Periodontal healing in humans using anorganic bovine bone and bovine peritoneum-derived collagen membrane: a clinical and histologic case report.

The authors report the clinical and histologic data on the healing of a severe periodontal lesion obtained in a one-walled intrabony defect using anorganic bovine bone under a bovine peritoneum-derived collagen membrane. Eight months after surgery, a bone-like tissue replaced the lost tissues. A biopsy of this tissue was carried out. In the part of the specimen closer to the residual bony wall of the original defect, anorganic bone particles (ABP) appeared to be surrounded by a layer of newly formed bone; its osteocyte lacunae were colonized by osteocytes from the host, and actively secreting osteoblasts were observed in many microscopic fields. No resorption phenomena were observed in the ABP Newly formed cementum with actively secreting cementoblasts was present on the tooth surface, and well-oriented fibers inserting in both newly formed cementum and bone were observed. In an area far from residual bone, all ABP did not appear to be surrounded by newly formed bone. Osteocytic lacunae appeared not to be colonized by cells, and ABP was surrounded by dense connective tissue without osteoblasts near the grafted particles. A very limited amount of newly formed bone, without relations with ABP, was observed close to the root surface. From a clinical point of view, anorganic bone in association with a collagen membrane can be effective in the treatment of bony defects characterized by an unfavorable architecture. From a histologic point of view, the clinical appearance of bone regeneration is not always confirmed in the part of the defect far from the bony walls.

Immediate implantation in fresh extraction sockets. A controlled clinical and histological study in man.

BACKGROUND: Early implantation may preserve the alveolar anatomy, and the placement of a fixture in a fresh extraction socket helps to maintain the bony crest. Although a number of clinical studies exist, no histological reports show the outcome of implantation in fresh extraction sockets without the use of membranes in humans compared to implants placed in mature bone. METHODS: Forty-eight healthy patients, receiving at least 4 fixtures in each of 2 symmetrical quadrants, underwent placement of 1 experimental fixture placed in a fresh extraction socket (TI) and 1 contralateral fixture in mature bone (CI). TI were placed after atraumatical tooth extraction, with a surgical site at the apex of the socket and a tight contact between the fixture and the socket's walls, but without the use of filling materials or membranes. The flap was coronally repositioned to obtain primary wound closure. Immediately after surgical intervention, a standardized periapical radiograph was taken. Second-stage surgery was done after 6 months. Six months after the second surgery, a second standardized periapical radiograph was taken and clinical parameters (bleeding and plaque index) recorded. Marginal bone loss (MBL) from the time of implant placement to the time of fixture removal was calculated by comparing periapical radiographs. TI and CI were then removed by a hollow drill to obtain histological specimens. Non-demineralized sections were stained by acid fuchsin and toluidine blue, and by von Kossa to evaluate the degree of bone mineralization. The percentage of direct implant-bone contact (DBC) was calculated by a computerized microscopic digitizer. RESULTS: No significant differences in the clinical and radiographic parameters were observed between the 2 experimental categories. There was no statistically significant difference between TI and CI for DBC either in the maxilla or in the mandible. No connective or fibrous tissues were present around TI or CI. Bone resorption was not present in any of the histological sections. CONCLUSIONS: The present study shows that when a screw-type dental implant is placed without the use of barrier membranes or other regenerative materials into a fresh extraction socket with a bone-to-implant gap of 2 mm or less, the clinical outcome and degree of osteointegration does not differ from implants placed in healed, mature bone.

Aspartate aminotransferase activity in crevicular fluid from dental implants.

