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D N Tatakis

Publications and source records attributed to D N Tatakis.

At least 19 recordsLinked to original sources
PubMed2006

Oral clonidine pre-treatment and diazepam/meperidine sedation.

Clonidine has recently been used as a pre-operative medication and sedative/anxiolytic drug. Its extended duration of action makes it suitable for longer procedures. In this randomized, crossover, placebo-controlled clinical trial, we characterized the effects of oral clonidine pre-treatment on intravenous diazepam/meperidine sedation using the bi-spectral index (BIS) in 13 participants. Clonidine significantly increased the numbers of BIS-depressed readings and percent memory loss during sedation, while reducing total diazepam and post-operative analgesic dosages by 44% and 55%, respectively. Systolic, diastolic, and mean arterial blood pressures, as well as pulse rates, were reduced. Respiratory rate, oxygen saturation, end-tidal CO(2), and recovery from sedation were unchanged. Participants, surgeons, and sedationists preferred clonidine over the placebo. Clonidine pre-treatment increased and prolonged sedation and amnesia and stabilized vital signs while significantly decreasing diazepam and post-operative analgesic usage. These results suggest that pre-operative clonidine administration could be a useful supplement to intravenous sedation for dental procedures of long duration.

Administration, Oral↗
PubMed2005

Impaired cytotoxicity in Papillon-Lefèvre syndrome.

Papillon-Lefèvre syndrome (PLS), palmoplantar hyperkeratosis with periodontitis, has been genetically characterized. However, suspected associated immune dysfunctions remain elusive. The purpose of this study was to evaluate peripheral blood lymphocyte levels and natural killer (NK) cell cytotoxicity in PLS. Twenty patients and 20 healthy controls were examined. Peripheral blood lymphocytes were analyzed by flow cytometry for surface markers. NK cell cytotoxicity against K562 cells was determined by means of a 51Cr release assay. White blood cell differential and proportions of B-, T-, T-helper, T-suppressor, and NK cells revealed only sporadic borderline variations from control values. In contrast, NK cell cytotoxicity was consistently and severely depressed (32-53% of control values) in all patients. To the best of our knowledge, this newly described impairment of NK cell cytotoxic function is the first consistent immune dysfunction reported in PLS. This suggests that the impaired NK cell cytotoxicity might contribute to the pathogenesis of PLS-associated periodontitis.

Adolescent↗
PubMed2004

Modulation of clinical expression of plaque-induced gingivitis: effect of incisor crown form.

Evidence indicates that incisor crown form correlates with clinical periodontal features. It was hypothesized that incisor crown form may explain subject differences in gingivitis expression. The present experimental gingivitis study aimed to assess the effect of incisor crown form on plaque accumulation and gingival inflammation, and on individual susceptibility to plaque-induced gingivitis. Eighty-five periodontally healthy subjects were evaluated. A negative correlation was found between incisor crown width/crown length ratio and bleeding score (p = 0.045). From the 85 subjects, two groups of subjects with either 'long-narrow' or 'short-wide' incisor form were identified. The 'long-narrow' group had a significantly higher bleeding score than the 'short-wide' group (p = 0.014). No significant differences were found in the incisor crown width/crown length ratio between previously identified 'high responder' and 'low responder' subjects (Trombelli et al., 2004a). In conclusion, incisor crown form appears to affect the bleeding response of inflamed gingival tissues, while it exerts no influence on explaining differences in individuals' susceptibility to plaque-induced gingivitis.

Adult↗
PubMed2003

Periodontal diseases: current and future indications for local antimicrobial therapy.

