Surgical treatment modality for facial esthetics in an obstructive sleep apnea patient with protrusive upper lip and acute nasolabial angle.

For patients with severe obstructive sleep apnea syndrome (OSAS), maxillomandibular advancement (MMA) offers a good treatment option by physically expanding the skeletal framework. However, facial esthetics can be aggravated by MMA in patients with OSAS who have a normally positioned maxilla, a protrusive upper lip, and an acute nasolabial angle. Therefore, surgical treatment planning should be customized according to diverse skeletodental and soft-tissue patterns to produce a favorable change in facial esthetics and sleep function in patients with OSAS. In this case report, good treatment results were achieved in a young female patient with OSAS and skeletal Class II, a normally positioned maxilla, a protrusive upper lip, and acute nasolabial angle by impaction of the maxilla, autorotation/advancement of the mandible, and advancement of the chin. A customized flowchart for surgical treatment planning in OSAS that considers facial esthetics was suggested.

Angled-predrilling depth and mini-implant shape effects on the mechanical properties of self-drilling orthodontic mini-implants during the angled insertion procedure.

OBJECTIVE: To investigate the effects of orthodontic mini-implant (OMI) shape and angled-predrilling depth on the mechanical properties of OMIs during the angled insertion procedure. MATERIALS AND METHODS: A total of 30 OMIs (self-drilling type, 7 mm in length) were allocated into six groups according to the OMI shape (cylindrical or tapered) and angled-predrilling depth (control, 1.5-mm and 4.0-mm angled-predrilling; predrilled with 1-mm-diameter drill-bit), as follows: C-con, C-1.5, C-4.0, T-con, T-1.5, and T-4.0 groups (N  =  5 per group). The OMIs were installed at an angle of 60° in double-layer artificial bone blocks that simulated the cortical and cancellous bone (Sawbone(®)). Total insertion time (TIT), maximum insertion torque (MIT), total insertion energy (TIE), and inclination of the time-torque graph (INC) were measured. RESULTS: Within the same shape group, angled-predrilling had a shorter TIT than did the control (control vs 1.5; control vs 4.0; all P < .05). MIT and TIE decreased in the order of control, 1.5-mm, and 4.0-mm angled-predrilling (control vs 1.5; 1.5 vs 4.0; all P < .05), but INC increased from control to 1.5-mm angled-predrilling and decreased from 1.5-mm to 4.0-mm angled-predrilling within the same shape group (control vs 1.5, 1.5 vs 4.0; all P < .05). The MIT of the tapered group was greater than that of the cylindrical group (C-con vs T-con, C-1.5 vs T-1.5; all P < .05, C-4.0 vs T-4.0; P < .01). In the same angled-predrilling depth, no differences were observed in TIE between the cylindrical and tapered groups (C-1.5 vs T-1.5, C-4.0 vs T-4.0; all P > .05). CONCLUSIONS: In angled-predrilling insertion of OMIs into thick cortical bone, tapered OMIs might be a better choice than cylindrical OMIs for increasing primary stability because of higher MIT and similar TIE values.

Effects of predrilling depth and implant shape on the mechanical properties of orthodontic mini-implants during the insertion procedure.

OBJECTIVE: To investigate the effects of orthodontic mini-implant (OMI) shape and predrilling depth on the mechanical properties of OMIs during the insertion procedure. MATERIALS AND METHODS: A total of 30 OMIs (self-drilling type, 7 mm in length; Biomaterials Korea Inc) were allocated into six groups according to OMI shape (cylindrical and tapered type) and pre-drilling depth (control, 1.5-mm and 3.0-mm predrilling; predrilled with a drill-bit [1 mm in diameter]): C-con, C-1.5, C-3.0, T-con, T-1.5, and T-3.0 groups (N  =  5 per group). The OMIs were installed in artificial bone blocks with two layers that simulated the cortical and cancellous bone (Sawbone®, Pacific Research Laboratories Inc). Total insertion time (TIT), maximum insertion torque (MIT), total insertion energy (TIE), and inclination of the time-torque graph (INC) were measured. RESULTS: Within the same shape group, although predrilling groups exhibited shorter TIT than control groups (control vs 1.5; control vs 3.0; all P < .05), there was no difference in TIT between 1.5-mm and 3.0-mm predrilling groups. MIT and TIE decreased in the order of control, 1.5-mm predrilling, and 3.0-mm predrilling (control vs 1.5; 1.5 vs 3.0; all P < .05), but INC revealed a pattern of increase from control to 1.5-mm predrilling and of decrease from 1.5-mm predrilling to 3.0-mm predrilling within the same shape group (control vs 1.5, 1.5 vs 3.0, all P < .05). The MIT and INC of C-con were smaller and less steep than those of T-con (P < .01 and P < .05, respectively). In the same predrilling depth, no differences were observed in MIT, INC, and TIE between cylindrical and tapered groups. CONCLUSION: In cases of thick cortical bone, predrilling might be an effective tool for reducing microdamage without compromising OMI stability.