Regenerative benefits of using growth factors in treatment of periodontal defects: A systematic review and meta-analysis with Trial Sequential Analysis on preclinical studies.

The ultimate goal in periodontal treatments is to achieve a functional and anatomical regeneration of the lost tissues. Numerous studies have in some way illustrated the beneficial effects of biologic modifiers in this process, yet they are subject to a rather large degree of diversity in their results. Thanks to the promising outcomes of bioengineering techniques in the field of periodontal regeneration, this systematic review aims to evaluate the effect of various biologic modifiers used in periodontal defects of animal models. Electronic databases (Medline, Scopus, Embase, Web of Science, and Google Scholar) were searched (March 2010-December 2020) for every study that used biomolecules for regeneration of periodontal osseous defects in animal models. Regenerated bone height or area, new cementum, new connective tissues, new regenerated periodontal ligament and the dimensions of epithelial attachment (either in mm/mm2 or percentage) were the investigated outcomes. The risk of bias of the included studies was assessed using the SYRCLE tool. In closing, there was a meta-analysis carried out on the outcomes of interest. Trial Sequential Analysis was also carried out to figure out the power of meta-analytic outcomes. From 1995 studies which were found in the initial search, 34 studies were included in this review, and 20 of them were selected for the meta-analysis. The eligible studies were categorized according to the morphology of the experimental periodontal defects as one-, two-, and three-wall intrabony defects; furcation defects, and recession-type defects. The most studied biomolecules were rhFGF-2, rhGDF-5, platelet-derived growth factor, bone morphogenetic protein-2, and enamel matrix derivative (EMD). Based on the meta-analysis findings, combined application of biomolecules with regenerative treatments could improve new bone and cementum formation near 1 mm when compared to the control groups in one, two and three-wall intrabony defect models (p < 0.001). In furcation grade II defect, the addition of biomolecules was observed to enhance bone area gain and cementum height regeneration up to almost 2 mm (p < 0.001). Trial Sequential Analysis results confirmed the significant effect in the aforementioned meta-analyses. In cases of the buccal recession model, the application of rhFGF-2 and rhGDF-5 decreased the dimension of epithelial attachments besides regenerative advantages on bone and cementum formation, but EMD deposition exerted no inhibitory effect on epithelial down-growth. Application of biologic modifiers especially FGF-2 and GDF-5, could positively improve the regeneration of periodontal tissues, particularly cementum and bone in animal models. Trial Sequential Analysis confirmed the results but the power of the evidences was high just in some subgroup meta-analyses, like bone and cementum regeneration in furcation grade II model and cementum regeneration in one-wall intrabony defects. The outcomes of this study can potentially endow clinicians with guidelines for the appropriate application of growth factors in periodontal regenerative therapies.

Effect of perforation size and furcal lesion on stress distribution in mandibular molars: a finite element analysis.

AIM: To compare the effect of furcal perforations of various sizes on the biomechanical response of mandibular first molars with or without periodontal bone loss at the furcal region via three-dimensional (3D) finite element analysis (FEA). METHODOLOGY: The 3D geometric basic model was reconstructed from the micro-computed tomographic images of an extracted mandibular first molar. Five different models were constructed from this molar in group 1 as follows: intact molar model, root filled (RCF) model and three models with furcal perforations (1, 2 and 3 mm in diameter) repaired with a calcium silicate-based cement (CSC). In group 2, a lesion simulating bone resorption at the furcal region was modelled on the models in group 1. A force of 200 N was applied to simulate normal occlusal loads. Static linear FEA was performed using the Abaqus software (Abaqus 6.14; ABAQUS Inc., Providence, RI, USA). The maximum principal stresses (Pmax ) and maximum displacement magnitude were evaluated. RESULTS: The range of Pmax values of the models in group 1, from high to low, was as follows: RCF + 3 mm perforation > RCF + 2 mm perforation > RCF + 1 mm perforation > RCF > intact model, and the range of Pmax values of the models in group 2 was as follows: RCF + 3 mm perforation + furcal lesion > RCF + 2 mm perforation + furcal lesion > RCF + 1 mm perforation + furcal lesion > RCF + furcal lesion > intact model + furcal lesion. All of the models in group 2 exhibited lower Pmax values and higher maximum displacement magnitude than their counterparts without lesions in group 1. CONCLUSIONS: The size of the furcal perforation affected the accumulation and distribution of stress within the models. Mandibular molar teeth with large furcal perforations treated with a calcium silicate-based cement may be associated with an increased risk of fracture whether or not accompanied by bone resorption.

