[Application of different doses of dexmedetomidine and midazolam in dental implant surgery].

OBJECTIVE: To compare the sedative effects of different doses of dexmedetomidine (DEX) and midazolam (MDZ) in dental implant surgery:

METHODS: Sixty patients undergoing dental implantation were selected and divided randomly into six groups (10 in each group). In group 1 (G1), a highdose of MDZ alone was administered intravenously. In group 2 (G2), a relatively low dose of MDZ and DEX was administered intravenously. In group 3 (G3), a highdose of MDZ and DEX was administered intravenously. In group 4 (G4), a lowdose of MDZ and a highdose of DEX were administered. In group 5(G5), a highdose of MDZ and a low dose of DEX were administered. In group 6 (G6), a highdose of DEX alone was administered intravenously. Blood pressure (BP), heart rate (HR), and arterial oxygen saturation values were measured. Sedation was assessed by determining the Ramsay sedation scores(RSS) during infiltration anesthesia (T1), incision (T2), cutting (T3), and suturing (T4). Before discharging from the hospital, patients were asked if they remembered the T1 to T4 procedures. The visual analogue scale (VAS) and the degree of patient satisfaction were assessed at the same time.

RESULTS: In T1 to T4, the systolic blood pressure (SBP) in G3 was the lowest and was significantly different from that in G1 and G2 (P < 0.05). In G1, the SBP was higher than that in G6 at the T3 and T4 points (P < 0.05). HR was below the preoperative (P < 0.05) in the G3 only. RSS was the lowest in G1 during the whole procedure. In G2, most patients obtained scores of 2-3. In G3, sedation was deeper, had more cases ofup to 5. In G4, most patients obtained scores of 3-4. In G5, some patients had a score of up to 5. The RSS in G6 was lower than that in G3 and G4 or G5 in T1 to T2, closer to G4 in T2. An evaluation of the VAS and the degree of patient satisfaction did not show any differences among the groups.

CONCLUSION: The combination of DEX and MDZ is superior to a single intravenous injection. Low-dose MDZ combined with high-dose DEX achieved the highest quality of sedation in this study.