The Journal of Craniofacial Surgery
& Volume 24, Number 6, November 2013
Dentofacial Deformity Is Not an Appropriate Term To the Editor: The term dentofacial deformity is already in use in the maxillofacial surgery and orthodontics literature. However, the term maxillomandibular discrepancy seems to be a more specific and comprehensive substitute. Maxillomandibular discrepancy is defined as a skeletal discrepancy in size and the relative position between the maxilla and the mandible that affects functions and esthetics of the face. The first reason why maxillomandibular discrepancy is a more appropriate term than dentofacial deformity is that this type of dental and skeletal disorder is not a true deformity. The jaws and the teeth are not truly deformed, but they are generally discrepant in relative size and position. The surgical and orthodontic treatments of this disorder do not involve reshaping the teeth or the jaws, but rather they involve repositioning and resizing the jaws and dentition. True dental and facial deformities are commonly seen in orofacial malformations such as cleft lip and palate. These malformations are the result of localized errors in morphogenesis, whereas maxillomandibular discrepancy generally results from abnormalities in growth pattern. The second reason is that the term dentofacial refers only to the teeth and their contribution to the existing facial discrepancy. However, the term maxillomandibular is more comprehensive and refers to both the upper and lower jaws as well as dentition. In summary, I recommend the use of the term maxillomandibular discrepancy instead of dentofacial deformity because the former is a more accurate term and better reflects the essence of the abnormality under question. Majid Beshkar, DDS Department of Oral and Maxillofacial Surgery Shariati Hospital Tehran University of Medical Sciences Tehran, Iran [email protected]
The Neuronal Feedback (NF) Technique in Third Molar Surgery To the Editor: Mandibular third molars (M3M) could present themselves in close proximity to inferior alveolar nerve (IAN). Execution of tooth displacement and extraction of third molar roots may result in nerve injuries: neuronal lesions have a frequency that ranged from 0.5% to 8% during surgery of M3M in close proximity to IAN.1 Computed tomography (CT) scans are widely used to determine the spatial relation between the IAN and lower third molars.2 Recently, coronectomy has been introduced for intentional M3M partial removal, in order to avoid IAN lesion, but often a second intervention in years is required and possibility of many complications exists in the post-surgical time,3 so complete surgical extraction of M3M in close proximity to IAN and presurgical imaging study evaluation are still a matter of interest in international literature. In this sight, we performed a fine literature review considering the possibility of the use of a neuronal feedback (NF) of the patient during M3M surgery in order to completely extract M3M
Correspondence
and avoid IAN lesions, and we theorized a new surgical technique for extraction of M3M in close proximity to IAN, requiring the use of CT-scan presurgical study and a particular anesthesia technique. In this paper, the authors describe a new surgical technique and the outcome on patients requiring M3M surgery in communication with IAN. Recovery of patients has been measured with HealthRelated Quality of Life (HRQOL) parameters.4
PATIENTS AND TECHNIQUE A total of 30 consecutive patients, age (mean T SD) 30.5 T 8.89 years old (range 21Y45), with symptomatic partially exposed through mucosa impacted M3M were enrolled and treated between January 1 and June 30, 2012 at the Tuscan School of Dental Medicine, University of Siena, Oral Surgery Unit. At the presurgical visit, patients were asked consent agreement and the oral surgeon explained to them the intervention and the risk of IAN lesions, the aim of this study, and classic symptoms of IAN lesion in order to let the patient recognize them during the postsurgical recovery and report them. A presurgical setup was performed on all patients: after a preliminary radiographic study, CT-scan dental views were accurately studied, the number of roots and their relation with IAN was assessed, and a cleavage point for each root was theorized, without clinical evidence. A sequent Cleavage without Neuronal Pressure (CNP) point evidenced by NF was determined on CT scan and performed on each root during the NF technique. Local anesthesia was standardized on all surgical intervention and administered by the same surgeon. All interventions were executed on local anesthesia with articaine with 1:100,000 epinephrine. The theorized NF technique required a preliminary anesthesia by infiltration on the buccal fold and distally to M3M, followed by a buccal nerve anesthesia. Once the aforementioned injections were administered and the patient felt the anesthesia effect, an anesthesia of the periodontal ligament with a 27-gauge needle was executed. With this technique, we supposed to use the anesthesia effect on tooth, soft tissues, and bone, without involving the sensibility of nerve structure (IAN). Surgical protocol was standardized and all surgical procedures were carried out by the same oral surgeon with specific experience in order to reduce the operator-dependent bias. The surgical technique provided a triangular distal wedge incision behind the dental crown of the M3M and after a buccal release incision. The surgeon reflected a full-thickness flap for a complete exposure of the tooth. After a careful study of CT-scan dental views, a buccal osteotomy was performed with bur, then with high-speed turbine the crown of the tooth was cut off and completely removed, without performing any kind of pressure on bone and roots. Roots have been carefully divided, and for each root a CNP point was identified (Fig. 1). The identification of CNP point is based on a preoperative radiographic theory and an intraoperative radiographic theory clinically evidenced by NF study in which we assume that execution of pressure on a point does not cause a diffusion of pressure on the nerve. Therefore, in case of horizontal roots above the nerve, the determination of a common cleavage point below the roots, with a force directed upwards, would lead to a pressure of the apex of the root on the nerve itself, evoking the appearance of a feedback from the patient, the NF precisely. In this case, CNP point is identified buccal to the root and the maneuver of dislocation was executed. The confirmation will result from the nonappearance of the feedback. Once this technique was performed for each root, all roots were removed without damaging the IAN, the alveolar site was smoothed with attention to the IAN and irrigated with 0.9% saline solution,
* 2013 Mutaz B. Habal, MD
Copyright © 2013 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