The microbial etiology of gingivitis and periodontitis provides the rationale for use of adjunctive antimicrobial agents in the prevention and treatment of periodontal diseases. Although mechanical removal of supra- and subgingival calcified and non-calcified plaque deposits has been proved effective to control the gingival inflammatory lesions as well as to halt the progression of periodontal attachment loss, some patients may experience additional benefits from the use of systemic or topical antimicrobial agents. Such agents are able to significantly affect supra- and subgingival plaque accumulation and/or suppress or eradicate periodontal pathogenic microflora. Currently, properly selected local antiseptic and systemic antibiotic therapies can provide periodontal treatment that is generally effective, low-risk and affordable. This paper will briefly review the host-related conditions in which the periodontal preventive and therapeutic approaches may be effectively assisted by a local antimicrobial regimen. Potential future indications for adjunctive local antimicrobial therapy will also be discussed.

Anti-Infective Agents, Local↗
PubMed2003

Accelerated alveolar bone loss in mice lacking interleukin-10.

Interleukin-10 regulates pro-inflammatory cytokines, including those implicated in alveolar bone resorption. We hypothesized that lack of interleukin-10 leads to increased alveolar bone resorption. Male interleukin-10(-/-) mice, on 129/SvEv and C57BL/6J background, were compared with age-, sex-, and strain-matched interleukin-10(+/+) controls for alveolar bone loss. Immunoblotting was used for analysis of serum reactivity against bacteria associated with colitis and periodontitis. Interleukin-10(-/-) mice had significantly greater alveolar bone loss than interleukin-10(+/+) mice (p = 0.006). The 30-40% greater alveolar bone loss in interleukin-10(-/-) mice was evident in both strains, with C57BL/6J interleukin-10(-/-) mice exhibiting the most bone loss. Immunoblotting revealed distinct interleukin-10(-/-) serum reactivity against Bacteroides vulgatus, B. fragilis, Prevotella intermedia, and, to a lesser extent, against B. forsythus. The results of the present study suggest that lack of interleukin-10 leads to accelerated alveolar bone loss.

Alveolar Bone Loss↗
PubMed2001

Evidence of a founder effect for four cathepsin C gene mutations in Papillon-Lefèvre syndrome patients.

We describe a mutation and haplotype analysis of Papillon-Lefèvre syndrome probands that provides evidence of a founder effect for four separate cathepsin C mutations. A total of 25 different cathepsin C mutations have been reported in 32 families with Papillon-Lefèvre syndrome (PLS) and associated conditions. A characteristic of these findings is the diversity of different cathepsin C mutations that have been identified. To evaluate the generality of cathepsin C mutations, PLS probands representative of five reportedly unrelated Saudi Arabian families were evaluated by mutational and haplotype analyses. Sequence analysis identified two cathepsin C gene mutations: a novel exon 7 G300D mutation was found in the proband from one family, while probands from four families shared a common R272P mutation in exon 6. The R272P mutation has been previously reported in two other non-Saudi families. The presence of the R272P mutation in probands from these four Saudi families makes this the most frequently reported cathepsin C mutation. To distinguish between the presence of a possible founder effect or a mutational hot spot for the R272P mutation, we performed haplotype analysis using six novel DNA polymorphisms that span a 165 kb interval containing the cathepsin C gene. Results of haplotype analysis for genetic polymorphisms within and flanking the cathepsin C gene are consistent with inheritance of the R272P mutation "identical by descent" from a common ancestor in these four Saudi families. Haplotype analysis of multiple PLS probands homozygous for other cathepsin C mutations (W249X, Q286X, and T153I) also supports inheritance of each of these mutations from common ancestors. These data suggest that four of the more frequently reported cathepsin C mutations have been inherited from common ancestors and provide the first direct evidence for a founder effect for cathepsin C gene mutations in PLS. Identification of these six short tandem repeat polymorphisms that span the cathepsin C gene will permit haplotype analyses to determine other founder haplotypes of cathepsin C mutations in additional PLS families.

Amino Acid Substitution↗
PubMed2001

Intra- and inter-examiner reproducibility in keratinized tissue width assessment with 3 methods for mucogingival junction determination.