The effect of brain-derived neurotrophic factor on periodontal furcation defects.

This study aimed to observe the regenerative effect of brain-derived neurotrophic factor (BDNF) in a non-human primate furcation defect model. Class II furcation defects were created in the first and second molars of 8 non-human primates to simulate a clinical situation. The defect was filled with either, Group A: BDNF (500 µg/ml) in high-molecular weight-hyaluronic acid (HMW-HA), Group B: BDNF (50 µg/ml) in HMW-HA, Group C: HMW-HA acid only, Group D: empty defect, or Group E: BDNF (500 µg/ml) in saline. The healing status for all groups was observed at different time-points with micro computed tomography. The animals were euthanized after 11 weeks, and the tooth-bone specimens were subjected to histologic processing. The results showed that all groups seemed to successfully regenerate the alveolar buccal bone, however, only Group A regenerated the entire periodontal tissue, i.e., alveolar bone, cementum and periodontal ligament. It is suggested that the use of BDNF in combination with a scaffold such as the hyaluronic acid in periodontal furcation defects may be an effective treatment option.

Progression of periodontitis in a sample of regular and irregular compliers under maintenance therapy: a 3-year follow-up study.

BACKGROUND: To our knowledge, prospective studies (matched for sex, smoking, and diabetes) that investigated the influence of compliance in the progression of periodontitis and tooth loss in periodontal maintenance therapy (PMT) programs were not previously reported. METHODS: A total of 58 regular complier (RC) and 58 erratic complier (EC) individuals were recruited from a prospective cohort with 238 patients under PMT and matched by sex, diabetes, and smoking habits. A full-mouth periodontal examination that included bleeding on probing (BOP), probing depths (PDs), clinical attachment levels, and number of teeth were determined at all PMT visits during a 3-year interval. The influence of variables of interest was tested through multivariate logistic regression. RESULTS: The progression of periodontitis and tooth loss was significantly lower among RC compared to EC patients. A higher progression of periodontitis was observed among EC patients who smoked. The final logistic model for the progression of periodontitis in the RC group included smoking (odds ratio [OR]: 4.2) and >30% of sites with BOP (OR: 2.8), and the final logistic model for the progression of periodontitis in the EC group included smoking (OR: 7.3), >30% of sites with BOP (OR: 3.2), PDs of 4 to 6 mm in 10% of sites (OR: 3.5), diabetes (OR: 1.9), and number of lost teeth (OR: 3.1). CONCLUSIONS: RC patients presented a lower progression of periodontitis and tooth loss compared to EC patients. This result highlighted the influence of the pattern of compliance in maintaining a good periodontal status. Moreover, important risk variables such as smoking and diabetes influenced the periodontal status and should be considered when determining the risk profile and interval time for PMT visits.

Detection of the furcation involvement of a multi-rooted molar using natural frequency analysis: a numerical approach.

The aim of this study was to evaluate the potential for using the natural frequency (NF) as a parameter to detect vertical bone loss at the furcation of human molars as well as to assess the role that the surrounding bone plays in maintaining molar stability. A three-dimensional finite element model of the human maxillary molar was built. The NF values of the molar modal were calculated with one-sided, two-sided, and three-sided vertical bone loss. It was found that the change in the NF was less than 25 per cent in molars with a one-sided defect when the bone level varied by 10 mm from the cementoenamel junction. However, when a three-sided bony defect was simulated, the change in the NF ranged from 40 to 60 per cent. In addition, it was found that bone loss that had reached the furcation entrance (4 mm) resulted in a sharp change in the NF value. Furthermore, it was found that bone loss involving the mesial and distal surfaces resulted in a larger decrease in the NF value compared with bone loss involving the buccal and palatal surfaces. These results demonstrated that the bone surrounding the mesial and distal sides plays a more important role in maintaining molar stability than does the bone surrounding the buccal and palatal sides.

