Investigation of natural head posture in different head types

The aim of this study was to investigate natural head posture (NHP) in different head types. Lateral cephalograms of 99 adults (Mean age, 21.8 years +/- SD, 2.2 yrs, range between 19 and 29 yrs) were examined. Head types were determined as Hyperbrachycephal, Brachycephal, Mesocephal or Dolichocephal according to the cephalic index. Analysis of variance and the Duncan's test were performed to assess inter-group differences for the parameters. The findings revealed that, NHP was statistically not different between the head type groups. Thus, it was suggested that environmental factors during growth may alter NHP, as well as craniofacial morphology but in a different manner (i.e. degree and direction) in each head type.     

Clinical evaluation of the plaque-removing ability of three different toothbrushes in a mentally disabled group

The aim of the study was to evaluate the efficacy of plaque removal of three different toothbrushes on mentally disabled children in two different age groups. A manual triple-headed brush (SuperBrush; Dento Co. AS [junior, regular]) compared with a new manual toothbrush (CrossAction; Oral-B [35 compact, 40 regular]) and an electric toothbrush with an oscillating rotating head (Braun Plaque Control 3D [Braun 3D]; Oral-B [D15525]). Fifteen children aged 6-12 (Group A) and 15 children aged 13-18 (Group B) with mild mental disabilities participated in the single-blind clinical study. To obtain a plaque-free condition at baseline, professional tooth-cleaning was performed on each participant. After instructions on how to use the toothbrushes, each group started the experiment. After 1 week of application, the Quikley Hein (QH) plaque index and the approximal plaque index (API) were used to assess the oral hygiene status of each participant. This was followed by a week of recess before each group switched to the next type of toothbrush. The study lasted for 5 weeks. Compared to the two other brushes, the Braun 3D was more effective in removing plaque (means of QHI: 1.54 (Braun 3D), 1.77 (SuperBrush), and 2.15 (CrossAction) in total; means of API 1.37 (Braun 3D), 1.52 (SuperBrush), 1.94 (CrossAction). The study indicated that the electric toothbrush is the most effective for removing dental plaque in mentally disabled children, whereas the SuperBrush is a good alternative.     

Thermal and pH changes,and dimensional stability in irreversible hydrocolloid impression material during setting

Present study the relation between pH, thermal changes and dimensional stability during setting of irreversible hydrocolloid impression materials was investigated. Ten specimens of each product were prepared for different measurements: Thermal, pH changes and dimensional stability (mass and linear). Thermal and pH readings for 20 min and dimensional measurements for a 2 hr period were taken after mixing. It was observed that pH and thermal values changed in relation to different materials, while they did not change with the time according to variance analysis results. On the other hand, dimensional stability showed significant differences with time in all tested impression materials. A continuous pH change was observed with the time of gelation in all irreversible hydrocolloid impression materials tested. Dimensional stability also showed significant differences with time in all impression material and as a result hydrocolloids with a high pH showed better dimensional stability than those with a low pH.     

Use of polyethylene ribbon to create a provisional fixed partial denture after immediate implant placement: a clinical report

Provisional restorations are generally necessary to restore lost function and esthetics during the implant integration period. This article describes the fabrication of an esthetic, economic, and conservative bonded provisional fixed partial denture for a patient restored with implants. A reinforcing polyethylene ribbon was used to bond the natural lateral incisors to the adjacent teeth. An acceptable esthetic outcome was obtained, and the result was satisfactory to the patient.     

The normal and pathological pigmentation of oral mucous membrane: a review

Pigmentation is both the normal and abnormal discoloration of oral mucous membrane. Pigmentation has multifactorial etiology. Most of the pigmentation is physiologic but sometimes it can be a precursor of severe diseases. Melanin pigment irregularities and color changes of the oral tissues could provide significant diagnostic evidence of both local and systemic disease. The differential diagnosis, clinical, etiology, and histopathological features of pigmentation are discussed and the current literature is reviewed.     

Effect of light-emitting diode on bond strength of orthodontic brackets

The aim of this study was to evaluate the effect of light-emitting diode (LED) light curing on shear bond strength (SBS) of orthodontic brackets bonded to teeth. Light exposure of 40 seconds from a conventional halogen-based light-curing unit was used as a control. Eighty human premolars were divided into four groups of 20 each. Brackets were bonded to acid-etched teeth with Transbond XT light-cured adhesive. In the first group, the adhesive was light cured for 40 seconds with a conventional halogen unit (XL3000, 3M). In the other three groups, adhesive was cured with a commercial LED unit (Elipar FreeLight, 3M ESPE) for 10, 20, or 40 seconds. SBS of brackets was measured on a universal testing machine and recorded in megapascals. Adhesive remnant index (ARI) scores were determined after failure of brackets. Data were analyzed using analysis of variance and chi-square tests. No statistically significant differences were found among the SBS values of halogen-based light-cured (13.1 +/- 3.1 MPa) and 20- and 40-second LED-cured (13.9 +/- 4.8 MPa and 12.7 +/- 5.1 MPa) specimens (P > .05). However, 10 seconds of LED curing yielded significantly lower SBS (P < .05). No statistically significant differences were found between the ARI scores among groups. The results of this study are promising for the orthodontic application of LED-curing units, but further compatibility and physical characteristic studies of various orthodontic adhesives and clinical trials should be performed before validation.     

