Focus on periodontal disease and colorectal carcinoma.

Diagnosis of focal disease, the theory that the human oral microbial (HOM) could affect the onset and development of systemic diseases, was very popular in the past, but the lack of scientific evidence has led to the abandonment of this idea. Interestingly, increasing evidence over the past 3 or so decades suggests that HOM can indeed serve as a reservoir for systemic dissemination of pathogenic bacteria and their toxins in distant body sites, favouring the developments of malignant tumours. Malignant tumours are complex communities of oncogenically transformed cells with aberrant genomes, associated non-neoplastic cells including immune and stromal cells, and sometimes HOM, including bacteria and viruses. Recent data suggest that HOM and periodontal disease play an active role in the pathogenesis of colorectal cancer, in fact HOM has been found within the colorectal cancer microenvironment, and the composition of the HOM was different from that of adjacent non-neoplastic tissue. An association of fusobacterium nucleatum with the colonic mucosa of colorectal cancer has been proven. Several questions thus arise. Is periodontal disease a risk factor for colorectal carcinoma? Given the connectivity of the digestive tract, could fusubacterium nucleatum or other HOM be involved in additional gastrointestinal disorders? Furthermore, based on the "mobility" of Fusubacterium nucleatum and the omnipresence of cadherins, could this organism be involved in cancers beyond the gastrointestinal tract? Answers to these questions will shed new lights on the role of the HOM in onset of diseases.

Mastication induces long-term increases in blood perfusion of the trigeminal principal nucleus.

Understanding mechanisms for vessel tone regulation within the trigeminal nuclei is of great interest because some headache syndromes are due to dysregulation of such mechanisms. Previous experiments on animal models suggest that mastication may alter neuron metabolism and blood supply in these nuclei. To investigate this hypothesis in humans, arterial spin-labeling magnetic resonance imaging (MRI) was used to measure blood perfusion within the principal trigeminal nucleus (Vp) and in the dorsolateral-midbrain (DM, including the mesencephalic trigeminal nucleus) in healthy volunteers, before and immediately after a mastication exercise consisting of chewing a gum on one side of the mouth for 1 h at 1 bite/s. The side preference for masticating was evaluated with a chewing test and the volume of the masseter muscle was measured on T1-weighted MRI scans. The results demonstrated that the mastication exercise caused a perfusion increase within the Vp, but not in the DM. This change was correlated to the preference score for the side where the exercise took place. Moreover, the basal Vp perfusion was correlated to the masseter volume. These results indicate that the local vascular tone of the trigeminal nuclei can be constitutively altered by the chewing practice and by strong or sustained chewing.

Five-year outcome of bone remodelling around implants in the maxillary sinus: assessment of differences between implants placed in autogenous inlay bone blocks and in ungrafted maxilla.

The placement of implants in the posterior maxillary area is considered a reliable procedure, offering recognized rehabilitative advantages. The aim of this study was to evaluate the performance of dental implants placed in the sinus floor augmented with a block autograft by comparing the outcomes over 5 years with those of dental implants positioned in non-augmented bone. This retrospective cohort study included 16 patients who had undergone prosthetic rehabilitation supported by dental implants between 2000 and 2006. One implant per patient was included and assigned to one of two predictor groups: grafted versus ungrafted maxillary sinus. Changes in marginal bone level (MBL) and apical bone level (ABL) over time, at 1, 3, and 5 years, were the primary outcome variables. Appropriate pair-wise comparison tests were performed. No significant differences were seen with regard to ABLs and among times between the grafted group (nine implants) and the ungrafted group (seven implants). Significant marginal bone resorption was found over time, primarily at the buccal aspect, in both study groups. The bone surrounding the apex of dental implants appeared stable after sinus augmentation in the grafted area. The behaviour of the two groups with regard to loss of MBLs over time was very similar.

