Biomechanical and histomorphometric analysis of osseodensification drilling versus conventional technique: a systematic review and meta-analysis.

OBJECTIVES: This systematic review aimed to search the literature for the answer to the following questions. In human studies: Does the osseodensification technique increase the resonance frequency analysis given in implant stability quotient value and the insertion torque value compared to the conventional technique? In animal studies: Does the osseodensification technique increase implant stability quotient, bone-to-implant contact, and bone area fraction occupancy values over the conventional technique? DATA SOURCES: A search for studies was carried out in eight databases until August 2021. Out of the 447 publications found, 11 were included. RESULTS: In human studies, osseodensification technique showed better results for implant stability quotient values with a summarized median difference of 8.57. As for secondary stability, there was no significant difference, with summarized median difference of 4.49 in favor of the osseodensification technique. In animal studies, all results were favorable to the osseodensification technique. Regarding insertion torque, bone-to-implant contact, and bone area fraction occupancy between counterclockwise osseodensification technique vs conventional, the mean difference was 46.79 for insertion torque, 2.17 for bone-to-implant contact, and 2.11 for bone area fraction occupancy. High heterogeneity was observed between the studies. The risk of bias in humans was moderate in three studies and low in one; and in animal studies, four presented moderate risk, two low risk, and one high risk. The certainty of evidence ranged from low to moderate. CONCLUSION: The osseodensification technique showed improvement concerning the resonance frequency and the insertion torque value of implants in human studies. In addition, it increased the values of bone-to-implant contact, bone area fraction occupancy, and implant stability quotient in animal studies, when compared to the conventional technique.

Subjective versus objective, polymer bur-based selective carious tissue removal: 2-year randomized clinical trial.

OBJECTIVES: We aimed to compare subjective (S) selective carious tissue removal using hand instruments versus objective (O) removal using a self-limiting polymer bur in a single-blind cluster-randomized controlled superiority trial. METHODS: 115 children (aged 7-8 years) with ≥1 vital primary molar with a deep dentin lesion (>1/2 dentin depth) were included and randomized (60 S/55 O); all eligible molars in a child were treated identically (91 S/86 O). Cavities were prepared and carious tissue on pulpal walls selectively removed using hand instruments (S) or a self-limiting polymer bur (Polybur P1, Komet), followed by restoration using a glass hybrid material (Equia Forte, GC). Treatment time and satisfaction data have been reported in a 1-year-interim report. We here report on 2 year survival (tooth retained with or without further retreatments being needed, or tooth exfoliated), analyzed using multi-level Cox-regression analysis, as well as success (ART criteria 0/1, no pulpal complications, no re-intervention needed, or tooth extraction). RESULTS: 71 restorations in S and 65 in O were examined after a mean (SD, range) of 22 (11; 3-31) months, of which 50 S and 48 O restorations were successful and 70 S and 65 O survived. The majority of failures were restorative, not pulpal, and distribution of ART codes was not significant different between groups. Risk of failure was not significantly associated with the removal protocol (HR; 95 % CI: 0.95; 0.51-1.78), and also not age, sex or dental arch, while single surfaced restorations showed significantly lower hazard (0.14; 0.06-0.37). CONCLUSION: There was no significant difference in success or survival between objective and subjective carious tissue removal. CLINICAL SIGNIFICANCE: In primary teeth, subjective selective excavation had no disadvantage compared with objective excavation, which required a separate instrument (polymer-based bur) for carious tissue removal. Polymer-based burs may be particularly useful when standardized excavation is needed.