Lip cavernous hemangioma in a young child

Hemangiomas are benign tumors of infancy and childhood, characterized by a phase of fast growth with endothelial cell proliferation, occurring in 10-12% of children at 1 year of age. It is known that hemangiomas of infancy are most commonly located on the head and neck region (around 60% of cases) and occur more frequently in the lips, tongue, and palate. Approximately 50% of hemangiomas have complete resolution, and 90% of them are resolved up to the age of 9. Complications occur in only 20% of the cases, the most common problem being ulceration with or without infection. The treatment depends on lesion location, size and evolution stage, and the patient's age. Surgery is usually indicated when there is no response to systemic treatments, or even for esthetic reasons, being performed as a simple excision in combination or not with plastic surgery. This paper reports a case of lip cavernous hemangioma in a 4-year-old child, who was submitted to 3 sessions of vascular sclerosis due to the size of the lesion, before undergoing simple excision of the hemangioma. Two years of postoperative clinical follow-up shows treatment success with no recurrence of the lesion.     

Removal torque of zirconia abutment screws under dry and wet conditions

The aim of this study was to verify whether screw abutment lubrication can generate higher preload values compared to non-lubricated screws, a titanium abutment was screwed onto an implant analog and scanned with the Procera System to generate 20 zirconia abutments. MKIII Br?nemark implants were clamped to a precision torque device, and the abutments were distributed in dry and wet groups with 10 specimens each. In the wet groups, the inner threads of the implants were filled with artificial saliva. All abutments were fastened with a Torqtite screw under 32 Ncm. Ten detorque measurements were performed per group pushing the reverse button of the Torque controller soon after screw tightening with values registered. The mean detorque values were calculated and compared by a Student's t test (α=0.05). The wet condition presented significantly higher mean detorque than the dry condition (31.5 ± 1.2 versus 27.5 ± 1.5 Ncm, respectively; p=0.0000024). In conclusion, there was always a loss in the initial torque values when the removal torque was measured under both conditions. The wet condition presented higher mean torque than the dry condition. Better preload values were established in the wet group, suggesting that the abutment screw must be lubricated in saliva to avoid further loosening.     

Genotoxicity of corrosion eluates obtained from endosseous implants

PURPOSE: Commercially pure titanium alloys are currently used as metallic biomaterials in implantology. Corrosion phenomena appear to play a decisive role in metallic implant long-term behavior. Thus, the goal of this study was to examine the genotoxic potential of corrosion eluates obtained from dental implants using Chinese ovary hamster cells in vitro by the single-cell gel (comet) assay. This technique detects deoxyribonucleic acid strand breaks in individual cells in alkaline conditions. MATERIALS AND METHODS: The materials tested included 3 dental implants commercially available. Each of the tested materials was corroded in a solution consisting of equal amounts of acetic acid and sodium chloride (0.1 M) for 1, 3, 7, 14, and 21 days. The Chinese ovary hamster cultures were then exposed to all corrosion eluates obtained from endosseous dental implants for 30 minutes at 37 degrees C. RESULTS: None of the eluates was found to exhibit genotoxicity, regardless of the type of dental implant used. CONCLUSION: The results suggest that all dental implants tested in this study did not induce deoxyribonucleic acid breakage as depicted by the single-cell gel (comet) assay.     

A critical analysis of the degree of conversion of resin-based luting cements

Objective

This study analyzed the degree of conversion (DC%) of four resin-based cements (All Ceram, Enforce, Rely X ARC and Variolink II) activated by two modes (chemical and dual), and evaluated the decrease of DC% in the dual mode promoted by the interposition of a 2.0-mm-thick IPS Empress 2 disc.

Material and Methods

In the chemical activation, the resin-based cements were prepared by mixing equal amounts of base and catalyst pastes. In the dual activation, after mixing, the cements were light-activated at 650 mW/cm² for 40 s. In a third group, the cements were lightactivated through a 2.0-mm-thick IPS Empress 2 disc. The DC% was evaluated in a FT-IR spectrometer equipped with an attenuated total reflectance crystal (ATR). The data were analyzed by two-way ANOVA and Tukey''s HSD test.

