This makes it prone to anaesthesia when blocking the greater palatine nerve. Such an anatomical variation may lead to mistaking the LPF for the GPF, and thus anaesthetising the lesser palatine nerve, leading to a gagging sensation in the soft palate [9].
The nerve supply of the greater palatine nerve can also vary, as it sometime gives off branches to innervate the molar and premolar teeth [27]. The nasopalatine nerve is the largest of the nasal branches originating from the sphenopalatine ganglion.
It enters the nasal cavity through the sphenopalatine foramen, and reaches the nasal septum. Running anteriorly and inferiorly between the periosteum and the mucous membrane of the nasal septum it innervates the nasal septum filaments. Further on its course it exits the nasal cavity through the incisive foramen. Its terminal branches innervate the mucosa of the anterior part of the hard palate, and the palatal gingiva near the canine teeth.
These branches may communicate with the branches of the greater palatine nerve [14, 30]. In some cases the nasopalatine nerve can innervate the incisor teeth [22] , thus making the nasopalatine nerve block necessary to complete the anaesthesia of the central incisor [27]. Hawkins and Isen [10] describe two intra-oral techniques of blocking the maxillary nerve — the high tuberosity and the greater palatine canal approach.
The latter is associated with a higher success rate and a lower incidence of complications [40]. How-ever, the major clinical difficulty of this method is to accurately locate the position of the GPF [40]. On the other hand, the high tuberosity approach is easier for dentists, as it is essentially a high buccal infiltration [34].
However, complications may include a lack of profound anaesthesia, and a high risk of producing a hematoma from puncturing the pterygoid venous plexus [10, 40]. This block is produced at the site where the greater palatine nerve exists on the palate.
The GPF is most often located opposite the third maxillary molar. The nasopalatine nerve enters the palate through the incisive foramen, and can be clinically located through the position of the incisive papilla. Different areas of the palate can be anaesthetised by local infiltration into the papillae, especially if the procedure involves only one or two teeth [19].
During this procedure the clinician has to bear in mind the fact that the lesser palatine nerve exits in the vicinity of the GPF and its anaesthesia can lead to a gagging sensation in the soft palate, as mentioned earlier [9].
This block is commonly used to produce anaesthesia in the maxillary molars. Freuen et al. Another way to deal with such a case is to add to the posterior superior alveolar nerve block a greater palatine nerve block to enhance the anaesthetic effect [2]. The most common complication is a haematoma resulting from puncturing the pterygoid plexus.
The different origins of the posterior superior alveolar nerve compared with the middle and the anterior branches offers the possibility to anesthetise only the posterior branch. A middle superior alveolar nerve block injection should be administered if the infraorbital nerve block does not provide adequate anaesthesia to the teeth distal of the canine, or if the posterior superior alveolar injection does not provide anaesthesia for the mesiobuccal root of the first molar [34].
Through one injection, the clinician can anaesthetize the anterior and middle superior alveolar nerves, as well as the terminal branches of the infraorbital nerve.
McDaniel [21] states that an infraorbital or zygomatic nerve block, or both, produce anaesthesia in all maxillary teeth. The constancy of this point, independent of the presence or absence of teeth, is considered as the main advantage of this technique.
This field block allows anaesthetizing chosen terminal branches of the maxillary nerve. It is used for pulpal and soft tissue anaesthesia. Infection or increased bone density can diminish or abolish the anaesthetic effect. When writing about the maxillary nerve, it is worth to mention trigeminal neuralgia, as the maxillary and mandibular nerves are the ones that most often transmit pain in this disorder [25].
The reason behind this neuralgia is vascular compression of the nerves by vessel loops or aneurysms [5]. The higher prevalence of right-sided pain in this disorder can be explained by the fact that the rotundum and ovale foramina on the right side of the human cranium are significantly narrower than on the left side [25].
This can lead to easier compression of the exiting nerves. This review summarises the data on the anatomy and variations of the maxillary nerve and its branches. The mentioned variations are often the cause of anaesthesia failure or surgical complications. The authors of this manuscript wish to thank Ms Karolina Saganiak for her excellent illustrations. All authors have read and approved the final version of the manuscript.
All co-authors confirm the above-mentioned contributions and consent to the fact that this manuscript is a part of Iwona M. The co-authors confirm that Iwona M. Origin and course of the maxillary nerve The maxillary nerve, as well as its branches and their course can be seen in Figure 1.
Zygomatic nerve The zygomatic nerve arises from the maxillary nerve in the pterygopalatine fossa, passes anteriorly, superiorly, and laterally to enter the orbit through the inferior orbital fissure [14]. Infraorbital nerve The infraorbital nerve is a direct continuation of the maxillary nerve. Posterior superior alveolar nerve The posterior superior alveolar nerve branches off the maxillary nerve before it enters the infraorbital groove.
On reaching the molar teeth, the posterior superior alveolar nerve gives rise to four groups of terminal branches [23] : — Dental branches, to supply the molar and premolar roots; — Alveolar branches, to the alveolar periosteum and gingival mucosa; — Mucous branches, to supply the maxillary sinus mucosa; — Bone branches to supply the maxilla. Middle superior alveolar nerve If present, the middle superior alveolar nerve branches off the infraorbital nerve in the infraorbital canal.
Anterior superior alveolar nerve The anterior superior alveolar nerve leaves the infraorbital nerve in the orbital groove — the posterior part of the infraorbital canal [14, 33]. Palatine nerves Fig. Nasopalatine nerve Fig. Greater palatine nerve and nasopalatine nerve block This block is produced at the site where the greater palatine nerve exists on the palate.
