Lingual Position of the Wrought Wire Clasp for Removable Partial Dentures Esthetic

BackgroundThe esthetic repair of a removable partial appliance is a critical function that determines the success of the therapy. The most challenging challenge is to achieve While maintaining stability, retention, and protect teeth's health, optimal esthetics is achieved. Removable partial prosthesis is an odious therapeutic option that we still have to use in some circumstances and is a common procedure. However, these patients anticipate receiving a prosthesis. ObjectiveTo determine wrought wire clasp for removable partial dentures for esthetic. Materials and MethodsAfter taking impressions (primary and final) for the maxilla or the mandible of many patients, stone castings were pouring in class III (dental stone) using a 30 ml water to 100 g powder ratio. For the installation of prosthetic teeth, a uniform denture base plate wax template was made on each stone cast, and lingual clasps were inserted around the abutment teeth. Dental plaster is used to flake the lower piece of the traditional brass flasks (class II). The denture foundation was meticulously deflasked, after the curing cycle, the surplus is removed and the denture surface is polished. ResultsDentures that have been treated using this method have a high level of retention. Excellent aesthetics, make it more sanitary and dentures with the lingual clasps method are more comfortable for the patient. ConclusionDentures made with this procedure have better retention, a better esthetic, are good hygienic, and are high comfortable for the patient than dentures made using labial clasps.

Presence and Maturation Dynamics of Mandibular Third Molars and Their Influence on Late Mandibular Incisor Crowding: A Longitudinal Study

The objective of this study was to investigate the relationship between the absence, presence and dynamics of mandibular third molar development and the occurrence and amount of late mandibular incisor crowding. Dental plaster casts and panoramic radiographs of 72 orthodontically untreated subjects from the Nittedal growth study, Norway were analyzed. The subjects were recalled for a checkup at 12, 15, 18 and 21 years of age. Mandibular incisor crowding was assessed using Little’s irregularity index and dental maturation of the third molars by the Cameriere’s index. The majority of the subjects (64%) had ≥1 mm increase in irregularity; 22% experienced an increase of 0.1–0.9 mm and 14% had unchanged or decreased irregularity. Incisor irregularity increased with age, regardless of absence or presence of third molars. The amount of change in incisor irregularity from 12 to 21 years did not differ significantly between subjects with hypodontia of third molars, extraction and those with third molars present. No differences were observed between erupted, unerupted or impacted third molars. No correlation was found between the amount of change in irregularity and maturation of the third molars. In conclusion, occurrence and amount of mandibular late incisor crowding is not significantly influenced by the presence of mandibular third molars or their development dynamics.

Presence and Maturation Dynamics of Mandibular Third Molars and Their Influence on Late Mandibular Incisor Crowding: Longitudinal Study

OBJECTIVE: To investigate the relationship between the presence and dynamics of mandibular third molar development and the occurrence and amount of late mandibular incisor crowding. MATERIALS AND METHODS: Dental plaster casts and panoramic radiographs of 72 orthodontically untreated subjects from the Nittedal growth study, Norway were analysed. The subjects were recalled for check-up at 12, 15, 18 and 21 years of age. Mandibular incisor crowding was assessed using the Little’s irregularity index and dental maturation of the third molars by the Cameriere’s index.RESULTS: The majority of the subjects (64%) had ≥1mm increase in irregularity; 22% experienced increase of 0.1-0.9mm and 14% had unchanged or decreased irregularity. Incisor irregularity increased with age, regardless of absence or presence of third molars. The amount of change in incisor irregularity from 12 to 21 years did not differ significantly between subjects with hypodontia of third molars, extraction and those with third molars present. No differences were observed between erupted, unerupted or impacted third molars. No correlation was found between the amount of change in irregularity and maturation of the third molars.CONCLUSIONS: Occurrence and amount of mandibular late incisor crowding is not significantly influenced by presence or development dynamics of mandibular third molars.

Setting time of construction gypsum, dental plaster, and white orthodontic gypsum

Background. Dental plaster, white orthodontic gypsum, and construction gypsum have β-hemihydrate particles. Setting time is an essential property of dental gypsum, which can affect the strength of the material. This research aimed to compare construction gypsum, dental plaster, and white orthodontic gypsum’s initial and final setting times. Methods. Three groups were included in this experimental laboratory study: construction gypsum (A), dental plaster (B), and white orthodontic gypsum (C). Each group consisted of 10 samples. Gypsum manipulation consisted of using 120 gr of powder and 60 mL of water. Gypsum powder and water were mixed using a gypsum mixer at 120 rpm. A homogeneous mixture was poured into a mold, and the setting time was measured using a Gillmore needle, according to ASTM C266-03. The initial setting time test was measured using 113.4 grams and a 2.12-mm needle. The final setting time was measured using 453.6 grams and a 1.06-mm needle. This test was repeated until the needle failed to penetrate the gypsum’s surface. All the data were analyzed with one-way ANOVA and post hoc Tukey tests using SPSS 23. Results. The average initial setting time for groups A, B, and C were 10.39±1.19, 16.17±1.40, and 24.46±1.51, respectively. The average final setting time for groups A, B, and C were 15.97±0.79, 24.31±0.88) and 33.37±0.66, respectively. One-way ANOVA and post hoc Tukey tests showed significant differences in the initial and final setting times between the three groups (P<0.05). Conclusion. There were differences in setting time between dental plaster, white orthodontic gypsum, and construction gypsum. The construction gypsum’s setting time is suitable as a type II dental gypsum, according to ADA No.25.

