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Functional Sensory Return Following Trigeminal (V3) Nerve Repair
Oral Abstract Session 5 3. Four were crushed with mosquito forceps. 4. Four were stretched to greater than 120 percent of their original length with mosquito forceps. Method of Data Analysis: In each case the damaged area was photographed, resected with 5 mm margins, embedded in paraffin wax, sectioned in 5 micron sections and stained with hematoxylin and eosin and examined histologically. Results: The scalpel clinically produced a clean wound with sharply defined edges, and this was confirmed histologically with minimal disturbance to the fascicles. The 702 fissure bur produced a ragged stretched type injury clinically, and histologically this was confirmed with an irregular edged border to the lesion with stretching and internal damage to the fascicles adjacent to the wound. The crushed injuries clinically caused considerable apparent damage to the nerve, and this was confirmed histologically with crushing and disruption of the fascicles and reduction to approximately 25 per cent of their pre-injury thickness. The stretch injury clinically showed no change and looked normal, but histologically showed irregular internal disruption of the fascicles over the whole area that was subject to the stretching movement. Conclusion: The different modalities of nerve injury produce a different type of injury both clinically and histologically and this has implications both for natural recovery and the indications for surgical intervention. Clinical recovery may occur best with close approximation of a sharply incised scalpel type wound or excision of a crushed area of nerve and re-approximation of the nerve endings, but a ragged wound caused by a fissure bur may require excision back to healthy nerve with subsequent reapproximation, while in the stretching injury it may be difficult to ascertain the margins of the injury, since it may occupy quite a length of nerve and it may be most appropriate to rely on a natural healing process to get the best results in these cases. References Pogrel MA: The results of microsurgery of the inferior alveolar and lingual nerve. J Oral Maxillofac Surg 66:485, 2002 Zuniga JR, Meyer RA, Gregg JM, et al: The accuracy of neurosensory testing for nerve injury diagnosis. J Oral Maxillofac Surg 56:2, 1998
Functional Sensory Return Following Trigeminal (V3) Nerve Repair Srinivas Susarla, BA, Oral and Maxillofacial Surgery, 55 Fruit Street, Warren 1201, Boston, MA 02114 (Donoff RB; Kaban LB; Dodson TB) Statement of the Problem: The aims of this study were: 1) to estimate the proportion of patients who achieved functional sensory return (FSR) one year after inferior AAOMS • 2005
alveolar or lingual nerve repair and 2) to identify risk factors associated with failure to achieve FSR. Materials and Methods: Using a retrospective cohort study design, we developed a sample composed of subjects who underwent lingual or inferior alveolar nerve repair at the Massachusetts General Hospital during the period of January 1998-January 2004. Eligible subjects had at least one post-operative visit. For subjects having bilateral nerve repair, one side was randomly selected for analysis. Predictor variables were categorized as demographic, anatomic, and operative. The outcome variable was the time to FSR, measured in months. Method of Data Analysis: Kaplan-Meier survival methods were used to estimate the proportion of subjects with FSR at one year. Univariate Cox proportional hazard models were used to measure associations between the predictor and outcome variables. Multivariate Cox proportional hazards modeling was used to identify risk factors for the failure to reach FSR at one year. Results: During the study interval, 85 subjects underwent nerve repair. The eligible study sample was composed of 60 patients having 60 nerves repaired. There were no statistically significant differences in the distribution of the predictor variables between eligible and ineligible study subjects. The mean age of subjects was 28.6 ⫾ 8.3 years; 68.3 percent were female. The majority (86.7 percent) of patients presented with a pre-operative chief complaint of altered sensation and had lingual nerve damage (93.3 percent) that was repaired by direct suturing (75.0 percent). The mean interval between injury and repair was 4.8 ⫹ 6.6 months. At one-year post-operatively, 82.7% of the subjects had achieved FSR (95% CI: 72% – 93%). The mean time to FSR was 8.1 ⫾ 0.8 months; the median time was 6.8 ⫾ 1.8 months. None of the predictor variables were associated with the time to FSR in univariate or multivariate analyses. Conclusion: The majority of patients undergoing trigeminal (V3) nerve repair achieve functional sensory return within one year of surgical repair. There were no identifiable risk factors associated with failure to achieve FSR at one year. References Dodson TB, Kaban LB: Recommendations for management of trigeminal nerve defects based on a critical appraisal of the literature. J Oral Maxillofac Surg 55:1380, 1997 Pogrel MA: The results of microneurosurgery of the inferior alveolar and lingual nerve. J Oral Maxillofac Surg 60:485, 2002 Funding Source: Oral and Maxillofacial Surgery Foundation Fellowship in Clinical Investigation (S.M.S.), Massachusetts General Hospital Department of Oral and Maxillofacial Surgery Education and Research Fund (S.M.S., T.B.D.)
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Functional Sensory Return Following Trigeminal (V3) Nerve Repair Srinivas Susarla, BA, Oral and Maxillofacial Surgery, 55 Fruit Street, Warren 1201, Boston, MA 02114 (Donoff RB; Kaban LB; Dodson TB) Statement of the Problem: The aims of this study were: 1) to estimate the proportion of patients who achieved functional sensory return (FSR) one year after inferior AAOMS • 2005
alveolar or lingual nerve repair and 2) to identify risk factors associated with failure to achieve FSR. Materials and Methods: Using a retrospective cohort study design, we developed a sample composed of subjects who underwent lingual or inferior alveolar nerve repair at the Massachusetts General Hospital during the period of January 1998-January 2004. Eligible subjects had at least one post-operative visit. For subjects having bilateral nerve repair, one side was randomly selected for analysis. Predictor variables were categorized as demographic, anatomic, and operative. The outcome variable was the time to FSR, measured in months. Method of Data Analysis: Kaplan-Meier survival methods were used to estimate the proportion of subjects with FSR at one year. Univariate Cox proportional hazard models were used to measure associations between the predictor and outcome variables. Multivariate Cox proportional hazards modeling was used to identify risk factors for the failure to reach FSR at one year. Results: During the study interval, 85 subjects underwent nerve repair. The eligible study sample was composed of 60 patients having 60 nerves repaired. There were no statistically significant differences in the distribution of the predictor variables between eligible and ineligible study subjects. The mean age of subjects was 28.6 ⫾ 8.3 years; 68.3 percent were female. The majority (86.7 percent) of patients presented with a pre-operative chief complaint of altered sensation and had lingual nerve damage (93.3 percent) that was repaired by direct suturing (75.0 percent). The mean interval between injury and repair was 4.8 ⫹ 6.6 months. At one-year post-operatively, 82.7% of the subjects had achieved FSR (95% CI: 72% – 93%). The mean time to FSR was 8.1 ⫾ 0.8 months; the median time was 6.8 ⫾ 1.8 months. None of the predictor variables were associated with the time to FSR in univariate or multivariate analyses. Conclusion: The majority of patients undergoing trigeminal (V3) nerve repair achieve functional sensory return within one year of surgical repair. There were no identifiable risk factors associated with failure to achieve FSR at one year. References Dodson TB, Kaban LB: Recommendations for management of trigeminal nerve defects based on a critical appraisal of the literature. J Oral Maxillofac Surg 55:1380, 1997 Pogrel MA: The results of microneurosurgery of the inferior alveolar and lingual nerve. J Oral Maxillofac Surg 60:485, 2002 Funding Source: Oral and Maxillofacial Surgery Foundation Fellowship in Clinical Investigation (S.M.S.), Massachusetts General Hospital Department of Oral and Maxillofacial Surgery Education and Research Fund (S.M.S., T.B.D.)
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