2 polymorphisms located at codons 10 (L10P) and 25 (R25P) of exon 1 were investigated by PCR methods.

RESULTS

There was no statistically-significant difference in genotype or allele frequency distributions between patients and reference group for the -800G/A, -509C/T, L10P and R25P polymorphisms (p>0.05 in all cases). The -988 A polymorphism was present neither in our patients nor in unrelated subjects. Upon stratification for smoking status no significant differences were found in the TGF-beta 1 genotype or allele frequencies either between adult periodontitis smokers compared to control smokers, or between periodontitis non-smokers and control non-smokers.

CONCLUSION

These data indicate that the mentioned polymorphisms of the TGF-beta 1 gene do not influence susceptibility to adult periodontitis. There was no association between any polymorphisms in the TGF-beta 1 gene, severity of periodontitis and the smoking status in our study.

Analysis of single nucleotide polymorphisms in the 5'-flanking region of tumor necrosis factor-alpha gene in Japanese patients with early-onset periodontitis

BACKGROUND

Early-onset periodontitis (EOP) is considered to have a genetic basis, which has not been clearly defined. The tumor necrosis factor-alpha (TNF-alpha) gene polymorphism as one of the genetic factors may influence the expression of several chronic inflammatory diseases. The aim of the present study was to evaluate whether the polymorphisms in the 5'-flanking region of the TNF-alpha gene are associated with Japanese EOP patients.

METHODS

Forty-six Japanese, generalized EOP (G-EOP) patients and 104 Japanese healthy subjects were identified according to established clinical criteria. Twenty healthy subjects were analyzed by nucleotide sequence to screen polymorphisms of the 5'-flanking region of the TNF-alpha gene. Then, all subjects were analyzed by polymerase chain reaction and sequence-specific oligonucleotide probe (SSOP) methods.

RESULTS

We determined 5 single nucleotide polymorphisms at positions -1031 (T/C), -863 (C/A), -857 (C/T), -308 (G/A), and -238 (G/A) in the 5'-flanking region of the TNF-alpha gene. There were no significant differences in the genotype and allele frequency when we compared G-EOP patients to healthy subjects. Because the frequency of polymorphic alleles at positions -308 and -238 was very low in this study population, we demonstrated the existence of 4 detected haplotypes and 6 detected genotypes concerning 3 single nucleotide polymorphisms (-1031, -863, and -857). The frequency of the H1/H3 (TCC/TCT)-detected genotype tended to decrease in G-EOP patients compared to healthy subjects, but was not statistically significant.

CONCLUSION

These findings suggest there is no significant association between polymorphisms in the 5'-flanking region of the TNF-alpha gene and susceptibility to G-EOP in Japanese patients.

Interactions of lymphotoxin alpha (TNF-beta), angiotensin-converting enzyme (ACE), and endothelin-1 (ET-1) gene polymorphisms in adult periodontitis

BACKGROUND

Adult periodontitis is a complex multifactorial disease whose etiology is not well defined. To investigate whether the genes encoded within the HLA class III region may confer susceptibility to periodontitis, polymorphisms in the ET-1 and TNF-beta genes were analyzed together with the I/D polymorphism of the ACE gene.

METHODS

We determined allele and genotype frequencies of the NcoI bi-allelic polymorphism of the TNF-beta gene, the I/D (insertion/deletion) polymorphism of the ACE gene, and the TaqI polymorphism of the ET-1 gene in 63 Caucasian patients with adult periodontitis and 95 orally healthy controls.

RESULTS

We found a significant difference in a 3 locus combination of genotypes between patients and controls (P<0.05). In the next analyses, no significant differences were found in allele frequencies of single genes, but we did find a significant difference in the genotype distribution between cases and controls for TNF-beta (P<0.03). Differences were also observed for 2 locus combinations of ACE and TNF-beta genotypes (P<0.03), and the ET-1 and TNF-beta (P<0.05) genes. Evidence of deviation from Hardy-Weinberg equilibrium was observed in the periodontitis group for TNF-beta, with an absence of the B1B1 homozygotes in patients.

CONCLUSIONS

This study is of an exploratory nature. Considering the number of significant results, however, at least a part of the observed associations may obviously be real and our findings suggest that interactions of the TNF-beta, ET-1, and ACE genes may be involved in susceptibility to adult periodontitis.

