Change in taste sensation after orthognathic surgery.

OBJECTIVE: The objective of this study was to evaluate the effect of orthognathic surgery on taste sensation. MATERIALS AND METHODS: Thirty-five patients scheduled to undergo Le Fort I osteotomy (LFIO), sagittal split ramus osteotomy (SSRO), and bimaxillary surgery (BMS) were evaluated by administering localized and whole-mouth taste tests preoperatively and postoperatively at months 1, 3, and 6. The patients were asked to identify the quality of four basic tastes applied to six locations on the palate and tongue and to rate the taste intensities they perceived. Taste recognition thresholds and taste intesity scores were evaluted according to operation groups and follow-ups. RESULTS: There were significant decreases in the quinine HCl recognition thresholds at the postoperative follow-ups compared to the preoperative in LFIO patients (p = 0.043). There were significant decreases in sucrose taste intensity scores in the right posterolateral part of the tongue at months 3 and 6 compared to preoperative in SSRO patients (p = 0.046), and significant increases in quinine HCL taste intensity scores in the right and left anterior parts of the tongue at month 6 compared to preoperative in LFIO patients (p < 0.05). CONCLUSION: Taste perception is affected due to potential damage to the chemosensory nerves during orthognathic surgical procedures. Generally, non-significant alterations have been observed in taste perception after orthognathic surgery, except for significant alterations in bitter and sweet taste perceptions. CLINICAL RELEVANCE: Maxillofacial surgeons should be aware of taste perception change after orthognathic surgery procedures and patients should be informed accordingly. THE TRIAL REGISTRATION NUMBER (TRN): NCT06103422/Date of registration: 10.17.2023 (retrospectively registered).

The Influence of the Hourglass Form of the Neck on Perceptions of Frontal Esthetics.

The purpose of this investigation was to evaluate the effect of the neck concavity angle (NCA) on different occupational groups' perceptions of frontal esthetics. An online survey was developed using Google Forms and sent to the observers through WhatsApp. Male and female frontal silhouettes were created, and NCAs that comprise the hourglass form of the neck were altered in 5 degrees increments from 120 degrees to 170 degrees. Observers were asked to score the images using 0 to 10 numerical rating scale. In all, 279 observers (97 orthodontists, 92 oral-maxillofacial surgeons, and 90 laypeople) participated in this study. For the male and female silhouettes, an NCA of 145 degrees was perceived as the most esthetic, while an NCA of 170 degrees was perceived as the least esthetic by all groups. Generally, an NCA greater than 145 degrees was perceived as less esthetic than an NCA smaller than 145 degrees. There was no significant difference between the scores of the observer groups for the silhouettes except for the female silhouettes with an NCA of 125 degrees or 150 degrees and the male silhouettes with an NCA of 145 degrees or 150 degrees. For both the female and male silhouettes, the further the NCA increased or decreased from 145 degrees, the less esthetic it was perceived to be. A significant increase in NCA was perceived as less esthetic than a significant decrease. The range of NCAs perceived as esthetic varied between 120 degrees and 145 degrees for women and between 130 degrees and 150 degrees for men. These ranges of variability of NCA may provide clinicians with useful information for orthognathic surgical planning.

The Effect of Orthognathic Surgery on the Hourglass Appearance of the Neck.

In frontal view, the transition from the upper aspect of the neck to the inferior border of the mandible has a subtle hourglass appearance. The aim of this study was to evaluate the effect of the orthognathic surgery on the hourglass appearance of the neck in patients with Class II dentofacial deformity. Twenty-six patients with Class II dentofacial deformity who underwent bilateral sagittal split osteotomy alone or in combination with Le Fort I osteotomy and/or genioplasty were included in this study. The width of the most upper part, the width of the narrowest part, the length of the upper part, the height of the upper part, the depth, and the angle of the hourglass were measured on frontal facial photographs obtained preoperatively and at sixth months postoperatively. The decrease in the width of the narrowest part ( P =0.012) and the right ( P <0.001) and left ( P <0.001) angles of the hourglass were statistically significant. Also, increase in the right ( P =0.036) and the left ( P =0.004) depths of the hourglass were statistically significant. Orthognathic surgery procedures performed to correct Class II dentofacial deformity positively affects the hourglass appearance of the neck, therefore neck esthetics should also be considered in the preoperative evaluation of facial esthetics.

Effects of Hyaluronic Acid and Hydroxyapatite/Beta-tricalcium Phosphate in Combination on Bone Regeneration of a Critical-size Defect in an Experimental Model.

Hyaluronic acid (HyA) is an outstanding new product in the field of oral and maxillofacial surgery. The aim of this study was to evaluate the effects of HyA on bone regeneration in critical-size calvarial defects. Twenty-four female Sprague-Dawley rats were used in the present study. In each rat, 4 critical-size defects received different treatments: no treatment (control); HyA; Graft; and HyA + Graft combination. New bone formation, defect closure, inflammation, vascular proliferation, immature bone formation, mature bone formation, and bone marrow existence were investigated based on histological findings. The healing parameters related to bone formation (new bone formation, defect closure, immature bone formation) were significantly higher in the HyA group compared with the control group. However, HyA alone was unable to induce sufficient bone regeneration compared with treatments involving graft materials (Graft and HyA + Graft). In the Graft and HyA + Graft groups, prominent enhancement of all healing parameters was noted. The present results demonstrate that HyA alone did not adequately enhance bone regeneration in critical-size defects. Moreover, addition of HyA to a biphasic alloplastic graft material did not result in improved regeneration compared with the graft material alone.

Positive effect of platelet rich fibrin on osseointegration

BACKGROUND: Leukocyte-platelet rich fibrin (L-PRF) is a second generation platelet concentrate clinically used to accelerate tissue healing and bone regeneration. Achieving reduced implant osseointegration time could provide immediate or early loading of implants. The aim of this study was to evaluate the L-PRF-induced osseointegration and bone-implant contact (BIC) in an experimental animal model. MATERIAL AND METHODS: Twelve 4-month-old New Zealand white rabbits were used. Following general anesthesia, 3-5 mL of blood was obtained from the central artery in rabbit ear and L-PRF was prepared. Two implant cavities (5 mm long and 3 mm in diameter) were created in each tibia with a total of four cavities in each animal. Two of these cavities were selected and covered with PRF (test group). The remaining L-PRF was used to soak the implants placed into the L-PRF covered sockets. Other cavities were left as controls. In total, 48 implants were placed. Animals were sacrificed after two, three, or four weeks. Histological samples were obtained and periimplant tissues were histomorphometrically evaluated for bone-to-implant contact and new bone formation. RESULTS: Histomorphometric analyses of the defects revealed that the L-PRF was detectable up to the second week. Application of L-PRF increased the rate and amount of new bone formation in the experimental group compared to the control group. Bone-to-implant contact was enhanced when the surface was prewetted with LPRF (p < 0.01). CONCLUSIONS: The results of this study demonstrated that L-PRF application may increases amount and rate of new bone formation during the early healing period and provides a faster osseointegration around implants