Wolf spider burrows from a modern saline sandflat in central Argentina: morphology, taphonomy and clues for recognition of fossil examples

Pavocosasp. (Lycosidae) burrows found in an open sparsely vegetated area on the edge of the Gran Salitral saline lake, in central Argentina, are described. Burrows were studied by capturing the occupant and casting them with dental plaster. The hosting sediments and vegetation were also characterized. InhabitedPavocosasp. burrows display distinctive features as open, cylindrical, nearly vertical, silk lined shafts about 120 mm long, subcircular entrances, a gradual downward widening, and a particularly distinctive surface ornamentation in the form of sets of two linear parallel marks at a high angle to the burrow axis. Instead, casts of vacatedPavocosasp.burrows showed some disturbances caused either by the reoccupation by another organism or by predation of the dweller. Two morphologies are related to reoccupation of burrows: those with a structure in form of an “umbrella” and another with smaller excavations at the bottom of the burrow. Predation by small mammals produces funnel-shaped burrows. Both active and abandonedPavocosasp. burrow casts are compared with existing ichnogenera and inorganic sedimentary structures, highlighting its distinction. It is argued that key features like the presence of a neck, a downward widening and the described surface texture will allow recognition of wolf spider burrows in the fossil record. However, the putative spider burrows described in the literature either lack the necessary preservational quality or do not show ornamentation similar to the modern wolf spider burrows. Fossil wolf spiders are recorded since the Paleogene (possibly Late Cretaceous), therefore Cenozoic continental rocks can contain wolf spider burrows awaiting recognition. In addition, the particular distribution ofPavocosasp. in saline lakes may imply that this type of burrow is linked to saline environments.

Correlation between Von Spee’s Curve and Vertical Dental Eruptions in Class II Division-2 Malocclusion

Introduction: Von Spee’s curve is one of the important treatment aspects in orthodontics. Any orthodontic treatment planning is dependent on this key factor.Objective: To find out the correlation between the Von Spee’s curve and occlusal eruption of anterio-posterior teeth in Class II Division 2 malocclusion.Materials & Method: Current research was conceived at the Department of Orthodontics, de’Montmorency College of Dentistry and Faisalabad Medical University. Two hundred and fifty Class II Division 2 patients (112 male, mean age: 15.1±1.5 years; 138 female, mean age: 15.4± 1.3 years) were included. Depth of the curve was calculated on lateral cephalograms and dental plaster models, and correlated with the vertical eruption of lower incisal teeth and posterior mandibular molars.Result: The mesiobuccal site of mandibular first molar was the deepest part of Von Spee’s curve, and vertical eruption of lower incisal teeth were more related to depth of Von Spee’s curve as compared to vertical eruption of mandibular molars.Conclusion: Vertical eruption of the mandibular molar teeth make significant contribution to the depth of Von Spee’s curve in Class II Division 2 malocclusion.

Wolf spider burrows from a modern saline sandflat in central Argentina: morphology, taphonomy and recognition of fossil examples

Pavocosa sp. (Lycosidae) burrows found in an open sparsely vegetated area on the edge of the saline lake the “Gran Salitral”, in central Argentina, are described. Burrows were studied by capturing the occupant and casting them with dental plaster. The hosting sediments and vegetation were also characterized. Inhabited Pavocosa sp. burrows display distinctive features as open, cylindrical, nearly vertical, silk lined shafts about 120 mm long, subcircular entrances, a gradual downward widening, and a particularly distinctive surface ornamentation in the form of sets of two linear parallel marks at a high angle to the burrow axis. Instead, casts of vacated Pavocosa sp. burrows showed some disturbances caused either by the reoccupation by another organism or by predation of the dweller. Two morphologies are related to reoccupation of burrows: those with a structure in form of an "umbrella” and another with smaller excavations at the bottom of the burrow. Predation by armadillos produces funnel-shaped burrows. Both active and abandoned Pavocosa sp. burrow casts are compared with existing ichnogenera and its distinction is discussed. It is argued that key features like the presence of a neck, a downward widening and the surface texture will allow recognition of wolf spider burrows in the fossil record. Fossil wolf spiders are recorded since the Paleogene (possibly Late Cretaceous), so Cenozoic continental rocks can contain wolf spider burrows awaiting recognition. In addition, the particular distribution of Pavocosa sp. in saline lakes may imply that this type of burrows are linked to saline environments.

Wolf spider burrows from a modern saline sandflat in central Argentina: morphology, taphonomy and recognition of fossil examples

Pavocosa sp. (Lycosidae) burrows found in an open sparsely vegetated area on the edge of the saline lake the “Gran Salitral”, in central Argentina, are described. Burrows were studied by capturing the occupant and casting them with dental plaster. The hosting sediments and vegetation were also characterized. Inhabited Pavocosa sp. burrows display distinctive features as open, cylindrical, nearly vertical, silk lined shafts about 120 mm long, subcircular entrances, a gradual downward widening, and a particularly distinctive surface ornamentation in the form of sets of two linear parallel marks at a high angle to the burrow axis. Instead, casts of vacated Pavocosa sp. burrows showed some disturbances caused either by the reoccupation by another organism or by predation of the dweller. Two morphologies are related to reoccupation of burrows: those with a structure in form of an "umbrella” and another with smaller excavations at the bottom of the burrow. Predation by armadillos produces funnel-shaped burrows. Both active and abandoned Pavocosa sp. burrow casts are compared with existing ichnogenera and its distinction is discussed. It is argued that key features like the presence of a neck, a downward widening and the surface texture will allow recognition of wolf spider burrows in the fossil record. Fossil wolf spiders are recorded since the Paleogene (possibly Late Cretaceous), so Cenozoic continental rocks can contain wolf spider burrows awaiting recognition. In addition, the particular distribution of Pavocosa sp. in saline lakes may imply that this type of burrows are linked to saline environments.