The results are in contradiction with the established hypothesis that absence of teeth outside the cleft area of the maxilla is due to an unknown congenital factor. On the contrary, the findings support the hypothesis that surgery for the closure of the hard palate in early childhood is the most important etiological factor for the absence of teeth outside the cleft area in the early operated cleft patient. The superficial position of the tooth germs (at the time of the palatal surgery), especially those of the premolars, supports this hypothesis.
Background Ameloblastoma is a common benign odontogenic tumor of the jaw with a local invasive and highly destructive behavior and can develop in any age, with peak prevalence in 3rd-4th decade. Ameloblastoma can be divided into six histological types: follicular, plexiform, acanthomatous, desmoplastic, granular, and basal cell. Matrix metalloproteinase-9 (MMP-9) (92-kD gelatinase/ type IV collagenases = gelatinase B) is involved in bone resorption by degradation of extracellular matrix and osteoclasts recruitment. Recent studies have found that MMP-9 is expressed by ameloblastoma and has a role in ameloblastoma local invasiveness. Objective To analyze MMP-9 expression between different histological types of ameloblastoma. Material and Method Forty samples of ameloblastoma were collected through consecutive sampling and the MMP-9 expression was detected using immunohistochemistry. Result All samples showed positive MMP-9 expression with moderate to strong intensity. 82.4 % plexiform type and 83.3 % mixed type have strong immunoexpression, significantly different with follicular type with only 36.4 % (P \ 0.05). Conclusion Ameloblastoma plexiform and mixed type have higher MMP-9 expression than ameloblastoma follicular type. Different MMP-9 expression may contribute in different ameloblastoma biological behavior.
Objective
The purpose of this study was to investigate the possible absence of teeth in the postcanine region of the upper jaw of the unoperated adult cleft patient.
Method
The study was performed on 266 dental casts of fully unoperated adult cleft patients. The patients were divided into four groups according to the type of the cleft: unilateral cleft lip and alveolus, unilateral cleft lip and palate, bilateral cleft lip and alveolus, and bilateral cleft lip and palate.
Results
No absence of permanent teeth in the canine and postcanine area of the upper jaw could be found.
Conclusion
The results are in contradiction with the established hypothesis that absence of teeth outside the cleft area of the maxilla is due to an unknown congenital factor. On the contrary, the findings support the hypothesis that surgery for the closure of the hard palate in early childhood is the most important etiological factor for the absence of teeth outside the cleft area in the early operated cleft patient. The superficial position of the tooth germs (at the time of the palatal surgery), especially those of the premolars, supports this hypothesis.
In subjects with orofacial clefts, there is an unresolved controversy on the effect of congenital maxillary growth deficiency vs. the effect of surgical intervention on the outcome of treatment. Intrinsic growth impairment in subjects with orofacial clefts can be studied by comparing facial morphology of subjects with untreated cleft and unaffected individuals of the same ethnic background. Bilateral cleft lip and palate is the most severe and least prevalent form of the orofacial cleft. The aim of this study was to compare facial morphology in subjects with unrepaired complete bilateral clefts and unaffected controls using geometric morphometrics. Lateral cephalograms of 39 Indonesian subjects with unrepaired bilateral complete cleft lip and alveolus (mean age: 24 years), or unrepaired bilateral complete cleft lip, alveolus, and palate (mean age: 20.6 years) and 50 age and ethnically matched controls without a cleft (25 males, 25 females, mean age: 21.2 years) were digitized and traced and shape variability was explored using principal component analysis, while differences between groups and genders were evaluated with canonical variate analysis. Individuals with clefts had a more pronounced premaxilla than controls. Principal component analysis showed that facial variation in subjects with clefts occurred in the anteroposterior direction, whereas in controls it was mostly in the vertical direction. Regression analysis with group, sex, and age as covariates and principal components from 1 to 6 as dependent variables demonstrated a very limited effect of the covariates on the facial shape variability (only 11.6% of the variability was explained by the model). Differences between cleft and non‐cleft subjects in the direction of facial variability suggest that individuals with bilateral clefts can have an intrinsic growth impairment affecting facial morphology later in life.
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