بررسی ارتباط موقعیت مولر سوم مندیبل با ابعاد عمودی مختلف اسکلت صورت بر روی تصاویر پانورامیک در مراجعه‌کنندگان به دانشکده‌ی دندان‌پزشکی دانشگاه آزاد اسلامی واحد اصفهان (خوراسگان)

نوع مقاله : مقاله‌های پژوهشی

چکیده

مقدمه: با توجه به افزایش شیوع نهفتگی مولر سوم و عوارض آن و وجود اختلاف نظر در رابطه با عوامل پیش‌بینی‌کننده‌ی نهفتگی این دندان، هدف از این مطالعه، تعیین ارتباط موقعیت مولر سوم مندیبل با ابعاد عمودی مختلف اسکلت صورت بر روی تصاویر پانورامیک بود.
مواد و روش‌ها: در این مطالعه‌ی توصیفی- تحلیلی، تصاویر پانورامیک و لترال سفالومتریک 130 بیمار مراجعه‌کننده به کلینیک دندان‌پزشکی دانشگاه آزاد اسلامی واحد اصفهان (خوراسگان) در سال 1398 بررسی شدند. برای تعیین انواع اسکلت صورت از زاویه‌ی پلن مندیبولار، ایندکس جارابک و زاویه‌ی وای اکسس استفاده شد. در این پژوهش 26 نفر با فرم short face، 40 نفر با فرم normal face و 44 نفر با فرم long face بررسی شدند. زاویه‌ی β برای تعیین زاویه‌ی رویش مولر سوم مندیبل اندازه‌گیری شد. الگو و سطح رویش مولر بر اساس سیستم Per pell و Gregory و Winter طبقه‌بندی شد. داده‌ها توسط آزمون Chi- square تجزیه و تحلیل شدند (0/05 > p value).
یافته‌ها: در توزیع فراوانی الگوی رویش بین سه فرم صورت در سمت چپ فک، تفاوت معنی‌داری وجود داشت (0/048 = p value) ولی در سمت راست فک، تفاوت معنی‌دار نبود (0/11 = p value). توزیع فراوانی سطح رویش در سمت راست فک بین فرم‌های مختلف صورت تفاوت معنی‌داری نداشت (0/49 = p value)، اما در سمت چپ فک اختلاف معنی‌دار بین سه فرم صورت وجود داشت (0/049 = p value). توزیع فراوانی وضعیت نهفتگی مولر سوم مندیبل بین سه فرم صورت اختلاف معنی‌داری داشت (0/03 = p value). توزیع فراوانی زاویه‌ی رویش در سمت راست فک (0/25 = p value) و در سمت چپ فک (0/15 = p value) بین سه فرم صورت اختلاف معنی‌داری نداشت.
نتیجه‌گیری: شیوع نهفتگی در افراد Long face بیشتر از دو گروه دیگر بود. شیوع سطح و الگوی رویش مولر سوم تنها در یک سمت فک (سمت چپ) بین سه فرم صورت اختلاف معنی‌داری داشت. بین فراوانی زاویه‌ی رویش و انواع فرم اسکلت صورت در هر دو سمت فک تفاوت معنی‌داری وجود نداشت.
کلیدواژه ها: اسکلت؛ بعد عمودی؛ مندیبل؛ مولر سوم؛ نهفتگی.

عنوان مقاله [English]

Relationship between the Position of the Mandibular Third Molar with Different Vertical Skeletal Dimensions on the Panoramic Images in Patients Referred to Isfahan (Khorasgan) University Dental School

چکیده [English]

Introduction: Due to the increased prevalence of third molar impaction and the complications and existence of disagreements regarding the predicting factors for the impaction of this tooth, the aim of this study was to evaluate the relationship between the position of the mandibular third molar with different vertical skeletal dimensions on the panoramic images.
Materials and Methods: This cross sectional study was carried out on lateral cephalogram and orthopantomogram records of 130 orthodontic patients visiting to Isfahan (Khorasgan) University Dental School. Age range of the sample was 20-35 years. Various facial forms were determined with mandibular plane angle (SN-GoGn), jarabak index and Y-axis; S-GN– Frankfort plane. Beta angle; which is the angle between intersecting long axis of mandibular second molar and mandibular third molar was measured to determine the angle of eruption of mandibular third molar. Eruption pattern was classified as per Pell & Gregory and winter’s system. The data were analyzed by Chi-square test (p value < 0.05).
Results: There was a significant difference in the frequency distribution of growth pattern on the left side of the jaw (p value = 0.048). There was no significant difference in the frequency distribution of the eruption pattern in the right side of the jaw (p value = 0.11). There was no significant difference in the frequency distribution of eruption surface in the right face between different facial forms (p value = 0.49) But on the left side of the jaw there was a significant difference between the three facial forms (p value = 0.049). Frequency distribution of mandibular third molar impaction was significantly different between the three facial forms (p value = 0.03). There was no significant difference between the three facial forms in terms of frequency of eruption angle in the right side of the jaw (p value = 0.25) and also in the left side of the jaw (p value = 0.15).
Conclusion: The incidence of impaction was significantly more in patients with long face than in other two groups. The prevalence of surface and pattern of third molar eruption in only one side of jaw was significantly different between the three facial forms. There was no significant difference between the frequency of angle of eruption and facial skeletal types in both jaws.
Key word: Skeletal; Third molar; Mandible; Impaction; Vertical dimension

