Comparison of simulated periodontal bone defect depth measured in digital radiographs in dedicated and non-dedicated software systems

Objectives: To compare simulated periodontal bone defect depth measured in digital radiographs with dedicated and non-dedicated software systems and to compare the depth measurements from each program with the measurements in dry mandibles.Methods: Forty periodontal bone defects were created at the proximal area of the first premolar in dry pig mandibles. Measurements of the defects were performed with a periodontal probe in the dry mandible. Periapical digital radiographs of the defects were recorded using the Schick sensor in a standardized exposure setting. All images were read using a Schick dedicated software system (CDR DICOM for Windows v.3.5), and three commonly available non-dedicated software systems (Vix Win 2000 v.1.2; Adobe Photoshop 7.0 and Image Tool 3.0). The defects were measured three times in each image and a consensus was reached among three examiners using the four software systems. The difference between the radiographic measurements was analysed using analysis of variance (ANOVA) and by comparing the measurements from each software system with the dry mandibles measurements using Student's t-test.Results: the mean values of the bone defects measured in the radiographs were 5.07 rum, 5.06 rum, 5.01 mm and 5.11 mm for CDR Digital Image and Communication in Medicine (DICOM) for Windows, Vix Win, Adobe Photoshop, and Image Tool, respectively, and 6.67 mm for the dry mandible. The means of the measurements performed in the four software systems were not significantly different, ANOVA (P = 0.958). A significant underestimation of defect depth was obtained when we compared the mean depths from each software system with the dry mandible measurements (t-test; P congruent to 0.000).Conclusions: the periodontal bone defect measurements in dedicated and in three non-dedicated software systems were not significantly different, but they all underestimated the measurements when compared with the measurements obtained in the dry mandibles.

Anatomy of the frontal gland and ultramorphology of the frontal tube in the soldier caste of species of Nasutitermitinae (Isoptera, Termitidae)

is a predominant characteristic, conditioned by the presence of castes with different morphology, ontogeny, and development. The soldier caste is unique among social insects and it is responsible for colony defense. Soldiers belonging to the Nasutitermitinae subfamily are very peculiar, since they may be polymorphic and present a nasus in addition to either developed or vestigial mandibles. The defensive secretions of soldiers of the neotropical Nasutitermitinae have been the aim of several chemical studies, but few data exist concerning the anatomy and histology of the exocrine glands. This article presents a comparative study on the anatomy of the frontal gland of soldiers of several Nasutitermitinae species: Syntermes dirus (Burmeister), Syntermes nanus (Constantino), Constrictotermes cyphergaster (Silvestri), Nasutitermes corniger (Motschulsky) and Velocitermes heteropterus (Silvestri), with emphasis on the ultramorphology and ultrastructure of the frontal tube.

Histological evaluation of the response of apical tissues to glass ionomer and zinc oxide eugenol based sealers in dog teeth after root canal treatment

The object of the study was to compare two commercial root canal sealers: Ketac-Endo (a glass ionomer cement) and Fill Canal (a zinc oxide-eugenol cement). A total of 34 root canals from dog premolars with vital pulps were used. After instrumentation, the root canals were sealed with Ketac-Endo and Fill Canal cements using gutta-percha and a lateral condensation technique. After 270 days the animals were sacrificed with an anesthetic overdose and the maxillae and mandibles were removed and fixed in formalin for 48 h. After routine histological processing the sections were stained with hematoxylin-eosin and Mallory trichrome stains. Microscopic analysis revealed that Ketac-Endo cement presented better results than Fill Canal cement.

FRONTAL GLAND DEHISCENCE IN THE BRAZILIAN TERMITE SERRITERMES-SERRIFER (ISOPTERA, SERRITERMITIDAE)

The primary function of the soldier caste in the Isoptera is the defense of the termite society. The simplest defense is mechanical with oversized mandibles. Besides the mandibles, some termite soldiers use exocrine glands as a means of chemical defense. These glands produce substances which are toxic and/or repellent to termites enemies. Here we report the only case in the Neotropical fauna of dehiscence of the frontal gland in the soldier caste of the Brazilian termite, Serritermes serrifer (Bates).

