most odontogenic infections arise in otherwise healthy patients as a sequel to pulp necroses caused by caries or trauma , periodontal infections , and or pericoronitis . the majority of odontogenic infections are self - limiting and may drain spontaneously . however , these infections may drain into the facial spaces adjacent to the oral cavity and spread aggressively leading to more severe infection . hence , timely efforts are required to establish a patent airway in addition to debridement , incision , and drainage and appropriate antimicrobial therapy . determining whether a facial space infection is an abscess or cellulitis may be difficult clinically , but is very important as both may require different treatments . a swelling if localized and characterized by the sensation on palpation that there is fluid movement under the tissue indicates pus is present . a swelling that spreads through adjacent soft tissue and dissects tissue spaces along fascial planes is considered to be a diffuse swelling or cellulitis . some authors have stated that an abscess must be drained surgically and that cellulitis responds to systemic antibiotics . failure to diagnose correctly leads to inappropriate or delayed therapy which , in turn , can lead to medical complications , extra emergency department or clinic visits , and increased costs . clinically , there are general differences between a cellulitis and an abscess . a cellulitis is the initial presentation of an infection and is thought to be an acute process . an abscess , while also acute , is often considered the resolution phase of a clinical swelling . the pain described by patients with a cellulitis tends to be more severe and generalized than the localized pain associated with an abscess . a cellulitis often presents with swelling , warmth , erythema , and tenderness over the affected area and equates to the descriptive terms  tumor ,   calor ,   rubor  , and/or  dolor  . the firmer the cellulitis and the more rapidly it spreads tends to indicate a more severe infection . the borders of cellulitis are typically large , smooth , ill - defined , and do not contain pus . an abscess usually has small and well - circumscribed borders and is soft or fluctuant to palpation indicating a pus - filled cavity . it has been suggested in both the medical and dental literature that the use of ultrasonography ( usg ) can aid in the diagnosis of swellings and also in locating the depth of an abscess to allow a more accurate location for an incision for drainage procedure . while magnetic resonance imaging ( mri ) and computed tomography ( ct ) are valuable diagnostic aids in imaging soft tissue lesions and the spread of infections into fascial spaces ; they are not readily available in many dental clinics , are expensive and time - consuming , and expose the patient to large doses of radiation . usg is quick , widely available , inexpensive , relatively painless , and can be repeated as often as necessary without risk to the patient . the usg method could be considered to be quick , noninvasive , sensitive , widely available , inexpensive , and relatively painless . usg has been used to depict swellings , cysts , lymph nodes , salivary glands , vascular structures , and inflammatory masses in the head and neck region . usg could be very useful if repeated follow - up examinations required as it has no radiation exposure to patients . the purpose of this prospective investigation was to compare the accuracy of clinical examination and clinical examination plus usg in the diagnosis of cellulitis and abscess in symptomatic patients with a diagnosis of facial space infection . the usg method could be considered to be quick , noninvasive , sensitive , widely available , inexpensive , and relatively painless . usg has been used to depict swellings , cysts , lymph nodes , salivary glands , vascular structures , and inflammatory masses in the head and neck region . usg could be very useful if repeated follow - up examinations required as it has no radiation exposure to patients . the purpose of this prospective investigation was to compare the accuracy of clinical examination and clinical examination plus usg in the diagnosis of cellulitis and abscess in symptomatic patients with a diagnosis of facial space infection . this study was conducted in the department of oral and maxillofacial surgery , government dental college srinagar . the study was time based , conducted over a period of 23 months from january 2011 to december 2012 . the study group comprised of 20 patients of both sexes with age ranging from 18 to 70 years . all the patients diagnosed to have superficial facial space infections by clinical and radiographic examinations were included in the study . all the patients clinically diagnosed as having odontogenic infections spreading to the facial spaces , patients of various ages with no sex bar and patients who were willing to participate in the study were included in the study . patients were excluded if they had allergies to local anesthetics , were pregnant , or had a history of significant medical conditions . potential benefits