Jawbone quality classification in dental implant planning and placement studies. A scoping review.

Aim: Cone beam computed tomography has become an attractive method for implant planning. However, in most cases, not all the information is taken advantage of and often the radiographic evaluation of bone quality is based on subjective assessment by the individual clinician. Therefore, the aim of this study was to examine classifications of bone tissue characteristics and methods for assessing them in dental implant planning and placement studies. Materials and Methods: Three databases (Pubmed, Scopus, Web of Science) were searched using specific index terms: "Bone quality, bone quantity, bone density, cone-beam CT and cone-beam computed tomography". Three reviewers selected titles and analyzed abstracts according to inclusion and exclusion criteria. Some descriptions of bone tissue characteristics (bone quality, density, and quantity) used before or during dental implant placement were selected and categorized. Results: The search yielded 442 titles. A total of 32 articles were selected and read in full text. Seventeen articles were considered relevant. Different classification systems were found to evaluate bone tissue characteristics as well as different examination protocols. Thirteen publications included in this review reported on bone quality and quantity using the Lekholm and Zarb classification. However, only four studies implemented and/or proposed modifications of the Lekholm and Zarb system. Four other publications described bone quality according to different classification systems such as Misch, University of California Los Angeles (UCLA), or Trisi and Rao. The assessment methods were often briefly described (or not described at all in one publication). Of the articles analyzed, five presented observer performance, whereas three presented diagnostic accuracy of the assessment method. Conclusion: Currently, there are different classification systems applied to dental implant planning and placement, particularly regarding whether bone quality or quantity affects treatment outcomes. However, most authors have not validated the diagnostic accuracy and reproducibility of the classification used. Therefore, it is necessary to develop a classification system consistent with characteristics of bone tissue, taking into consideration an adequate description of bone tissue assessment methods, their diagnostic accuracy, and observer performance.

Effect of fibrin-rich plasma and collagen sponge on healing of the palatal mucosa.

Background: The purpose was to evaluate the variation in thickness and early healing of the donor area of the palate with the placement of a collagen sponge and the use of fibrin-rich plasma (L-PRF). Material and Methods: Thirty patients who required mucogingival surgery treatment were selected and distributed into 2 groups. After obtaining the free palate graft, L-PRF was placed in Group A, and a collagen sponge was placed in Group B. The healing process of the palate was evaluated at 24 hours and 7, 14, 21 and 28 days postsurgery. The thickness of the donor area (palate) was evaluated using an acrylic splint. These measurements were made before and 4 months after surgery. Results: In the collagen sponge group, less gain of the palatal mucosa was observed, with a mean difference of 0.1 ± 0.8 mm (CI: -0.341-0.518) (p=0.691), whereas in the fibrin-rich plasma group, a mean difference of 0.0 ± 0.5 mm (CI: -0.229-0.229) (p=0.934) was found; however, when comparing the gain of the palatal mucosa in both groups, no significant difference was observed (p=0.932). The healing index at 24 hours indicated the presence of clots, on Day 28 vascularisation and total epithelialisation (100.0%), and finally, the collagen sponge group on Day 14 presented 93.3% partial vascularisation of connective tissue and 33.3% L-PRF (p=0.001). Conclusions: There was no statistically significant difference in the thickness of the palatal mucosa after the use of L-PRF and the collagen sponge. Key words:Palate thickness, connective tissue graft, fibrin-rich plasma, collagen sponge, palate healing.

Evaluation of Buccal Bone Wall Thickness of Anterosuperior Teeth and Nasopalatine Duct Morphology in Cone Beam Computed Tomography of Patients Living at Different Altitudes: A Two-Year Retrospective Study.

AIM: To evaluate the buccal bone wall thickness of anterosuperior teeth and the dimension and morphology of the nasopalatine duct in cone beam computed tomography (CBCT) of patients treated in two cities at different altitudes. MATERIALS AND METHODS: In this retrospective analytical study, 79 CBCT scans were selected from a total of 347 in Juliaca, Peru (3824 m a.s.l.) and 171 CBCT scans were selected from a total of 622 in Lima, Peru (154 m a.s.l.). The buccal bone wall thickness of anterosuperior teeth was measured at 1 mm, 3 mm, and 5 mm from the alveolar crest. For the nasopalatine duct, its length and diameter were measured, and its anatomical shape was determined in coronal view. Descriptive statistical data such as mean and standard deviation were used, and Mann-Whitney U test was used for bivariate analysis. RESULTS: When comparing the CBCT scans from both cities, significant differences were observed in buccal bone wall thickness at 3 mm and 5 mm from the alveolar crest (P < 0.01 and P < 0.01, respectively); for men, at 1 mm and 3 mm (P = 0.04 and P = 0.04); for the age group from 33 to 47 years, at 3 mm and 5 mm (P < 0.01 and P < 0.01); and for the age group from 48 to 77 years, at 1 mm (P = 0.02). Regarding the nasopalatine duct, significant differences were observed in women in relation to length and nasal opening diameter (P < 0.01 and P < 0.01) and for men, in length (P < 0.01); for the age group from 18 to 32 years, in all three levels (P < 0.01); for the age group from 33 to 47 years, in length and diameter of the oral opening (P < 0.01 and P < 0.01); and for the age group from 48 to 77 years, in length and diameter of the nasal opening (P < 0.01 and P < 0.01). The most frequent nasopalatine duct shape was a single canal with more than 66% of cases, according to sex and age group. CONCLUSION: Patients living at different altitudes presented significant differences in buccal bone wall thickness according to sex and age; however, there were no differences related to dental inclination. Significant differences were found in the length and diameter of the nasopalatine duct at the nasal opening. In addition, the most frequent shape of the nasopalatine duct was the simple canal.