Research on promoting periodontal regeneration with human basic fibroblast growth factor-modified bone marrow mesenchymal stromal cell gene therapy.

BACKGROUND AIMS: Recently, it has been found that effective periodontal regeneration can be induced by bone marrow mesenchymal stromal cell (BMSC) transplantation or local application of basic fibroblast growth factor (bFGF). The aim of the present study was to assess, in dogs, the efficacy of periodontal regeneration via the delivery of BMSC transfected with bFGF to repair destruction of periodontal tissue. METHODS: BMSC from dogs were isolated, cultured and purified via density-gradient centrifugation. Polymerase chain reaction (PCR) was employed to clone bFGF cDNA from human periodontal cells, and the product was then ligated into the eukaryotic expression vector pDC316-IREs-EGFP. BMSC transfected with pDC316bFGF-IREs-EGFP were transplanted into root furcation defects of beagle dogs. After 6 weeks, regeneration in defects was assessed via clinical examination, X-ray, histologic observation and micro-CT analysis. RESULTS: DNA sequence analysis showed that the bFGF sequence of recombinant plasmid pDC316bFGF-IREs-EGFP was consistent with that reported by GeneBank. bFGF expression was detected with Western blotting, and active bFGF in supernatant was also observed. Our animal experiment proved that the regenerating speed of periodontal bone tissue in groups transplanted with BMSC containing the modified bFGF gene was higher than in those transplanted with BMSC alone. CONCLUSIONS: A successfully constructed eukaryotic expression vector containing human bFGF in pDC316bFGF-IREs-EGFP could produce bioactive bFGF in vitro. bFGF overexpression mediated by the recombinant plasmid pDC316bFGF- IREs-EGFP accelerated periodontal regeneration.

Administration of high doses of caffeine increases alveolar bone loss in ligature-induced periodontitis in rats.

BACKGROUND: Although some studies have reported a negative influence of caffeine on bone metabolism, there is no information about its effect on the progression of periodontitis. The aim of this study was to evaluate the effect of high doses of caffeine on ligature-induced periodontitis in rats. METHODS: Twenty-two Wistar rats were assigned to one of the following groups: non-caffeine group (n = 12) = animals without caffeine ingestion; caffeine group (n = 10) = animals ingesting 10 mg/100 g body weight/day of caffeine via drinking water for 56 days. Two weeks after the beginning of caffeine intake, one of the mandibular molar was randomly assigned to receive a ligature, whereas the contralateral molar was left unligated. Forty-two days later, the animals were sacrificed, and the specimens were processed to obtain decalcified sections. The area of periodontal ligament and/or bone loss in the furcation region of the first molars was histometrically determined. RESULTS: Caffeine intake did not have a direct effect on the alveolar bone loss in unligated teeth. But on the ligated tooth, a greater area of bone loss was observed in the animals that ingested caffeine compared to those that did not (P <0.05). CONCLUSION: The present study demonstrated that daily intake of high doses of caffeine may enhance ligature-induced periodontitis progression.

Intrusion of teeth with class III furcation: a clinical, histologic and histometric study in dogs.

AIM: To assess orthodontic intrusion effects on periodontal tissues in dogs' pre-molars with class III furcations treated with open flap debridement (OFD) or with guided tissue regeneration (GTR) associated to bone autograft (BA). MATERIAL AND METHODS: Class III furcations were created in the pre-molars of seven mongrel dogs. After 75 days, teeth were randomly treated with OFD or GTR/BA. After 1 month, metallic crowns were assembled on pre-molars and connected apically to mini-implants by nickel-titanium springs. Teeth were randomly assigned to orthodontic intrusion (OFD+I and GTR/BA+I) groups or no movement (OFD and GTR/BA) groups. Dogs were sacrificed after 3 months of movement and 1 month retention. RESULTS: All class III furcations were closed or reduced to class II or I in the intrusion groups, while 50% of the lesions in non-moved teeth remained unchanged. Intruded teeth presented higher probing depth and lower gingival marginal level than non-moved teeth (p<0.01). Clinical attachment gain was reduced in the intrusion groups by the end of retention (p<0.05). OFD+I presented smaller soft tissue area and larger bone tissue area than other groups (p<0.05). CONCLUSION: Orthodontic intrusion with anchorage via mini-implants improved the healing of class III furcation defects after OFD in dogs. GTR/BA impaired those results.