of undergoing thorough clinical , radiographic , and ultrasonographic investigations were made known to the potential participants . only those individuals who agreed to undergo these procedures recording of demographic data , history regarding facial swelling , general history , and physical examination were carried out in a systematic manner . the subjects provided written informed consent . to qualify for this study , patients had a symptomatic necrotic tooth and clinical swelling at the time of treatment . a clinical examination was performed by palpating the swelling to determine if it was considered a cellulitis or abscess . a diagnosis of cellulitis was made if the swelling was firm , warm , or hot , and no observable fluid movement ( purulence ) was detected . a fluctuant swelling was diagnosed if there was believed to be fluid movement under the tissue , indicating that pus was present . the swelling was then evaluated using a portable acuson p50 ( siemens , munich , germany ) ultrasound unit that produces high resolution images . the best probe to use for the assessment of superficial structures , such as an abscess or cellulitis , is a high frequency linear probe ( 8 - 12 mhz or higher ) . it has a maximum depth of 80 mm ( 8 cm ) and has a frequency range of 4.8 - 12.0 mhz . following a clinical examination , the ultrasonic transducer was placed over the swelling and a diagnosis of cellulitis or abscess was made . a water based aquasonic gel ( parker lab inc . , fairfield , nj ) was used as the medium between the transducer and the patient 's skin to eliminate air bubbles . the abscess showed a heterogenic , anechoic [ figure 2 ] , or hypoechoic mass containing variable amounts of internal echoes . the incision was made through the most dependent site of the swelling using a scalpel . a blunt dissection using a curved hemostat the success of the ultrasound versus clinical examination was based on whether purulence was detected and confirmed during incision and drainage . this study was conducted in the department of oral and maxillofacial surgery , government dental college srinagar . the study was time based , conducted over a period of 23 months from january 2011 to december 2012 . the study group comprised of 20 patients of both sexes with age ranging from 18 to 70 years . all the patients diagnosed to have superficial facial space infections by clinical and radiographic examinations were included in the study . all the patients clinically diagnosed as having odontogenic infections spreading to the facial spaces , patients of various ages with no sex bar and patients who were willing to participate in the study were included in the study . patients were excluded if they had allergies to local anesthetics , were pregnant , or had a history of significant medical conditions . all the patients clinically diagnosed as having odontogenic infections spreading to the facial spaces , patients of various ages with no sex bar and patients who were willing to participate in the study were included in the study . patients were excluded if they had allergies to local anesthetics , were pregnant , or had a history of significant medical conditions . potential benefits of undergoing thorough clinical , radiographic , and ultrasonographic investigations were made known to the potential participants . only those individuals who agreed to undergo these procedures recording of demographic data , history regarding facial swelling , general history , and physical examination were carried out in a systematic manner . a clinical examination was performed by palpating the swelling to determine if it was considered a cellulitis or abscess . a diagnosis of cellulitis was made if the swelling was firm , warm , or hot , and no observable fluid movement ( purulence ) was detected . a fluctuant swelling was diagnosed if there was believed to be fluid movement under the tissue , indicating that pus was present . the swelling was then evaluated using a portable acuson p50 ( siemens , munich , germany ) ultrasound unit that produces high resolution images . the best probe to use for the assessment of superficial structures , such as an abscess or cellulitis , is a high frequency linear probe ( 8 - 12 mhz or higher ) . it has a maximum depth of 80 mm ( 8 cm ) and has a frequency range of 4.8 - 12.0 mhz . following a clinical examination , the ultrasonic transducer was placed over the swelling and a diagnosis of cellulitis or abscess was made . , fairfield , nj ) was used as the medium between the transducer and the patient 's skin to eliminate air bubbles . the abscess showed a heterogenic , anechoic [ figure 2 ] , or hypoechoic mass containing variable amounts of internal echoes . the incision was made through the most dependent site of the swelling using a scalpel . a blunt dissection using a curved hemostat the success of the ultrasound versus clinical examination was based on whether purulence was detected and confirmed during incision and drainage . twenty adult patients participated in this study ; eight were female ( 40.0% ) and 12 were male ( 60.0% ) [ table 1 ] and [ figure 3 ] . 
