Tooth Extraction

We have carried out a cross-sectional analysis on 1020 Caucasian participants (365 men and 655 women) between the ages of 18 and 80 years old recruited in the Obesity, Nutrition & Information and Communication Technologies (OBENUTIC) study. OBENUTIC [52 (link)] is a case-control study carried out in the general population of the Valencia Region (East Mediterranean coast of Spain). Cases were individuals with obesity (body mass inde × (BMI) ≥ 30 kg/m²) and the controls were non-obese individuals (BMI < 30 kg/m²) recruited from the same location and without pairing for age and sex. Cases and controls were apparently healthy individuals recruited through advertisements in shopping malls, housewives’ associations, cultural associations and other types of groups from the general population, public and private institutions, educational centres, home contacts and a few primary health care centres. The exclusion criteria were being pregnant or breast-feeding, suffering from some type of infectious/contagious disease, invalidating physical or psychological diseases, cancer diagnosis, thyroid alterations, Cushing disease, have conditions that could alter gustatory functions (e.g., tooth extraction), high alcohol intake or the consumption of other drugs.
Participants visited the Genetic and Molecular Epidemiology Unit and the sensory research laboratory at Department of Preventive Medicine and Public Health at the University of Valencia, Valencia, on two-three separate sessions within a week. At the first session, participants completed a health and demographic questionnaire and their anthropometric parameters and blood pressure were measured as indicated. Participants also completed lifestyle questionnaires and the food preference questionnaires and were scheduled for a blood venepuncture in fasting conditions for biochemical analysis and DNA isolation. In addition, participants were scheduled for the taste perception tests under standardized conditions. Initially, the OBENUTIC study began in 2007 by only including the bitter taste perception tests but later, the project was completed by including the perception tests for the other tastes. In this study, we analysed 1020 participants (365 men and 655 women) for those who consecutively had the complete data available for the perception tests of bitter, sweet, sour, salty and umami tastes. Participants provided written informed consent and study protocol and procedures were approved according to the ethical standards of the Helsinki Declaration and by the Human Research Ethics Committee of the University of Valencia, Valencia.

hPDLSCs were isolated from the periodontal tissue and hDPSCs from the dental pulp of noncarious third molars extracted for orthodontic purpose, as previously described [19 (link)]. Gingival tissues were collected during surgical gingival resection for the extraction of a supernumerary tooth or for orthodontic reasons. hGMSCs were detached after their spontaneous migration from tissue samples as reported by Soundara Rajan et al. [20 (link)]. All donors were in good general health and exempt from oral and systemic diseases. Cells were cultured using MSCGM-CD medium (mesenchymal stem cell growth medium chemically defined) (Lonza, Basel, Switzerland) and were maintained in an incubator at 37°C in a humidified atmosphere of 5% CO₂ in air. Cells were subcultured until P2 and P15. All experiments were performed in triplicate. Cells derived from each donor have been used separately.

Study participants were three patients (two female and one male patient; mean age, 51 years) with chief complaint of severe lower anterior teeth mobility and severe periodontal compromission hindering any periodontal or conservative treatment. As control case, a patient (#1) referred with chief complaint due to lower third molar pericoronitis and indication for surgical extraction was recruited.
The exclusion criteria for this study were antibiotic therapy administered up to 3 months before tooth extraction, systemic diseases, and pregnancy. Another exclusion criterium was evaluating that periodontal pockets could not reach the apical root segment. Moreover, inclusion criteria were teeth affected by EPL without clinically and radiographically identified caries lesions, cracks/fractures and/or restorations.
The patients involved in the research signed a formal written informed consent form.
EPL diagnosis was performed with periodontal probing that evaluate an average clinical attachment loss ≥5 mm on all root’s surfaces and radiographic analyses on periapical bidimensional radiographies using paralleling technique confirming bone loss extending to mid-third of root and beyond; moreover, periapical radiolucency was not observed. None of these teeth presented periodontal pockets reaching the apex. Teeth presented Grade 2 mobility with percussion and palpation sensitivity. In addition, thermal and electric pulp sensibility tests were performed returning non-responsivity and thus confirming pulpar necrosis. Thermal pulp test was performed with a #2 cotton pellet sprayed and fully saturated with 1,1,1,2-tetrafluoroethane and placed at the middle third of the buccal tooth’s surface of the clinical crown for at least 20 s. Cold pulp testing was selected as pulp sensibility test which is able to evaluate vital (specificity = 0.84) and non-vital (sensitivity = 0.87) teeth [10–12 (link)]. No other EPL signs/symptoms (sinus tract, spontaneous pain, periapical radiolucency, suppuration) were observed.
Moreover, on intraoral inspection using loupes for magnification 4.0× and radiographic evaluation, the teeth did not present clinically identified caries lesions, cracks, fractures nor previous conservative restorations. The final diagnosis for all teeth was of EPL without root damage of Grade 3, according to the classification from the American Academy of Periodontology criteria. The sampled teeth clinically appeared without defects, decay, or restorations and were affected by severe periodontitis (Stage IV) according to the classification of American Academy of Periodontology criteria [5 (link)]. Control sample consisted of an intact lower third molar without carious and periodontal pathologies, surgically extracted because affected by pericoronitis. All teeth affected by EPL were single-rooted (N = 5 lower incisors and N = 1 lower canine).
A total of 12 clinical samples of the study group were collected from periodontal (P) (n = 6) and endodontic (E) (n = 6) tissue samples of root canals from six intact teeth of three patients (P1 and E1 from patient #1, P2 to P5 and E2 to E5 from patient #2, and P6 and E6 from patient #3).
All teeth were single-rooted (lower incisors and lower canine).
The study was performed in agreement with the ethical guidelines of the Declaration of Helsinki laid down in the 1964 and its later amendments or comparable ethical standards. The Ethics Committee of Azienda Unità Sanitaria Locale of Bologna approved this study with authorization no. 844-2021-OSS-AUSLBO-21160-ID 3118-Parere CE-AVEC-ENDO-MICROBIOTA 09/2021.