Effect of calcitonin on bone regeneration in male rats: a histomorphometric analysis

The aim of this study was to evaluate the effectiveness of calcitonin in promoting bone growth in surgical bone defects in rat mandibles. Fifty male rats were divided into two groups: bone defect (control) and bone defect with calcitonin (experimental). A circular bone defect 4 mm in diameter was made in the mandibular bone of the rats in the angle region, and covered with a polytetrafluoroethylene barrier. The experimental group received 2 IU/kg of synthetic salmon calcitonin intramuscularly three times a week, with treatment starting immediately after surgery. The animals were killed 3, 7, 14, 21 and 28 days after the surgical procedure. The bone defects were examined histologically and by histomorphometric analysis. The Student t-test was applied to the histomorphometric data, with the level of significance set at 5%. The animals of the experimental group showed a lower level of bone formation at almost all time points than the control group, but no difference between groups was observed 28 days after surgery. The volume of newly formed bone matrix was significantly greater in the control than the experimental group at 7, 14 and 21 days, as determined by both morphologic and histomorphometric analysis. Bone repair in the calcitonin-treated animals was delayed in comparison to controls, indicating the need for further studies on male rats.

Hard tissue formation adjacent to implants of various size and configuration immediately placed into extraction sockets: an experimental study in dogs

ObjectivesTo evaluate the influence of implant size and configuration on osseointegration in implants immediately placed into extraction sockets.Material and methodsImplants were installed immediately into extraction sockets in the mandibles of six Labrador dogs. In the control sites, cylindrical transmucosal implants (3.3 mm diameter) were installed, while in the test sites, larger and conical (root formed, 5 mm diameter) implants were installed. After 4 months of healing, the resorptive patterns of the alveolar crest were evaluated histomorphometrically.ResultsWith one exception, all implants were integrated in mineralized bone, mainly composed of mature lamellar bone. The alveolar crest underwent resorption at the control as well as at the test implants. This resorption was more pronounced at the buccal aspects and significantly greater at the test (2.7 +/- 0.4 mm) than at the control implants (1.5 +/- 0.6 mm). However, the control implants were associated with residual defects that were deeper at the lingual than at the buccal aspects, while these defects were virtually absent at test implants.ConclusionsThe installment of root formed wide implants immediately into extraction sockets will not prevent the resorption of the alveolar crest. In contrast, this resorption is more marked both at the buccal and lingual aspects of root formed wide than at standard cylindrical implants.To cite this article:Caneva M, Salata LA, de Souza SS, Bressan E, Botticelli D, Lang NP. Hard tissue formation adjacent to implants of various size and configuration immediately placed into extraction sockets: an experimental study in dogs.Clin. Oral Impl. Res. 21, 2010; 885-895.doi: 10.1111/j.1600-0501.2010.01931.x.

ANALISE MORFOLOGICA DE 'SPINA MENTALIS' DE MANDIBULAS HUMANAS ADULTAS DE BRASILEIROS BRANCOS E NEGROS

This study was carried out to verify the morphology of the spina mentalis. We observed 275 human adult mandibles of both sexes and ethnic groups. An analysis of the results allows the following conclusions. The spina mentalis exists in 90.04% ±1.8 of the mandibles of Whites and Negroes. The typical form with four tubercles, as described by some authors, is rarely found. In most cases it is characterized by the presence of: two upper tubercles (27.27%±7.2), two superior tubercles and one inferior (24.72%±6.7), and one elongated median tubercle (24.0%±6.6); The forms and volumes of the tubercles are very irregular and seem not to depend on age, sex or ethnic group. The spina was absent in 9.8%±3.2 of the cases, especially in mandibles of White teethless individuals. An hypertrophic spina mentalis, generally formed at the expense of the upper tubercle, was observed in only 1.45%±0.5 of the cases.

A new species of Constrictotermes from central Brazil with notes on the mandibular glands of workers (Isoptera: Termitidae: Nasutitermitinae)

Constrictotermes rupestris, new species, is described from central Brazil, with illustrations of the imago, soldier, worker head, worker mandibles, worker mandibular gland, and nest. The new species lives in a dry forest, on rocky terrain, building its nest always on rocks. In the colonies examined, all castes showed a striking reddish coloration due to something accumulated in the fat tissues. Inquilinitermes microcerus was present in most examined nests. The worker of C. rupestris has an enlarged mandibular gland. Workers also show an aggressive behavior, which suggests that the mandibular glands may produce defensive secretions.

