Craniofacial development plays an important role in the formation of occlusion. It can not be overstated that the key to successful orthodontic treatment for malocclusion resulted from the skeletal imbalance basically relies on through understanding of the growth and development of craniofacial complex and the accurate prediction of their growth pattern.
Until recently the concept of the mean on the absolute and relative growth has been widely accepted for an individual assessment. In addition, it is for more useful to apply relative growth based on biological age than the chronological age.
In this study, we tried to apply the concept of spatial proportional change in body height and some certain parts of the body in an adolescent patient for the statistical prediction of the craniofacial complex.
The sample comprised cross-sectional data of 447 male and 339 female Koreans ranging in age from 6 to 18 years. The records collected were frontal and lateral roentgenocephalo-grams, hand wrist X-ray film and body height on each subject.
Twelve variables were selected for cephalometric analysis to represent the craniofacial morphology. Besides, hand wrist X-ray films were also put to the evaluation of bone maturation as skeletal maturity indicators (SMI). Correlations among chronological age, body height and cephalometric data came out to show the results as follows ;
1. Increase in the coordinate scores of SMI of both male and female was proportional to an increment of age, showing a rapid acceleration in SMI at the age of 10 in male, and 8 in female on average. At SMI coordinate scores 4 and 5, the largest age difference between the sexes was recognized with about 2. 2 years advance in female.
2. As judged according to SMI, growth changes in body height and craniofacial complex showed a wide range of variety in sex and each component of it.
3. Quantified SMI showed a strong correlation with the mandibular body length in both male and female. Although these matched correlations varied considerably, the higher were seen in the newly quantified age division. This might suggest that growth prediction would be possible within a limit of period.

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The dental behavior of older adults is attracting increasing attention. Many studies have been made to understand the dental behavior of older adults in Europe and the United States. On the contrary, few studies have been made about dental behavior in Japan.
The aim of this study was to investigate how sociodemographic factors affect the dental health belief and behavior of Japanese middle-aged and older adults. A total of 278 patients aged 40 years and older who visited the prosthodontic clinic of the Showa University dental hospital were selected for the subjects. Personal interviews regarding their dental knowledge and attitudes were made prior to the dental examinations. One dentist carried out all the dental examinations and interviews. Their educational level and marital status were also examined.
The results showed that sociodemographic factors significantly affected the dental health belief and behavior of Japanese adults. The higher the level of education, the better the oral condition they had. Those with higher education had clearer knowledge and a more positive attitude toward dental health as compared to those less educated. And the higher rate of non-use of denture was found among those who did not have spouse though they needed dentures. The results also indicated the validity of socio-behavioral approach to the dentistry.

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Hexagonal disk-shaped crystals were found in caries-arrested enamel as well as in early and old dental calculi with scanning electron microscopy. The crystals which were constructed with wafer-like laminations linked together, formed rosette-like structures, or aggregated with each other. The main components were calcium phosphate with a small amount of Mg under energy-dispersive X-ray microanalysis. The crystals were frequently coexistent with Mg-containing whitlockite (WH) while no WH crystals were observed in the early calculus; thereby, the pH range of the formation sites might be lower than that of WH crystals.

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To determine the degree of misarticulation in cleft palate patients undergoing prosthetic therapy, static palatography was used to identify contact patterns of tongue-to-palate and tongue-to-teeth movements during the production of sounds.
To accomplish this, a black vinyl sheet, vacuum molded to cover the palate and the occlusal surface of the maxillary teeth and coated with a white, alginate powder, was inserted into the mouth of the tested subject. Then, the subject was asked to pronounce a certain sound, and as the sound was produced, the movements of the tongue wet the powdered vinyl surface, thereby providing a palatogram of that sound. After taking 5 palatograms of each sound, the samples were averaged by an image processor.
The palatograms of each sound were then compared with palatograms of the same sound produced by normal subjects and evaluated for excessive or insufficient tongue contact with the palate and/or the dental arch in the production of phonemes. Aberrations in the palatogram pattern were graded on the basis of a numerical scale, with zero representing the least aberrant pattern and five representing the most aberrant pattern.
This palatographic method was used to evaluate speech in 5 cleft palate patients at three stages that follow : stage A, prior to the start of prosthetic treatment ; stage B, while wearing temporary dentures ; and at stage C, while wearing the final dental prostheses.
An analysis of these palatograms revealed that patterns indicating an abnormality were very apparent at stage A, particularly on pronunciation of the sounds /sa, ∫i, ta/, but, less so at stage B, and the patterns almost approximated normal patterns at stage C.