BACKGROUND: Although the need for "adequate" amount of keratinized tissue (KT) for periodontal health is questionable, the mucogingival junction (MGJ) often serves as a measurement landmark in periodontal evaluations. Limited information is available on the reproducibility of KT width (KTW) assessment. The purpose of this study was to assess intra- and inter-examiner reproducibility in measuring KTW by using 3 different methods to identify MGJ location. METHODS: Fifteen patients provided 17 teeth which had undergone a gingival augmentation procedure (connective tissue graft; surgery group) and an equal number of contralateral, non-treated teeth (control group). At the midbuccal aspect of each tooth, KTW was assessed by 2 independent examiners after MGJ identification by the visual (VM), functional (FM), and visual with histochemical staining (HM) method. Data analysis was based on intra-class correlation coefficients (ICC) and 3-way analysis of variance (ANOVA) for differences between replicate measurements. RESULTS: KTW was significantly different between treated and control teeth. No significant differences in KTW were found in relation to method for MGJ determination and examiner. Intra- and inter-examiner reproducibility was high, regardless of treatment status or method for MGJ determination (ICC = 0.92 - 0.99). Standard deviations of the difference between replicate measurements ranged from 0.46 mm for VM to 0.21 mm for HM. CONCLUSIONS: Intra- and inter-examiner reproducibility has been shown to be substantially consistent when different methods for MGJ determination are used to measure the apico-coronal dimension of the gingiva. The level of reproducibility does not seem to be affected whether or not the mucogingival complex has been surgically altered by a gingival augmentation procedure.

Adult↗
PubMed2000

Periodontal repair in dogs: effect of transforming growth factor-beta 1 on alveolar bone and cementum regeneration.

BACKGROUND: Transforming growth factor-beta (TGF-beta) represents a family of growth-modulating proteins with fundamental roles in connective tissue and bone development. The objective of this study was to evaluate the potential for regeneration of alveolar bone and cementum following surgical implantation of recombinant human TGF-beta 1 (rhTGF-beta 1). METHOD: Bilateral, critical size, supra-alveolar periodontal defects in 5 beagle dogs were surgically implanted with rhTGF-beta 1 in a calcium carbonate carrier (CaCO3) or with carrier alone. The animals were euthanized at 4 weeks postsurgery and block-biopsies of the defects were processed for histologic and histometric analysis. RESULTS: Surgical implantation of rhTGF-beta 1 resulted in minimal, if any, stimulation of alveolar bone or cementum regeneration. Linear bone and cementum regeneration in rhTGF-beta 1-treated defects was 1.2+/-0.6 and 0.01+0.01 mm, respectively. Corresponding values for the controls were 1.0+/-0.6 and 0.01+/-0.03 mm. CONCLUSIONS: The results suggest that, under the conditions (dose, carrier, defect type) evaluated here, treatment of periodontal defects in beagle dogs with rhTGF-beta 1 may be of limited clinical benefit.

Alveolar Process↗
PubMed2000

Gingival recession treatment: guided tissue regeneration with bioabsorbable membrane versus connective tissue graft.

BACKGROUND: Gingival recession represents a significant concern for patients and a therapeutic problem for clinicians. Several techniques have been proposed to achieve root coverage. The purpose of this randomized clinical trial was to evaluate the effect of a guided tissue regeneration (GTR) procedure in comparison to connective tissue graft (CTG) in the treatment of gingival recession defects. METHODS: Twelve patients, each contributing a pair of Miller Class I or II buccal gingival recessions, were treated. In each patient one randomly chosen defect received a poly(lactic acid)-based bioabsorbable membrane, while the paired defect received a CTG. Clinical recordings included oral hygiene standards and gingival health, recession depth (RD), recession width (RW), probing depth (PD), clinical attachment level (CAL), and keratinized tissue width (KT). RESULTS: Mean RD statistically significantly decreased from 2.5 mm presurgery to 0.5 mm with GTR (81% root coverage), and from 2.5 mm to 0.1 mm with CTG (96% root coverage), at 6 months postsurgery. Prevalence of complete root coverage was 58% for the GTR group and 83% for the CTG group. Mean CAL gain was 2.0 mm for the GTR group and 2.2 mm for the CTG group. No statistically significant differences between treatment groups were observed for changes in RD, RW, PD, CAL, and KT. CONCLUSIONS: Treatment of human gingival recession defects by means of either GTR or CTG results in clinically and statistically significant improvement of the soft tissue conditions of the defect when pre- and post-treatment measurements were compared. Although differences between CTG and GTR in mean root coverage and prevalence of complete coverage consistently favored the CTG procedure, the differences in measurements were not statistically significant.

