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The prevalence of lower alveolar flat ridge among completely edentulous patients in Sulaimani

Cheman A.  AL-Jmoor, Faten Khalid Ali Al-Kadi & Jwan F. Abdulkareem

College of Dentistry, University of Sulaimani



Objectives: The aim of the present study is to investigate the prevalence of lower flat ridge among a sample of completely edentulous patients, and to correlate it with age, gender, the presence or absence of a previous denture and the period of complete edentulism.

Materials and Methods:
297 patients with lower flat ridge were included in the study. A questionnaire was used to record the data of each patient which include; the gender, the age of the patient, the presence or the absence of a previous denture, and the date of the last tooth extraction (the period of complete edentulism). The patients were informed that the recorded information was required for a research purpose, and it will be used in a survey, and their consents and agreements were taken verbally. All the collected data were checked and assessed by a prosthodontic specialist. The patients age were divided into four groups; (41-50 years), (51-60 years), (61-70 years), (more than 71 years). The period of complete edentulism were divided into two groups; (up to 5 years), and (more than 5 years). The data were correlated and descriptive statistic of tables, numbers and percentages along with Chi-Square, were used to analyze the data.

The results of the study showed that; 150 (50.505%) of the patients were males and 147 (49.494%) of the patients were females. The majority of the patients were from the age group (61-70) and (51-60) years in male and female respectively. No significant differences were found between gender and age group (P>0.05). The occurrence of the lower flat ridge was significantly higher in patients with previous dentures 184(61.952%) than those without dentures 113(38.047%) in both genders (P< 0.05). Finally, the results revealed that patients who were completely edentulous for up to five years had significantly higher numbers of lower flat ridge 178(59.932%) comparing to those who were completely edentulous for more than five years 119(40.067%).

The presence of a previous denture, the longevity period of complete edentulism, the age, and the gender of the patient has an effect on the resorption of the lower residual ridge, and on the height of the lower residual ridge.

Keywords: lower residual ridge, previous complete denture, complete edentulism


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