2221
& Volume 24, Number 6, November 2013
Dentofacial Deformity Is Not an Appropriate Term To the Editor: The term dentofacial deformity is already in use in the maxillofacial surgery and orthodontics literature. However, the term maxillomandibular discrepancy seems to be a more specific and comprehensive substitute. Maxillomandibular discrepancy is defined as a skeletal discrepancy in size and the relative position between the maxilla and the mandible that affects functions and esthetics of the face. The first reason why maxillomandibular discrepancy is a more appropriate term than dentofacial deformity is that this type of dental and skeletal disorder is not a true deformity. The jaws and the teeth are not truly deformed, but they are generally discrepant in relative size and position. The surgical and orthodontic treatments of this disorder do not involve reshaping the teeth or the jaws, but rather they involve repositioning and resizing the jaws and dentition. True dental and facial deformities are commonly seen in orofacial malformations such as cleft lip and palate. These malformations are the result of localized errors in morphogenesis, whereas maxillomandibular discrepancy generally results from abnormalities in growth pattern. The second reason is that the term dentofacial refers only to the teeth and their contribution to the existing facial discrepancy. However, the term maxillomandibular is more comprehensive and refers to both the upper and lower jaws as well as dentition. In summary, I recommend the use of the term maxillomandibular discrepancy instead of dentofacial deformity because the former is a more accurate term and better reflects the essence of the abnormality under question. Majid Beshkar, DDS Department of Oral and Maxillofacial Surgery Shariati Hospital Tehran University of Medical Sciences Tehran, Iran [email protected]
The Neuronal Feedback (NF) Technique in Third Molar Surgery To the Editor: Mandibular third molars (M3M) could present themselves in close proximity to inferior alveolar nerve (IAN). Execution of tooth displacement and extraction of third molar roots may result in nerve injuries: neuronal lesions have a frequency that ranged from 0.5% to 8% during surgery of M3M in close proximity to IAN.1 Computed tomography (CT) scans are widely used to determine the spatial relation between the IAN and lower third molars.2 Recently, coronectomy has been introduced for intentional M3M partial removal, in order to avoid IAN lesion, but often a second intervention in years is required and possibility of many complications exists in the post-surgical time,3 so complete surgical extraction of M3M in close proximity to IAN and presurgical imaging study evaluation are still a matter of interest in international literature. In this sight, we performed a fine literature review considering the possibility of the use of a neuronal feedback (NF) of the patient during M3M surgery in order to completely extract M3M
Correspondence
and avoid IAN lesions, and we theorized a new surgical technique for extraction of M3M in close proximity to IAN, requiring the use of CT-scan presurgical study and a particular anesthesia technique. In this paper, the authors describe a new surgical technique and the outcome on patients requiring M3M surgery in communication with IAN. Recovery of patients has been measured with HealthRelated Quality of Life (HRQOL) parameters.4
PATIENTS AND TECHNIQUE A total of 30 consecutive patients, age (mean T SD) 30.5 T 8.89 years old (range 21Y45), with symptomatic partially exposed through mucosa impacted M3M were enrolled and treated between January 1 and June 30, 2012 at the Tuscan School of Dental Medicine, University of Siena, Oral Surgery Unit. At the presurgical visit, patients were asked consent agreement and the oral surgeon explained to them the intervention and the risk of IAN lesions, the aim of this study, and classic symptoms of IAN lesion in order to let the patient recognize them during the postsurgical recovery and report them. A presurgical setup was performed on all patients: after a preliminary radiographic study, CT-scan dental views were accurately studied, the number of roots and their relation with IAN was assessed, and a cleavage point for each root was theorized, without clinical evidence. A sequent Cleavage without Neuronal Pressure (CNP) point evidenced by NF was determined on CT scan and performed on each root during the NF technique. Local anesthesia was standardized on all surgical intervention and administered by the same surgeon. All interventions were executed on local anesthesia with articaine with 1:100,000 epinephrine. The theorized NF technique required a preliminary anesthesia by infiltration on the buccal fold and distally to M3M, followed by a buccal nerve anesthesia. Once the aforementioned injections were administered and the patient felt the anesthesia effect, an anesthesia of the periodontal ligament with a 27-gauge needle was executed. With this technique, we supposed to use the anesthesia effect on tooth, soft tissues, and bone, without involving the sensibility of nerve structure (IAN). Surgical protocol was standardized and all surgical procedures were carried out by the same oral surgeon with specific experience in order to reduce the operator-dependent bias. The surgical technique provided a triangular distal wedge incision behind the dental crown of the M3M and after a buccal release incision. The surgeon reflected a full-thickness flap for a complete exposure of the tooth. After a careful study of CT-scan dental views, a buccal osteotomy was performed with bur, then with high-speed turbine the crown of the tooth was cut off and completely removed, without performing any kind of pressure on bone and roots. Roots have been carefully divided, and for each root a CNP point was identified (Fig. 1). The identification of CNP point is based on a preoperative radiographic theory and an intraoperative radiographic theory clinically evidenced by NF study in which we assume that execution of pressure on a point does not cause a diffusion of pressure on the nerve. Therefore, in case of horizontal roots above the nerve, the determination of a common cleavage point below the roots, with a force directed upwards, would lead to a pressure of the apex of the root on the nerve itself, evoking the appearance of a feedback from the patient, the NF precisely. In this case, CNP point is identified buccal to the root and the maneuver of dislocation was executed. The confirmation will result from the nonappearance of the feedback. Once this technique was performed for each root, all roots were removed without damaging the IAN, the alveolar site was smoothed with attention to the IAN and irrigated with 0.9% saline solution,
* 2013 Mutaz B. Habal, MD
Copyright © 2013 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
2221