BACKGROUND: Aspartate aminotransferase (AST) is an enzyme normally confined to the cytoplasm of cells, but released to the extracellular environment upon cell death. Its levels are associated with the severity of experimental gingivitis and the loss of periodontal attachment. The aim of the present study was to investigate the presence and activity levels of AST in peri-implant crevicular fluid (PCF) from healthy and diseased endosseous implants in order to assess if AST in PCF can be further studied as a possible objective diagnostic aid in oral implantology. METHODS: Eighty-one fixtures from 81 systemically healthy subjects were divided into 3 groups, 27 healthy implants (HI), 27 implants with mucositis (MI) and 27 implants affected by peri-implantitis (PI) according to well-defined clinical and radiographic criteria. PCF was collected by the insertion of a #40 standardized endodontic paper point to the base of the crevice or pocket for 30 seconds. AST activity was determined spectrophotometrically at 25 degrees C. The results were expressed as AST Units/ml in PCF. RESULTS: An AST activity was detected in each sample from HI, MI and PI. The mean AST activity in HI was 0.26 +/- 0.16 U/ml; in MI, 0.38 +/- 0.27 U/ml; in PI, 0.62 +/- 0.29 U/ml. ANOVA showed that the difference among HI, MI, and PI was statistically significant at P <0.01 level. Post-hoc tests demonstrated that a significant difference in AST activity existed between HI/PI (t = 5.14; P<0.01) and MI/PI (t = 3.09; P<0.01). No statistically significant difference was found between HI/MI (t = 1.07; P >0.1) AST activity was significantly (P <0.01) associated with probing depth (r = 0.55), the amount of bone loss (r = 0.60) and bleeding on probing (r = 0.67). When the threshold for a positive AST test was set > or =0.4 U/ml, a sensitivity = 0.81 and a specificity = 0.74 were found in the detection of peri-implantitis; the positive predictive value was 61% and the negative predictive value was 88%. CONCLUSIONS: Within the limits of this study, our results may suggest that PCF analysis could be further investigated in longitudinal studies as a suitable diagnostic strategy in the evaluation of dental implants.

Prevalence of Actinobacillus actinomycetemcomitans and clinical conditions in children and adolescents from rural and urban areas of central Italy.

BACKGROUND: The aim of this study was to report on the prevalence of Actinobacillus actinomycetemcomitans (Aa) and the periodontal clinical conditions in children and adolescents from a rural area of central Italy compared with the ones from an urban area of the same region. METHOD: The study population consisted of 780 systemically healthy children, aged 6-14 years inhabiting the county of Chieti. 505 children attended 3 primary and 2 secondary schools from a rural area whereas 275 individuals attended 1 primary and 1 secondary school from the city of Chieti. The 2 provincial areas present a great difference in socioeconomic level and cultural background. Clinical examination consisted of recording the % of gingival sites positive for the presence of plaque (P1+), bleeding on probing (BOP+), mean probing depth (PD) from each primary or permanent tooth fully erupted in the oral cavity. Loss of periodontal attachment (AL+) was evaluated only in interproximal sites. AL+ subjects were distinguished in juvenile periodontitis (JP) prepubertal periodontis and early periodontitis (EP) patients. 8 gingival sites were microbiologically sampled in each subject and cultured, after pooling, for the presence of Aa. RESULTS: 30.3% of rural subjects, were positive for the presence of Aa, the difference from urban children (16%) being statistically significant (p=0.01) irrespective of gender and age. Aa showed a significantly (p=0.006) higher mean proportion in subgingival plaque samples from rural children (0.13% versus 0.02%). Loss of periodontal attachment in at least one site was found in 18 rural children (3.56%) (3 JP; 15 EP) and 2 urban girls (0.72%)(1 JP; 1 EP). No significant differences for AL were observed within the rural group according to the gender and age differentiation. In the urban group, both AL+ subjects were Aa+, while among children from rural areas all 3 JP and 13 EP subjects were Aa+. Rural subjects evidenced significantly worse clinical parameters with respect to urban children (% PI+ sites: p=0.000; % BOP+ sites: p=0.010; mean PD: p=0.000.) The relative risk for AL+ sites was significantly greater (2.42) in rural subjects harboring Aa in subgingival plaque. Similarly, the presence of Aa in subgingival plaque was related to a greater risk of more than 50% of BOP+ gingival sites in both rural and urban subjects (1.45 and 8.40, respectively). CONCLUSIONS: Results of this study suggest that Aa colonization in children and adolescents from central Italy is affected by socioeconomic and cultural factors; these factors also affect the periodontal condition of the subjects.

Bacteriological and clinical follow-up of periodontal pockets during a topically applied 1% metronidazole-gel therapy in patients with adult periodontitis.

The aim of this study was to evaluate the clinical and bacteriological effects of the intrasulcular application of a 1% metronidazole-gel (repeated administrations outdistanced of 7 days weeks long) currently employed in dermatological practice, to observe if a lower concentration of the chemotherapic agent could be equally effective as the 25% formulation in improving the periodontal condition of nine patients with adult periodontitis. The results showed that this regimen can modify, at a statistically significant level, the clinical (Pocket Probing Depth, Gingival Bleeding Index and Plaque Index) and bacteriological (Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia and Veillonella parvula) parameters associated with adult periodontitis. The results are similar to those obtainable with a 25% Metronidazole-gel administered two times outdistanced by 7 days.

Microbiological and clinical effects of a 1% chlorhexidine-gel in untreated periodontal pockets from adult periodontitis patients.