Results

For all resin-based cements, the DC% was significantly higher with dual activation, followed by dual activation through IPS Empress 2, and chemical activation (p<0.05). Irrespective of the activation mode, Rely X presented the highest DC% (p<0.05). Chemically activated Variolink and All Ceram showed the worst results (p<0.05). The DC% decreased significantly when activation was performed through a 2.0-mm-thick IPS Empress 2 disc (p<0.05).

Conclusions

The results of the present study suggest that resin-based cements could present low DC% when the materials are dually activated through 2.0 mm of reinforced ceramic materials with translucency equal to or less than that of IPS-Empress 2.     

Severe dental caries is associated with incidence of thinness and overweight among preschool Chinese children

Abstract

Objective: To examine the association of incidence and baseline prevalence of severe dental caries with incidences of thinness and overweight among pre-school Chinese children.

Materials and methods: A longitudinal study design was used. A total of 772 children recruited from 15 kindergartens in Liaoning Province who completed baseline and follow-up assessments were included. The age range of children at baseline was 24.6–71.1 months. BMI-for-age z-score was calculated to estimate incidence of thinness and overweight. Severe dental caries was indicated by pulpal involvement, ulceration, fistula or abscess (pufa). Baseline prevalence of severe caries included children with pufa ≥1, incidence included those who changed from pufa = 0 to ≥1 at follow-up. Logistic regression was constructed to assess the association of baseline prevalence and incidence of severe caries with each of incidence thinness and overweight.

Results: Children with incidence of severe caries had higher odds for incidence thinness (OR: 4.08; 95% CI: 1.08, 15.41). Baseline prevalence of severe caries was not significantly associated with incidence thinness. Participants with severe caries at baseline had higher odds for incidence overweight (OR: 2.33; 95% CI: 1.17, 4.63). The relationship between incidence of severe caries and incidence overweight was insignificant.

Conclusions: The findings suggest a U-shaped relationship between severe dental caries and both ends of anthropometric measures among pre-school Chinese children. The findings highlight the importance of integrating oral and general health promotion policies. Primary health care providers are encouraged to incorporate dental screening, counselling and referral for treatment for severe caries to promote appropriate growth and overall health of children.     

Microscopic qualitative evaluation of fixation time and decalcification media in rat maxillary periodontium

The rat model is widely used in periodontal research and the quality of histological sections is essential. The purpose of this study was to evaluate the histological characteristics of periodontal tissues in Wistar rat maxillae, with different times of fixation and decalcified by nitric acid or formic acid (Anna Morse Solution). Fifteen rats were used. Fixation was performed for 24, 48 and 72 hours. The maxillae were hemi-sectioned and each part was decalcified either in nitric acid for 7 days or in Anna Morse solution for 35 days. Two trained and blinded examiners performed the evaluation. Fourty eight hours of fixation and decalcification with Anna Morse solution showed more clear characteristics of the epithelium-connective tissue interface and of the periodontal structures. Mean measurements between the cementum-enamel junction and the bone crest varied in the different experimental times from 176.5 (+/- 60.45) to 210.94 (+/- 39.33) pixels on the buccal aspect, and from 199.69 (+/- 38.33) to 298.55 (+/-70.81) pixels on the palatal aspect, with no statistically significant differences (ANOVA, p > 0.05). In the same fixation period, decalcification with nitric acid or Anna Morse solution did not display any statistically significant differences. It may be concluded that for a qualitative histological analysis, fixation should preferably be for 48 hours and the demineralization should be made by Anna Morse solution. For a histomorphometric analysis, the decalcification solution does not interfere in the results.     

Simple bone cyst: possible misdiagnosis in periapical pathology

Simple bone cysts are non-neoplastic bone lesions, classified as intraosseous pseudocysts without epithelial lining, that can be empty or filled by fluid and display uncommon clinical and radiographic features. This article presents an unusual case of a simple bone cyst with clinical and radiographic features similar to chronic apical periodontitis. A general dentist referred an 18-year-old man for endodontic treatment after the patient complained of pain in the mandibular right second molar, which displayed a significant bony radiolucency. Chronic periapical lesion was excluded after detailed clinical and radiographic examinations. During surgical exploration, an empty bone cavity was observed and curetted before wound closure. One year later, complete healing was observed.