Estudio experimental sobre la utilización de células madre humanas en la terapia de los defectos periodontales: resultados preliminares / Experimental study on the use of human stem cell therapy in periodontal defects: Preliminary results

La destrucción del ligamento periodontal y de la cresta alveolar causada por la enfermedad periodontal, constituye la principal causa de pérdida dentaria en pacientes adultos. Resulta difícil que la terapia en la enfermedad periodontal avanzada lleve a una restitutio ad integrum de la estructura que se ha perdido por la imposibilidad de regenerar la correcta anatomía del sistema perdido. Este estudio tiene como objetivo evaluar el potencial y la estabilidad de la utilización de células madre mesenquimales (MSC) en la regeneración periodontal de la estructura original. Su objetivo es determinar un método de regeneración de la estructura periodontal original que se ha perdido después de la enfermedad periodontal, cerca de los elementos dentales vitales sin patologías correlacionadas. Este estudio constituye una experimentación de fase 1 aprobada por el Instituto Superior de Salud sobre un número limitado de pacientes, cuyo objetivo principal será la evaluación de la biocompatibilidad y toxicidad in vivo de las células madre mesenquimales diferenciadas en sentido osteoblástico, sostenidas por andamios de colágeno biomiméticos en pacientes afectados por periodontopatía severa. El protocolo describe el transplante de células madre mesenquimales derivadas de muestras de un aspirado percutáneo de médula ósea. Las células de la médula ósea son manipuladas ex vivo para el aislamiento de la población de células madre mesenquimales. Las células madre adultas son diferenciadas en las líneas celulares que forman el sistema periodontal, sucesivamente inducidas y cultivadas en andamios adecuados definidos en base a características propias con el fin de obtener una distribución uniforme de las líneas celulares, e injertadas en el sitio receptor estimulado adecuadamente hasta la degradación de los andamios, en un tiempo suficiente para garantizar la estabilidad de las diferentes líneas celulares y la recíproca interacción, con el fin de recrear la correcta anatomía estructural del periodonto perdido. Después de una fase de expansión celular, estas células se introducen en una estructura biomimética (andamios en colágeno), y se inducen a la diferenciación en sentido osteogénico. El producto final que consta de andamios y células mesenquimales diferenciadas en sentido osteoblástico, se instala por último en el defecto alveolar periodontal. La experimentación se basa en la posibilidad de utilizar células madre mesenquimales autólogas a partir de la médula ósea humana. La finalidad es la de estimular la regeneración de PDL cerca de la pared radicular y la formación de hueso nuevo sobre el PDL, beneficiándose de las técnicas de regeneración-reconstrucción ósea, de manera que se recree la correcta anatomía periodontal. Los resultados presentados en este trabajo conciernen el primer paciente tratado con esta metodología y afectarán los estudios siguientes para la prueba con una cobertura más amplia (AU)

Destruction of periodontal ligament and alveolar ridge rerorption caused by periodontal disease is the leading cause of tooth loss in adults. Therapy of advanced periodontal disease leads for a total recovery of the structure lost by the inability to regenerate the pristine correct anatomy system. The aim of this study is to assess the potential use of mesenchymal stem cells (MSCs) in the regeneration of original periodontal structure. This study is an experimental phase 1 approved by the Italian Institute of Health on a limited number of patients; main objective will be to assess the biocompatibility and toxicity in vivo of differentiated mesenchymal stem cells into osteoblast sense, supported by biomimetic collagen scaffolds in patients with severe periodontal disease. The protocol describes transplantation of mesenchymal stem cells derived from samples of percutaneous bone marrow aspirate. The bone marrow cells are manipulated ex vivo to isolate mesenchymal stem cell population. After a phase of cell expansion, these cells are induced to differentiate into periodontal system cell lines in a biomimetic structure (collagen scaffold). Induction and culturation in an appropriate scaffold defined on specific characteristics lead to obtain an uniform distribution of cell lines. After 28 days Scs are grafted into the defect site of the patient. Scaffold degradation time will ensure stability of the different cell lines and reciprocal interaction, in order to recreate the correct structural anatomy of periodontium lost. The purpose is to stimulate the regeneration of PDL near the root wall and new bone formation on the PDL, benefiting from the techniques of bone regeneration, reconstruction, as to recreate the pristine periodontal anatomy. The results presented in this paper concern the first patient treated with this method and will affect following studies for test for a wider coverage (AU)

Volume changes of autogenous bone grafts after alveolar ridge augmentation of atrophic maxillae and mandibles.