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Change in the structure of the elastic fibers of the submandibular and the sublingual glands were investigated histologically by using Sprague-Dawley rats aged 0 day to 78 weeks. These samples were stained with Lithion-carmin for nucleus staining and Weigert's resorcin-fuchsin for elastic fiber staining. All stained sections were observed under a transmitted light microscope. Elastase treatment was performed to confirm the existence of the elastic fiber.
Among the acini of the submandibular and sublingual glands, the slight thin elastic fibers invaded from the interlobular connective tissue were observed in 1 to 78 weeks-aged rats. The fibers were not observed at the intercalated ducts of both glands. The elastic fibers around the striated ducts first appeared in the submandibular gland on 9 weeks and in the sublingual gland on 1 week after birth. The fibers were observed clearly in the sublingual gland rather than in the submandibular gland. The elastic fibers around the interlobular excretory ducts were revealed in the submandibular and the sublingual glands on 1 week after birth. The number of the fibers increased in the sublingual gland from 5 weeks and in the submandibular gland from 26 weeks after birth. The elastic fibers around the striated and the interlobular excretory ducts appeared early in the sublingual gland earlier than in the submandibular gland. In the extralobular large ducts, the fibers revealed in the submandibular gland from 1 week and in the sublingual gland from 0 day after birth. The numerous elastic fibers were observed in both glands from 3 to 78 weeks after birth. There was an increase in the elastic fibers by aging in the submandibular and the sub-lingual glands. The structure of the elastic fibers showed the various shapes ; a straight line, curve, granulation, meandering, undulation, coil, ramification and bundle.

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We evaluated the association between the amount of gingival crevicular fluid (GCF) and activities of contained enzymes (LDH, LDH isozyme, alkaline phosphatase, β-glucuronidase, and arylsulfatase) in the patients with periodontitis. In addition, gingivitis was experimentally induced, and serial changes in clinical parameters (plaque index, gingival index, probing depth, and tooth mobility), the amount of GCF, and each enzyme activity were evaluated.
1. In the patients with periodontitis, a positive correlation was observed between the periotron unit and LDH activity as well as β-glucuronidase activity.
2. In the subjects with experimental gingivitis, the plaque index, gingival index, and the probing depth increased with time. The amount of GCF also increased until 3 weeks after the induction of gingivitis but decreased after 4 weeks.
3. In the patients with periodontitis, LDH₅ accounted for 50% of LDH isozyme. In the subjects with experimental gingivitis, the LDH₅ fraction appeared after 2 weeks.
4. In the subjects with experimental gingivitis, LDH activity increased after 1 week, decreased after 2 weeks, and increased again after 3 and 4 weeks. Alkaline phosphatase activity markedly increased after 1 week and decreased with time after 2 weeks or more.

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The purpose of present study was to determine the arrangement of collagen fibrils organizing bone matrix. The materials were diaphyses of long bones (humerus, radias, femurs and tibias), bodies of ribs and parietal bones of 3 year-old mature crab-eating monkeys. After fixation, the fibrous layers of ectoperiosteum were tore from bones. Specimens were treated by 1% trypin solution to digest both osteoblasts and amorphous organic matrix, and examined by high resolution scanning electron microscope.
The results we examined were as follows :
(1) On the surface of diaphyses of long bones, the bodies of ribs and parietal bones, collagen fibrils were organized into bundles. These bundles were 0.7-1μm in diameter.
(2) Many bone canaliculi were opened between collagen fibril bundles. Parts of bundles removed to neighbor bundles around bone canaliculi.
(3) At the part where superficial collagen fibril bundles were comparatively sparse, different arranged bundles were recognized between the superficial bundles.
(4) The surface, which was barely uneven, was dotted with the overlapping area of different arranged bundles.
(5) At the limited uneven area, the arrangement of collagen fibril bundles were irregularly running, and crossing each other. The bone canaliculi between bundles were round in shape.
(6) At the surface of parietal bone, bundles were running from parietal tuberosity to all directions.

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The antibacterial effect restorative materials is important for obtaining good prognosis. The purpose of this study was to evaluate the antibacterial effect of trial composite resins which were made with Clearfil SC II and antibacterial powder as a filler. Four kinds of antibacterial powder were used : two kinds of Cellewall; far infrared radiating ceramic materials YYT 1 and YYT 1A, Bactekiller; antibacterial zeolite and Zeomic; zeolite with antibacterial ion were mixed with Clearfil SC II at the content of 5, 10, 15, 20, 30, 40, 50 wt %. Cariogenic bacteria Streptococcus mutans Ingbritt, was used in this experiment. Disks were placed in petri dishes and the width of inhibitory zone was evaluated after 24 hours. In order to evaluate the effect of saline solution, the disks were stored in saline solution for 24 and 48 hours and the inhibitory zone were also evaluated same condition. The conclusion is that the new composite resins containing Zeomic had a strong antibacterial effect against S. mutans and this effect of Zeomic was not reduced after storage in saline solution.

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Ameloblastic fibro-odontoma is a rare odontogenic tumor. We reported a case of ameloblastic fibro-odontoma arising in the left mandible. A 12-year-old girl was referred to our department for examination of uneruption of left lower first molar and a swelling of left mandibular region. The panoramic radiograph revealed impacted first and second molars in and adjacent to the lesion mixed with radiolucent and radiopaque ones. The tumor was surgically resected under general anesthesia. Histopathological diagnosis was an ameloblastic fibro-odontoma. There is no evidence of recurrence in the patient 2 years after the operation.

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