Absorbable Implants↗
PubMed2000

Severe gingival recession in trisomy 18 primary dentition. A clinicopathologic case report of self-inflicted injury associated with mental retardation.

This clinicopathologic case report documents severe gingival recession in the primary dentition of a trisomy 18 patient. Primary molar and canine teeth exhibited recession extending beyond the midpoint of the buccal aspect of the root, occasionally reaching the root apex. Radiographic examination revealed taurodontism in both primary and permanent teeth. Clinical and histopathologic findings, along with case history, eliminated the possibility of prepubertal periodontitis and suggested a diagnosis of self-inflicted injury associated with mental retardation. Histologic examination of the primary teeth revealed normal cementum and dentin structure. Taurodontism, histologic structure of the dentition, and severe attachment loss in the primary dentition have not been described previously in trisomy 18.

Abnormalities, Multiple↗
PubMed2000

HLA-B27 transgenic rats are susceptible to accelerated alveolar bone loss.

BACKGROUND: HLA-B27 transgenic rats exhibit generalized, severe inflammatory reactions and spontaneously develop arthritis and chronic gastrointestinal inflammation, as well as inflammatory lesions in other tissues. Our hypothesis was that HLA-B27 rats would also be susceptible to inflammatory periodontal disease, and therefore alveolar bone loss. The purpose of this investigation was to compare the naturally occurring alveolar bone loss in HLA-B27 and wild type rats. METHODS: Age- and sex-matched HLA-B27 transgenic (TG) and wild type Fischer 344 (WT) female retired breeders, and their age-matched male WT breeding mates, were examined for alveolar bone loss (ABL). Thirty-eight animals were used: twelve, 20, and 6 animals were 6, 8, and 12 months old, respectively. ABL was measured as the exposed root surface area (mm2) in the defleshed maxilla and mandible. RESULTS: The coefficient of variation for replicate ABL measurements was 4.4%. For the 6- and 8-month age groups, ABL was significantly greater in TG rats compared to WT rats. The observed difference in ABL between TG and WT animals did not reach statistical significance for the 12-month age group. Within each of the two animal groups (TG and WT), ABL was significantly different between age groups. The ABL rate of TG female rats was 42% to 250% greater than that of WT female rats, depending on the age range examined. CONCLUSIONS: HLA-B27 rats are susceptible to accelerated alveolar bone loss and could serve as an animal model of alveolar bone loss pathogenesis.

Alveolar Bone Loss↗
PubMed1999

Adverse effects associated with a bioabsorbable guided tissue regeneration device in the treatment of human gingival recession defects. A clinicopathologic case report.

This clinicopathologic case report documents an adverse effect associated with the use of a polylactic acid-based barrier in the treatment of human gingival recession defects. A total of 27 consecutively treated patients, in whom guided tissue regeneration with a polylactic acid barrier was used to correct gingival recession defects, were evaluated. This adverse effect consisted of a midradicular-apical swelling, generally asymptomatic, with no apparent predilection for gender, age, tooth type or location (maxilla/mandible), or surgical procedure. It was observed in 14 of 27 (52%) patients and 22 of 41 (54%) defects. The swelling decreased in size over time and in most cases, it completely resolved within 12 months postsurgery. Histopathologic evaluation of a 14-week specimen indicated characteristics (multinucleated giant cells, foamy macrophages) consistent with a foreign body reaction. These findings suggest that patients undergoing GTR procedures with synthetic absorbable devices for the treatment of gingival recession defects should be advised of the possible occurrence of such an adverse effect.

