A study of the predominant subgingival microflora was carried out in 24 periodontitis patients, 18 to 60 years of age, in Santo Domingo, Dominican Republic. Paper point sampling, transport in VMGA III, and conventional microbiological techniques were utilized. Direct microscopic examination revealed that cocci and nonmotile organisms made up 85% of the total organisms and spirochetes as little as 3%. Nonselective culturing showed Gram‐negative organisms to constitute 53% of total isolates. Fusobacterium nucleatum averaged 15%, black‐pigmented anaerobes 7%, and Peptostreptococcus micros 10% of the cultivable microflora. Enteric rods and acinetobacter species were recovered from 16 patients and comprised 23% of the cultivable flora. Enterobacter cloacae occurred in 8 patients, Klebsiella oxytoca in 3 patients, and 7 other species in 10 patients. Parallel studies have found a significantly lower prevalence of enteric rods in advanced periodontitis patients in the USA. In conclusion, fewer spirochetes and markedly more enteric rods seem to inhabit adult periodontitis lesions in Santo Domingo patients compared to those in USA. High levels of subgingival enteric rods in periodontitis patients in Santo Domingo may have important prophylactic and therapeutic implications. J Periodontol 1991; 62:543–547.

Summary-Althoughlinear enamel hypoplasia is commonly seen in children of malnourished communities throughout the world, the aetiology is undetermined. This study attempted to explore the distribution of this enamel defect in 429 Guatemalan children (ages 683 months) from four rural villages. The prevalence ranged from 18 to 24 per cent in three villages to 62 per cent in the fourth. The prevalence did not increase with age. suggesting caries was not an aetiologic factor. Protein supplement made available to pregnant mothers and children did not appear to reduce the occurrence of the lesion in children. Relatively fewer children manifested the lesion when born in the latter part of the year. No sex differences were observed. Siblings ofchildren with the lesion had a prevalence significantly greater than the total study population. suggesting that factors operating at the family level enhance the occurrence of the hqpoplastic lesion in children.

Guatemalan children with anterior linear enamel hypoplasia (LEH) had a significantly greater caries experience in posterior dentition than their peers who did not have anterior LEH. The findings suggest that the synergistic mechanism of undernutrition and infection, which may underlie the occurrence of anterior LEH, may also predispose clinically normal appearing deciduous molars to an excessive caries attack equal to that observed in the grossly hypoplastic anterior teeth. The nutritional implications merit further investigation.

This paper presents a preliminary approach to the study of the oral manifestations of HIV infections in the region of the Americans. A general description of the lesions encountered is provided together with a review of the prevalence of the different manifestations in some countries of the Americas. Oral candidiasis was the most common oral lesion identified. Among oral candidiasis lesions differences were noted in relation to the frequency of the clinical forms seen. Hairy leukoplakia was the second most frequent lesion in almost all studies, with the exception the Peruvian study, where the most prevalent oral condition was xerostomia. The numbers of cases of HIV-gingivitis and HIV-periodontitis found in the countries of the Americas were lower than the cases in USA. Other oral manifestations of HIV infections seen were: Kaposi's sarcoma, oral erythema, labial herpetic infection. It is concluded that still more studies are needed, oral health professionals need additional training in the detection and treatment of lesions, and information needs to be systematized and standardized such that it is possible to make accurate comparisons among regions and countries. Recommendations are included to improve this situation.

A study of 528 Guatemalan children indicated that caries prevalence in the deciduous dentition was twice as great as but in the permanent dentition was similar to that for US white children. This is a repeated observation for children of some preindustrial societies. Caries experience was significantly greater in boys. Until 4 years of age, caries attack was greater in the anterior segment of the oral cavity; linear enamel hypoplasia was a predisposing factor.