Influence of residual pockets on progression of periodontitis and tooth loss: results after 11 years of maintenance.

BACKGROUND: Limited evidence exists on the significance of residual probing pocket depth (PPD) as a predictive parameter for periodontal disease progression and tooth loss. AIM: The aim of this study was to investigate the influence of residual PPD >or=5 mm and bleeding on probing (BOP) after active periodontal therapy (APT) on the progression of periodontitis and tooth loss. MATERIAL AND METHODS: In this retrospective cohort, 172 patients were examined after APT and supportive periodontal therapy (SPT) for 3-27 years (mean 11.3 years). Analyses were conducted using information at site, tooth and patient levels. The association of risk factors with tooth loss and progression of periodontitis was investigated using multilevel logistic regression analysis. RESULTS: The number of residual PPD increased during SPT. Compared with PPDor=7 mm 37.9 and 64.2, respectively. At patient level, heavy smoking, initial diagnosis, duration of SPT and PPD>or=6 mm were risk factors for disease progression, while PPD>or=6 mm and BOP>or=30% represented a risk for tooth loss. CONCLUSION: Residual PPD>or=6 mm represent an incomplete periodontal treatment outcome and require further therapy.

Regeneración periodontal (II) / Periodontal regeneration (II)

Las técnicas de regeneración periodontal proporcionan resultados predecibles únicamente en el tratamiento de defectos infraóseos y lesiones de furcación grado II molares mandibulares. Para el éxito, es fundamental un control previo y estricto de los factores etiológicos de la periodontitis (AU)

The periodontal regeneration techniques make up predictables results only on the treatment of infrabody defects and furcation grade II of mandibular molars. Previous and strict control of periodontal etiological factors is necessary for treatment success (AU)

Effect of restraint stress on the progression of experimental periodontitis in rats.

BACKGROUND: A hypothesis of an increased risk for destructive periodontal diseases due to psychological stress has long been promoted. However, the research on stress and periodontal disease is still in its infancy. One of the reasons is thought to be that there is no suitable animal model for investigating the relationship. METHODS: One hundred male Wistar rats were included. A nylon ligature was placed around the second right maxillary molars. The animals were then divided into group S, exposed to a restraint stress for 12 hours/day for up to 10 days, and group N, controls. Ten animals were sacrificed on days 2, 4, 6, 8, and 10. Blood samples were taken, and the blood glucose level and the concentrations of adrenocorticotropic hormone, corticosterone, and adrenaline were measured as the markers of stress. The atrophies of the thymus and the spleen were measured. The furcation area of the second maxillary molars was examined histologically and histometrically. RESULTS: In group S, all values of stress markers were increased, and the thymus and the spleen were atrophied. Whereas group N showed only slight alveolar bone resorption, a marked alveolar bone resorption occurred in group S between days 8 and 10. An increase in beaded nerve terminals occurred around the vessels in the furcation area of group S. CONCLUSION: The results of the present study suggest that the restraint stress modulates the progression of periodontal inflammation and that this rat model is suitable for investigating the association between stress and periodontal disease.

Untreated periodontal disease: a follow-up on 30 cases.