Absorbable Implants↗
PubMed1998

Resorbable barrier and envelope flap surgery in the treatment of human gingival recession defects. Case reports.

The present case report evaluates the treatment outcome following mucogingival surgery combined with a bioresorbable barrier in gingival recession defects in humans. A total of 11 buccal, Miller Class I or II, gingival recession defects in 6 patients were consecutively treated. The exposed root surface was ultrasonically scaled and conditioned with a tetracycline HCl solution (10 mg/ml) for 4 min. A buccal full/split thickness envelope flap was then elevated, and a bioresorbable matrix barrier was positioned to completely cover the exposed root surface and surrounding bone margins. A flap was then positioned at or slightly coronal to its original position. In all cases, a variable amount of membrane was intentionally left uncovered on the exposed root surface. Clinical recordings, assessed presurgery and at 6 months postsurgery, included defects-specific plaque and gingival scores, recession depth (RD), probing depth (PD), clinical attachment level (CAL) and keratinized tissue width (KT). Immediately postsurgery, and at weeks 1, 2, 4, 6 and 8 postsurgery, the location of gingival margin or granulation tissue covering the previously exposed root surface was recorded, as well as the extent of barrier exposure. Statistical analysis showed that RD decreased from 2.3+/-0.2 mm presurgery to 0.8+/-0.5 mm at 6 months postsurgery (p=0.001), representing a mean root coverage of 65% (range: 40-100%). CAL gain paralleled RD reduction (1.5+/-0.5 mm; p=0.0009), while KT showed a slight increase (0.3+/-0.6 mm) at 6 months postsurgery. Results indicate that clinical improvement of gingival recession defects may be achieved by means of a barrier-supported envelope technique. The bioresorbable matrix barrier represented an effective scaffold to support the reconstruction of the mucogingival unit.

Adult↗
PubMed1998

Periodontal repair in dogs: effect of recombinant human transforming growth factor-beta1 on guided tissue regeneration.

This study evaluated alveolar bone and cementum regeneration following surgical implantation of recombinant human transforming growth factor-beta1 (rhTGF-beta1) in conjunction with guided tissue regeneration (GTR). Supraalveolar, critical size, periodontal defects were surgically created around the 3rd and 4th mandibular premolar teeth in right and left jaw quadrants in 5 beagle dogs. Alternate jaw quadrants in consecutive animals received rhTGF-beta1, in a CaCO3/hydroxyethyl starch carrier with GTR, or carrier with GTR alone (control). 20 microg of rhTGF-beta1 in buffer solution was incorporated into approximately 0.8 ml of carrier for each defect scheduled to receive rhTGF-beta1. Animals were sacrificed at week 4 postsurgery and tissue blocks were harvested and processed for histometric analysis. Clinical healing was generally uneventful. Minor membrane exposures were observed. Defects with membrane exposure displayed an inflammatory infiltrate underneath the membrane. Bone regeneration of trabecular nature, apparent in all animals, was generally limited to the very apical aspect of the defects. Cementum regeneration was limited without obvious differences between experimental conditions. Comparing rhTGF-beta1, to control defects, statistically significant differences were found for area (1.8+/-0.4 and 1.3+/-0.6 mm2, respectively; p<0.05) and density (0.3+/-0.1 and 0.2+/-0.03, respectively; p<0.05) of alveolar bone regeneration. Observed differences are small and represent a clinically insignificant potential for enhanced regeneration in this preclinical model. Within the limitations of study, it may be concluded that rhTGF-beta1 has a restricted potential to enhance alveolar bone regeneration in conjunction with GTR.

Alveolar Bone Loss↗
PubMed1998

Subpedicle connective tissue graft versus guided tissue regeneration with bioabsorbable membrane in the treatment of human gingival recession defects.

