Ching-Fang Tsai

Measurement of prostaglandin E2 and leukotriene B4 in the gingival crevicular fluid

UNLABELLED The arachidonic acid metabolites prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) are inflammatory mediators which are likely to be involved in the pathogenesis of periodontal disease. PGE2 mediates vasodilatation, increases vascular permeability, enhances pain perception by bradykinin and histamine, alters connective tissue metabolism and enhances osteoclastic bone resorption. LTB4 causes the accumulation of inflammatory cells in the inflamed sites, and degranulation of polymorphonuclear leukocytes. OBJECTIVE To measure gingival crevicular fluid (GCF) levels of PGE2, LTB4 and periodontal health. METHODS The periodontal condition of 24 subjects was evaluated on the basis of plaque index, gingival index, probing depth, and attachment level. GCF samples were collected from one or two site(s) of each sextant per subject and the volume was measured using Periotron 6000. Samples were then assayed for PGE2 and LTB4 using a competitive enzyme immunoassay. Mean PGE2 and LTB4 levels were determined for each subject and group means compared. RESULTS Significant differences in the levels of PGE2 and LTB4 were found between patients with periodontitis, and non-periodontitis individuals (P < 0.001). The PGE2/LTB4 levels were positively correlated with the clinical parameters (P < 0.01) and reduced markedly after phase 1 of the periodontal treatment (P < 0.01). The total amount and concentration (ng ml-1) of LTB4 was positively correlated with the gingival index (P < 0.01). CONCLUSIONS These results indicate that the levels of PGE2 correlated with the severity of the periodontal status, and the levels of LTB4 correlated with gingival inflammation. Thus, our data suggest that the total amounts of PGE2/LTB4 may be good indicators for periodontal inflammation.

Three-dimensional relationship of the maxillary anterior teeth to the incisive papilla in young adults.

The use of the incisive papilla as an important guide for setting maxillary teeth has been applied in prosthetic dentistry. The purpose of this study was to estimate the relationship between maxillary anterior teeth and the incisive papilla of young adults with approximately optimal occlusion in Taiwan. Study casts of 100 young adults (50 males, 50 females; mean age, 22.4 years) were selected in this study. All of the marked points on maxillary casts were measured using a three‐dimensional precise measuring device. The relative positions of maxillary teeth landmarks to incisive papilla were measured and analyzed using SAS software (JMP 4.02). Students t test and Pearsons correlation test were used to test the statistical significance of any differences (p < 0.05). The results showed that the mesiolabial incisal edge of the upper central incisor was 7.30 ± 0.64mm anterior to the center of the incisive papilla. There was no significant difference in gender (p > 0.05). The intercanine line was 0.27 ± 1.30 mm posterior to the center of incisive papilla. There was no significant difference in gender (p > 0.05). The horizontal distances of the mesiolabial incisal edge of the upper central incisor and the intercanine line to the center of the incisive papilla showed only weak correlation (r < 0.5). In addition, the three‐dimensional relationship of maxillary anterior teeth to the center of the incisive papilla was measured and analyzed. We suggest using the incisive papilla as a reference landmark for the setting of maxillary anterior teeth.

Uprighting Impacted Mandibular Permanent Second Molars with the tip-back Cantilever Technique Cases Report

Very severe inclination of the mandibular second molar is a difficult challenge for dentists. Severe impaction of the mandibular second molars often leads to their extraction to avoid potential damage to the root of the first molars and provide space for the eruption of the third molars. An ideal treatment is orthodontic uprighting with or without surgical uncovering, and one of the effective appliances for molar uprighting is the tip-back cantilever technique. This paper presents the successful tip-back sectional archwire orthodontic treatment of impacted mandibnlar second molars.

Immediate implant placement following minimally invasive extraction: a case report with a 6-year follow-up.

Single tooth replacement with a dental implant has become an increasingly favored treatment option in the anterior maxilla; however, bone resorption following maxillary anterior tooth extraction is very common and often compromises gingival tissue for the implant restoration. Achieving predictable peri‐implant esthetics requires a proper understanding and preservation of the osseous and gingival tissue surrounding the failing tooth. Therefore, the key to maintaining the interproximal papillae is to preserve the osseous support with minimally invasive extraction. An immediate implant insertion after tooth extraction may maintain the crest bone and the interdental papillae, thus achieving peri‐implant esthetics. This article describes the detailed treatment planning and meticulous techniques in immediate implant placement that reduce treatment time and maintain functional as well as esthetic results through a 6‐year follow‐up.

Immediate provisional restoration of a single-tooth implant in the esthetic zone: A case report

Immediate implant restoration of single implants may demonstrate a positive effect on peri‐implant soft tissue. Placement of a provisional restoration following implant surgery can create soft tissue contours that resemble normal gingival topography before placement of the definitive prosthesis. This article describes a staged approach of the mandibular permanent right central incisor, which was congenital missing. The proper space for restoration of the missing incisor was created through orthodontic treatment. The scheduled implant site was reconstructed using autogenous bone harvested from the chin region. After a healing period of four months, an implant was installed with the connection of a fixed provisional crown to a prefabricated temporary abutment. The soft tissue around the implant healed according to the contours of the provisional restoration and the emergence profile was used to duplicate the definitive restoration. Peri‐implant esthetics was achieved through the staged approach and immediate restoration of the implant.

Comparison of Two Heat-pressed All-ceramic Crown Systems

There is increasing demand for all‐ceramic crowns to improve esthetics and avoid the intraoral use of metal. There are several ways to fabricate all‐ceramic prostheses. The heat‐press method is easily handled, creates less porosity than the conventional powder slurry method, produces consistent quality, and avoids firing shrinkage. Each of the popular brands of heat‐press ceramics has its own heat‐press furnace. The purposes of this study were to determine whether it was possible to use one heat‐press furnace to make different all‐ceramic prostheses, and to compare the fit and hardness of two commercial heat‐press all‐ceramic systems made using the staining technique. Ceramic ingots were analyzed by X‐ray diffraction analysis before heat press. Finesse® All‐Ceramic and OPC 3G® specimens were both heat‐pressed using a porcelain pressing furnace designed for Finesse®. Mesio‐occluso‐distal inlays were cemented to the metal die with temporary cement. Marginal accuracy was measured using a three‐dimensional coordinate measuring machine. Vickers hardness was measured using a microhardness tester. X‐ray diffraction analysis of the ceramic ingots showed that the main peak position for Finesse® was leucite (KAlSi2O6) and for OPC 3G® was lithium disilicate (Li2Si2O5). The marginal gap for Finesse® was statistically lower than that for OPC 3G® (62.5 ± 15.5 vs 99.4 ± 11.6 mm; p < 0.05). There was no statistically significant difference in hardness between Finesse® and OPC 3G® (613.8 ± 49.2 vs 660.0 ± 34.0 kgf/mm2; p > 0.05). The marginal gaps for Finesse® and OPC 3G® were clinically acceptable. Therefore, it is possible to use one heat‐press furnace to cast different all‐ceramic systems.