Comparison of onset anesthesia time and injection discomfort of 4% articaine and 2% mepivacaine during teeth extractions.

OBJECTIVE: To investigate the speed of action and injection discomfort of 4% articaine and 2% mepivacaine for upper teeth extractions. MATERIALS AND METHODS: Forty-five patients were included in the articaine 4% group, and 45 in the mepivacaine 2% control group. After all injections, soft and hard tissue numbness was objectively gauged by dental probe at intervals of 15 s. Furthermore, the discomfort of the injections were recorded by the patients after each treatment on standard 100 mm visual analog scales, tagged at the endpoints with "no pain" (0 mm) and "unbearable pain" (100 mm). RESULTS: There were significant differences in the meantime of first numbness to associated palatal mucosa and tooth of patients between mepivacaine and articaine buccal infiltration (BI) groups P = 0.01 and 0.01. Patients in the articaine group recorded earlier palatal mucosa and teeth numbness than those in the mepivacaine group. With regards to the discomfort of the needle injections, palatal injection was significantly more painful than BI (t-test: P < 0.001). Articaine buccal injection was significantly more painful than mepivacaine buccal injection (t-test: P <0.001). However, articaine palatal injection was less painful than articaine BI. Clinically, anesthesia onset time was faster in anterior upper teeth than upper middle and posterior teeth. CONCLUSIONS: BIs with 4% articaine was faster in achieving palate and teeth anesthesia than 2% mepivacaine for extraction of upper maxillary teeth. Patients in mepivacaine BI and articaine palatal injection groups reported less pain with needle injection. Failure of anesthesia was noticeable with maxillary multiple-rooted teeth.

Resolution of neurosensory deficit after mandibular orthognathic surgery: A prospective longitudinal study.

OBJECTIVES: To investigate the longitudinal resolution of neurosensory deficit (NSD) and the possible risk factors that might contribute to NSD following mandibular orthognathic procedures. STUDY DESIGN: A prospective longitudinal observational study on patients who had mandibular orthognathic procedures was performed. Standardized neurosensory assessments were performed. The 2 years longitudinal resolution and risk factors of NSD including patients' age and gender, specific mandibular procedures and surgeons' experience were analyzed. RESULTS: 66 patients (44 females) with 132 sides of mandibular procedures were enrolled in the study. Surgical procedures included mandibular ramus surgery, anterior mandibular surgery, or the combination of the two. The overall occurrences of subjective NSD improved from 78.8% at postoperative 2 weeks to 13.8% at post-operative 2 years. Combinations of ramus surgery and anterior mandibular surgery increased the risk of NSD at the first three post-operative months (p < 0.05). Patients' age and gender, and surgeons' experience were not found to be risk factors of NSD after mandibular orthognathic surgery. CONCLUSION: The occurrence of NSD after mandibular orthognathic procedures reduced progressively within the post-operative 2 years. Combination of mandibular ramus surgery and anterior mandibular surgery increased the risk of NSD in the early post-operative period.

Risk factors of neurosensory disturbance following orthognathic surgery.

OBJECTIVES: To report the incidence of objective and subjective neurosensory disturbance (NSD) after orthognathic surgery in a major orthognathic centre in Hong Kong, and to investigate the risk factors that contributed to the incidence of NSD after orthognathic surgery. MATERIALS AND METHODS: A retrospective cross-sectional study on NSD after orthognathic surgery in a local major orthognathic centre. Patients who had bimaxillary orthognathic surgery reviewed at post-operative 6 months, 12 months or 24 months were recruited to undergo neurosensory tests with subjective and 3 objective assessments. Possible risk factors of NSD including subjects' age and gender, surgical procedures and surgeons' experience were analyzed. RESULTS: 238 patients with 476 sides were recruited. The incidences of subjective NSD after maxillary procedures were 16.2%, 13% and 9.8% at post-operative 6 months, 12 months and 24 months, respectively; the incidences of subjective NSD after mandibular procedures were 35.4%, 36.6% and 34.6% at post-operative 6 months, 12 months and 24 months, respectively. Increased age was found to be a significant risk factor of NSD after orthognathic surgery at short term (at 6 months and 12 months) but not at 24 months. SSO has a significantly higher risk of NSD when compared to VSSO. SSO in combination with anterior mandibular surgery has a higher risk of NSD when compared to VSSO in combination with anterior mandibular surgery or anterior mandibular surgery alone. Gender of patients and surgeons' experience were not found to be risk factors of NSD after orthognathic surgery. CONCLUSION: The incidence of NSD after maxillary and mandibular orthognathic procedures at post-operative 6 months, 12 months and 24 months was reported. Increased age was identified as a risk factor of short term post-operative NSD but not in long term (24 months or more). Specific mandibular procedures were related to higher incidence of NSD after orthognathic surgery.