BACKGROUND: Many studies have shown that periodontal disease can be successfully treated. However, there is limited documentation as to what happens when periodontal disease is left untreated. This study examined patients in a private practice who were diagnosed with periodontal disease and did not complete any treatment. The goal was to see what happened to this group of untreated patients. METHODS: Thirty patients with periodontal disease were included in this study. After a mean period of 2.1 years without periodontal treatment, the patients were re-examined and the changes which occurred evaluated. RESULTS: There was a statistically significant increase in probing depth (3.43 mm to 3.95 mm) and attachment loss (4.19 mm to 4.77 mm) and a statistically significant decrease in the number of teeth present (23.37 to 22.67). Twenty-one teeth were lost, which was 3.0% of the teeth present at the time of initial diagnosis. The rate of tooth loss was 0.32 teeth/patient/year. The teeth that were lost had deeper recession, probing depths, and attachment loss than the teeth that were retained. Patient factors evaluated could not be associated with statistically significant changes in the clinical parameters, except that smokers had a greater number of sites gaining > or = 2 mm of attachment and patients with the poorest oral hygiene had a greater percent of sites breaking down. However, certain site specific variables could be associated with statistically significant changes in the clinical parameters. These included sites: with bleeding on probing, associated with molar furcations, on interproximal surfaces, at posterior teeth, with probing depths > or = 3.43 mm, with probing depths > or = 7 mm, attachment loss > or = 7 mm, and teeth with increased mobility. CONCLUSIONS: This group of patients with untreated periodontal disease had greater breakdown and tooth loss than one would expect to see in a group of patients if their periodontal disease was treated.

Impaired healing response of periodontal furcation defects following flap debridement surgery in smokers. A controlled clinical trial.

OBJECTIVES: The purpose of the present parallel-design, controlled clinical trial was to evaluate the treatment outcome of periodontal furcation defects following flap debridement surgery (FDS) procedure in cigarette smokers compared to non-smokers. MATERIALS AND METHODS: After initial therapy, 31 systemically healthy subjects with moderate to advanced periodontitis, who presented at least one Class I or II molar furcation defect, were selected. Nineteen patients (mean age: 40.3 years, 15 males) were smokers (>or=10 cigarettes/day) and 12 patients (mean age: 44.8 years, 3 males) were non-smokers. Full-mouth plaque score (FMPS) and full-mouth bleeding score (FMBS), probing pocket depth (PPD), vertical clinical attachment level (v-CAL), and horizontal clinical attachment level (h-CAL) were assessed immediately before and 6 months following surgery. RESULTS: Overall, statistically significant v-CAL gain was observed in smokers (1.0 +/- 1.3 mm) and non-smokers (1.3+/-1.1 mm), the difference between groups being statistically significant (p=0.0003). In proximal furcation defects, v-CAL gain amounted to 2.3+/-0.7 mm in non-smokers as compared to 1.0+/-1.1 mm in smokers (p=0.0013). At 6 months postsurgery, non-smokers presented a greater h-CAL gain (1.3+/-1.1 mm) than smokers (0.6+/-1.0 mm), with a statistically significant difference between groups (p=0.0089). This trend was confirmed in both facial/lingual (1.4+/-1.0 versus 0.8+/-0.8 mm) and proximal furcation defects (1.2+/-1.3 versus 0.5+/-1.2 mm). The proportion of Class II furcations showing improvement to postsurgery Class I was 27.6% in smokers and 38.5% in non-smokers. After 6 months, 3.4% of presurgery Class I furcation defects in smokers showed complete closure, as compared to 27.8% in non-smokers. CONCLUSIONS: The results of the present study indicated that (1) FDS produced clinically and statistically significant PPD reduction, v-CAL gain, and h-CAL gain in Class I/II molar furcation defects, and (2) cigarette smokers exhibited a less favorable healing outcome following surgery in terms of both v-CAL and h-CAL gain.

Finite element analysis of forces created by root separation and resection modelling.

Natural teeth with a healthy periodontal support exhibit stress transfer when functional forces are applied to them. These stress patterns show considerable variations during differing treatment modalities, which may influence both the tooth and supporting alveolar bone. The purpose of this study was to evaluate variations in the stress transfer under functional loads on first molars with periodontal furcation involvement, which were treated either with by root resection or root separation. This study used a two dimensional mathematical model of a mandibular first molar that was subjected to either a root separation or a root resection procedure. An evenly distributed dynamic load (600 N) was applied on two buccal cusps and distal fossae of the molar in centric occlusion. The analysis was performed using an IBM-compatible computer running standard analysis software. It was found that in the root resection model the stress values were maximum on the centre of rotation, and compressive stresses increased towards the middle of the cervical line. For the root separation model, the maximum shear stress values were observed in the distal portion, and a uniform stress distribution was observed in the mesial portion. Shear stress values for bone increased towards the centre in the bifurcation area. The outcomes of this study may be useful as a guide in clinical restorative procedures.