 table 2 and figure 4 shows the age wise distribution of patients . maximum number of patients were in the age group of 31 - 40 years . swellings were seen in the maxilla in five patients ( 25.0% ) and the mandible in 15 patients ( 75.0% ) , 11 patients ( 55.0% ) had left - sided swelling , and nine patients ( 45.0% ) had right sided swelling . all subjects ( 100% ) overall , four teeth ( 20.0% ) associated with the swellings were maxillary anterior , one ( 5.0% ) was maxillary posterior , none ( 0.0% ) were mandibular anterior , and 15 ( 75.0% ) were mandibular posterior . preoperative variables for all subjects preoperative variables for all subjects table 4 and figure 6 shows the tooth type grouped by cellulitis and abscess . for the cellulitis group , three teeth ( 37.5% ) were maxillary anterior , zero ( 0% ) were maxillary posterior , one ( 0% ) were mandibular anterior , and five ( 62.5% ) were mandibular posterior . for the abscess group , zero tooth ( 0% ) was maxillary anterior , one ( % ) was maxillary posterior , zero ( 0% ) was anterior mandibular , and 10 ( 83.3% ) were mandibular posterior . the cellulitis group had two females ( 25% ) and six males ( 75% ) and the abscess group had five females ( 41.6% ) and seven males ( 58.3% ) . tooth type and gender grouped by cellulitis and abscess tooth type and gender grouped by cellulitis and abscess table 5 and figure 7 demonstrates the number of cellulitis versus abscess type swellings recorded with clinical exam alone , ultrasound , and findings after incision for drainage . diagnosis of abscess was made seven out of 20 times ( 35% ) and cellulitis was diagnosed 13 out of 20 times ( 65% ) with clinical examination . in ultrasound abscess was diagnosed 12 out of 20 times ( 60% ) and cellulitis was diagnosed in eight out of 20 times ( 40% ) . the number of swellings determined to be abscess or cellulitis , found after incision for drainage , were 11 ( 55.0% ) and nine ( 45.0% ) , respectively . diagnoses after : clinical exam , ultrasound exam , and incision for drainage diagnoses after clinical exam , ultrasound , and incision for drainage table 6 and figure 8 clinical exam alone versus usg for diagnosis is demonstrated . with clinical examination alone a correct diagnosis was made 17 of 20 times ( 85% ) and incorrect diagnosis was made in three of 20 times ( 15% ) . with usg a correct diagnosis was made 19 of 20 times ( 90% ) and incorrect diagnosis was made in one of 20 times ( 5% ) cases . clinical exam versus ultrasound correct and incorrect diagnoses clinical exam versus ultrasound correct and incorrect diagnoses table 7 and figure 9 shows the statistical analysis of diagnosis using fisher 's exact testandinfers that sensitivity of usg examination was found to be 87% as that compared to sensitivity of clinical examination which was 62% . the purpose of this study was to compare the accuracy of usg versus clinical examination alone in the diagnosis of cellulitis and abscess in symptomatic patients with facial space infection . it is believed that identifying the correct diagnosis of facial space swelling is important to render the appropriate treatment . however , it has been suggested that the two conditions ( abscess and cellulitis ) may coexist making diagnosis difficult which in turn may lead to missed abscesses and/or unnecessary invasive procedures . failure to diagnose correctly may lead to inappropriate or delayed therapy which in turn can lead to medical complications , extra emergency department , and increased costs . in the present study , the swellings were not  staged  because a clear cut diagnosis by clinical exam or ultrasound to determine cellulitis or abscess was being evaluated . it is not clear in the literature what is expected to be found in the other stages upon surgical intervention . for example , is pus expected to be found in the preabscess stage since it is considered to be between the cellulitis and abscess stages ? it is possible that most swellings are a combination of the two making diagnosis very difficult . making a clear cut diagnosis or knowing the stage of the swelling is important if the treatment of the swellings is different . twenty adult patients participated in this study ; eight were female ( 40.0% ) and 12 were male ( 60.0% ) . the distribution consisted of patients who presented to the department of oral and maxillofacial surgery , government dental college , srinagar with odontogenic swelling . liddel and locker found that women are significantly more affected by pain , have a lower acceptance of