1. Becker A. Orthodontic treatment of impacted teeth. 4th ed. Hoboken, NJ: John Wiley & Sons; 2022.
2. Raghoebar GM, Boering G, Vissink A, Stegenga B. Eruption disturbances of permanent molars: A review. J Oral Pathol Med 1991; 20(4): 159-66.
3. Peterson LJ. Rationale for removing impacted teeth: when to extract or not to extract. J Am Dent Assoc 1992; 123(7): 198-204.
4. Hattab FN, Alhaija ES. Radiographic evaluation of mandibular third molar eruption space. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999; 88(3): 285-91.
5. Hupp JR, Tucker MR, Ellis E. Contemporary oral and maxillofacial surgery. 7th ed. St. Louis, MO: Elsevier; 2018. p. 215-48.
6. Shehanaz A. The incidence of types of mandibular third molar impactions in different skeletal face types: a clinical study. Int J Orofac Res 2017; 2(1): 24-7.
7. Hassan AH. Mandibular cephalometric characteristics of a Saudi sample of patients having impacted third molars. Saudi Dent J 2011; 23(2): 73-80.
8. Basik O, Grubor D. The incidence of mandibular third molar impactions in different skeletal face types. Aust Dent J 2008; 53(4): 320-4.
9. Bashir S, Rasool G, Afzal F, Hassan N. Incidence of mandibular 3rd molar impactions in different facial types of orthodontic patients seen at Khyber College of Dentistry. Pak Oral Dent J 2016; 36(2): 232-4.
10. Legović M, Legović I, Brumini G, Vandura I, Cabov T, Ovesnik M, et al. Correlation between the pattern of facial growth and the position of the mandibular third molar. J Oral Maxillofac Surg 2008; 66: 1218-24.
11. Melek T, Hatice K, Sevgi S. Is there a possible association between skeletal face types and third molar impaction? A retrospective radiographic study. Med Princ Pract 2019; 28(1): 70-4.
12. Upadhyaya C, Chaurasia NK, Neupane I, Srivastava S. Incidence and pattern of impaction of mandibular third molars: A single institutional experience in Nepal. Kathmandu Univ Med J (KUMJ) 2017; 15(57): 67-70.
13. Hesam Arefi A, Samimi SM, Ghorbani R. Molar impaction patterns and skeletal malocclusions. J Craniomaxillofac Res 2022; 8(4): 178-86.
14. Diniz-Freitas M, Lago-Mendez L, Gude-Sampedro F, Somoza-Martin JM, Gandara-Rey JM, Garcia-Garcia A. Pederson scale fails to predict how difficult it will be to extract lower third molars. Br J Oral Maxillofac Surg 2007; 45(1): 23-6.
15. Susarla SM, Dodson TB. Risk factors for third molar extraction difficulty. J Oral Maxillofac Surg 2004; 62(11): 1363-71.
16. Garcı́a AG, Sampedro FG, Rey JG, Vila PG, Martin MS. Pell-Gregory classification is unreliable as a predictor of difficulty in extracting impacted lower third molars. Br J Oral Maxillofac Surg 2000; 38(6): 585-7.
17. Abu Alhaija ESJ, Albhairan HM, Alkhateeb SN. Mandibular third molar space in different antero-posterior skeletal patterns. Eur J Orthod 2011; 33(5): 570-6.
18. Hattab FN, Rawashdeh MA, Fahmy MS. Impaction status of third molars in Jordanian students. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1995; 79(1): 24-9.
19. Sigaroudi A, Dalili Z, Soghrati F. Evaluation of the impaction pattern of the third molar teeth in an Iranian population [in Persian]. J Dent (Shiraz) 2010; 11(3): 247-52.
20. Ganss C, Hochban W, Kielbassa AM, Umstadt HE. Prognosis of third molar eruption. Oral Surg Oral Med Oral Pathol 1993; 76(6): 688-93.
21. Jakovljevic A, Lazic E, Soldatovic I, Nedeljkovic N, Andric M. Radiographic assessment of lower third molar eruption in different anteroposterior skeletal patterns and age-related groups. Angle Orthod 2015; 85: 577-84.
22. Manish R, Shishir B, Sujita S, Rabindra M. Position of impacted mandibular third molar in different skeletal facial types. Orthod J Nepal 2017; 7(2): 14-9.
23. Jacobson A, Jacobson RL. Radiographic cephalometry: From basics to 3-D imaging. 2nd ed. London, UK: Quintessence Pub Co; 2006. p. 110-21.
24. Shokri A, Mahmoudzadeh M, Baharvand M, Mortazavi H, Faradmal J, Khajeh S, et al. Position of impacted mandibular third molar in different skeletal facial types: First radiographic evaluation in a group of Iranian patients. Imaging Sci Dent 2014; 44(1): 61-5.