Assessment of periodontal healing by seeding of fibroblast-like cells derived from regenerated periodontal ligament in artificial furcation defects in a dog: a pilot study.

The regeneration of periodontal supporting tissues lost as a result of disease could be accomplished by repopulating the exposed root surfaces with cells originating from periodontal ligament. Thus, we aimed to assess the seeding of cells derived from regenerated periodontal ligament (RPL) to promote the regeneration in artificial furcation defects of a dog. The fibroblast-like cells were obtained by incubating the explants of RPL tissue taken under a teflon (E-PTFE) membrane. Class II furcation defects were induced on the second and fourth mandibular premolars. Control defects were also included on the contralateral side. A suspension of the fourth passage cells (2 x 10(5) cells) in 0.5 mL of autologous blood coagulum was placed over each furcation area. The healing was histomorphometrically evaluated at the 42nd day postoperatively and expressed as percentage. The healing by new connective tissue attachment with cementum formation was found 75% in the cell-seeding defects whereas, it was 71% in controls. Bone formation was found to fill 51% of furcation defects; however, it was 35% of the defects in the control sites. In this pilot study, we suggested that regeneration of furcation defects by cell-seeding technique may be useful, but further studies are needed to determine the outcome of the procedure.

Computer assisted image analysis methods for evaluation of periodontal wound healing.

The aims of this study were to determine the accuracy of the computer assisted image analysis method and to evaluate its application for the assessment of periodontal wound healing in dogs. Histological material was analyzed with an optic microscope connected to a CCD color camera which transmitted the image to a frame grabber converting the light signals into pixels from which the measurements could be obtained. Twenty sections were read to assess the intra- and inter-examiner reproducibility for the parameters of area filled by new tissue, area of epithelium, area of bone and linear measurements of the cementum. The data were statistically analyzed using the t-test to test the hypothesis that there was no difference between and within examiners. No statistically significant differences were noted (with a confidence interval of 95%) for any parameter when intra-examiner reproducibility was assessed. Similar results were achieved for surface areas when the inter-examiner readings were computed. However, values of linear measurements for cementum showed statistically significant differences between recorders (p < 0.05). Results were consistently uniform and the method demonstrated high accuracy when intra-examiner readings were evaluated.

Effects of furcation involvements on periodontal status and healing in adjacent proximal sites.

BACKGROUND: In a recent study it was found that following non-surgical treatment, probing depth (PD) reduction in proximal sites is significantly less in the presence of a vertical destruction in the adjacent site of the neighboring tooth. The present investigation was undertaken to study whether the presence of a proximal furcation involvement also influences the periodontal conditions in the adjacent site of the neighboring tooth. METHODS: The investigation was conducted as a retrospective study on a consecutive referral population based on full-mouth oral radiographic examinations and PD and plaque score registrations. The statistical analyses were performed on a final sample of 136 patients, with 153 (periodontal status) and 123 (periodontal healing) second maxillary premolars with an adjacent first maxillary molar. RESULTS: Baseline pockets were significantly deeper, relative radiographic attachment levels significantly reduced, and periodontal PD significantly less reduced after non-surgical treatment in the distal sites of second maxillary premolars adjacent to first maxillary molars with a mesial furcation involvement of degree > or = 2, compared to distal sites adjacent to first maxillary molars with a mesial furcation involvement of degree < or = 1. CONCLUSIONS: Periodontal status and healing after non-surgical treatment in proximal sites are negatively influenced by the presence of a deep furcation involvement in the adjacent site in the same proximal space. The presence of a deep proximal furcation involvement should consequently be considered a risk factor for the adjacent site of the neighboring tooth.

The effect of occlusal discrepancies on periodontitis. II. Relationship of occlusal treatment to the progression of periodontal disease.