Posterior superior alveolar nerve block This block is commonly used to produce anaesthesia in the maxillary molars. Middle superior alveolar nerve block A middle superior alveolar nerve block injection should be administered if the infraorbital nerve block does not provide adequate anaesthesia to the teeth distal of the canine, or if the posterior superior alveolar injection does not provide anaesthesia for the mesiobuccal root of the first molar [34].
Supraperiosteal injection This field block allows anaesthetizing chosen terminal branches of the maxillary nerve. Trigeminal neuralgia When writing about the maxillary nerve, it is worth to mention trigeminal neuralgia, as the maxillary and mandibular nerves are the ones that most often transmit pain in this disorder [25].
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Br J Oral Maxillofac Surg, — Higashiyama H, Kuratani S On the maxillary nerve. J Morphol, 17— J Basic Med Sci, 3: 24— Clin Anat, 61— Otolaryngol Head Neck Surg, — Ann Anat, 93— Anesth Prog, 44— Arch Ital Biol, — McDaniel WM Variations in nerve distributions of the maxillary teeth. J Dent Res, — Braz Dent J, 69— J Appl Oral Sci, — Okajimas Folia Anat Jpn, — Neto HS, Camilli JA, Marques MJ Trigeminal neuralgia is caused by maxillary and mandibular nerve entrapment: greater incidence of right-sided facial symptoms is due to the foramen rotundum and foramen ovale being narrower on the right side of the cranium.
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Singapore Med J, — Neurol Res, — Dent Update, —, — J Anat, — As a branch of the trigeminal nerve, the maxillary nerve is often implicated in trigeminal neuralgia , a rare condition characterized by severe pain in the face and jaw. When infected by the varicella zoster virus also known as shingles , persistent neuropathic nerve-associated pain is far more common than loss of sensation.
The maxillary nerve is the second of three branches of the trigeminal nerve. It arises between the trigeminal's ophthalmic and mandibular divisions in a region called the trigeminal ganglion , a cluster of nerves involved in relaying sensory information to the brain as well as chewing motor function. Medium-sized when compared to the other branches, this nerve runs forwards from each side of the head at the level of the brainstem around the ears through the walls of the sinus just beneath and to the side of the ophthalmic nerve.
It then accesses the upper gingiva via the pterygopalatine fossa a depression on each side of the skull. After giving off most of its branches it courses to the orbit of the eye via the inferior orbital fissure.
Significantly, this nerve gives off a number of important branches that play a role in conveying sensory information. Cranial nerves: Close to the origin of the maxillary nerve in the middle cranial fossa, its smallest branch arises—the middle meningeal nerve.
This brings sensory information to the dura mater the tough, outer membrane of the brain and spine. Pterygopalatine fossa: The middle course of the nerve, at the pterygopalatine fossa on each side of the skull, the maxillary nerve accesses the pterygopalatine ganglion and gives off a vast majority of its branches.
These are:. The orbit floor: As the maxillary nerve exits the pterygopalatine fossa via the inferior orbital fissure, it enters the orbit and becomes the infraorbital nerve. In turn, it splits into two branches:. Facial nerves: The final course of the maxillary nerve, after exiting the infraorbital foramen, sees the nerve divide into three sets of terminal branches:. As with many parts of the nervous system, there are sometimes variations seen in the structure of the maxillary nerve, and this is of particular concern for surgeons and dentists.
Furthermore, healthcare providers have observed variations in the mapping of associated nerves, such as cases where the superior alveolar nerve supplies regions usually serviced by the buccal nerve, and areas usually supplied by the zygomatic branch are enervated by the infraorbital nerve instead. In addition, the zygomatic branch may pass through the zygomatic bone before splitting up, as opposed to bifurcating prior to that.
Notably, there have also been cases where people have multiple infraorbital foramina as opposed to just one. This has implications for dentists and healthcare providers tasked with ensuring that the face or upper set of teeth are numbed prior to treatment.
Other variations include a greater palatine nerve—rather than maxillary nerve—that services the upper molar and premolar teeth. Finally, the nasopalatine nerve is sometimes observed innervating the incisor teeth. As noted above, the maxillary nerve is an afferent, meaning it serves a sensory function.
Finally, this sensory material passes through the trigeminal nucleus and thalamus before it is processed within the cerebral cortex. Due to its close associations with the trigeminal nerve, issues there will impact the maxillary nerve. Treatments for this condition include everything from pharmacological approaches to surgery. In facial or dental surgery, a maxillary nerve block may need to be applied by an anesthesiologist—numbing the nerve—and this procedure can also help with trigeminal neuralgia.
Other conditions can also impact the maxillary nerve, including lesions of the zygomatic nerve, which helps produce the liquid layer of film that goes around the eye. Disorders and conditions affecting the maxillary nerve can have a significant impact on quality of life. And while there is a degree to which nerves can heal on their own, there are limitations.
In cases of trigeminal neuralgia, if there is damage here or in the trigeminal nerve, most healthcare providers tend to wait three to six months to see if the case has resolved before considering surgical treatment. During this time, healthcare providers may prescribe anti-inflammatory or other drugs to aid with symptoms. Recovery varies based on treatment:. With careful monitoring and timely interventions, maxillary nerve issues—as well as the conditions that can lead to them—can certainly be taken on.
Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. National Institute of Neurological Disorders and Stroke. Trigeminal neuralgia fact sheet. Updated December 31, Shafique S, Das J. Anatomy, head and neck, maxillary nerve. Updated Maxillary branch of the trigeminal nerve.
Jones R. Repair of the trigeminal nerve: a review. Aust Dent J.
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