The aim of this study was to report the microbiological and clinical effects of repeated subgingival administration of a 1% Chlorhexidine-gel in periodontal pockets from 10 patients with adult periodontitis. Results showed that the experimental treatment significantly improved clinical parameters (Plaque Index, Gingival Bleeding Index, and Pocket Probing Depth). Direct subgingival administration of Chlorhexidine-gel also produced a remarkable modification in the proportions of putative periodontopathic microorganisms, such as Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Veillonella parvula, Fusobacterium nucleatum, and Peptostreptococcus micros, in subgingival bacterial plaque from periodontitis patients.

[A comparative evaluation of the efficacy of the excisional new attachment procedure (ENAP) relative to root planing in the etiological phase of periodontal therapy]. / Valutazione comparativa dell'efficacia della excisional new attachment procedure (ENAP) nei confronti della levigatura radicolare nella fase etiologica della terapia parodontale.

BACKGROUND: In the present study, the effectiveness of root planing has been compared to the excisional new attachment procedure (ENAP) during the etiological phase of periodontal therapy, after the supragingival scaling, in order to establish if a technique offering an easy access to the subgingival areas could reduce the need for a surgical phase in the periodontal treatment. METHODS: Twenty-seven patients, affected by moderate periodontitis, participated in this study; in each of them root planing was performed in a half of the oral cavity (control site) and the ENAP in the other half (test site). The main clinical parameters of periodontal health (probing depth--PD-, attachment loss--AL-, plaque index--PlI- and gingival index--GI-) were evaluated before and 1, 2 and 6 months after the periodontal treatment. RESULTS: The results of the study showed that the parameters related with the amount of plaque and with the conditions of the marginal gingival tissue were not influenced by the different treatments used. Better improvements were found in PD and AL values in teeth treated by ENAP compared to those treated by root planing; this result is explained by a better access to the roots offered by the ENAP. CONCLUSIONS: We can conclude that, within the limits of the present study, the ENAP can reduce the need for a further surgical treatment of the periodontal patient.

Expanded polytetrafluoroethylene and dental rubber dam barrier membranes in the treatment of periodontal intrabony defects. A comparative clinical trial.

As observed in previous case reports, dental rubber dam (DRD) can be utilized as a barrier membrane in the guided tissue regeneration (GTR) technique for the treatment of periodontal intrabony defects. The purpose of the present study was (1) to confirm the validity of DRD as a suitable material in regenerative procedures and (2) to compare, in a split-mouth clinical trial, the effectiveness of DRD-made membranes in the treatment of periodontal intrabony defects versus that of expanded polytetrafluoroethylene (e-PTFE) barriers. 22 systemically healthy non-smoker adult periodontitis patients (7 male, 15 female) aged between 35 to 58 years were selected for the study. In each patient, a couple of 2-3 wall intrabony defects, located in different quadrants, were treated by a GTR technique using DRD (test sites) and e-PTFE (control sites), respectively. Performing a strict control of the oral hygiene level and of the marginal gingival health during the whole period of study, clinical (pocket probing depth, PPD; probing attachment level, PAL; gingival recession, GR) and intrasurgical (depth of the defect's intraosseous component, IOC; level of the alveolar crest, ACL) parameters were recorded at baseline and at the 1-year re-entry procedure in each experimental site. Furthermore, the coronal level of the newly formed tissue from the base of the defect (NFTL) and the vertical bone gain (VBG) were calculated at the time of membrane removal and after the re-entry procedure respectively. Membranes were removed from both test and control sites after 5 weeks; however, exposure of the membrane always occurred in test sites whereas it was observed in only 6 out of 22 control sites, this fact leading to an incomplete coverage of the regenerated tissue by the gingival flap in 18 out of 22 test sites. In both test and control sites, a statistically significant improvement of clinical and intrasurgical parameters occurred at the end of the study period; however, a significantly greater improvement was observed in control sites for PAL (+4.0 mm versus +3.0 mm; p<0.05) and VBG (3.9 mm versus 2.9 mm; p<0.05) although at the time of membrane removal, NFTL was similar between the experimental sites (test: 5.8; control: 5.6; p>0.05). Conversely, test sites exhibited a statistically significant greater increase in gingival recession (+1.9 versus +1.2; p<0.05) and alveolar crest resorption (-1.1 versus -0.3, p<0.01) in comparison to controls. It was concluded that (1) DRD is a suitable material to be used as a barrier membrane in GTR procedures although (2) e-PTFE membranes can provide a greater improvement in PAL and VBG, probably because of the difficulty in completely covering the regenerated tissue due to the fact that the gingival tissues have undergone a consistent recession in DRD-treated sites. Further studies are needed to demonstrate if an adequate coverage of the regenerated tissue in DRD-treated sites can eliminate these differences.