The aim of the present retrospective chart review was to determine the relationship between nonvascularized osseous graft remodeling and the three-dimensional (3D) features of grafts and recipient sites, the anatomical recipient regions and different graft sources. 32 iliac crest or chin grafts were onlay-positioned in the mandible or maxilla of 14 patients. CT scans, taken before implant positioning and after 1 year, revealed a mean volume resorption of 35-51%. For iliac crest grafts, the average resorption was 42% when the onlay was positioned in the anterior maxilla and 59% when it was positioned in the posterior mandible. Spearman correlation and 3D interpolation analysis revealed, for both iliac crest groups, a moderate or advanced remodeling pattern depending on 3D features, namely graft thickness and shape, basal bone volume of recipient site, and the basal bone/graft volume ratio of the recipient site. No statistically significant differences were found between the recipient and donor site groups. Retrospective analysis of the data indicates that iliac crest grafts, onlay-positioned on adequate basal bone volume, may register a reduced volume remodeling when shaped thick in the anterior maxilla or rounded and convex, on the external surface, in the posterior mandible.

Clinical survey of neurosensory side-effects of mandibular parasymphyseal bone harvesting.

The aim of the present survey was to assess neurosensory disturbances and/or tooth-pulp sensitivity losses after mandibular parasymphyseal bone-harvesting procedures. Twenty-eight harvesting areas in 16 patients were surveyed. Mucosal and skin sensitivity of the chin/lower lip, divided into four regions, were determined via Pointed-Blunt and Two-Point-Discrimination Tests. Pulp sensitivity of the mandibular teeth from the left second bicuspid to the right second bicuspid was tested by cold vitality preoperatively and 12 months postoperatively. Teeth were grouped according to sensitivity alterations and distance from the harvesting defects, as measured on CT scans, and statistically significant differences sought. At 12 months, 29% of preoperatively vital cuspids overlying the harvesting defects revealed pulp-sensitivity losses; no patient reported anaesthesia or analgesia; hypoaesthesia was present in 4% (8 sites; 2 patients), hypoalgesia was present in 3% (5 sites; 2 patients) and Two-Point-Discrimination Tests yielded pathologic responses in 5% of tested areas (10 sites; 4 patients). Teeth with and without pulp sensitivity changes were statistically indistinguishable regarding distances between root apices or mental foramen and the harvesting defect. The loss of pulp sensitivity in any tooth cannot be predicted simply on the basis of the distance between its apex and the harvesting osteotomy line.

Histological and clinical survey of polylactic-polyglycolic acid and dextrane copolymer in maxillary sinus lift: a pilot in vivo study.

Of various proposed alternatives to autogenous bone, a synthetic, degradable copolymer of PLA-GLA and dextrane seems to be a promising biomaterial for maxillary sinus lift. Consecutive partially edentulous patients showing severe monolateral posterior maxillary atrophy were treated via sinus lift using PLA-GLA-dextrane copolymer as the sole filler. Delayed implant positioning was performed and cores of regenerated tissues and native bone controls were retrieved and evaluated by light and electron microscopy, histomorphometry, microhardness and qualitative X-ray analysis. Seven sinuses in 7 patients were augmented with PLA-GLA-dextrane copolymer. Six to nine months after the copolymer 'graft', 17 bone cores were retrieved: all histological sections contained newly synthesized, mineralized material and new bone in various stages of development. Histomorphometry revealed average Trabecular Bone Volume (TBV) values ranging from 51% (6 months) to 77% (9 months). Backscattered scanning electron microscopy (BSE) in experimental and control samples confirmed histology findings. Microhardness values suggested newly formed bone at nine months was not as hard as native bone. Ca and P content was similar in 9-month regenerated and native bone. Seventeen implants were inserted in the second stage of surgery: resulting Implant Success (SR) and Cumulative Success (CSR) up to 3 years were 100% following Albrektssons criteria. Sinus lift augmentation using PLA-GLA-dextrane copolymer as the sole filler resulted in uneventful surgeries. New bone formation was evident histologically and its maturation was still in progress after 9 months. Successful, staged implant positioning was achieved in regenerated tissue.

Behavior of SaOS-2 cells cultured on different titanium surfaces.