BACKGROUND: A causal relationship between occlusal discrepancies and periodontal disease has been postulated in the past. However, minimal data are available concerning the effect of treatment of occlusal discrepancies on periodontitis. METHODS: The records from a private practice limited to periodontics were reviewed to find patients who had complete periodontal examination records, including occlusal analysis, that were recorded at least 1 year apart. Patients who fit these criteria were divided into a group that had none of the recommended treatment (untreated n = 30), those who had only non-surgical treatment (partially treated n = 18), and a control group that had completed all recommended treatment (surgically treated n = 41). The data for each tooth of each patient, including occlusal status, were placed in a database and analyzed using the generalized estimating equations method. RESULTS: Worsening in overall clinical condition, as measured by worsening in prognosis, indicated that teeth with no initial occlusal discrepancies and teeth with treated initial occlusal discrepancies were only about 60% as likely to worsen in overall clinical condition over time compared to teeth with untreated occlusal discrepancies. Teeth with untreated occlusal discrepancies were also shown to have a significantly greater increase in probing depth per year than either teeth without initial occlusal discrepancies or teeth with treated initial occlusal discrepancies (P < 0.001). In addition, teeth with untreated occlusal discrepancies had a significant increase in probing depth per year (P < 0.001), whereas teeth without initial occlusal discrepancies and teeth with treated initial occlusal discrepancies had no significant increase in probing depth per year (P > 0.05). CONCLUSIONS: This study provides strong evidence of an association between untreated occlusal discrepancies and the progression of periodontal disease. In addition, this study shows that occlusal treatment significantly reduces the progression of periodontal disease over time and can be an important adjunct therapy in the comprehensive treatment of periodontal disease.

Longitudinal comparison of the periodontal status of patients with moderate to severe periodontal disease receiving no treatment, non-surgical treatment, and surgical treatment utilizing individual sites for analysis.

BACKGROUND: The progression of periodontal disease without treatment and the response of existing periodontal disease to various types of treatment have been studied extensively. Many past studies have used the mean of the patient's probing depths or attachment levels to evaluate disease progression as opposed to following changes in individual sites or teeth. The purpose of the current study was to evaluate the response of individual teeth to treatment or non-treatment. METHODS: The records from a private periodontal practice were reviewed to find patients with complete periodontal examinations that were recorded at least 1 year apart. Patients who fit these criteria were divided into those who had none of the recommended treatment (untreated, n = 30); those who had only non-surgical treatment (partially treated, n = 20); and a control group who had completed all recommended treatment (surgically treated, n = 41). The data for each tooth of each patient were placed in a database and analyzed using the method of generalized estimating equations (GEE) to test for associations between increase or decrease in probing depths and various initial clinical parameters while adjusting for significant confounders. RESULTS: Teeth that received no treatment or non-surgical treatment showed significant increases in probing depths, worsening of prognosis, worsening of furcation involvement, and increases in mobility when compared to surgically treated teeth. Teeth that received surgical treatment showed significant decreases in probing depths. No significant difference was noted between teeth that had no treatment and teeth that had non-surgical treatment. CONCLUSIONS: When individual teeth are used as the basis for analysis, teeth that receive no treatment or non-surgical treatment show a significant worsening of probing depths, furcations, mobility, and prognosis when compared to teeth that receive surgical treatment, while surgically treated teeth show significant improvement in probing depths.

[Periodontal regeneration by application of the porous beta-TCP/BMP artificial bone to Class II furcation defects].

OBJECTIVE: To study the regeneration of periodontal tissue after the application of beta-TCP/BMP artificial bone to class II furcation defects. METHODS: Periodontal defects were produced surgically around premolar teeth in 4 dogs. The flap surgery was performed and the root surfaces were curetted to remove the periodontal ligament and the cementum. A synthetic bioabsorble barrier manufactured from poly DL-lactide was used. The defects were divided into 3 groups (beta-TCP/BMP + PDLLA, PDLLA, control). 12 weeks after surgery, the animals were sacrificed and the teeth with their supporting periodontium were processed for light microscopic evaluation. RESULTS: The definitive evidences of regeneration were founded both in BMP/GTR group and GTR group, but the BMP/GTR group exhibited more new bone formation, cementum deposition occupying the majority of the furcation defects than the other two groups. CONCLUSION: It was concluded that the beta-TCP/BMP artificial bone can be used in GTR technique to promote periodontal regeneration.