This prospective study involved 100 patients indicated for extraction of the ipsilateral anterior and posterior maxillary teeth (N=100) who had presented to the Oral and Maxillofacial Surgery unit at AB Shetty Memorial Institute of Dental Sciences Mangalore, Karnataka, India between June 2017 to June 2019 after obtaining proper approval from Institutional Ethics Committee (Approval number: ABSM/EC10/2016). A pilot study was done which found that greater palatine nerve block lead to anterior region anaesthesia in 50 percent of the subjects. Based on this, sample size estimation was done. Out of the initial 100 patients recruited for the study, six of them were excluded as they underwent an additional minor surgical procedure (Alveoplasty). Therefore, a further six patients were included in the study. The minimal number of teeth planned for extraction was one from posterior region (molars or premolars) supplied by greater palatine nerve and one from anterior region (canine and incisors) supplied by nasopalatine nerve. If the patient gave consent for multiple extractions in requirement of complete denture then multiple teeth from the anterior as well as posterior region ipsilaterally were planned. The sequence of extraction proceeded from posterior most teeth first followed by anterior teeth.

Inclusion criteria: Patients above 18 years of age requiring extraction of anterior and posterior maxillary teeth of the same quadrant were included in the study.

Exclusion criteria: Patients requiring extraction of maxillary anterior teeth only or mandibular teeth or other minor surgical procedures and patients with neurological diseases, psychiatric problems, history of drug allergy, moderate to severe uncontrolled systemic conditions which required close observation and follow-up were excluded from the study.

All extractions were done by a single well-qualified oral surgeon, having good knowledge and skill in nerve block techniques and exodontia. Informed consent was taken from the patients before subjecting them to LA.

After positioning and draping the patient, the greater palatine foramen was palpated and the area was cleaned and dried with sterile gauze. A 2% Lignocaine gel (LOX-2% Gelly) was applied with a cotton swab at that region. After two minutes of topical anaesthetic (Lidocaine topical Aerosol USP 15%, ICPA) application, 0.4 ml of 2% lignocaine with 1:80,000 Epinephrine (LIGNOX 2% A, Indoco remedies Ltd.,) was injected using a 25-gauge short needle (DISPO VAN 2ml) from the opposite side of mouth to block the Greater Palatine nerve.

After an interval of five minutes, the anaesthetic effect on the palatal region from the last molar to the anterior most teeth was examined for each tooth with a Molts No: 9 periosteal elevator. The patients were examined for positive objective symptoms. Pain on the palatal mucosa was assessed using Numerical rating scale [8] of 0-10, (NRS; scale 0-10; 0=no pain, 5=moderate pain, 10=worst possible pain) as a tool for measuring its severity. NRS above 3 in any of the patients was administered with nasopalatine nerve block for the removal of the proposed anterior teeth.

Depending upon the effectiveness of anaesthesia on the palatal region reflection of the soft tissue could be carried out. A score of 0-3 was considered to be effective block; the score above 3 could elicit moderate pain during reflection referring to the failure of adequate anaesthesia. In such case where the effectiveness was questionable, the nasopalatine nerve block was carried out to further anaesthetise the anterior palate. Accordingly, 4 patients requiring central incisor extraction, 2 patients requiring lateral incisor extraction and one patient requiring canine extraction had to be supplemented with nasopalatine nerve block.

Once palatal anaesthesia was evaluated and recorded, infraorbital & posterior superior nerve block were then administered to block buccal tissues depending on the teeth indicated for removal. There were no additional blocks administered in the palatal region.

The study population consisted of 100 patients (45 males and 55 females) with mean age of 52 years, underwent extraction of anterior and posterior maxillary teeth of the same quadrant.

For the palatal anaesthesia only greater palatine nerve block was administered without blocking the nasopalatine nerve. Posterior superior nerve block, infraorbital or buccal field block was administered to anaesthetise the buccal tissues for posterior and anterior teeth respectively. A total of 119 anterior teeth and 143 posterior teeth were extracted.

Out of the 100 patients administered with greater palatine nerve block, it was observed that in 36 patients, the anaesthetic effect of the greater palatine nerve block extended up to the distal papilla of central incisors thereby anaesthetising the central incisors, lateral incisors, canines, premolars and molars of that side. The anaesthetic effect extended till lateral incisors in 28 patients and till canines in 20 patients. Anaesthetic effect was limited up to premolars and molars in 16 patients [Table/Fig-1].

[Table/Fig-1]:

Pictorial representation of extent of the anaesthetic effect of greater palatine nerve block.

All the 100 patients (100%) had effective posterior palatal anaesthesia after administration of the greater palatine nerve block. In only 16% of the cases the greater palatine block couldn’t supply the anterior palate required for anterior tooth removal. The remaining 84 patients (84%) had effective anterior anaesthesia.

Safe and effective pain control is essential for today’s dental practice. Our current techniques for delivery of LA to the maxilla and mandible are usually adequate for most clinical situations [9]. The maxilla is considered to be porous when compared to the more cancellous and denser mandible. Hence, maxillary nerve blocks have been very effective in providing complete anaesthesia when compared to the mandibular nerve blocks. The operator can manipulate the techniques by administering infiltrations or field blocks in the maxillary arch due to high absorption rate that adds to the painless extraction of the teeth [10].

Nerve block or infiltration in the palatal region is proven to be painful due to the close proximity of the mucosa to the bone. As per literature [11], the greater palatine and nasopalatine nerve blocks are considered to be effective for the complete anaesthesia of the palate. The patient’s perception to pain is twice in nasopalatine nerve block when compared to the greater palatine nerve block. The nasopalatine nerve block is considered to be more technique sensitive compared to the greater palatine nerve block. The relationship of the incisive papilla with respect to the central incisors and the angulation of the canal make this block more difficult. This has led to the improper usage of the technique in the form infiltrations or painful removal [10].

The results of the present study showed that, in 64 out of 100 patients considered for the study, the greater palatine nerve block successfully anaesthetised the anterior and posterior teeth including the lateral incisors, canines, premolars and molars. In 36 patients, it was observed that the anaesthetic effect of the block had extended even more anteriorly till the distal papilla of central incisors.

It was also observed that the anaesthetic effect did not reach till the interdental papilla between the two central incisors in any of the patients which may be because of the contralateral nerve supply from the opposite side. This is later confirmed in one patient, in whom bilateral greater palatine nerve blocks were administered as the patient needed bilateral teeth removal. The papilla between the central incisors was successfully anaesthetised when the block was administered bilaterally.

This study has confirmed the extended action of greater palatine nerve block in providing anterior palatal anaesthesia by anaesthetising till the anterior most area of the palate that is the central incisor.

The sample size was small and renders potential for further studies with bigger sample size.

The outcome of this study is to update and revise the techniques in exodontia for the benefit of the clinicians who have to administer multiple injections. It could also decrease the need for painful nasopalatine blocks by substituting it with a more comfortable greater palatine nerve block. This study highlights that greater palatine nerve block is similar to nasopalatine nerve block in anaesthetising the anterior palate and provides the desirable anterior palatal anaesthesia.

Adopting this practice can benefit patient compliance as well operative ease for the clinician. The trend towards evidence-based dentistry dictates that our techniques and therapies are grounded on sound clinical experiences whenever possible. However, when electing to improve his or her local anaesthetic arsenal, the clinician must be knowledgeable and clinically accurate to obtain the desired results.