Today, direct composite fillings have reached a satisfactory level, aesthetically and functionally, to replace decayed or lost tooth tissue. However, as the bond degrades with time, the restoration lifetime is limited, depending largely on the type of adhesive used. This review examines the processes involved in the adhesion of biomaterials to enamel and dentin. Contemporary adhesives are categorized upon ultra-morphological, chemical and mechanical features, as well as clinical parameters. Apart from these properties, special attention is given to one-step (self-etch) adhesives, as they are aggressively marketed as the most user-friendly adhesives. Nevertheless, in-vitro research has revealed considerable shortcomings related to many of these simplified adhesives. Notwithstanding the amount of n-vitro data available, non-carious class-V clinical trials remain the ultimate test method to assess clinical success. In combination with the prior in-vitro assessment, the following conclusions were drawn : 1) At present, the three-step etch&rinse approach remains the ‘golden standard’ in terms of bonding effectiveness ; 2) Any kind of simplification in the application procedure results in loss of bonding effectiveness ; 3) The today most acceptable trade-off between bonding effectiveness and ease-of-use is a ‘mild’ two-step self-etch approach that combines micro-mechanical interlocking with additional chemical interaction, the latter definitely contributing to the bond stability on the long term.

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The purpose of this research is to study the relationship between Carabelli's trait and tooth crown size in 45,X females and to clarify the effect of the shortage of X chromosome to the dental crown. The subjects comprised eighty-one 45,X females in the Kvantti research collection and Finnish female controls. Dahlberg's reference plaque (1956) was used to determine the score of the Carabelli's trait which was divided into three classes. The scores were compared with the maximum mesiodistal and buccolingual tooth crown diameters. The result showed that the mesiodistal diameters in 45,X females were significantly smaller than control females, while no association was found between Carabelli's trait and buccolingual tooth crown diameter in 45,X females. Mesiodistal tooth crown diameter was thought to be a key factor to develop the Carabelli's trait in 45,X females.

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The dental impressions of the Pumi tribe, one of the Chinese ethnic minorities, were taken in Lijiang in Yunnan Province in February, 2002. The subjects were young adults and the frequencies of 22 dental traits of 7 maxillary and 2 mandibular teeth were recorded. The results were compared with those of previous studies including Chinese minorities, Dai, Hani and Naxi, and with other Asian populations. A principal coordinate analysis based on Smith's Mean Measure of Divergence using the frequencies of 17 traits suggested that the Pumi tribe belonged to the Sundadont dentition category, which typifies Southeast Asians and positioned close to the Dai and Hani, but a little distant from the Naxi. Other anthropological and linguistic studies also suggest that the Pumi are closely related to Tibetans. Based on our findings, and presumed past and present distributions of Sinodonty and Sundadonty, it was suggested that the Pumi in Yunnan Province have genetically inherited traits similar to the Sundadont peoples of Southeast Asian and other three minorities in Yunnan Province, but also indicated that the traits in the Pumi were environmentally induced probably from other Sinodont tribes such as the Han in their vicinity.

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Our dental school allocates time to endodontic practicals to 4^th-year students who have completed the 3^rd-year course in endodontics. In this term, students practice access opening on extracted upper human single root premolars. All of the teeth were donated by students and the effectiveness of this approach for teaching was analyzed. Although all students were able to find the canal orifices of teeth with one root canal orifice, they could correctly find both orifices in 84.6% of teeth with two root canal orifices. Perforation occurred in 9.3% of the upper premolars. Knowledge of tooth anatomy is essential for students studying endodontic practice. Future efforts should be directed at improving endodontic education to ensure that failure does not occur in practice.