pain , a greater fear of pain , and avoid pain more than males . fillingim et al . also found that women had significantly lower thresholds for the detection and tolerance of pain . the present study used incision for drainage as the standard in determining cellulitis or abscess because it is the most common method used . if pus was expressed after the incision for drainage , the swelling was classified to be an abscess . if pus was not expressed then the swelling was classified a cellulitis . a higher incidence for abscess was found in the present study compared to peleg and coauthor 's findings and almost similar incidence than squire and coauthor 's findings . the incidence for cellulitis in this study was higher than that found by squire , et al . the results of this study found the sensitivity ( the ability to detect cellulitis when it was cellulitis ) of the clinical exam alone was 62.5% and for usg was 75% . overall , the findings of this study suggest that usg may be useful as an adjunct to clinical exam in differentiating between cellulitis and abscess . this agrees with many of the other studies done using ultrasound as an aid . a review article by ramirez - schrempp , et al ultrasound is an efficient , noninvasive diagnostic tool which can augment the physician 's clinical examination . ultrasound has been shown to be superior to clinical judgment alone in determining the presence or the absence of occult abscess formation , ensuring appropriate management , and limiting unnecessary invasive procedures  . this study investigated the use of usg as a valuable aid to clinical examination in differentiating between abscess and cellulitis . the purpose was to compare the accuracy of usg versus clinical examination in the diagnosis of cellulitis and abscess in symptomatic patients with a diagnosis of superficial facial space infection . studies in both the medical and dental literature suggest that ultrasound is a promising adjunct . however , as thoroughly discussed , many of these studies were underpowered or were not well - controlled research designs . in this study , the results of this study show that there was statistical difference between clinical examination alone and usg in making the correct diagnosis . the sensitivity , specificity , positive predictive , negative predictive , and accuracy were not similar for all methods tested . from the results of this study , ultrasound is recommended as an adjunct to clinical examination in differentiating between cellulitis and abscess .
introduction : superficial facial space infections represent a significant amount of the dental problems that present to hospital . determining whether an odontogenic swelling is a cellulitis or abscess is difficult , but important as both may require different treatments . 
 the use of an ultrasound may aid in differentiating cellulitis and abscess . 
 this study was done to compare the accuracy of clinical examination alone versus ultrasonography ( usg ) in the diagnosis of cellulitis and abscess in symptomatic patients with a diagnosis of superficial facial space infection.materials and methods : twenty patients ( 1870 years ) diagnosed as superficial facial space infections by clinical and radiographic examinations were included in the study and patients with significant medical conditions were excluded . 
 the provisional clinical diagnosis was made after a thorough history was taken and clinical examination was performed to determine if the swelling was a cellulitis or abscess . 
 swelling was then evaluated using the ultrasonic transducer which was placed over the swelling to aid the diagnosis which was again recorded . 
 an incision and drainage procedure was performed after the administration of local anesthesia . 
 the success of the ultrasound intervention versus clinical examination was based on whether frank exudation was detected during incision and drainage of such swellings.results:the statistical analysis found that usg is a valuable diagnostic aid for detection of abscess or cellulitis in head and neck facial space infections.interpretation and conclusion : the findings of this prospective analysis indicate that there was statistical difference between clinical examination alone and usg in making the correct diagnosis . the sensitivity , specificity , positive predictive , negative predictive , and accuracy were not similar for all methods tested . from the results of this study , 
 ultrasound is recommended as an adjunct to clinical examination in differentiating between cellulitis and abscess .