The purpose of the present clinical study was to evaluate the effect of guided tissue regeneration (GTR) in comparison to subpedicle connective tissue graft (SCTG) in the treatment of gingival recession defects. A total of 12 patients, each contributing a pair of Miller's Class I or II buccal gingival recessions, was treated. According to a randomization list, one defect in each patient received a polyglycolide/lactide bioabsorbable membrane, while the paired defect received a SCTG. Treatment effect was evaluated 6 months postsurgery. Clinical recordings included full-mouth and defect-specific oral hygiene standards and gingival health, recession depth (RD), recession width (RW), probing depth (PD), clinical attachment level (CAL), and keratinized tissue width (KT). Mean RD significantly decreased from 3.1 mm presurgery to 1.5 mm at 6 months postsurgery for the GTR group (48% root coverage), and from 3.0 mm to 0.5 mm for the SCTG group (81% root coverage). RD reduction and root coverage were significantly greater in SCTG group compared to GTR group. Mean CAL gain amounted to 1.7 mm for the GTR group, and 2.3 mm in the SCTG group. No significant differences in PD changes were observed within and between groups. KT increased significantly from presurgery for both treatment groups, however gingival augmentation was significantly greater in the SCTG group compared to GTR group. Results indicate that: 1) treatment of human gingival recession defects by means of both GTR and SCTG procedures results in clinically and statistically significant improvement of the soft tissue conditions of the defect; and 2) treatment outcome was significantly better following SCTG compared to GTR in terms of recession depth reduction, root coverage, and keratinized tissue increase.

Absorbable Implants↗
PubMed1998

Infrared microspectroscopic imaging of biomineralized tissues using a mercury-cadmium-telluride focal-plane array detector.

A 64 x 64 mercury-cadmium-telluride focal-plane array detector attached to a Fourier transform infrared microscope was used to spectroscopically image 5 microm sections of canine alveolar bone tissue in the fingerprint region of the infrared spectrum. By ratioing the relative intensities of specific bands across the images, it is possible to obtain spatial distributions of the mineral-to-matrix ratio and mineral maturity as a function of distance from an osteon.

Animals↗
PubMed1997

Bone morphogenetic protein-2 for peri-implant bone regeneration and osseointegration.

Recombinant human bone morphogenetic protein-2 (rhBMP-2) induced bone regeneration and osseointegration was evaluated in supraalveolar peri-implant defects in 5 beagle dogs. Alveolar bone was reduced 5 mm in height in mandibular premolar areas and the premolars were extracted. Three 10 mm titanium fixtures were placed 5 mm into each reduced alveolar crest, leaving 5 mm in a supraalveolar position. Alternate quadrants in consecutive animals received a surgical implant consisting of 2 ml rhBMP-2 (0.43 mg/ml) in a type I bovine collagen carrier, or the carrier alone (control). Fixtures and surgical implants were submerged under the gingival flaps. The healing interval was 16 weeks. Histometric and radiographic evaluations were made. Defect height averaged (+/- SD) 5.3 +/- 0.2 and 5.1 +/- 0.2 mm for rhBMP-2 and control defects, respectively (P > 0.05, n = 5, paired, t-test) Bone regeneration (height) averaged 4.2 +/- 1.0 and 0.5 +/- 0.3 mm for rhBMP-2 and control defects, respectively (P < 0.05). Bone regeneration (area) averaged 6.1 +/- 6.3 and 0.2 +/- 0.2 mm2 for rhBMP-2 and control defects, respectively (P > 0.05). Osseointegration within the confines of the defect averaged 19.1 +/- 10.1% and 8.2 +/- 4.6% for rhBMP-2 and control defects, respectively (P > 0.05). Osseointegration within regenerated bone averaged 29.1 +/- 9.8% and 65.3 +/- 15.3% for rhBMP-2 and control defects, respectively (P < 0.05). Osseointegration within the retained alveolar bone averaged 67.1 +/- 4.6% and 68.1 +/- 3.6% for rhBMP-2 and control defects, respectively (P > 0.05). The results suggest that there is a potential for rhBMP-2 induced bone regeneration and osseointegration in surgical peri-implant defects.

Alveolar Process↗