Pilar Gándara-Vila

Alveolar distraction before insertion of dental implants in the posterior mandible

We investigated the efficacy of alveolar distraction for reducing crown height:implant length ratio in the posterior mandible. Ten alveolar distractions were done in seven patients. The pre-distraction ratio of required crown height to bone height available for implantation was in all cases > or =1. Two implants were placed in each distracted area (total 20 implants). Before distraction, the mean (SD) predicted crown height was 12.8 (2.1) mm; mean bone height available for implantation was 7.8 (1.5) mm. After distraction and insertion of implants, mean crown height was 8.1 (1.9) mm, and mean implant length was 11.3 (1.9) mm. Before distraction, the mean required crown height:available bone height ratio was 1.7 (0.3); after distraction and insertion of implants, the mean crown:implant ratio was 0.7 (0.2) (P<0.0005). Alveolar distraction is effective for increasing the height of the alveolar ridge in the posterior mandibular region, and should be considered when the height of the predicted crown that is required is greater than or equal to the maximum height of bone available for implantation.

Exfoliative cytology for diagnosing oral cancer

Abstract Exfoliative cytology is a minimally invasive technique for obtaining oral cell specimens from patients for diagnostic purposes. Classical applications of oral cytology studies, such as oral candidiasis, have been extended to include oral precancerous and cancerous lesions. A number of analytical methods are available for studying cytology specimens. The development of molecular analysis techniques, the oral cancer etiopathogenic process, and improvements in liquid-based exfoliative cytology are leading to renewed interest in exfoliative cytology. Results sometimes are disputed, so the aim of our review was to clarify the applicability of exfoliative cytology to the diagnosis of oral precancerous and cancerous lesions.

Applications of OralCDx ® methodology in the diagnosis of oral leukoplakia

Objective: We aim to evaluate the effectiveness of the brush biopsy technique using OralCDx ® (OralScan Laboratories Inc., Suffern, NY) as a new method for early diagnosis and control of a “potentially malignant disorder” such as oral leukoplakia. Design of the study: We performed a study in which samples were taken using OralCDx ® on 24 patients who visited the Master of Oral Medicine, Oral Surgery and Implantology of the University of Santiago de Compostela between February 2009 and May 2010. These patients presented clinical and histological lesions that were consistent with oral leukoplakia. We evaluated the relationship between the keratinization degree of the lesions and cell representation; the diagnosis obtained through OralCDx ® and biopsies; and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Results: 50% of patients were men and 50% women with an average age of 62.38 years. The Kappa coefficient relating keratinization of lesions and cell representation was 0.33, the OralCDx ® - biopsy diagnostic rate reached a Kappa value of 0.66, recording 72.7%,sensitivity and 92.3% specificity, PPV was 88.8%, while NPV reached 80%. Conclusions: cytology sampling with OralCDx ® showed high sensitivity and specificity values, which make it a good tool for monitoring oral leukoplakia, but nowadays the most reliable method that allows us to confirm the exact diagnosis of the lesions and their anatomical and pathological characteristics still is conventional biopsy using a surgical scalpel. Key words: OralCDx®, brush biopsy, oral leukoplakia.

Comparison of three sampling instruments, Cytobrush, Curette and OralCDx, for liquid-based cytology of the oral mucosa

Abstract Exfoliative cytology of the oral cavity is a simple and noninvasive technique that permits the study of epithelial cells. Liquid-based cytology is an auxiliary diagnostic tool for improving the specificity and sensitivity of conventional cytology. The objective of our study was to compare the quality of normal oral mucosa cytology samples obtained using three different instruments, Cytobrush®, dermatological curette and Oral CDx® for liquid-based cytology. One hundred four cytological samples of oral cavity were analyzed. Samples were obtained from healthy volunteer subjects using all three instruments. The clinical and demographic variables were age, sex and smoking habits. We analyzed cellularity, quality of the preparation and types of cells in the samples. All preparations showed appropriate preparation quality. In all smears analyzed, cells were distributed uniformly and showed no mucus, bleeding, inflammatory exudate or artifacts. We found no correlation between the average number of cells and the type of instrument. The samples generally consisted of two types of cells: superficial and intermediate. No differences were found among the cytological preparations of these three instruments. We did not observe basal cells in any of the samples analyzed.

Survival study of leukoplakia malignant transformation in a region of northern Spain

Background Oral leukoplakia is the most common potentially malignant disorder (PMD) of the oral cavity. The objectives of this study are to determine the clinicopathologic features in a group of patients with oral leukoplakia of Northern Spain (Galicia), determining the factors associated to clinical risk and analyzing the malignant transformation of these patients. Material and Methods We included 85 patients. We recorded sex and age, habits like alcohol and tobacco, size, clinical appearance, site, number of lesions, and presence or absence of dysplasia. We assess the association between risk factors and transformation and developed a logistic regression analysis. Finally we used the Kaplan-Meier and log-rank test for the survival analysis. Results 7 patients (8.2%) had malignant transformation. The mean follow-up of the patients was 4.13 years versus 5.58 years of those who developed carcinoma. Only location and initial dysplasia have a statistically significant relationship with malignant transformation, but when applied the long rank test only the presence of dysplasia remains statistically significant(P<0,026). Oral Cancer Free Survival was 81.9% (0.150) at 11 years for the group without dysplasia. Conclusions We found that the presence of dysplasia is the only risk factor that is statistically related to the development of a carcinoma. Key words:Leukoplakia, oral cancer and oral precancer, follow-up, malignant transformation.

Human Papillomavirus-Related Oral Cancer: Knowledge and Awareness Among Spanish Dental Students

Human papillomavirus (HPV) infections are responsible for a significant part of the global burden of cancer. Epidemiologic studies have shown increasing trends of HPV-related oral cancers worldwide. Dental professionals need comprehensive up-to-date HPV-related information to be able to provide correct advice to their patients. The aim of this paper is to describe knowledge and awareness levels of dental students from Spain on HPV infection, HPV vaccination, oral cancer prevention, and HPV-related oropharyngeal cancer. A survey was distributed to 240 dental students, of which 158 returned it. Most students reported not been vaccinated against HPV (n = 81, 51.3%) and believed that HPV infection was linked to oropharyngeal cancer (75%). Overall, advanced students showed better knowledge, attitudes, and perceptions regarding this issue while novice students showed relevant shortcomings. However, their attitudes in relation to the diagnosis of oral cancer were adequate. These results suggest that there are important HPV-related knowledge deficits among Spanish dental students, which hinders their interventions in oropharyngeal primary prevention efforts. Findings of this study suggest the inclusion and standardization of HPV-related educational information to the dental curriculum.