Surface properties may affect the clinical outcome of titanium dental implants. The aim of the present study was to investigate the effects of 3 different titanium surfaces-smooth (S), sandblasted (SB), and titanium plasma-sprayed (TPS)-on proliferation, differentiation, and apoptosis of human osteoblast-like cells, SaOS-2. Cell proliferation was significantly (p < 0.05) higher on the S surface, and synthesis of extracellular matrix proteins was more abundant on TPS and SB than on S surfaces. Analysis of integrin receptors showed a higher expression of alpha2, alpha5, alphaVbeta3, and ss1 on TPS as compared with SB and S surfaces. An increase in alkaline phosphatase activity was detected only on SB and TPS surfaces. Analysis of cell apoptosis did not demonstrate any significant difference among the 3 different surfaces. The results indicate that titanium surface topography affects proliferation and differentiation of osteoblast-like SaOS-2 cells, suggesting that surface properties might be important for bone response around dental implants in vivo.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) induces the osteoblastic differentiation of the human osteosarcoma cell line SaOS-2.

The Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) is a hematopoietic growth factor that regulates the in vitro and in vivo proliferation and differentiation of hematopoietic cells through the interaction with a specific heterodimeric receptor complex (GM-CSFR), consisting of an alpha and a beta chain with molecular weights of 80 and 120 KDa, respectively. We have studied the expression of the GM-CSFR (alpha chain) on the surface of the human osteosarcoma cell line SaOS-2 and the in vitro effects of different concentrations (10, 100, and 200 ng/ml) of GM-CSF on GM-CSFR expression and the biological activity of SaOS-2 cells. Our data show that SaOS-2 cells express GM-CSFR and that GM-CSF can down-regulate the expression of its own receptor on these cells. Furthermore, to evaluate the biological effects of GM-CSF on SaOS-2 cells, we have investigated cell proliferation and differentiation of these cells treated with different doses of the growth factor through: (1) a morphological analysis of typical osteoblast differentiation markers such as osteopontin and BSP-II; (2) measurement of alkaline phosphatase (ALP) activity; (3) production of bone ECM components (collagen I, fibronectin, tenascin, and laminin); (4) production of interleukin-6 (IL-6) and osteocalcin in the culture medium. The results show that the in vitro treatment of SaOS-2 cells with recombinant human GM-CSF causes a decreased cell proliferation and an increased production of osteopontin, BSP-II, ALP, IL-6, and most but not all ECM components. These findings suggest that GM-CSF can regulate proliferation and differentiation of osteoblast-like SaOS-2 cells and could also play an unexpected role in the maturation of bone tissue.

[Biofilms of the oral cavity. Formation, development and involvement in the onset of diseases related to bacterial plaque increase]. / I biofilm del cavo orale. Formazione, sviluppo e implicazioni nell'insorgenza delle malattie correlate all'accumulo di placca batterica.

Biofilm is defined as a community of bacteria intimately associated with each other and included within an exopolymer matrix: this biological unit exhibits its own properties, quite different in comparison with those showed by the single species in planktonic form. The oral cavity appears as an open ecosystem, with a dynamic balance between the entrance of microrganisms, colonisation modalities and host defences aimed to their removal: to avoid elimination, bacteria need to adhere to either hard dental surfaces or epithelial surfaces. The oral biofilm formation and development, and the inside selection of specific microrganisms have been correlated with the most common oral pathologies, such as dental caries, periodontal disease and peri-implantitis. Many of these bacteria are usual saprophytes of the oral environment, that, in particular situations, can overcome and express their virulence factors: to better understand the mechanisms of these pathologies it's necessary to know the complex interactions between all the bacterial species inside the biofilm and host tissues and responses. The present paper is a review of the most significant studies on the biofilm development modalities, their correlations with either health or illness of the oral cavity, the bacterial co-aggregation strategies and the biofilm response to antimicrobial agents.

[Periodontal disease and occlusal trauma: a still debated controversy? A review of the literature]. / Malattia parodontale e trauma da occlusione: una controversia ancora aperta?