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To evaluate the coexistence of Candida in potentially malignant oral mucosal lesions : inflammatory lesions without features of leukoplakia and lichen planus (IL), lichen planus and leukoplakia using exfoliative cytology (EC). This was evaluated and compared with clinical findings, histopathology, immunohistochemistry and flow cytometrical analysis (FCMA). In order to assess the coexistence of Candida with inflammation, lichen planus and leukoplakia, the smears were taken for Papanicolaou staining. To improve accuracy, PAS staining was performed. Forty-nine cases of smears with biopsy specimens were used for comparative study of EC and histopathology. Also, the immunohistochemical activity of these cases was measured using p53, Ki-67 and COX-2. As for FCMA, the D.I. and P.I. were calculated for all EC smears. One hundred and seventy-five cases of EC smears were obtained from 40 normal tissue samples (control), inflammatory lesions (IL) ｢42｣, lichen planus ｢49｣ and leukoplakia ｢44｣. Clinical findings revealed the presence of whitish patches with erythema in lichen planus and leukoplakia, except for IL where erythema was present in all cases. Overall, 70 cases (40.0%) were confirmed by PAS to contain Candida in the smear : IL ｢20｣, lichen planus ｢24｣, and leukoplakia ｢26｣ with the coexistence rate of 47.6%, 49.0% and 59.1%, respectively. The cytological atypia in these cases was stronger than those without Candida, but was different from dysplastic change. Forty-nine cases (28.0%) were available for immunohistochemical investigation where both smear and histopathology specimens were taken. The mutation of p53, cell proliferation Ki-67 and inflammatory index of COX-2 ; related with prostaglandlins, were also elevated in cases coexisted with Candida. FCMA showed higher aneuploidy (D.I.) in cases with Candida : 1.8 for IL, 2.1 for lichen planus and 2.2 for leukoplakia, respectively. Those without Candida were 1.5, 1.9 and 2.0, respectively. The P.I. also showed the same tendency. Generally, Candida coexisted with these lesions found in Papanicolaou and PAS stainings showed an increased cytological atypia. Immunohistochemical results showed higher positive reaction of p53, Ki-67 and COX-2 in Candida infected diseases than those without Candida. The results indicated a strong relationship with the FCM findings. The study concluded the DNA alterations in cases coexisted with Candida was likely to be considered as irritative factor or promoter of dysplastic changes. The higher aneuploidy and proliferative index, and the immunohistochemical results gave significant indications that candidal infection may disturb the DNA cellular content.

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Antigen delivery systems have been designed to facilitate the development of vaccines that induce both mucosal and systemic immune responses. Transcutaneous immunization (TCI) is a new method of vaccination that can induce both mucosal and systemic immunities. However, because most protein antigens are rather weak immunogens when given transcutaneously, the development of effective adjuvants is of central importance for TCI. In this study, we assessed the potential for the use of oligodeoxynucleotides containing cytosine-phosphate-guanosine motifs (CpG), as an adjuvant for transcutaneous immunization. When female C57BL/6 mice were immunized with tetanus toxoid (TT) by direct application to shaved skin, a TT-specific serum IgG antibody response was induced ; however, no response was induced in feces. When TT was given together with CpG oligonucleotide (ODN) as an adjuvant, a higher TT-specific serum IgG and IgA antibody response was induced, compared to TT alone. Furthermore, a TT-specific IgA antibody response was detected in the fecal extract of mice immunized with CpG ODN. Dose response studies established that 500 μg of CpG induced the highest fecal anti-TT antibody response. These results suggest that transcutaneous administration of CpG as an adjuvant is effective for the induction of mucosal and systemic antigen-specific antibody responses and that CpG could be used as an adjuvant for transcutanous immunization.

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Enhancement of the adhesion and migration of osteoblastic cells on a titanium surface are believed to increase the successful rate of implant therapy. The molecular basis of cell adhesive and migratory interactions with extracellular matrix molecules is dependent on specific adhesive functional motif sequences. These short peptide sequences, known as RGD in adhesion molecules, are thought to serve as a binding site for plasma membrane integrins. In this study, to clarify the usefulness of synthetic peptides for osteoblast attachment, we designed several short RGD-motif peptides from adhesion molecules and examined the attachment level to the osteoblastic cell line MC3T3-E1. To examine how well those designed peptides attach to MC3T3-E1 cells, we performed a competition assay using soluble RGD-motif peptides. Among those peptides used, the GRGDSP peptide derived from fibronectin not only expressed the highest binding activity to MC3T3-E1, but also increased in a dose-dependent manner. These findings suggest that the GRGDSP peptide may be useful in the development of functional titanium implants.

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In this study, innervation of dental pulp in the tooth of green iguana (Iguana iguana) was investigated. Cryosections of dissected maxillae and mandibles were examined by free-floating technique with anti-PGP9.5 antibodies and anti-S-100 protein antibodies, and identified by electron microscopy. Immunoreactive fibers were observed in the pulp. They appeared to be a mixture of myelinated and unmyelinated fibers with small varicosities and were distributed in the pulp along the gap between the tooth and the jaw bone. Dental pulp of polyphyodonts has not been investigated much as replacement of teeth occurs in succession. These findings may promote investigations that could improve our understanding of the function of dental pulp in reptiles.

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