[Gingival hyperplasia in pregnancy. II. Etiopathogenic factors and mechanisms]. / Lesioni gengivali iperplastiche in gravidanza Nota II. Fattori e meccanismi eziopatogenetici.

The principal aspects of the hyperplastic pathology which frequently appears during pregnancy with a particular regard to the etiopathogenetic hypotheses are presented. The etiopathogenesis of the so-called pregnancy granuloma is rather complex, because in addition to the common irritant factors like bacterial plaque and calculus it is necessary to recognize the influence that hormonal modifications in pregnancy have on the predisposition to the development of gingival lesions. The hormonal influence acts by an intense inflammatory response and by a selective growth of some periodontal-pathogen and aggressive microbes, like Prevotella intermedia, whose increase in the subgingival plaque from the 3 degrees-4 degrees month of pregnancy coincide with the beginning of hyperplastic lesions. Sexual hormones seems to act as growth factors for the subgingival bacterial flora, in particular for Gram-negative anaerobic rods. The worsening of gingival conditions appears prevalently in the first quarter of pregnancy, in concomitance with the increase of urinary excretion of gonadotropins, that is in relation with an increased concentration of estrogens and progesteron in circulating blood. Sexual hormones could cause great modifications in peripheric vascular system, with a marked increase of vascular permeability and the following oedema of gingival tissues. In pregnancy the maternal immunological system presents some particular modifications, that allows to avoid the immunological rejection between mother and fetus, but reduce the reactivity of gingival tissues against local irritating factors.

[Hyperplastic gingival lesions in pregnancy. I. Epidemiology, pathology and clinical aspects]. / Lesioni gengivali iperplastiche in gravidanza. Nota I. Epidemiologia, patologia e clinica.

The principal aspects of the hyperplastic pathology which frequently appears during pregnancy and its epidemiological and clinical aspects are discussed. The existence of a particular kind of gingivitis, typical in pregnancy, not different from that appearing in not-pregnant women, let to hypothesize the existence of a relationship between the gingival lesion and the particular hormonal condition observed in pregnancy. Sometimes pregnancy gingivitis can show a tendency towards localized hyperplasia, this condition is defined pregnancy granuloma. Clinically a mass of variable size is observed; generally it appears in the 2 degrees-3 degrees month of pregnancy, with a tendency to bleeding and a possible interference with mastication. From a histological point of view, the pregnancy granuloma presents an inflammatory component characterized by lynphocytes, plasmacells and neutrophiles, an abundant vascular component with newly formed capillars and a great proliferation of fibroblasts. The differential diagnosis of pregnancy granuloma must be done with some forms of gingival hyperplasia, with pyogenic granuloma and with fibrous epulis (or hyperplasia). As to therapy, it is better to perform the surgical removal after delivery, considering that sometimes the lesions can spontaneously disappear. These lesions can reappear in a subsequent pregnancy.

[Periodontal guided tissue regeneration with a rubber dam: short term clinical study]. / Rigenerazione guidata dei tessuti parodontali con diga di gomma: studio clinico a breve termine.

BACKGROUND: The guided regeneration of periodontal tissues demonstrated to represent a therapeutical technique with predictable results. It has been observed that different materials, used as regenerative membranes, offer very similar results. Unconventional materials too, like the rubber dam, seem to be useful in the guided tissues regeneration technique. The object of the present study has been to comparatively evaluate the effectiveness of Gore-Tex and rubber dam-made membranes in the therapy of intra-osseous periodontal defects. MATERIALS AND METHODS: Six patients with two similar intra-osseous defects, participated in the study; one defect has been treated using, during the surgical intervention, a Gore-Tex membrane, while the other has received, a fragment of sterile rubber dam membranes. The principal clinical parameters of the periodontal health (probing depth -PD- and attachment loss -AL-) has been evaluated in both the defects before and 6 months after the periodontal surgery. RESULTS AND CONCLUSIONS: The results have showed that there are not statistically significant differences (p > 0.05) in the healing of the intra-osseous defects treated by rubber dam or Gore-Tex. The conclusion is drawn that the rubber dam can represent a valid and cheap alternative to the materials traditionally used in the regenerative surgery of the periodontal tissues.