In the "Glossary of Periodontics Terms" written by the American Academy of Periodontology, the occlusal trauma is defined as "an injury to the attachment apparatus as a result of excessive occlusal forces". Nowadays, the effects of occlusal trauma on tooth support tissues, the onset and the progression of periodontal disease are still debated: many commonplaces have been disproved, but some doubts and not yet clear points remain, even owing to the difficult diagnosis of the presence and the real clinical impact of a traumatic occlusion. Then, ethical reasons prevent researchers from prospective clinical trials. At the beginning of the last century occlusal trauma has been supposed to be an etiologic factor of "alveolar pyorrhea", but several studies attending more strict scientific criteria failed to prove such correlation. On the basis of the bacterial genesis of periodontal disease, researchers started evaluating the possible effects of occlusal discrepancies on incidence, progression and treatment outcomes of periodontitis, but all the results underlined the more relevant role played by micro-organisms. The present review of the literature runs through this controversy again, analysing the most significant studies published.

Tetracycline fibres used to control bacterial infection during guided tissue regeneration (GTR).

AIMS: The colonization of suspected periodontal pathogens during the healing of periodontal defects treated by guided tissue regeneration (GTR) with e-PTFE membranes and tetracycline fibers was investigated. METHODS: Fifteen patients, each with one pair of angular periodontal bone defects of comparable size and morphology were recruited for the study. In a matched-pair study design, the test defects were treated with e-PTFE membranes in combination with tetracycline fibers, while control defects were treated with e-PTFE membranes alone. Microbiological specimens were taken from control as well as from test sites preoperatively (T0), intraoperatively (T1), two weeks after surgery (T2) and from membranes at time of removal (T3). Cultural methods were used to identify the following species: Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn) and Actinobacillus actinomicetemcomitans (Aa). RESULTS: At baseline and T1, none of the suspected periodontal pathogens were detected at test or control sites. Levels of P. intermedia and F. nucleatum, as mean percentages of total culturable microflora, were detected at levels significantly higher in control sites than test sites at times T2 and T3. CONCLUSIONS: Findings from this study suggest that e-PTFE membranes are frequently colonized by periodontal pathogens, and that bacterial colonization of healing sites after GTR procedures can be kept under control with a controlled delivery system releasing tetracycline.

[Bacterial virulence in the etiology of periodontal diseases]. / La virulenza batterica nella etiologia delle malattie parodontali.

Strong relationships have been very often described between various form of periodontal disease (PD) and certain bacterial species, so that nowadays periodontal disease is recognized as an infectious disease. Destruction of periodontal supporting tissues happens as a response to very intricate host-parasite interactions. When the clinician will be able to fully understand and identify such phenomena it would be possible to succeed in a properly diagnosis and control of the active phase of periodontal disease. The first step in such a direction would be to analyze the common characteristic of some bacterial species, the so called suspected periodontopathogens. Such species namely Gram-negative, associated with the outbreak of periodontal disease have in common the capacity to disrupt the integrity of the host defences by means of the so called virulence factors. These factors may enhance the bacterial colonization or may interfere with the host response that ultimately results in periodontal support breakdown. The present review focuses on the virulence factors of the main suspected periodontopathogens evaluating the effects on the host immune response and directly on the periodontal tissues.

[Implants in partially edentulous patients with history of periodontal disease]. / Impianti in pazienti parzialmente edentuli con storia di malattia parodontale.

BACKGROUND: Microbiota associated with periodontal diseases were also associated with periimplant diseases. The purpose of this study was to determine the clinical status and composition of subgingival microbiota of implants and natural teeth in a group of partially edentulous patients with history of periodontal disease. METHODS: 38 partially edentulous patients with history of periodontal disease, treated with dental implants, were selected for this study. Patients selected for the study were in good health condition and did not take any antibiotics in the last six months. One year after second stage surgery a total of 72 implants and 38 teeth underwent clinical and microbiological examination. Clinical parameters were PD, PAL, PI and GI. Subgingival plaque samples were analyzed by dark-field microscopy and cultural analysis. RESULTS: Clinical parameters didn't show any significant differences between periodontal and periimplant tissues. Dark-field microscopic examination showed higher prevalence of rods and spirochetes around implants than around teeth. There were no differences detected by cultural examination in the subgingival microbiota at peri-implant and periodontal sites. CONCLUSIONS: Findings from this study showed no differences between implants and teeth in partially edentulous patients with history of periodontal disease one year after second stage surgery. Implants were colonized by microbiota similar to that observed around teeth and were well-maintained in patients with a history of periodontitis.