Vascular endothelial growth factor in gingival tissues and crevicular fluids of diabetic and healthy periodontal patients

BACKGROUND: Periodontal disease is one of the major oral problems encountered in patients with diabetes mellitus (DM). Vascular changes, neutrophil dysfunction, altered collagen synthesis, and genetic predisposition observed in DM may contribute to periodontitis; and the vascular alterations observed in such patients may depend on vascular endothelial growth factor (VEGF) actions. Few reports are available about the mechanism of neovascularization and the angiogenic factors that contribute to the periodontal pathology and the role of VEGF in periodontal diseases. The aim of this study is to compare VEGF expression in healthy and periodontally diseased tissues with gingival crevice fluid (GCF) of healthy persons and diabetic patients. METHODS: Gingival tissue and GCF samples were collected from sites of periodontitis in 10 healthy subjects and in 10 type 2 diabetic patients, and from the sites of healthy gingiva within the same groups. Therefore, each patient became his/her own control. Additionally, 10 people without any systemic or periodontal diseases were enrolled, forming a negative control group. Thus, a total of 50 tissue and 50 GCF samples were provided. RESULTS: No VEGF staining was observed in the negative control group or in the systemically healthy people's healthy tissue samples, whereas four samples of diabetic patients showed positive staining (P < 0.05). However, VEGF was revealed in two tissue samples of periodontal sites of systemically healthy people and in six samples of the diabetic patients (P > 0.05). In all test groups, GCF VEGF levels were higher in periodontal sites (P < 0.05) than in healthy sites. CONCLUSION: The results of this study showed that VEGF is increased in all periodontal tissues of both groups and in the healthy sites of diabetic patients. Additionally, GCF VEGF values increased in periodontal sites of all test groups.     

In vitro fracture resistance of posterior metal-ceramic and all-ceramic inlay-retained resin-bonded fixed partial dentures

STATEMENT OF PROBLEM: Inlay-retained resin-bonded fixed partial dentures (RBFPDs) are conservative prosthetic restorations; however, their resistance to fracture is not clear. PURPOSE: The purpose of this study was to compare fracture loads of posterior complete coverage metal-ceramic restorations with all-ceramic inlay-retained RBFPDs. MATERIAL AND METHODS: Thirty-two posterior ceramic RBFPD restorations were divided into 4 groups (n=8): (1) Complete metal-ceramic fixed partial dentures (MC-FPDs) fabricated of Ni-Cr-based alloy (Wirolloy) and veneered with a ceramic (IPS d.SIGN) as the control group; (2) inlay-retained metal-ceramic (MC RBFPDs) with the same materials as the control; (3) inlay-retained lithium disilicate (LD) glass-ceramic (IPS Empress 2) RBFPDs; and (4) inlay-retained zirconia-based (Z) ceramic (Cercon) RBFPDs. Control specimens were prepared to receive conventional complete MC-FPDs designed to include a 1.3-mm-circumferential, 90-degree flat shoulder with rounded angles. Inlay-retained RBFPD specimens were prepared with 2-mm occlusal reduction but without bevels at the occlusal or gingival margins. Specimens were loaded and fracture loads (N) measured at fracture with a universal testing machine at a crosshead speed of 1.0 mm/min and 250 kgf load cell. Data were analyzed with 1-way ANOVA and Duncan test (alpha=.001). RESULTS: Fracture loads (mean +/- SD) were greatest for control specimens (1318.43 +/- 211.00 N) and Z-RBFPD (1247.70 +/- 262.51 N) specimens as compared to MC-RBFPD or LD-RBFPD (P < .001). MC-RBFPD exhibited the next highest fracture loads (958.01 +/- 194.29 N), and LD-RBFPD exhibited the significantly lowest values (303.23 +/- 92.54 N) of the materials tested (P < .001). CONCLUSION: Inlay-retained zirconia-based ceramic RBFPDs demonstrated the greatest fracture resistance among all inlay-retained restorations tested.     

The comparison of various oral hygiene strategies in neuromuscularly disabled individuals

BACKGROUND: This study aims to investigate the effect of various oral hygiene strategies on the symptoms of inflammation in neuromuscularly disabled patients and to define the optimum hygiene method. METHODS: Fifty-nine neuromuscularly disabled participants, suffering from cerebral palsy, were randomly divided into five groups as follows: Group M: manual toothbrush (n=14), Group E: electrically powered toothbrush (n=9), Group MC: manual toothbrush and chlorhexidine gluconate (CHX) spray (n=13), Group EC: electrically powered toothbrush and CHX spray (n=9), and Group C: CHX spray (n=14). The oral hygiene applications were provided by the parents and staff. At baseline and after 21 days the plaque index (PI), the gingival index (GI), and bleeding on probing (BOP) were recorded. RESULTS: In intra-group comparisons of the pre- and post-application scores, in all groups the PI and GI scores and BOP percentages, except in Group C, were found significantly different (p<0.05). There were significant differences among the post-application scores, between Group M and Group E and between Group C and Group E in PI scores; between Group C and Group E the difference in GI scores were found statistically significant (p<0.05). CONCLUSIONS: Although all oral hygiene strategies reduced plaque and gingival inflammation, the results of our study suggested the electrically powered toothbrush could be more recommendable to neuromuscularly disabled people in these strategies, while the combined procedures appeared to be neither beneficial nor favorable.     

Temporalis muscle flap for craniofacial reconstruction after tumor resection

Temporalis muscle flap provides a good solution for the reconstruction of craniofacial defects after tumor resection. Nine patients with complicated defects located at the upper two thirds of the face, anterior cranial base, or mastoid region are presented. Five patients had orbital exenteration, two with total maxillectomy and two with anterior craniofacial resection. Temporalis muscle flap provided profuse well-vascularized tissue for the obliteration of orbital exenteration and total maxillectomy cavities and coverage of surface defects. Cranial, oral, and nasal spaces were separated successfully in all patients. Temporalis muscle flap is a very reliable technique with low complication rates and few donor site problems. This safe and technically easy flap can be preferred for the reconstruction of craniofacial defects after ablative tumor surgery, especially in older and debilitated patients.