The majority of the 146 participants were Caucasian and female (). All 146 patients underwent surgery in the vicinity of sensory nerves associated with the mandibular division, but only 61 (42%) underwent surgery in the vicinity of the sensory nerves associated with the maxillary division. Patients who had a BSSO with a genioplasty were slightly younger (mean, 21.2 years) and those who had BSSO + LFI and a genioplasty were slightly older (mean, 27.4 years) than patients who did not have a genioplasty ().
PATIENTS’ SELECTION OF WORDS ACROSS CATEGORIES OF INTRUSIVENESS
At 1 week after surgery the median number of words chosen to describe the sensation(s) that occurred spontaneously or were evoked during assessment across all 4 sites on the face was 9 and 7, respectively. Twenty-five percent of the patients chose 14 or more words to describe the spontaneous alteration and 11 or more for the evoked alterations. By 6 months after surgery, the median number of words chosen by a patient for all sites decreased to 2 and 3 words, respectively. The seventy-fifth percentile value was 4 words for the spontaneous and 6 for the evoked assessments of sensation. This general trend was observed for each site individually. For example, for the chin at 1 week, patients selected an average of 3 words during both assessments but by 6 months, the average had decreased to 1 for the spontaneous and 2 for the evoked assessments of sensation.
PATIENTS’ SELECTION OF WORDS WITHIN CATEGORIES OF INTRUSIVENESS
Data from the chin are used to illustrate the percentages of patients who selected each word to describe the altered sensation at each of the 4 appointment times (). At 1 week after surgery some words were chosen by almost all patients. For example, 97% of the patients reported the sensation of “numb” (hypoesthesia category) during the spontaneous or evoked assessment of sensation on the chin. In contrast, the sensation of “wet” (also in the hypoesthesia category) was selected by only 2% of the patients. Similar differences for the report of numb versus wet were observed for all 4 sites, although the percentages were lower for the midface sites because fewer patients (42%) had maxillary surgery. “Rubbery” and “swollen” were commonly chosen from the hypoesthesia category for all 4 sites. The word “swollen” was selected more frequently than “rubbery” at 1 week after surgery, but “rubbery” was selected more frequently at 1, 3, and 6 months after surgery.
Similar to the hypoesthesia category, paresthesia was characterized largely by 3 words: “tingling,” “tickling,” and “itching.” The word “twitching” was selected almost as often as “itching.” Over 50% of the patients reported “tingling” during either the spontaneous or the evoked assessment of sensation on the chin at every appointment time (). A similar finding was made for the lower vermilion, but not for the upper vermilion or upper lip.
The 3 most commonly chosen words in the dysesthesia category were “tender,” “pricking,” and “burning.” Compared with the hypoesthesia and paresthesia categories, the 3 most commonly chosen words were less useful in characterizing dysesthesia. That is, many of the other words were selected almost as frequently. For example, the word “sore” was selected during either the spontaneous or evoked assessment of sensation on the chin by 15% of the patients at week 1 after surgery, approximating the 17% of patients who selected “tender,” the most commonly chosen word (). However, “sore” was chosen by only 7%, 2%, and 1% of the patients at 1, 3, and 6 months, respectively. It is plausible that “sore” better characterized the altered sensation from acute soft tissue trauma; whereas, “tender” better characterized inflammatory or neuropathic sequelae of the surgery.
Interestingly, only 9% of the patients reported “pain” on the chin at 1 week after surgery. At other appointment times and for other sites, the percentages of patients who reported pain were lower than 9%. This indicates that most patients did not consider their altered facial sensation as “painful,” even though it had an unnatural, and in some cases an unpleasant, character.
EXTENT OF RECOVERY AFTER SURGERY
Most patients had not recovered normal sensation at 1 or more sites on the face by 6 months after surgery. To illustrate, 98% of the subjects before surgery reported normal sensation, ie, they did not indicate spontaneous or evoked altered sensation at any site evaluated on the face. However, at 1 week after surgery less than 2% of the patients reported normal sensation (). Even after 6 months, only 37% and 16% of patients reported normal sensation at all 4 sites evaluated during the spontaneous and evoked assessments, respectively.
Percentage of patients who reported no altered sensation anywhere on the face at each of the postsurgery appointments.
RESOLUTION OF EVOKED VERSUS SPONTANEOUS ALTERATIONS IN SENSATION
At each of the 4 sites, more patients reported a qualitative alteration in sensation at 6 months after surgery by the evoked assessment than by the spontaneous assessment of sensation. For example, for the chin, 81% of patients selected at least 1 word to describe sensory alteration during the evoked assessment; whereas, only 58% selected at least 1 word during the spontaneous assessment (). Moreover, 66% of the patients were classified in the paresthesia and dysesthesia categories by the evoked assessment of sensation; whereas, only 47% were classified as such by the spontaneous assessment.