Longitudinal study of dental implants in a periodontally compromised population.

BACKGROUND: The purpose of this longitudinal study was to determine the clinical status and the composition of the subgingival microbiota of dental implants and natural teeth in patients with a history of periodontitis. METHODS: Twenty-five partially edentulous patients treated for moderate to advanced adult periodontitis and having a total of 42 implants participated in this 3-year study. The assessment of clinical status was done 1, 2, and 3 years after prosthetic loading (T1, T2, and T3, respectively). Clinical parameters evaluated included probing depth (PD), clinical attachment level (CAL), gingival index (GI), and plaque index (PI). The subgingival microbiota at peri-implant and periodontal sites were analyzed at T1 and T2. RESULTS: No significant difference in clinical parameters between implants and teeth and within the 2 groups between different time points was observed through the study. PD and CAL measurements of sampled periodontal and peri-implant sites did not show any statistically significant difference through the study and between the 2 groups. PI of sampled periodontal sites showed a statistically significant improvement during the study. From the morphological observation of the subgingival microbiota, a significant difference in the composition of motile rods between implants and teeth was found at T1. There were no differences detected in the subgingival microbiota, culturally identified at peri-implant and periodontal sites for the duration of the study. CONCLUSIONS: In conclusion, implants were colonized by the indigenous periodontal microbiota and were well maintained in patients with a history of periodontitis. No significant association between progressing or non-progressing periodontal or peri-implant sampled sites in terms of loss of attachment and infection with at least one of the searched periodontal pathogens was found, suggesting that the presence of putative periodontopathogens at peri-implant and periodontal sites may not be associated with future attachment loss or implant failure.

A clinical comparison of the efficacy and efficiency of two professional prophylaxis procedures in orthodontic patients.

This study compared the efficacy and efficiency of two professional prophylaxis procedures in orthodontic patients performing different oral hygiene regimens: the air powder polishing system (APP), and the rubber cup and pumice (RCP) technique. Sixty-two patients were divided into two groups: group I included 40 subjects who did not use any chlorhexidine mouthwash and group II comprised 22 subjects who regularly rinsed with a chlorhexidine mouthwash (at a 0.12 per cent concentration) and showed increased tooth staining. Using a split-mouth experimental design, the buccal and lingual tooth surfaces were cleaned in half of the mouth by the APP and in the opposite half by the RCP technique. Tooth surfaces were scored before (PRE) and after (POST) the experimental procedures for the plaque index (PI), and for the presence of tooth staining. In addition, the treatment time required by each procedure was recorded. In test group I, significant reductions in the PI after APP and RCP were observed. Likewise, in test group II, both procedures significantly reduced the baseline PI values. In both experimental groups, the percentage of stained sites significantly decreased after APP and RCP, but in test group II, APP seemed to be more effective than RCP. In addition, APP required significantly less time than RCP to remove dental plaque and staining. These data show that both professional prophylaxis procedures are effective in orthodontic patients, with APP being the most time-efficient technique and the most effective method for removal of tooth staining.

Microbiotica associated with refractory periodontis. Prevalence and antibiotic susceptibility.

BACKGROUND: The aim of the present study was to analyze the composition of subgingival microflora in patients with refractory periodontitis and to evaluate the antimicrobial sensitivity of isolated periodontopathic microorganisms to different antibiotics. METHODS: Eleven subjects with a mean age of 46.4 years were selected for the present study. All had been treated for periodontal disease in the past. After further disease progression patients were included in this study. Eight subgingival plaque samples per patients were collected for cultural analysis. RESULTS: "Black pigmenting anaerobic bacilli" were the pathogenic microorganisms more frequently isolated. The findings from antibiotic susceptibility test showed that high number of bacteria associated with refractory periodontitis resulted resistant to erythromycin, metronidazole and tetracycline. The most effective antibiotics were ciprofloxacin, amoxicillin-metronidazole and amoxicillin-clavulanic acid. CONCLUSIONS: Microbiological analysis and antibiotic susceptibility test should be considered important tools in the management of patients with poor clinical response to conventional periodontal treatment.