Behavior of Atta sexdens rubropilosa (Hymenoptera: Formicidae) workers during the preparation of the leaf substrate for symbiont fungus culture

The behavioral repertory of Atta sexdens rubropilosa Forel (Hymenoptera: Formicidae) workers marked by size category was studied during the preparation of the leaf substrate in the laboratory. The workers were marked according to three physical castes, i.e., minima, generalist and forager. Seven types of behavioral acts were recorded for each caste, with the following frequencies: licking leaf fragments (64.6%), holding fragments on the surface of the fungus garden (16.4%), shredding the fragments (6.0%), chewing and crimping the edges of the fragments (9.0%), incorporating the fragments (2.7%), touching the surface of the fungus with their mandibles and other mouthparts after incorporation (0.3%), and depositing fecal fluid (0.1%). The minima workers were found to be more specialized in the activities related to the preparation of the leaf substrate, which represented 52% of the total number of tasks performed. The generalists performed 40.3% of these tasks, and the foragers 7.9%. Licking the substrate was the behavior most frequently recorded and performed for a longer period of time. In this way, the workers may feed and at the same time eliminate microorganisms that are harmful to the symbiont fungus. The smaller castes, minima and generalists, are those most responsible for the preparation of the leaf substrate and predominate within a colony. From a practical viewpoint, with the introduction of toxic bait containing insecticides, for example, these size categories will be those most intensely intoxicated, especially through the behavior of licking bait pellets. On the basis of the data obtained about these behaviors, we may raise the hypothesis that trophallaxis in not the major factor triggering contamination with an insecticide among the workers of a colony.

Ultramorphology and histology of the ectal mandibular gland in Polistes versicolor (Olivier) (Hymenoptera: Vespidae)

The ectal mandibular gland (EMG) of wasps is homologous to the mandibular gland of ants and bees. This gland belongs to salivary system and its function stile unknown. The EMG of Polistes versicolor showed histological and ultramorphological features similar to that founded in ants and others wasps. This gland is constituted by a secretory region and a reservoir. The secretory region contains individual secretory cells that showed several nucleoli. The reservoir has a club shape and is connected to each mandible, by a duct that opens on its external side, which there are cuticular projections. The EMG of males is smaller than those of females. Our results suggested that the EMG secrete volatiles compounds that are liberated when the mandibles still open.

Microbiologic and radiographic analysis of ligature-induced peri-implantitis with different dental implant surfaces

Purpose: The goal of this study was to evaluate microbiota and radiographic peri-implant bone loss associated with ligature-induced peri-implantitis. Materials and Methods: Thirty-six dental implants with 4 different surfaces (9 commercially pure titanium, 9 titanium plasma-sprayed, 9 hydroxyapatite, and 9 acid-etched) were placed in the edentulous mandibles of 6 dogs. After 3 months with optimal plaque control, abutment connection was performed. On days 0, 20, 40, and 60 after placement of cotton ligatures, both microbiologic samples and periapical radiographs were obtained. The presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia/nigrescens, Campylobacter spp, Capnocytophaga spp, Fusobacterium spp, beta-hemolytic Streptococcus, and Candida spp were evaluated culturally. Results: P intermedia/nigrescens was detected in 13.89% of implants at baseline and 100% of implants at other periods. P gingivalis was not detected at baseline, but after 20 and 40 days it was detected in 33.34% of implants and at 60 days it was detected in 29.03% of dental implants. Fusobacterium spp was detected in all periods. Streptococci were detected in 16.67% of implants at baseline and in 83.34%, 72.22%, and 77.42% of implants at 20, 40, and 60 days, respectively. Campylobacter spp and Candida spp were detected in low proportions. The total viable count analysis showed no significant differences among surfaces (P = .831), although a significant difference was observed after ligature placement (P < .0014). However, there was no significant qualitative difference, in spite of the difference among the periods. The peri-implant bone loss was not significantly different between all the dental implant surfaces (P = .908). Discussion and Conclusions: These data suggest that with ligature-induced peri-implantitis, both time and periodontal pathogens affect all surfaces equally after 60 days.

Histochemistry and protein profile of the mandibular glands of workers of the ant Atta sexdens rubropilosa (Hymenoptera: Formicidae)

Insect mandibular glands are always associated to the mandibles; they are part of the salivary glandular system. The mandibular glands are composed by a reservoir associated to the secretory cells, with each secretory cell connected to the reservoir by means of individual canaliculi. These glands play an important role in the production of pheromones, which are compounds involved in defense, communication, and reproduction of the colony. Mandibular glands of soldiers and major and minor workers of the ant Atta sexdens rubropilosa were processed for different histochemical tests, total protein content, and protein electrophoretic profile determination. The histochemical tests detected the presence of lipids, DNA/RNA, polysaccharides, and proteins at different regions of the gland. The protein electrophoretic profiles showed that the total protein content as well as the number of peptides of each caste follow a progressive order in relation to the size of the individual. Thus, we suggest that the production of secretion is directly linked to the task that the individual performs in the colony.