Analysis of genetic polymorphisms at the interleukin-10 and tumour necrosis factor loci in early-onset periodontitis

Early onset periodontitis (EOP) is considered to have a substantial genetic basis, although the gene or genes involved have not been elucidated. The aim of the present study was to investigate possible links between generalized EOP (GEOP) and genes regulating expression of the cytokines tumour necrosis factor (TNF) and interleukin-10 (IL-10). Microsatellite marker DNA sequences corresponding to phenotypic variations in cytokine response were analysed. Genotypic variations in cytokine response have been shown in vitro for TNF and IL-10, and specific alleles are implicated in diseases such as systemic lupus erythmatosus (SLE) and rheumatoid arthritis (RA). Two microsatellites at the IL-10 locus, IL10.R and IL10.G, and 1 microsatellite at the TNF locus, TNFa, were typed for 77 GEOP patients in the West of Scotland. Due to the highly polymorphic nature of the microsatellite loci, a statistical comparison with ethnically matched healthy controls (TNFa, n = 91, IL10.R, n = 94, IL10.G, n = 102) was conducted using a Monte Carlo simulation for each marker. No significant differences were observed for any of the 3 markers, although there were possible indications of trends similar to those observed in SLE for the IL10.G marker. In conclusion, no links were found between GEOP and microsatellites at TNFa, IL10.R or IL10.G loci.

Concepts of quality and the provision of periodontal care: a survey

This is a survey of various concepts of quality of care in the health care field and their application to periodontics. Definitions of quality care, measuring and improving quality, third party payment and quality of care, and the role of periodontists in managing quality are presented. The definitions of quality care include the following dimensions: access, appropriateness, technical quality, and the art of care. Examples of each of these dimensions are presented, and their implications for quality assessment are discussed. Emphasis is placed on appropriateness of care and the strengths and weaknesses of mechanisms for deriving evidence-based decision making. The use of randomized clinical trials (RCT), employing expert opinion such as consensus panels, and meta-analysis are discussed as they apply to appropriateness of periodontal treatment. Work in the area of technical quality of care (i.e., the third dimension of quality care) has resulted in the development of quality assurance guidelines. Examples of guidelines and practice parameters such as those developed by the U.S. Food and Drug Administration and by various dental specialties are presented. The fourth dimension of quality deals with the art of care. It focuses on the patient's participation in the process of care and the input of the provider in this interaction. The description of outcomes of care includes the concept of measuring clinical outcomes of treatment as well as efforts to measure the health and well-being of a patient. It deals with quality of life measures. Patient satisfaction is another outcome that is presented. Examples of these aspects of quality measurement are discussed. These concepts and measures are presented within the context of a quality assurance program. The steps used to assess and assure quality are outlined. Examples of provider and patient profiles are presented, along with a discussion on how they are used in a quality assurance system. Lastly, the role of the periodontist in quality of care is presented, emphasizing the efforts that have already been made as well as the leadership role that the periodontist has in influencing the profession of dentistry. The advent of managed care and its implications for the quality of periodontal treatment and patient management are discussed using situations obtained from dental plans.

Specific issues in clinical trials on the use of barrier membranes in periodontal regeneration

There are presently a number of different barriers available for use clinically in guided tissue regeneration (GTR) procedures. A number of trials using these techniques and comparing different types of barrier membranes are being published in the scientific literature. This review discusses issues related to clinical trials on the use of barrier membranes in periodontal regeneration. Outcome measures, both clinical and histological, are discussed in relation to results following GTR procedures. The difference between regeneration and repair is reviewed as well as methods of clinical and histologic assessment of both these outcomes. Data regarding the impact of patient variables and tooth or defect variables on outcomes are presented and suggestions for study designs are made based on these variables. Aspects of assessing for an appropriate sample size in superiority and equivalency trials using GTR techniques are presented as well as interpretation of results following these trials and their clinical significance.

Comparison between 2 surgical techniques for the treatment of early-onset periodontitis

The objective of this study was to compare guided tissue regeneration (GTR) and osseous surgery (OS) in treatment of early-onset periodontitis. Six patients participated in this research, presenting 15 paired defects randomly assigned to 1 of the surgical groups. Pre-operative clinical parameters (probing depth and attachment loss) between the two groups were not significantly different. Results 1 year following surgery showed probing depth reduction (2.60 +/- 1.30 mm) and clinical attachment gain (2.20 +/- 1.42 mm) were significantly greater in the GTR group than in the osseous surgery group (P < 0.05). The gingival recession was -0.53 +/- 0.52 mm and -0.40 +/- 0.74 mm for the osseous and the guided tissue regeneration group, respectively (no significant difference, P > 0.05). Radiographic analysis by two techniques illustrated that the interproximal alveolar bone changes at the margin of the defects in the OS group were slightly decreased (-0.20 +/- 1.15; 0.26 +/- 0.74 mm) and those in the GTR group were slightly increased (0.16 +/- 0.96; 0.26 +/- 0.68 mm), but showed no significant difference (P > 0.05). The base of the GTR-treated defects showed significant increase in bone fill (1.67 +/- 0.68; 1.97 +/- 0.74 mm; P < 0.05). At a follow-up reexamination 1 year following surgery, oral hygiene and gingival conditions in both groups were at satisfactory levels and gingiva was clinically healthy throughout the entire study period, except the first 4 to 6 weeks following surgery.