Bacterial colonisation during GTR treatment. A longitudinal analysis.

UNLABELLED: The purpose of the present study was to evaluate the long-term biological and clinical effects of a controlled delivery system releasing tetracyclines during the healing of interproximal periodontal defects treated by the technique of guided tissue regeneration (GTR) using e-PTFE membranes. METHODS: Fifteen patients, each with two comparable interproximal periodontal defects, underwent surgical treatment with e-PTFE membranes in conjunction with tetracycline fibres at the test site and e-PTFE membranes alone at the control site. Microbiological specimens were taken from each site treated at baseline (T0) and one year after surgery (T4). Plaque index (PI), gingival index (GI), pocket depth at probing (PD) and attachment level at probing (PAL) were recorded at baseline (T0) and one year after surgery (T4). The presence of selected pathogenic microbial species, Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium Nucleatum (Fn) and Actinobaccillus Actinomicetemcomitans (Aa), was investigated and these species were identified by cultural methods. RESULTS: No statistically significant difference in the level of periodontal pathogens was detected between the test and control sites at time T4. Likewise, no significant clinical difference between the test site and the control site was detected at time T4. CONCLUSIONS: The results suggest that tetracycline fibres used in conjunction with e-PTFE membranes do not provide and further clinical and microbiological improvement or effect the healing of periodontal defects one year after GTR treatment.

Periodontal status and subgingival microbiota of insulin-dependent juvenile diabetics: a 3-year longitudinal study.

This study examined for 3 years the changes in periodontal status and the possible correlations with selected subgingival microbiota and diabetic conditions in a group of 16 insulin-dependent diabetes mellitus (IDDM, JD) patients as compared with their 16 healthy cohabiting siblings (HS). JD patients were monitored every 3 months for levels of glycosylated hemoglobin (HbA1C). Clinical and microbiological parameters were measured 6 weeks before drawing blood to determine levels of HbA1C. Periodontal parameters were measured at baseline (TO), year 2 (T2), year 3 (T3) and included: probing depth (PD), attachment level (AL), sulcus bleeding index (SBI), and plaque index (PI). Two sites in each patient were selected for microbial samples: a mesio-facial aspect of the maxillary right first molar (defined as constant site, CS) and a site with the greatest probing depth (defined as deepest site, DS). Microbial samples were analyzed by culture techniques. No significant differences in clinical parameters were found between diabetics and healthy siblings at any examination. The SBI in the non-diabetic group at T2 and at T3 was significantly lower than at baseline. PD and AL of constant sites in the diabetic group at T3 were significantly higher than baseline. There was a significant increase in Prevotella intermedia at T3 as compared with baseline for deepest sites in the diabetic group. Cluster analysis revealed, in a former study, two clusters (IV and V) at baseline which were significantly different from the overall mean regarding composition of Porphyromonas gingivalis and Capnocytophaga spp. They were not significantly different for periodontal parameters from TO to T3. These data would suggest no significant differences in clinical parameters between the diabetics and non-diabetic siblings throughout this 3-year longitudinal study.

Craniomandibular disorders and orthodontic treatment need in children.

Two hundred and forty subjects (113 boys and 127 girls), divided in three age groups, 7, 11, and 16 years were interviewed and clinically examined to estimate the prevalence of CMDs and the need for functional treatment, and to compare the functional status of the stomatognatic system in two subgroups: those judged to need orthodontic treatment and those judged not to need orthodontic treatment. Signs and symptoms of craniomandibular disorders were quite common and, in most cases, mild. There were significant differences in prevalence of CMDs between sexes. Only 3.7% of the patients were judged to need some functional treatment for CMDs. Trauma to the facial area and headaches were significantly associated with signs and symptoms of CMDs. No indication was found that oral parafunctions produce CMDs. No greater prevalence of CMDs signs and symptoms was found in subjects who needed orthodontic treatment than in subjects who did not need orthodontic treatment. In conclusion, preliminary results of this ongoing study support the contention that the high prevalence of signs and symptoms of CMDs is not really a measure of masticatory dysfunction, and that malocclusion does not appear to cause CMDs and/or to increase craniomandibular treatment need in a young population.