This was a survey based descriptive study. This study has been done among the dentists of northern region of Saudi Arabia. This was the first study of its kind, done in this region of Saudi Arabia. A questionnaire was designed, regarding pattern of prescription of antibiotics by the dentists in northern region of Saudi Arabia and use of antibiotics in the treatment of different endodontic conditions during endodontic treatment. This questionnaire was distributed among 200 dentists in the north of Saudi Arabia. This study will encourage the dentists of the northern region of Saudi Arabia to be up to date about the current and prospective guidelines for the prescription of antibiotics and follow these guidelines for the antibiotic prescription.

In the present study out of total 200 dentists 157 has responded and the response rate was 78.5%. The demographic characteristics of the responding dentists are described in [Table/Fig-1]. In [Table/Fig-2] the percentage of the responding dentists is listed who were prescribing the antibiotics for various pulpal and periapical conditions. The antibiotic choice of the responding dentists was indicated in [Table/Fig-3].

In this questionnaire based cross-sectional study, the antibiotic prescription pattern of the dentists has been evaluated. The questions and endodontic conditions which have been proposed in our questionnaire were based on those which have been proposed in previous surveys and done in USA [13], Spain [14] and India [15]. This study has shown 78.5% response rate. The 78.5% response rate is considered as an acceptable rate for a survey based study. To prescribe the antibiotics for an endodontic infection, the endodontic infection must be persistent or it should have a systemic involvement i.e. high grade fever, swelling, lymphadenopathy, trismus or malaise [13] otherwise antibiotic prescriptions is not justified.

In the present study [Table/Fig-2] shows the percentages of respondents who prescribe the antibiotics for various endodontic conditions. In our study the first condition of necrotic pulp with acute apical periodontitis, swelling and mod/ severe preoperative symptoms got 77% antibiotic prescription by the responding dentists. If this is agreed that this condition has the systemic involvement then antibiotic prescription is justified along with nonsurgical debridement of the root canal system and incision and drainage. 77% response rate in the present study is comparable with response rates of 90.2% and 94.5% of Indian and Spanish dentists respectively for this condition [14,15].

In the present study the second condition of necrotic pulp with acute apical Periodontitis, no swelling and mod/severe preoperative symptoms got 59% antibiotic prescriptions by the responding dentists. This 59% response rate is considerably high and it is similar to the previous studies, having the response range from 30%-71% [13,15,16]. The 59% response rate in our study shows an over-use of antibiotics for this condition. Ideally there is no need of antibiotic prescription in this condition and proper treatment for this condition is non- surgical root canal treatment and analgesics. The third endodontic condition in our study was necrotic pulp with chronic apical periodontitis, sinus tract and no or mild preoperative symptoms. Although the effective management of this condition without systemic involvement is, non surgical endodontic treatment, to remove the cause along with drainage and analgesics for pain if indicated, but 46.4% of the respondents prescribed the antibiotics even in this condition, which seemed to be unjustified. But if the patient is having acute flare up along with systemic involvement, and sinus tract is not healed then antibiotic prescription is justified.

The fourth endodontic condition in the present study was irreversible pulpitis with acute apical periodontitis, moderate or severe preoperative symptoms. As this is a non infected condition with the vital pulp and without systemic involvement, thus this condition does not necessitate the prescription of antibiotics, only the removal of cause and prescription of the analgesics, when indicated will suffice for this Condition. But in the present study 42% of the respondents have prescribed the antibiotics for this condition which is totally unjustified for this condition and the scientific guidelines for antibiotics prescription are totally neglected. The same unjustified and unnecessary antibiotic prescription for this condition is found in the previous studies in a range of 30% -71 % [13,15,16].

The fifth endodontic condition of this survey was necrotic pulp, with chronic apical periodontitis, no swelling and no or mild preoperative symptoms. Although there is no clear cut indication for the prescription of antibiotic but even then 23.5% of the respondents have prescribed the antibiotics for this condition where as in similar survey based studies the Spanish dentists and Indian dentists prescribed antibiotics for this condition only 14.3% and 38.2% respectively [14,15]. Similarly a higher percentage of the responding dentists in surveys done in USA, prescribed the antibiotics for similar condition [14,16]. Again, this is an unjustified and unnecessary antibiotic prescription because the justified treatment for this condition is the removal of the cause by nonsurgical endodontic treatment.

The sixth endodontic condition of this survey was irreversible pulpitis with moderate/severe preoperative symptoms. In this condition the pulp is vital and there are no signs and symptoms of systemic involvement so there is no indication for the prescription of antibiotics in this condition [17]. In the present study 27.3% of the Responding dentists prescribed antibiotics for this condition which is totally unjustified and unnecessary. This finding in the present study showed that the scientific basis for the prescription of antibiotics in the present condition is neglected by a large percentage of the responding dentists. In the previous surveys done in Spain, India and US 31% and 37.6% of the responding dentists respectively prescribed the antibiotics for this condition, which are comparable with our study [14,15].

In the present study, [Table/Fig-3] shows the percentages of various types of antibiotics which have been prescribed by responding dentists. Amoxicillin and clavulanic acid in combination is considered as a combination of choice for odontogenic infection because this combination has the broad antimicrobial spectrum and low incidence of bacterial resistance [18]. In the present survey the drug which was most prescribed by the responding dentists was amoxicillin and clavulanic acid combination 45.2 % followed by amoxicillin alone 33.7% and amoxicillin and metronidazole combination 15%. In a survey done by Spanish dentists amoxicillin in combination with calvulanic acid was prescribed by 61% of the respondents followed by amoxicillin. In 2007 the antibiotic treatment which has been prescribed by the Spanish dentists was amoxicillin and clavulanic acid, followed by amoxicillin alone [19]. Amoxicillin was a principal antimicrobial agent in the European countries [20]. Amoxicillin being broad spectrum is a drug of choice to treat the odontogenic infection, but it may cause antibiotic resistance [21]. In Contrast in the USA amoxicillin was prescribed only by 27.5% of members of AAE [14,16]. In the present survey, metronidazole was prescribed by the respondents as Falgyal and only a small percentage of the responding dentists prescribed it (5.7%). Metronidazole is very effective antimicrobial agent against obligate anaerobes but not as effective against facultative anaerobes. Therefore, when amoxicillin alone is not effective after 2-3 days of use then metronidazole should be recommended as a supplemental medication to increase the efficacy of amoxicillin [21]. Metronidazole is an effective antimicrobial agent against anaerobes but it has no activity against the aerobes and therefore metronidazole is required to be used in combination with other antimicrobial agent to be effective against odontogenic infections [22]. In the present survey the metronidazole was prescribed in combination with amoxicillin by 15% of the responding dentists and it was the third most commonly prescribed combination in our study. In a survey done by Spanish dentists, metronidazole was prescribed in combination with spiramycin by 23% of the endodontists [14,19]. The antibiotics should be used judiciously for well defined indications in the endodontics. The antibiotics use should only be considered as an adjunct to the non surgical endodontic therapy or in those cases where emergency treatment is not possible due to the busy schedule of the dentists [8,23]. At the end the dentists should have a sound knowledge about the endodontic indications for the prescription of antibiotic to restrict and prevent the misuse and overuse of antibiotics thus helping in the control of this global problem [24].

It is concluded from the present study that the dentists should know the scientific basis for the prescription of antibiotics during endodontic therapy. They should follow and should not neglect the current guidelines for antibiotic prescriptions. There should be community awareness programmes for the dentists about the global problems of misuse of antibiotics and antibiotic resistance so that they can play a role in controlling these global problems.