An explication of the relationship between the presence or absence of enough eruptive space for permanent successors and the growth conditions of their roots at the time of normal replacement is a very important matter, which enables us to learn what kind of an arch to be expected. Among factors having important bearings on the formation of buccal or lateral segment of permanent dentition are the degrees of growth of different gnathofacial portions, particularly that of the dental arch and those of individual teeth, harmony of these, presence of absence of the leeway sapce, sequence of successive replacement, occlusal states of deciduous and permanent dentitions, terminal plane in particular, and eruptive period of the second molar.
NODA [5] studied changes in the length of buccal arch in relation to the final formation of buccal segment based on serial plaster models. IWASAWA [6] investigated time distances between the shedding of decidous teeth and the eruption of permanent successors, that is, the relationship between periods of exchange and incidence of malocclusion. KAWASHIMA [7] and SATO [8] respectively studied the relation of eruptive sequence to buccal segment of the permanent dentition.
On the strength of the previous findings [1, 2, 3, 4], the authors came to believe that the formative speed and amount of root immediately before and after the eruption of 5 exert a most potent influence on the ultimate completion of permanent dentition. according to GRØN [9], the eruptive condition of a tooth is more closely related to the formative degree of root rather than postnatal age or bone age of an individual and when a root has been formed by 3/4, it erupts clinically. In a similar vein, FLANNING [10] maintains that on the whole if a root has been formed by 2/3, that tooth will clinically erupt.
HAAVIKKO [11], who distinguishes the time of bone eruption from clinical eruption, gives differences of 1/2 for bone eruption and 3/4 for clinical eruption allowing for variations among different teeth.
According to the present study, standard R/C at bone eruption of 3 is 0.96 for boys and 0.98 for girls respectively (Tables 2, 3). However, with cases in which a premature loss ultimately led to normal dentition the numerical value for boys is 1.07 and 1.02 for girls. A statistical difference (α=0.01) was seen between the girl group of normal replacement and that of premature losses which eventually resulted in normal dentition.
From all these findings, it is possible to conclude that the cases of 5 which had formed their roots sufficiently large at bone eruption were so strong that they pushed the neighboring 4 and 6 aside to result in normal dentition, despite the fact that there was a premature loss of E of one kind or another. When R/C at the minimum space of 5 is compared between the sexes, only 2/3 (1.28) had been formed of 1.92 of the complete root formation on the part of 20 decidous teeth in boys. On the other hand, 14 teeth out of 16 had formed 2/3 (1.22) of 1.82 at complete root formation in girls.
The cases where the premature loss of E resulted in some kind of anomalous dentition are 0.57 in boys and 0.62 in girls respectively, as compared with 0.96 in boys and 0.81 in girls of the cases where the premature loss of E turned out to be normal dentition of 5. The reason for this is obvious in that the eruptive space has been much restricted (see Fig. 3).
These observations show that, even in individuals in whom some kind of anomaly exists at the period of successive replacement, normal dentition will be possible when there is a mesio-distal eruptive space for 3 corresponding to about 2/3 of the crown width. It may be added in this connection that there were several cases where quite restricted eruptive spaces led to normal dentition (Nos. 1, 14, 17 of Table 4 and No. 1 of Table 5 are the cases in point). When these cases are minutely examined, it is found that their roots took on an

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L-carnosine (βalanyl 1-histidine), used in the form of a dental cone in the amount of 5mg per root, proved successful in relieving pains associated with dental extraction, as endorsed by the inhibition of edemata and postoperative pain complaints.
This antiinflammatory effect of 1-carnosine is believed to be found in the promotion of defense mechanism inherent in the vital tissues. The effective dosage of the present clinical study corresponds to 1/35 of what is usually contained in the vital tissue.

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An effective dose of 1-carnosine (β-alanyl-1-histidine) for the restoration of inflammatory tissues (by formalin filter method) is known to be 8.8 μmol/100g rat ip. In the present paper, an application of this potent effect to the decubital ulcer is discussed. By spraying minute powder of 1 to 3g carnosine on an ulcerous wound, the necrotic layer is made to fall off and, through the formation of new granulations, the wound will become gradually cicatrized from the periphery.
Carnosine, when used in the form of spray in an amount of 1 to 3g daily, proved quite beneficial to 5 patients of the decubital ulcers of varying degree. When a case is light enough without any necrotic layer, the formation of fresh granulations took place in about 2 weeks, reaching a complete cure. The physiologic significance of carnosine in the repair of inflamed tissues is now being explicated. That carnosine corresponding to 1/35 of what is usually contained in a vital body is sufficient to repair inflamed tissues, appears to indicate that carnosine is an important chemical mediator playing a major role in this healing process.
Our biochemical knowledge of carnosine alone will not solve the granular promotive mechanism on the part of carnosine and much future research is indicated in this direction.
At the present state of our knowledge, it may be concluded that, along with cortisone, carnosine is significant in that it is a co-factor in the vital defense mechanism.

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