ABSTRACT
BACKGROUND: Lack of seal and adhesion between the final restoration and tooth structure adversely affects the results of root canal treatment. Lots of adhesive bonding agents are marketed to overcome this deficiency and achieve successful restoration. So the study compares and evaluates the micro shear bond strength of coronal dentin and pulp chamber dentin using three different generation dentin bonding systems and to know clinical efficiency for clinical use. MATERIALS AND METHODS: DIFFERENT GENERATION DENTIN BONDING SYSTEMS USED WERE: (1) One bottle total etch system (XP Bond-5(th) generation), (2) Two-step self-etch system (Clearfil SE Bond-6(th) generation) and (3) All-in-one system (G Bond-7(th) generation). Thirty human mandibular molars were collected out of which sixty samples were prepared by sectioning each tooth into coronal dentin and pulpal floor dentin. They were divided into two major groups. Group I: 30 Coronal dentin samples. Group II:30 Pulpal floor dentin samples. Both the groups were further subdivided depending on the bonding agent used. Subgroup Ia:XP Bond, Subgroup Ib:Clearfil SE Bond, Subgroup Ic:G Bond, Subgroup IIa:XP Bond, Subgroup IIb:Clearfil SE Bond, Subgroup IIc:G Bond. Resin composite was bonded to these samples and tested for micro-shear bond strength. The mean bond strengths and standard deviations were calculated and analyzed using one-way ANOVA test and Student's t-test (unpaired) and honestly significant difference post-hoc tests. RESULTS: Coronal dentin showed higher values of micro shear bond strength than the pulpal floor dentin. All-in-one system (G Bond) showed least bond strength values to both the regions coronal dentin and pulpal floor dentin. CONCLUSION: Factors affecting the shear bond strength are dependent on material (adhesive system), substrate depth and adhesive/depth interaction. Hence composition and substrate treatment should be considered for good adhesive. Chemical composition of adhesive system determines clinical successes.
ABSTRACT
BACKGROUND: Since ancient times, use of graft materials to promote healing of defects of bone is wellknown. Traditionally, missing bone is replaced with material from either patient or donor. Multiple sources of bone grafts have been used to graft bone defects to stimulate bone healing. Hydroxyapatite is naturally occurring mineral component of bone, which is osteoconductive. This versatile biomaterial is derived from many sources. The aim of this study is to evaluate the efficacy of eggshell derived hydroxyapatite (EHA) in the bone regeneration of human maxillary cystic bone defects secondary to cystic removal/apicoectomy and compare the material properties of EHA in vitro. MATERIALS AND METHODS: A total of eight maxillary bone defects were grafted after cystic enucleation and/or apicoectomy in the year 2008 and completed the study at 1 year. The patients were followed-up 2 weeks after surgery for signs and symptoms of infection or any other complications that may have been related to surgical procedure. Follow-up radiographs were obtained immediately after surgery followed by 1, 2, and 3 months to assess the efficacy of EHA in bone healing. Physicochemical characterization of the EHA was carried out in comparison with synthetic hydroxyapatite (SHA), also compared the biocompatibility of EHA using in vitro cytotoxicity test. RESULTS: By the end of the 8(th) week, the defects grafted with EHA showed complete bone formation. However, bone formation in non-grafted sites was insignificant. The values of density measurements were equal or more than that of surrounding normal bone. These results indicate that the osseous regeneration of the bone defect filled with EHA is significant. EHA showed the superior material properties in comparison with SHA. CONCLUSION: EHA is a versatile novel bone graft substitute that yielded promising results. Because of its biocompatibility, lack of disease transfer risks, ease of use and unlimited availability, EHA remains a viable choice as regenerative material. EHA is very cost-effective, efficient bone graft substitute, which can be prepared in a very economical way. It is a worthwhile bone substitute because it is safe and easily available material. How to cite the article: Kattimani VS, Chakravarthi PS, Kanumuru NR, Subbarao VV, Sidharthan A, Kumar TS, Prasad LK. Eggshell derived hydroxyapatite as bone graft substitute in the healing of maxillary cystic bone defects: A preliminary report. J Int Oral Health 2014;6(3):15-9.
ABSTRACT
BACKGROUND: Orthodontists have several methods to detect inter arch-tooth size discrepancies in patients presenting for orthodontic treatment. Many methods such as Pont's analysis, Nance and Carey's analysis, Peck and Peck ratio, Bolton's analysis are commonly used methods. A thorough search of literature reveals a paucity of reliable data on the mesiodistal dimensions of the crowns of the permanent dentition of Indian population. Without information about the size of individual tooth and groups of teeth for Indian population, it is difficult for the clinician to make an adequate diagnosis and treatment plan and to carry out a plan of therapy. AIM: To determine the size of individual permanent tooth and the sex differences, with tooth size ratios according to Bolton's formula and to evaluate the reliability of Bolton's norms (Anterior/ Posterior) in Indian population. MATERIALS AND METHODS: One hundred and twenty cases in which an excellent occlusion was naturally existent with the mean age of 22 years (18-27 years) were selected in the study. The casts were prepared after taking alginate impression of maxillary and mandibular arches and pouring them immediately with dental stone. A sliding Digital Vernier calliper used to measure the teeth. The ratios of the mean of mesiodistal dimensions of types of teeth were computed. RESULTS: The mean overall ratio for the Indian population is found to be 92.11 with a standard deviation of 2.12. The values ranged from 86.50-97.13 and the median is 92.16. The mean anterior ratio for the Indian population is found to be 78.14 with a standard deviation of 2.59. CONCLUSION: Bolton's original data does not represent Indian population. In our study greater size variability was found in maxillary teeth as compared with mandibular teeth except mandibular first molar. Our study indicated that population-specific standards are necessary for clinical assessments. Significant differences were shown for the overall ratio and anterior ratio for both sexes as compared to Bolton's ratio.