PERCENTAGE OF PATIENTS CLASSIFIED ACCORDING TO THE MOST INTRUSIVE CATEGORY OF WORD(S) CHOSEN TO DESCRIBE SENSATION ON THE LOWER VERMILION AND CHIN
COURSE OF RECOVERY AFTER SURGERY
Across all sites, there was a statistically significant inverse correlation between time after surgery and the maximum intrusiveness of the words chosen (IASmax) during both the spontaneous (IASmax spont, P < .001) and evoked (IASmax evok, P < .001) assessments of sensation. The percentages of patients who reported no alteration at any site on the face increased over time () while the percentages of patients who selected 1 or more words from the dysesthesia category decreased, at least for the assessment of spontaneous sensations (, bottom). These trends were observed for each individual site. In contrast, the percentage of patients in the hypoesthesia and paresthesia category remained about the same (, top and middle). Although the tendency was for the intrusiveness of the words selected to decrease over time, approximately 32% of the patients did not change categories, or the intrusiveness of the word(s) they chose worsened.
Figure 2 Percentage of patients classified into one of the altered sensation categories (hypoesthesia, paresthesia, dysesthesia) at each of the postsurgery appointments according to the most intrusive word(s) chosen to describe the altered sensation anywhere on (more ...)
RECOVERY OF PATIENTS WHO UNDERWENT DIFFERENT TYPES OF SURGERY, WITH AND WITHOUT GENIOPLASTY
The percentage of patients classified in each intrusiveness category for the upper lip () and the chin () at 1 week and 6 months is illustrated in the figures for the 4 surgical groups of patients characterized in : BSSO only with and without genioplasty, BSSO + LFI surgery with and without genioplasty. It is apparent from that, as expected, patients who had a maxillary procedure were more likely to experience altered sensation in the distribution of the maxillary nerve than those who had a mandibular procedure only. Moreover, consistent with the percentages shown in , the average intrusiveness (average IASspon and IASevok) for the upper lip and vermilion differed among the 4 surgical groups at both 1 week and 6 months. The average level of intrusiveness was significantly greater than 0, implying altered sensation, only for patients who underwent maxillary surgery. For these patients the mean values were similar for the upper lip and upper vermilion, and did not differ for patients with or without a genioplasty. As suggested by , most patients recovered normal sensation on the upper lip by 6 months after surgery (approximately 93% and on the upper vermilion, 95%). The percentages are high, in part, because 58% of the patients did not have maxillary surgery.
Figure 3 Using only words chosen to describe the upper lip during evoked testing, percentage of patients classified into one of the altered sensation categories (hypoesthesia, paresthesia, dysesthesia) at 1 week and 6 months separately for the 4 surgical groups: (more ...)
Figure 4 Using only words chosen to describe the chin during evoked testing, percentage of patients classified into one of the altered sensation categories (hypoesthesia, paresthesia, dysesthesia) at 1 week and 6 months separately for the 4 surgical groups: BSSO (more ...)
In contrast to recovery on the upper lip and vermilion, recovery was particularly poor on the chin with 81% of the patients selecting words in 1 or more categories to describe evoked sensations at 6 months after surgery (). At this time during recovery, the percentages of patients classified in the different categories of altered sensation were fairly similar for patients in the different surgical groups, all of whom had received BSSO ().
EFFECT OF TYPE OF SURGERY ON PATIENTS’ SELECTION OF WORDS
Differences among the surgical groups became evident upon analysis of the most common words that were chosen by patients at 1 or more of the postsurgical appointments. On the chin and lower vermilion, word usage was remarkably similar for patients who had BSSO only (without a genioplasty) or BSSO + LFI (without a genioplasty). For example, on the chin 100% of the patients who had BSSO only reported “numb” during either the spontaneous or evoked assessment of sensation, compared with 98% of the patients who had BSSO + LFI surgery. Remarkably similar agreement was found also for “tingling” (87% vs 85%) and “tender” (25% vs 23%). Similar findings were observed for the lower vermilion. These findings indicate that the addition of maxillary surgery to BSSO did not significantly affect the way patients perceived and reported altered sensation on their lower vermilion and chin.
In contrast, and as expected, those patients who did and did not have a maxillary procedure differed greatly in their word usage for the upper vermilion and upper lip. Unexpectedly, however, 11% of the patients who had surgery on the mandible only reported that the upper lip was “numb” at 1 or more appointments. In addition, 8% of the patients reported tingling and 8% reported tickling sensations.
Maxillary surgery in general was less likely to result in altered sensation than mandibular surgery. For example, “numb” and “tingling” were reported on the upper lip during the spontaneous or evoked assessment of sensation by 78% and 58% of the BSSO + LFI patients, respectively. In comparison, “numb” and “tingling” were reported on the chin by 98% and 85% of the same patients. In contrast to use of words from the hypoesthesia and paresthesia categories, words from the dysesthesia category were used with about the same frequency on mid-face and lower face sites. For example, “tender,” “prickling,” and “burning” were reported on the upper vermilion during the spontaneous or evoked assessment of sensation by 20%, 15%, and 5% of the patients, respectively. Similarly, the 3 words were reported on the lower vermilion by 20%, 15%, and 10% of the patients. These findings suggested that hypoesthesia and paresthesia, but not dysesthesia, were less of a problem on the midface than on the lower face after BSSO + LFI surgery.
There was a tendency for patients who had a genioplasty to more frequently choose descriptors for the lower face that are reflective of soft tissue trauma (“swollen” and “tender”) and inflammation (“tender” and “burning”) than were patients who did not have a genioplasty. For example, at some time after surgery “swollen” was reported on the chin by 60% of the patients who had genioplasty, compared with 41% of the patients who did not have genioplasty. Burning was reported on the chin and lower vermilion by 22% of the patients who had genioplasty, compared with 13% of those who did not.