A new device in immediately loaded implant treatment in the edentulous mandible

Purpose: This article reports preliminary clinical results of the Speed Master system, a method for immediate loading of implants for the treatment of mandibular edentulism. Materials and Methods: Fifteen patients with edentulous mandibles were consecutively included in the study. Each received 4 implants between the mental foramina placed using the system's surgical guides. Permanent fixed prostheses fabricated over premanufactured titanium bars were attached to the implants on the day of implant placement. The patients were followed for 15 to 27 months (mean, 19 months). Peri-implant tissues were periodically evaluated. Marginal bone loss was monitored with periapical radiographs using a computerized technique. Satisfaction was assessed by means of a questionnaire. Results: The overall implant and prosthetic survival rates were 100%. At the time of the final follow-up visit, mean marginal bone loss was 1.11 mm, and bleeding on probing was not observed. Only 6.7% of the patients reported any discomfort during treatment, and all patients would recommend the procedure to others. Discussion: The immediate loading of implants placed in the edentulous mandible with the Speed Master surgical and prosthetic protocol reduces treatment time and number of surgical procedures in comparison to classic delayed loading protocols. Conclusion: The rehabilitation of the mandible with an immediately delivered occlusally loaded hybrid prosthesis supported by 4 implants does not appear to jeopardize the success of the osseointegration and represents a viable treatment option.

On the morphology of the juvenile stages of Ampulex compressa (Fabricius 1781) (Hymenoptera, Ampulicidae)

Ampulex compressa is a cockroach-hunting ampulicid wasp. In this survey we describe its egg, mature larva, along with the 1st and 2nd larval instars and cocoon, with emphasis on the characters considered important to the phylogeny of apoid wasps. It shares the following traits with the Sphecidae: reduced head setae, absence of antennal papilla, three antennal sensilla on antennal orbit, broad and strongly emarginate labrum, and spinneret with prominent raised lips. In common with other Ampulicidae, it has integument of the body granulose and without setae, mandibles with four or five teeth and lacking basal setae, maxillary palp larger than galea and discrete parietal bands. Distinct from the other Ampulicidae, it has a deep median longitudinal groove in the area above the salivary lips, a distinct group of five sensilla on the subgenal area, and lacks spines on the spiracular peritreme. Copyright © 2006 Magnolia Press.

The effect of alcohol consumption on periodontal bone support in experimental periodontitis in rats

Objective: The aim of this study was to evaluate the effect of the alcohol consumption on the periodontal bone support (PBS) in experimental periodontitis in rats. Materials and Methods: Sixty-three male rats were divided into seven groups: G1 (control); G2 (10% ethanol); G3 (nutritional control of G2); G4 (20% ethanol); G5 (nutritional control of G4); G6 (30% ethanol) and G7 (nutritional control of G6). The groups G3, G5 and G7 received controlled diets with equivalent caloric amounts to those consumed in G2, G4 and G6 respectively, with the ethanol replaced by sucrose. After anesthesia, ligatures were installed around the mandibular first molar, leaving the contralateral teeth unligated. After 8 weeks, the rats were killed and their mandibles were radiographed to measure the percentage of PBS on the distal aspect. Results: The intragroup analyses showed that presence of ligatures induced periodontitis (p<0.05). Unligated groups did not show significant differences among the percentages of PBS (p=0.1969). However, in ligated groups the rats that received alcohol (G2:48.71%±3.88; G4:47.66%±2.54; G6:47.32%±3.24) and the nutritional control group associated with a high concentration of ethanol (G7:47.40%±3.24) presented a significantly lower percentage of PBS than the other groups (G1:52.40%±2.75; G3:52.83%±2.41; G5:50.85%±4.14). Conclusions: These results demonstrated that alcohol consumption in rats may result in a direct effect on alveolar bone loss and increased development of periodontitis. In addition, they suggest that heavy caloric consumption of ethanol may also present an indirect effect on periodontal tissue as a consequence of malnutrition.