Specific staining of the extracellular matrix components is especially helpful in studying tissue remodeling, particularly in the case of connective tissue pathologies. As developed by Junqueira and colleagues in 1979, specific staining by Picrosirius red is one of the most important stains to study collagen networks in different tissues. Under polarized light, collagen bundles appear green, red or yellow, and are easily differentiated from the black background, thus allowing for quantitative morphometric analysis. As Junqueira and colleagues point out, many studies use color staining to differentiate collagen bundles and to specify collagen types, yet other studies report that polarized colors only reflect fiber thickness and packing. Using a simple histological example, our study illustrates the inability of Picrosirius red staining to differentiate collagen types, since the absorbed amount of polarized light by this dye strictly depends on the orientation of the collagen bundles.
Background: The respective abilities of the GOHAI and OHIP-14 to discriminate between aged patients with different levels of oral diseases have rarely been studied in developing countries. The aim of this study was to compare the discriminative abilities of the OHIP-14 and the GOHAI in an elderly Lebanese population, and particularly to identify persons with different masticatory function.Methods: A sample of elderly, aged 65 years or more, living independently was recruited in two primary care offices in Beirut, Lebanon. Data were collected by means of personal interview and clinical examination. The Arabic OHIP-14 and GOHAI questionnaires were used after cultural adaptation for use in Lebanon. The internal consistency, reproducibility and concurrent validity were verified. To test their discriminative abilities, the ADD (GOHAI and OHIP) and SC (GOHAI and OHIP) scores were dichotomized according to the 25thand 75thpercentile respectively and logistic regressions were conducted using socio-demographic, clinical and subjective explanatory variables.Results: Two hundred and six participants were included; mean age was 72 years and 60% were women. Good psychometric properties were observed for both questionnaires for internal consistency (Cronbach’s alpha>0.88), reproducibility (ICC>0.86) and concurrent validity. Strong correlations were found between GOHAI and OHIP-14 scores but a high prevalence of subjects with no impact was observed using the OHIP-14. Both questionnaires were able to discriminate between participants according to age, perception of temporomandibular joint (TMJ) pain or functional status as represented by the number of dental Functional Units (FU). GOHAI was more discriminant since it identified participants with high dental care needs: high numbers of decayed teeth, low numbers of teeth and socially deprived status.Conclusions: Lebanese elderly with high dental care needs and impaired oral health were identified more easily with the GOHAI. These results may guide the choice of dental indicators to use in a national geriatric survey.
31 July 2012 in International Journal of Dentistry
Purpose. The aim of this study was to investigate the influence of chemical and physical properties of two graft materials on the rate of resorption.Materials and Methods. Direct sinus graft procedure was performed on 22 patients intended for implant placement. Two types of graft materials were used (Bio-Oss and Cerabone) and after 8 months healing time the implants were inserted. Radiographic assessment was performed over the period of four years. Particle size, rate of calcium release, and size and type of crystal structure of each graft were evaluated.Results.The average particle size of Bio-Oss (1 mm) was much smaller compared to Cerabone (2.7 mm). The amount of calcium release due to dissolution of material in water was much higher for Bio-oss compared to Cerabone. X-ray image analysis revealed that Bio-Oss demonstrated significantly higher volumetric loss (33.4 3.1%) of initial graft size compared to Cerabone (23.4 3.6%). The greatest amount of vertical loss of graft material volume was observed after one year of surgery.Conclusion. The chemical and physical properties of bone graft material significantly influence resorption rate of bone graft materials used for sinus augmentation.
Objective: To determine if resonance frequency analysis (RFA) correlated with insertion torque (IT), bone volume (BV), and clinical osseointegration at 6 weeks. Materials and Methods: For 18 patients, BV was evaluated histologically by retrieving bone core biopsies before placement of 40 dental implants. Peak IT was recorded at implant placement, and RFA values (implant stability quotient [ISQ]) were noted at baseline, 3 weeks, and 6 weeks. Osseointegration was evaluated at 6 weeks when torquing abutments to 30 N. ISQ values were correlated with IT, BV and abutment torquing results. Data were statistically analyzed. Results: ISQ values significantly decreased at 3 weeks and increased at 6 weeks. There was a significant positive correlation between BV and ISQ at baseline and at 3 weeks, but not at 6 weeks, and between ISQ and jaw location, implant diameter and IT at baseline, 3 weeks, and 6 weeks. There was a significant correlation between spinning/painful implants during abutment torquing and low ISQ, low BV, and low IT values. Conclusion: Correlations between BV and IT values, and ISQ suggest that RFA may indicate primary implant stability. BV, IT, and ISQ values may anticipate the degree of osseointegration at 6 weeks.
: Establish a correlation between dental implant insertion torque (IT) and bone density. : In 18 patients, implant site preparation was initiated using a trephine drill to retrieve a bone biopsy and completed with standard drills. Bone type was assessed during drilling according to surgeon's tactile sense. Forty implants were placed and peak IT values were recorded. Osseointegration was evaluated clinically at abutment connection. Data were analyzed using Pearson product-moment correlation coefficient. : All implants but one achieved osseointegration. D1 and D4 bone types were significantly assessed using tactile sense. IT values ranged from 15 to 150 Ncm with a mean value of 78.30 Ncm. Mean IT was significantly higher in D1 bone (126.67 Ncm) and lower in D4 bone (40.22 Ncm) (P value <0.0001), whereas intermediate values were noted in D2 and D3 bone with no significant difference between these bone types (P value = 0.462). Statistically significant correlation was found between bone volume and IT values (r = +0.771, P < 0.0001). No statistically significant correlation was found between implant length and/or diameter and IT in all bone densities. : Clinical assessment of bone density during drilling may be achieved in hard and soft bone but not in intermediate densities. Increasing peak IT values correlated with increasing bone volume. High IT does not seem to alter osseointegration process.